Дисертації: "Dry scald"

1

Schroedter, Taylor L. "Conceptual Design of a Pilot-Scale Pressurized Coal-Feed System." BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7717.

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This thesis discusses the results and insights gained from developing a CFD model of a pilot-scale pressurized dry coal-feed system using the Barracuda CFD software and modeling various design concepts and operating conditions. The feed system was required to transport approximately 0.00378 kg/s (30 lb/hr) of pulverized coal from a vertical hopper to a 2.07 MPa (20.4 atm or 300 psi) reactor with a CO2-to-coal mass flow ratio of 1-2. Two feed system concepts were developed and tested for coal mass flow, CO2-to-coal mass ratio, steadiness, and uniformity. Piping system components also were evaluated for pressure drop and coal roping.With the first system concept, Barracuda software model parameters were explored to observe their effect on gas and particle flow. A mesh sensitivity study revealed there exists too fine of a mesh for dual-phase flow with Barracuda due to the particle initialization process. A relatively coarse mesh was found to be acceptable since the results did not change with increasing mesh refinement. Barracuda sub-model parameters that control particle interaction were investigated. Other than the close pack volume fraction, coal flow results were insensitive to changes in these parameters. Default Barracuda parameters were used for design simulations.The gravity-fed system (first concept) relied on gravity to transfer coal from a hopper into the CO2 carrier gas. This design was unable to deliver the required coal mass flow rate due to the cohesion and packing of the particles being greater than the gravity forces acting on the particles. The fluidized bed (second concept) relied on CO2 flow injected at the bottom of the hopper to fluidize the particles and transport them through a horizontal exit pipe. Additional CO2 was added post-hopper to dilute the flow and increase the velocity to minimize particle layout. This concept was shown to decouple the fluidized particle flow and dilution CO2 flow, providing significant design and operating flexibility. A non-uniform mesh was implemented to maintain a high mesh refinement in the 0.635-cm (¼-in) diameter transport pipe with less refinement in the hopper/bed region. The two main hopper diameters evaluated measured 5.08-cm (2-in) and 15.24-cm (6-in). Successful designs were achieved for each with appropriate coal mass flow rates and CO2-to-coal ratios. The particle flow was sufficiently steady for use with a coal burner.A piping system study was performed to test pneumatic transport and the effects of pipe length and bend radius. For a 1-to-1 gas-to-particle mass flow, particle layout occurred after 30 cm of travel. Particle roping occurred to various extents depending on the pipe bend radius. Bend radii of 0.318, 60.96, and 182.88 centimeters were simulated. Roping increased with bend radius and high pressure. Greater gas flow rates increased particle flow steadiness and uniformity. A simple methodology was identified to estimate the pressure drop for different piping system configurations based on the piping components simulated.

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2

Corona, Núñez Rogelio Omar. "Multi-analysis of potential and actual above ground biomass in a tropical deciduous forest in Mexico." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/28844.

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Natural tropical deciduous forest (TDF) is considered with a medium to small height (< 15 m). Particularly, in Mexico TDF shows a remnant of 36.2% of primary forest driving changes in the structure and species composition. This vegetation in Mexico is mainly transformed into grassland for cattle raising, and agriculture, primarily for self-consumption. More information about the ecology and the social pressures on this vegetation can be seen in Chapter I. The general methods, including sampling allocation and collection, characteristics of the study site, as well the procedure of the research proposal is presented in Chapter II. The main aim of this thesis is to improve the accuracy of predictions of net carbon emissions and the spatial distribution of AGB in the Tropical Deciduous Forest of Mexico. To address this aim, it is important to take into consideration the forest structure, spatial patterns and processes in a natural forest in a multi-scale analysis; also, it is necessary to characterize the spatial socio-economic drivers that influence current AGB losses. With the understanding of such elements, it is possible to reconstruct the potential carbon stocks and estimate the allocation of net carbon emissions due to deforestation and forest degradation. This study shows that it is possible to count net carbon emissions caused by deforestation and forest degradation at a landscape scale. To come to such estimates, it was necessary to reduce the different sources of uncertainty. Chapter III explores different elements that drive the AGB allocation in a mature forest. The AGB in the mature forest was considered as the potential AGB that the forest could get assuming that it has reached its steady state. Different field sampling strategies and allometric equations were evaluated to account for uncertainty in the AGB estimations. The results showed that small sampling design (300-400 m2) and large-sized plots (4 ha) produce the same tree distribution for trees: ≥30 cm in DBH as well as in AGB. These results contradict what has been reported for others (Chave et al., 2004 and 2005) when they refer to the general definition of tropical forest. However, those other studies referred to forests with a much higher precipitation and which can be classified as tropical rain (perennial) forest (Chave et al., 2004). In the tropical deciduous forest, the kind considered in this study, AGB tends to be allocated in small-sized trees. Diverse biophysical characteristics that may drive AGB allocation were considered over different spatial scales. Water stress was the main driver for AGB density at different spatial scales. Nutrients showed little significance to explain AGB as other studies have suggested in secondary forests and/or chronosequences. With this understanding, Chapter IV shows the use of different multi-variable models. Parsimonious models were the result of the variables selection and sensitivity test. Most of the methodologies showed a better performance to explain AGB allocation than a null-model. However, when they were contrasted with independent observations over different spatial resolutions, it was possible to conclude that only GLM was capable of reproducing the spatial patterns, and its estimations were close to observations. Nevertheless, some observations with very large AGB densities were underestimated by the model. This underestimation was related to the presence of few very large-sized trees. These two chapters depict the possibility of accounting for the potential AGB, and the uncertainty, namely whether the landscape could reach it with the absence of human disturbance. Once the potential AGB map was built and validated, it was transformed to carbon stock, using a local carbon concentration estimate. This potential carbon stock map was contrasted to the different available maps of current carbon stocks. Consequently, it was possible to estimate net carbon emissions due to deforestation and forest degradation (Chapter V), suggesting that the general models tend to agree in the total carbon loss. However, there are some spatial discrepancies in the magnitudes of change. Main differences between maps can be reduced by diverse socio-ecological constraints that dominate the landscape. This is important because it may be possible to make future adjustments that would reduce variability, enabling more accurate AGB estimations. However, to individually account for deforestation and forest degradation, more detailed sources of local information are necessary, such as socio-economic variables. Therefore models with a bottom-up perspective would lead to a better understanding and representation of the landscape. Finally, the growing rural population will have larger demands for wood and food, so while remote or protected areas may have the potential for storing high AGB, forest close to settlements and access routes are likely to continue being disturbed, unless affordable alternatives are available for the sustainable use of the forest. In conclusion, the estimation of spatial heterogeneity of AGB in the landscape is of great importance when measuring carbon stocks and ecological dynamics. Various elements influence the AGB allocation in the mature forest. Among all of them, water availability played the most decisive part of various spatial scales. My models support the hypothesis that water availability plays the major role in explaining AGB in Mexico on a local, sub-regional and landscape scale. Model selection produced contrasting AGB estimates and patterns. Moreover, the results of this study tell us that there is not a clear consensus among various current AGB maps. However, they also show that with a multi-model comparison it is possible to identify carbon emissions drivers and calculate total carbon emissions due to forest disturbances. Socio-economic variables played the major role in explaining AGB losses. Therefore, future studies should look into a bottom-up approach for a better understanding and representation of current AGB.

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3

Fouda, Yahia M. "Experimental and computational study of multiphase flow in dry powder inhalers." Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/16557.

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Dry Powder Inhalers (DPIs) have great potential in pulmonary drug delivery; the granular powder, used as active ingredient in DPIs, is ozone friendly and the operation of DPIs ensures coordination between dose release and patient inhalation. However, the powder fluidisation mechanisms are poorly understood which leads to low efficiency of DPIs with 10-35 % of the dose reaching the site of action. The main aim of this thesis is to study the hydrodynamics of powder fluidisation in DPIs, using experimental and computational approaches. An experimental test rig was developed to replicate the process of transient powder fluidisation in an impinging air jet configuration. The powder fluidisation chamber was scaled up resulting in a two dimensional particle flow prototype, which encloses 3.85 mm glass beads. Using optical image processing techniques, individual particles were detected and tracked throughout the experimental time and domain. By varying the air flow rate to the test section, two particle fluidisation regimes were studied. In the first fluidisation regime, the particle bed was fully fluidised in less than 0.25 s due to the strong air jet. Particle velocity vectors showed strong convective flow with no evidence of diffusive motion triggered by inter-particle collisions. In the second fluidisation regime, the particle flow experienced two stages. The first stage showed strong convective flow similar to the first fluidisation regime, while the second stage showed more complex particle flow with collisional and convective flow taking place on the same time and length scales. The continuum Two Fluid Model (TFM) was used to solve the governing equations of the coupled granular and gas phases for the same experimental conditions. Sub-models for particle-gas and particle-particle interactions were used to complete the model description. Inter-particle interactions were resolved using models based on the kinetic theory of granular flow for the rapid flow regime and models based on soil mechanics for the frictional regime. Numerical predictions of the first fluidisation regime showed that the model should incorporate particle-wall friction and minimise diffusion, simultaneously. Ignoring friction resulted in fluidisation timing mismatch, while increasing the diffusion resulted in homogenous particle fluidisation in contrast to the aggregative convective fluidisation noticed in the experiments. Numerical predictions of the second fluidisation regime agreed well with the experiments for the convection dominated first stage of flow up to 0.3 s. However, later stages of complex particle flow showed qualitative discrepancies between the experimental and the computational approaches suggesting that current continuum granular models need further development. The findings of the present thesis have contributed towards better understanding of the mechanics of particle fluidisation and dense multiphase flow in DPI in particular, and particle bed fluidisation using impinging air jet in general. The use of TFM for predicting high speed convective granular flows, such as those in DPIs, is promising. Further studies are needed to investigate the form of particle-particle interactions within continuum granular flow models.

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4

Collie, Christin. "Gaming Behaviors in Day-to-Day Life: Exploring a Problematic Gaming Behavior Scale." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etd/3496.

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Growing concern for the problematic use of video games has prompted new research in a now growing field of literature. Internet Gaming Disorder (IGD) is a proposed behavioral addiction in the Diagnostic and Statistical Manual of Mental Disorders, fifth edition (DSM-5). To examine the proposed criteria for IGD, a self-report problematic gaming behavior scale (PGBS) was developed for adults residing in the United States. One hundred eighty-nine participants completed an online questionnaire comprised of demographic items, general gaming information, the PGBS, and the Internet Gaming Disorder-20 Test (IGD-20 Test). Statistical analyses conducted at the conclusion of the study were consistent with previous research on the PGBS. Cronbach’s alpha was .908 for the 19-item PGBS, one item was removed to improve reliability. Exploratory factor analysis strongly indicated a 1-factor structure to the PGBS. Logistic regression models were fit to analyze the predictive value of the PGBS total score. The PBGS total score did not predict positive endorsement of any of the four outcome items.

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5

Costello, Kelly. "Full Scale Evaluation of Organic Soil Mixing." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6076.

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Soil mixing is a procedure that has proven to be effective for loose or soft compressible soils. The method stabilizes the soil in-place using specialized augers, tillers, or paddles that inject grout or dry cementitious powders as part of the mixing process. The Federal Highway Administration design manual for soil mixing helps to estimate the required amount of cementitious binder to produce a target design strength. However, it is biased towards inorganic soils and only mentions caution when confronting organic soils which usually come with a high water table, moisture content and void volume. The Swedish Deep Stabilization Research Centre cited studies with highly organic soils in regards to soil mixing and suggested that organic soils may need to reach a ‘threshold’ of cement content before strength gain can occur. The University of South Florida also conducted a study on highly organic soils and was able to confirm this concept. USF also proposed a threshold selection curve based on the organic content. This thesis extends this concept to the bench scale testing of multiple full scale field studies. This thesis will conclude with the presentation of new threshold curves based on the new data from the added field case studies. Given that there were variable binders and soil types used in the data analyzed, these threshold curves are dependent upon soil type and binder type, thus expanding upon the curve previously suggested.

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6

Ben-Said, Lotfi. "Reaction kinetics and mechanisms of low temperature SO 2removal by dry calcium-based sorbents." Ohio University / OhioLINK, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1173758214.

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7

Songer, Melissa A. "Endangered dry deciduous forests of Upper Myanmar (Burma) a multi-scale approach for research and conservation /." College Park, Md. : University of Maryland, 2006. http://hdl.handle.net/1903/4050.

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Thesis (Ph. D.) -- University of Maryland, College Park, 2006.
Thesis research directed by: Geography. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.

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8

Begum, Saleha. "A study of small-scale community tank irrigation systems in the dry zone of Sri Lanka." Thesis, University of Sussex, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362206.

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9

Abraham, Santosh. "Heat Transfer and Flow Measurements on a One-Scale Gas Turbine Can Combustor Model." Thesis, Virginia Tech, 2008. http://hdl.handle.net/10919/35177.

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Combustion designers have considered back-side impingement cooling as the solution for modern DLE combustors. The idea is to provide more cooling to the deserved local hot spots and reserve unnecessary coolant air from local cold spots. Therefore, if accurate heat load distribution on the liners can be obtained, then an intelligent cooling system can be designed to focus more on the localized hot spots. The goal of this study is to determine the heat transfer and pressure distribution inside a typical can-annular gas turbine combustor. This is one of the first efforts in the public domain to investigate the convective heat load to combustor liner due to swirling flow generated by swirler nozzles. An experimental combustor test model was designed and fitted with a swirler nozzle provided by Solar Turbines Inc. Heat transfer and pressure distribution measurements were carried out along the combustor wall to determine the thermo-fluid dynamic effects inside a combustor. The temperature and heat transfer profile along the length of the combustor liner were determined and a heat transfer peak region was established. Constant-heat-flux boundary condition was established using two identical surface heaters, and the Infrared Thermal Imaging system was used to capture the real-time steady-state temperature distribution at the combustor liner wall. Analysis on the flow characteristics was also performed to compare the pressure distributions with the heat transfer results. The experiment was conducted at two different Reynolds numbers (Re 50,000 and Re 80,000), to investigate the effect of Reynolds Number on the heat transfer peak locations and pressure distributions. The results reveal that the heat transfer peak regions at both the Reynolds numbers occur at approximately the same location. The results from this study on a broader scale will help in understanding and predicting swirling flow effects on the local convective heat load to the combustor liner, thereby enabling the combustion engineer to design more effective cooling systems to improve combustor durability and performance.
Master of Science

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10

Del, sorbo Pietro. "Modélisation multi-échelle des tissus secs : Application à l'impact." Thesis, Paris, ENSAM, 2019. http://www.theses.fr/2019ENAM0003/document.

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Ce travail de thèse est dédié au développement d’un modèle numérique prédictif du comportement de tissu sec soumis à l’impact à haute vitesse. La capacité d’un modèle numérique à prédire au plus juste des performances balistiques d’un tissu est étroitement liée à la bonne représentation des énergies en jeu et de la dynamique de rupture des plis. Parmi les différentes stratégies adoptées pour modéliser un tissu, les modèles mésoscopiques sont les plus populaires du fait de leur capacité à représenter fidèlement l’évolution de l’impact combinée à un coût de calcul raisonnable ; les torons sont alors traités comme des milieux continus.Pour représenter un ensemble de fibres disjointes comme un milieu continu, un modèle constitutif approprié est nécessaire. Celui généralement adopté est capable de bien représenter les propriétés longitudinales d’un toron mais limitatif pour représenter le comportement de sa section droite. Récemment, différents travaux ont démontré l’importance de la mécanique liée à la section droite d’un toron dans la rupture des tissus. Elle joue un rôle majeur pour aboutir à un modèle numérique prédictif. L’objet de cette thèse est de développer une nouvelle loi constitutive capable de surpasser les limites du modèle linéaire élastique classique tout en maintenant une bonne représentation des propriétés longitudinales du toron et un coût de calcul acceptable.La première étape a été de comprendre les phénomènes physiques et de quantifier en particulier les effets liés à la section droite du toron sur les propriétés balistiques d’un tissu. Pour répondre à cette question, deux modèles numériques à l’échelle microscopique d’un toron de Kevlar soumis à l’impact transverse ont été développés. Les résultats obtenus ont montré que la mécanique de la section droite a des répercussions sur l’initialisation de la rupture du fil mettant en jeu des énergies significatives pendant la première phase d’un impact. La nécessité de prendre en compte les aspects physiques liés à la section droite d’un toron a été finalement confirmée.A partir des résultats précédents, un nouveau modèle constitutif de toron adapté à des applications dynamiques a été développé. Une formulation hyperélastique, précédemment utilisée pour des analyses statiques a été étendue au cas de l’impact et une nouvelle approche multi-échelle a été proposée pour la détermination des paramètres matériaux. La validation de la nouvelle loi a été faite en comparant les résultats obtenus à l’échelle mésoscopique (toron) avec ceux obtenus par les analyses à la micro-échelle (fibre). L’approche proposée est capable de reproduire l’évolution de la section droite du fil pendant l’impact en gardant la bonne représentation de ses propriétés longitudinales.Par la suite, le modèle de toron proposé a été implémenté au niveau du tissu. Les résultats ont confirmé les observations faites à l’échelle du toron. Le modèle de tissu composé par des torons hyperélastiques est capable de représenter correctement la dynamique d’impact , l’évolution des énergies en jeu et la rupture du tissu. La stabilité numérique du modèle a également pu être appréciée.Finalement, le modèle mésoscopique de toron proposé permet une bonne représentation du comportement dynamique et appréhension de la rupture. Il devient ainsi un outil pratique et efficace pour la prédiction des performances balistiques de tissus
The current thesis work focused on the development of a predictive numerical model of dry fabrics under high velocity impact.A mature bibliography exists on the subject. The impact phenomenon can be essentially resumed as an energy transfer between the colliding object and the fabric layers. The correct prediction of the fabric ballistic performance by a numerical model is related to the correct representation of the fabric energy evolution and its failure dynamic. Different numerical strategies have been proposed to model a fabric under ballistic impact. Mesoscopic numerical models resulted to be the most popular since they provide a realistic representation of the phenomenon for a reasonable computational cost. This is possible thanks to the main assumption of treating yarns as continuous media.In order to represent a discrete fiber bundle as a continuum an appropriate constitutive behavior have to be formulated. The universally adopted constitutive law accurately describes yarns longitudinal properties but it is limited in the representation of their transverse mechanical behavior. Recent studies have demonstrated how this last point is intrinsically related to fabrics failure and multilayer textiles response, then its correct representation becomes a critical point for an accurate model. The goal of the current work has been to provide a new constitutive model which overcome the limitation of the classic linear elastic approach while keeping unaltered its advantages, i.e. low computational costs and accurate description of yarn longitudinal behavior.The first step of this dissertation was to quantify the yarn cross section effects over textile ballistic properties and the phenomena related to this aspect. In order to provide an answer, two microscopic numerical studies of a single Kevlar yarn transversely impacted have been presented. Results showed how yarn transverse mechanical behavior has a role in failure initialization, while its energetic contribution to the global energy balance is not negligible during the first phases of an impact. The importance of a correct representation of the yarn transverse behavior for a predictive fabric numerical model was then confirmed.Starting from the previous microscopic observations, a consistent yarn continuum model for impact applications has been proposed. An hyperelastic formulation previously developed for static applications has been extended to impact analyses and a novel multiscale approach for the determination of all the material parameters has been introduced. The validation of the hyperelastic approach has been performed comparing the results with those obtained at the microscale. Compared to the classical approach, the introduced constitutive law is actually able to reproduce the evolution of the yarn cross section during the impact while keeping a correct representation of the yarn longitudinal properties. Moreover, the proposed formulation provides new physical measurement to exploit the physic behind the impact and new possibilities in terms of failure modelisation.In the final part of the dissertation, the proposed yarn continuum model is introduced at the fabric level. Results confirmed the observation performed at the yarn level. The proposed hyperelastic approach is able to correctly represent the impact dynamic and fabric energies trends. Moreover, it provides more stability and a better representation of the fabric failure compared to linear elastic approach. The proposed hyperelastic constitutive law and the linear elastic one can be adopted for different portion of the same yarn without occurring into model instabilities and providing accurate results.The yarn mesoscopic model developed in the current work offers new possibilities in terms of failure modelisation and post processing tools. These could be used to develop more accurate fabric model and exploit the phenomena behind fabrics and yarns failure mechanic

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11

Meadows, Jillian Faith. "Development of the 4-3-2-1 Meibum Expressibility Scale and Omega-3 Fatty Acid Supplementation and Dry Eye." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1312343001.

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12

Syerko, Oléna. "Tensile and bending behavior of dry fibrous materials : experimental study and modeling by multi-scale asymptotic homogenization approach." Thesis, Lille 1, 2012. http://www.theses.fr/2012LIL10154.

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Les renforts fibreux secs utilisés dans les composites structuraux sont composés d'un arrangement de fils eux-même constitués de milliers de fibres. Etant données la complexe architecture multi-échelle et la faible cohésion entre leurs constituants, ils montrent des propriétés en traction de plusieurs ordres de grandeurs supérieurs à ceux en flexion. Dans ce contexte, ce travail porte sur l'étude de la traction et de la flexion de matériaux fibreux en tenant compte de leur réalité géométrique à l'échelle mésoscopique, à la fois expérimentalement et analytiquement. Les matériaux tissés, ayant une ondulation périodique, sont considérés. Une nouvelle méthodologie a été développée pour la modélisation du comportement de structures ondulées (avec une variable rapide) en re-projetant des forces, moments et déplacements sur l'axe neutre de la structure. Les solutions exactes des problèmes sur la traction et flexion d'une poutre sont obtenues. En parallèle, les tissus et fils extraits ont été testés en flexion et traction. Les rigidités des fils ont été extraites en couplant l'analyse d'image et une méthode inverse. En général les résultats expérimentaux ont démontré un lien entre l'ondulation de la structure et les propriétés résultantes. De plus, ils ont montré l'applicabilité de la méthode d'homogénéisation réalisée. Enfin, l'approche permet de poser et résoudre le problème d'optimisation de l'architecture fibreuse au travers de la géométrie des fils constitutifs
Dry fiber reinforcements used in structural composites consist of arrangements of yarns themselves consisting of alignments of thousands of fibers. Due to the complex multi-scale architecture and low cohesion between their constituents, they exhibit tensile properties several orders of magnitude higher than the bending ones. This work aims at studying the tensile and bending behaviors of fibrous materials, taking into account their meso-scale architecture, both experimentally and analytically. Woven fabrics, owing a periodic and corrugated geometry of their inter-weaved yarns, are under consideration. A new methodology has been developed for the modeling of the stress-strain state of corrugated structures (with fastly variable parameters) re-projecting applied forces, moments, and displacements on the neutral axis of the structure. The exact solutions for the problems about tension and bending of a beam have been obtained. In parallel, fabrics and constituting yarns have been tested on a bending set-up based on the cantilever principle. Tensile tests have also been performed on yarns extracted from the considered fabrics. Tensile and bending properties of yarns have been identified from tests coupling image analysis and inverse method. In general, the experimental results have demonstrated the link between the structure with corrugated constituents and its mechanical response to loadings. Also, they have justified the applicability of the multi-scale homogenization method for the prediction of effective properties. Finally, the approach permits to set and to efficiently solve the problem of the optimal design of fibrous materials from the crimped constituents geometry

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Schmidtke, Robert [Verfasser]. "Dry granulation via roller compaction : investigation on scale up strategies integrating process parameters and critical material attributes / Robert Schmidtke." Bonn : Universitäts- und Landesbibliothek Bonn, 2018. http://d-nb.info/116146221X/34.

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14

Correll, Eric Owen. "Design of a rapid, continuous, small-scale device for creating dry powders from concentrated suspensions containing active pharmaceutical ingredients." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/68832.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, June 2011.
"February 2011." Cataloged from PDF version of thesis.
Includes bibliographical references (p. 14).
Current methods of producing pharmaceutical compounds are large batch processes. The minimum time-to-patient for drug manufacturing is approximately 100 days. Using a continuous manufacturing process, the time-to-patient could be reduced to less than ten days. The scope of this paper encompasses the design of a machine for the desiccation of a mixture of solvent and pharmaceutical compound. The goal of this project was to provide a small-scale, high throughput method of continuous pharmaceutical drug drying for Novartis-MIT Center for Continuous Manufacturing. Specifications included a product flow rate of 100 grams per hour and a final product form of flowable powder. Several machines were built and tested, with the final design being comprised of a convective drum dryer and a modular continuous vacuum dryer.
by Eric Owen Correll.
S.B.

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15

Ghosh, Tathagata. "MODELING OF AN AIR-BASED DENSITY SEPARATOR." UKnowledge, 2013. http://uknowledge.uky.edu/mng_etds/7.

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There is a lack of fundamental studies by means of state of the art numerical and scale modeling techniques scrutinizing the theoretical and technical aspect of air table separators as well as means to comprehend and improve the efficiency of the process. The dissertation details the development of a workable empirical model, a numerical model and a scale model to demonstrate the use of a laboratory air table unit. The modern air-based density separator achieves effective density-based separation for particle sizes greater than 6 mm. Parametric studies with the laboratory scale unit using low rank coal have demonstrated the applicability with regards to finer size fractions of the range 6 mm to 1 mm. The statistically significant empirical models showed that all the four parameters, i.e, blower and table frequency, longitudinal and transverse angle were significant in determining the separation performance. Furthermore, the tests show that an increase in the transverse angle increased the flow rate of solids to the product end and the introduction of feed results in the dampening of airflow at the feed end. The higher table frequency and feed rate had a detrimental effect on the product yield due to low residence time of particle settlement. The research further evaluated fine particle upgrading using various modeling techniques. The numerical model was evaluated using K-Epsilon and RSM turbulence formulations and validated using experimental dataset. The results prove that the effect of fine coal vortices forming around the riffles act as a transport mechanism for higher density particle movement across the table deck resulting in 43% displacement of the midlings and 29% displacement of the heavies to the product side. The velocity and vector plots show high local variance of air speeds and pressure near the feed end and an increase in feed rate results in a drop in deshaling capability of the table. The table was further evaluated using modern scale-modeling concepts and the scaling laws indicated that the vibration velocity has an integral effect on the separation performance. The difference between the full-scale model and the scaled prototype was 3.83% thus validating the scaling laws.

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DANIELSSON, ELLEN, and CHRISTOPHER LEKSTRÖM. "Investigation and Optimization of Small-Scale Fecal Management : As a product from dry toilet solutions in off-grid Swedish holiday homes." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299334.

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In off-grid holiday homes, alternative toilet solutions are needed. There is a wide range of dry toilet systems, where urine-diverting systems and incineration toilets are common solutions. Urine-diverting dry toilets require that users need to manage generated fecal fractions. This is often done by private composting or through municipal latrine bucket pick-ups. In this project, fecal management for holiday homes in Sweden is examined from three perspectives by (1) studying the biological phenomenon with composting and how a compost should be managed to generate rich humus, whilst minimizing greenhouse gas emissions associated with the act of composting, (2) examine current user experiences associated with latrine compost management, and (3) map out current latrine management systems, including laws and regulations. The goal was to develop a user-friendly concept for fecal management for urine-diverting toilets, based on this research. The project was carried out in collaboration with Harvest Moon, a company focused on the development of innovative and refined dry toilet systems. The project was initiated with a literature review, the examination of current fecal management systems, and interviews with composting experts and researchers. The background research showed that there is no such thing as perfect compost management since it depends on what end goals the users have. Research also showed that frequently turning the pile, increases ammonia (NH3) emissions, but reduces methane (CH4) formation. Furthermore, biochar can be added as a bulking agent to aerate the compost mass, and aid the hygienization process of such a mass, since it binds e.g., hormones. Regarding composting methods, a static passively aerated compost is not the fastest process but has the least compost mass reduction, which is desired when using it as a soil enhancer. In addition, it requires the least management. This method was therefore chosen for further development. Furthermore, since temperature and moisture are easily measured with sensors, it was deemed interesting to implement such sensors in a final concept, to alleviate management for the user. To assure that the final concept would reflect user needs and wishes, a phase of user studies was then initiated. The studies showed that users generally see latrine compost more as something to take care of, rather than as a resource, and therefore have no interest in using composted humus. The research also showed that because many municipalities require 2-year storage of the material in the composter, users experienced scheduling issues, which ultimately led to an inefficien composting system. The third perspective that was investigated, was the management systems of today and how they are regulated by laws. Each municipality has its own requirements on how latrine composts should be managed. These requirements are based on the Environmental Code, as well as Naturvårdsverket’s recommendation for the implementation of the law. Apart from the compilation of these regulations, this investigation showed that pyrolysis, as well as the centralization of hygienized feces, could be future alternatives to latrine composting and latrine pickup. But due to the short Time-to-Market, and the project's limited time scope, product development towards system innovation was deemed unrealistic within this project. Insights from these three perspectives created a framework for the concept development phase, which was finalized with building a full-scale functional prototype. During detailed design, the concept was further developed in CAD. The final concept presented in this project is a modular, user-friendly latrine compost that can be adapted to follow different municipal regulations. It has an inner mesh that aerates the compost mass to reduce methane gas formation. The mesh is constructed with hexagonal perforated acid-proof steel. The composter has a push latch mechanism on the lid together with two gas struts, which makes it easy to open since the user only needs to push the lid once, for it to open. Temperature and moisture sensors make it easier for the user to manage their compost correctly, and a front door allows for ergonomic emptying of the finished compost humus. Future development to reduce production costs, simplify the construction, continue the CAD model development, find suitable sensors, develop product instructions as well as perform user tests with the physical prototype should be further investigated.
I fritidshus som saknar kommunalt avlopp behövs alternativa toalettlösningar. Det finns en rad olika torra toalettsystem, där urinsorterande och förbränningstoaletter är vanliga lösningar. Urinsorterande torrtoaletter kräver att användaren själv tar hand om genererade fekalier. Detta görs genom antingen privat latrinkompostering eller kommunal hämtning av latrin. I detta projekt undersöks fekaliehantering för fritidshus i Sverige från tre perspektiv genom att (1) studera biologiska fenomen i en kompost och hur en kompost ska hanteras för att få en rik humus, samt minimera växthusgasutsläpp som bildas vid just kompostering, (2) undersöka användarupplevelsen vid hantering av latrinkomposter idag, samt (3) kartlägga nuvarande system för latrinhantering, inklusive rådande lagar och förordningar. Målet med projektet var att utveckla ett användarvänligt koncept för fekaliehantering från urinsorterande toaletter, baserat på denna forskning. Projektet genomfördes i samarbete med Harvest Moon, ett företag som arbetar med att utveckla innovativa och estetiskt tilltalande torrtoalettsystem. Projektet inleddes med att studera litteratur, undersöka befintliga fekaliehanteringssystem, samt att intervjua komposteringsexperter och forskare inom området. Efter denna bakgrundsforskning kunde slutsatsen dras att det inte finns en perfekt komposthantering, då det beror på de mål som användaren har. Forskningen visade också att ju mer man vände kompostmassan, desto mer ökade utsläppen av ammoniak (NH3), dock minskade bildningen av metan (CH4). En annan insikt var att biokol kan tillsättas för att lufta, samt hjälpa till att hygienisera kompostmassan, då det binder till sig till exempel hormonrester. Gällande komposteringsmetoder så är en statisk passivt luftad kompost inte den snabbaste processen, men den leder till minst kompostreduktionen, vilket är bra om målet är att använda det komposterade materialet som jordförbättrare. Dessutom kräver det den minsta hanteringen av användaren. Denna metod valdes därför för vidareutveckling av slutkoncept. Slutligen, eftersom både temperatur och fukt lätt går att mäta med sensorer, så ansågs det intressant att implementera dessa typer av sensorer i ett slutkoncept i och med att det skulle kunna underlätta hanteringsprocessen för användaren. För att säkerställa att det slutliga konceptet skulle återspegla vad användarna behöver och önskar, inleddes sedan en fas av användarstudier. Användarstudierna visade att användare i allmänhet ser latrinkompost mer som något de måste ta hand om, än som en resurs, och har därmed inget intresse av att ta vara på det materialet som har komposterats. Studierna visade också att på grund av att många kommuner kräver två års lagring av materialet i fekaliekomposten, upplevde användare svårigheter med att få till en bra rutin kring hanteringen, vilket bidrog till att hela latrinhanteringssystemet fungerade sämre. Det tredje perspektivet som undersöktes inom projektet var hur systemen för latrinhantering ser ut idag, samt hur och av vilka lagar de regleras. Varje kommun har egna krav på hur en latrinkompost ska hanteras. Dessa krav är baserade på Miljöbalken, liksom Naturvårdsverkets rekommendationer gällande den praktiska implementeringen av Miljöbalken. Utöver sammanställningen av dessa regelverk visade studien att pyrolys, alternativt centralisering av hygieniserade fekalier, skulle kunna vara framtida alternativ till kompostering eller kommunal hämtning av latrin. Men på grund av den korta Time-to-Market för denna produkt, samt projektets begränsade tidsram ansågs produktutveckling mot systeminnovation vara orealistisk inom detta projekt. Insikter från dessa tre perspektiv bildade ett ramverk för konceptutvecklingsfasen, som avslutades med byggandet av en fullskalig funktionsprototyp. Under detaljutvecklingen fortsattes utvecklingen av konceptet i CAD. Det slutgiltiga konceptet som presenteras i projektet är en modulär, användarvänlig latrinkompost som går att anpassa till att följa olika kommunala regler. Den har en inre struktur som luftar kompostmaterialet för att minska bildandet av metangas. Strukturen består av hexagonalt perforerat syrafast stål. Komposten har en push latch mekanism på locket tillsammans med två gasfjädrar, vilket gör det enkelt att öppna eftersom användaren endast behöver trycka locket för att det ska öppnas. Temperatur- och fuktsensorer gör det lättare för användaren att hantera sin kompost korrekt, och en främre dörr möjliggör ergonomisk tömning av färdigt kompostmaterial. Framtida utveckling för att minska produktionskostnaderna, förenkla konstruktionen, vidareutveckla CAD-modellen, hitta lämpliga sensorer, utveckla användarinstruktioner, samt genomförandet av användartester med funktionsprototypen bör vidare undersökas.

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17

Delport, Hendrikus Mattheus Wessels. "The development of a DRI process for small scale EAF-based steel mills." Thesis, Stellenbosch : Stellenbosch University, 2010. http://hdl.handle.net/10019.1/17442.

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Thesis (MScEng) --University of Stellenbosch, 2010.
ENGLISH ABSTRACT: This thesis deals with the development of a new process for the production of Direct Reduced Iron (DRI), intended for use specifically by small scale Electric Arc Furnace (EAF) based steel mills, who require small volumes of DRI. The term development as used here is taken to include such aspects as conceptual design, theoretical verification and initial practical testing. The rise of EAF steelmaking brought about the metamorphosis of steel scrap from a waste product into a valuable raw material. Scrap prices rose steeply during the period 1995 to 2009 compelling EAF steelmakers, wishing to have more control over the cost of their input material, to seek for scrap supplements or alternatives. DRI has become an accepted and sought after supplement, or even complete alternative, to steel scrap. Adding DRI to an EAF charge has a range of advantages, including the dilution of tramp elements and possible cost benefits, but it does have negative effects. These include the lowering of the scrap to liquid metal yield and an increase in power consumed. The effect of charging DRI to a small EAF is quantified. The maximum DRI that may be added to the burden whilst still maintaining the present steelmaking volume, is shown to be as high as 50% if charged continuously, and the maximum price payable for DRI, is shown to be approximately 80% of base grade scrap price. Finally other requirements unique to small scale EAF operators are considered in order to prepare a schedule of requirements for a DRI plant specifically for small scale EAF steel mills. A review of published information on existing DRI production technology, processes and plants is undertaken is establish the fit of existing processes to the requirements set. Initially the thermodynamics and kinetics of iron ore reduction and coal gasification, specifically downdraft gasification are reviewed. Thereafter existing processes are reviewed. Shaft based processes and rotary kiln based processes are identified as possible suitors to the requirements. Limitations of these processes, specifically heat transfer in rotary kilns and the pressure drop over a reduction shafts are investigated. Finally a typical process in each of the main process classes is adjudicated against the set requirements. None is found to match the set requirements. A new process is proposed that is claimed to better suit to small scale operation. The uniqueness of the process is embodied in the combination of existing technologies of downdraft gasification and iron ore reduction in a shaft, in a single reactor. The process consists of two shafts, one placed above the other. Iron ore is charged into the top shaft, called the pre-heat shaft, where it is pre-heated and lightly reduced to wustite with gas from the bottom shaft, called the reduction shaft. The pre-heated ore is then charged together with coal into the reduction shaft. Gasification air is drawn into the top of the reduction shaft where the coal is gasified in a downdraft gasifier, generating reduction gas which reduces the ore as the gas moves concurrently with the iron ore. The exit gas is cleaned and pumped to the pre-heat shaft where it combusted with air to pre-heat the iron ore in the pre-heat shaft. The concept is analysed thermodynamically using amongst others, FactSage, and is shown to be thermodynamically viable. To test the concept process concept practically, an extremely small pilot plant with a production rate of 2kg DRI/h, consisting of only a gasifier/reduction shaft, was designed and constructed using reduction rate data obtained from literature supplemented with data obtained from thermogravimetric analysis of CO reduction of lump Sishen hematite. Pilot Plant trials were performed using various reductant sources. The degree of metallizaion was analysed using visual inspection of cut and polished samples compared to calibrated standards. Analysis of the results indicate that coal rate and production rate influence the degree of reduction positively and negatively. The conclusions arrived at include the fact that the process is thermodynamically viable, that it was possible to reduce iron ore in a simplified pilot plant, and that the process was found to be stable and controllable. It is recommended that a larger scale pilot plant, embodying the full proposed flow sheet be erected to test the process more completely.
AFRIKAANSE OPSOMMING: Die tesis handel oor die the ontwikkeling van ‘n nuwe proses vir die vervaardiging van sponsyster. Die proses is beoog spesifiek vir gebruik deur kleinskaalse Elektriese Boogoond (EBO) gebaseerde staal aanlegte, wat kleiner hoeveelhede sponsyster benodig. Die term ontwikkeling soos hier gebruik word aanvaar om aspekte soos konseptuele ontwerp, teoretiese verifikasie en aanvanklike toetsing te behels. Die vinnige groei van EBO staalvervaardiging het skroot getransformeer van weggooiproduk tot waardevolle grondstof. Die prys van skroot het skerp gestyg gedurende die periode 1995 to 2009. EBO gebaseerde staal produsente, in ‘n poging om meer beheer te hê oor die koste van hul insetmateriaal, het hul in ‘n toenemende mate tot skrootalternatiewe gewend. Sponsyster het ‘n aanvaarde en gewaardeerde byvoeging, en selfs alternatief tot staalskroot geword. Die byvoeging van sponsyster by die lading van ‘n tipiese EBO het besliste voordele, maar het dit ook nadelige effekte. Die voordele sluit die verdunning van reselemente en moontlike kostevoordele in, terwyl van die nadele die verlaging van die skroot tot vloeistaal opbrengs, en ‘n verhoging in kragverbruik, is. Die effek van die byvoeging van sponsyster tot ‘n EBO lading word gekwantifiseer. Daar word getoon dat die maksimum hoeveelheid sponsyster wat by ‘n EBO lading gevoeg kan word terwyl die hoeveelheid staal geproduseer konstant gehou word, ongeveer 50% is indien die sponsyster kontinue gelaai word, en die maksimum prys wat vir die sponsyster betaal kan word, word bereken op ongeveer 80% van die prys van basisgraad skroot. Ander vereistes uniek aan kleinskaal EBO bedrywers word oorweeg ten einde ‘n lys van vereistes vir ‘n sponsysteraanleg, uniek aan kleinskaal EBO bedrywers, te kan bepaal. ‘n Oorsig van gepubliseerde inligting oor sponsysterproduksietegnologie word onderneem ten einde die passing van bestaande prosesse met die gestelde vereistes te kan bepaal. Nadat die termodinamika en kinetika van ysterertsreduksie en steenkoolvergassing be-oordeel is, word bestaande sponsysterprosesse beskou. Skag- en Roterende oond gebaseerde prosesse word as moontlik gepaste prosesse identifiseer. Hitte-oordrag en die drukval oor gepakte beddens, synde tipiese beperkings eie aan die twee prosesse, woord beskou. Tipiese prosesse in elk van die hoofklasse van prosesse word ten laaste be-oordeel aan die gestelde kriteria. Daar word bevind dat geeneen van die bestaande prosesse aan die vereistes voldoen nie. ‘n Nuwe proses, wat skynbaar die behoefte van kleinskaalse EBO gebaseerde staalprodusente beter bevredig, word voorgestel. Bestaande tegnolgie word in ‘n unieke opstelling geïntegreer. Reduksie word in ‘n reduksiekag gedoen as gevolg van die ooglopende massa- en hitte-oordragvoordele van ‘n skag. Reduksiegas word verkry van steenkoolvergassing in ‘n afstroomvergasser ten einde teerverwydering in ‘n naverwerkingsstap oorbodig te maak. Die uniekheid van die proses is beliggaam in die kombinasie van ‘n steenkoolvergasser en reduksieskag in ‘n enkele reaktor. Die proses bestaan uit twee skagte, een bo die ander. Ystererts word in die boonste skag, wat die voorverhitskag genoem word, gelaai. Hier word die erts voorverhit en moontlik lig gereduseer tot wustiet met gas van die onderste skag, wat die reduksieskag genoem word. Die voorverhitte erts word saam met steenkool in die reduksieskag gelaai. Vergassingslug, word in die reduksieskag gesuig waar die steenkool in ‘n afstroomvergasser vergas word. Hierdeur word reduksiegas gegenereer wat die erts verder reduseer soos dit saamstromend met die erts af beweeg. Die uitlaatgas word gesuiwer en na die voorverhitskag gepomp waar dit verbrand word om die erts te voorverhit. Die konsep is termodinamies analiseer met gebruikmaking van onder andere FactSage, en werkbaar bevind. ‘n Baie klein, vereenvoudigde proefaanleg, met ‘n produksievermoë van 2kg DRY/uur, bestaande uit slegs ‘n reduksiekag, is ontwerp en gebou met gebruikmaking van kinetika inligting uit die literatuur aangevul met inligting uit termogravimetriese analise van die CO reduksie van Sishen hematiet. Proefaanleglopies is uitgevoer met ‘n reeks reduktantbronne. Die metallisasiegraad is bepaal deur visuele inspeksie van gesnyde, gepoleerde monsters wat vergelyk is met gekalibreerde standaarde. Analise van die resultate toon dat die steenkoolkoers ‘n positiewe verband, en die produksiekoers ‘n negatiewe verband met die metallisasiegraad het. Die slotsom waartoe gekom is, is dat die proses termodinamies werkbaar is, dat reduksie van ystererts in ‘n vereenvoudigde proefaanleg bewerk kon word, en dat die prose stabiel en beheerbaar voorgekom het. Die aanbeveling word gemaak dat ‘n groter proefaanleg wat die volledige voorgestelde vloeiskema verteenwoordig, opgerig behoort te word, ten einde die proses meer volledig te kan toets.

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18

Selkirk, Henry Box. "An investigation of 40-50 day large scale divergent circulations in the tropical troposphere." Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/58331.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric and Planetary Sciences, 1986.
Microfiche copy available in Archives and Science.
Bibliography: leaves 273-281.
by Henry Box Selkirk.
Ph.D.

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19

Negreiros, Daniel Philippi de. "Validação da versão em português da Delirium Ratting Scale revised 98 (DRS-R-98)." Florianópolis, SC, 2005. http://repositorio.ufsc.br/handle/123456789/102387.

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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde. Programa de Pós-graduação em Ciências Médicas
Made available in DSpace on 2013-07-16T00:49:20Z (GMT). No. of bitstreams: 1 221069.pdf: 483462 bytes, checksum: 1de925776bacaf63b55e90367d6331c2 (MD5)
A escala compreende 16 itens pontuados pelo clínico (13 de gravidade e 3 diagnósticos). Foi realizada a tradução da escala para o Português e posterior versão para o Inglês. Após a verificação da validade de face, a escala foi aplicada em cinco grupos de pacientes (n=64) - delirium, depressão, demência, esquizofrenia e outros, por dois avaliadores independentes e cegos ao diagnóstico. O diagnóstico e a avaliação da gravidade, medidos através da escala, foram comparados ao diagnóstico clínico, Mini Exame do Estado Mental (MEEM), Confusion Assessment Method (CAM) e Impressão clínica global (CGI). Foram realizadas análises para medir validade e confiabilidade. A curva ROC (Receiver Operating Characteristic) foi utilizada para avaliar os melhores pontos de corte para o rastreamento do delirium.

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20

Guglielmino, Edward. "A qualitative study of small-scale artist run 'Indie' music business in Brisbane." Thesis, Queensland University of Technology, 2014. https://eprints.qut.edu.au/69035/1/Edward_Guglielmino_Thesis.pdf.

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This study is an examination of three small-scale artist run music businesses based in Brisbane. The researcher embedded himself within these three environments over the space of three years, using participant observation and content analysis to establish the key motivations, theories, and ideas which drove these businesses. As a researcher participant the author also drew on his own experiences to interrogate those investigated by other researchers in the field, with the underlying key theories influenced by Pierre Bourdieu's writings on Small-Scale production. This study provides a fascinating insight into Brisbane music culture, in particular the independent music scenes.

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21

Getty, Michael. "Application of conventional and multispectral based methodology in large scale ecological land classification, a case study in dry island Buffalo jump provincial park, Alberta, Canada." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq20827.pdf.

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22

Yuan, Huaiyu. "Western United States lithosphere-asthenosphere interaction Modern day small scale convection, plume and ancient lithospheric heterogeneity /." Laramie, Wyo. : University of Wyoming, 2007. http://proquest.umi.com/pqdweb?did=1400957251&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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23

Blanchard, Monica R. "Using Network Models to Predict Steelhead Abundance, Middle Fork John Day, OR." DigitalCommons@USU, 2015. https://digitalcommons.usu.edu/etd/4477.

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In the management of threatened and endangered species, informed population estimates are essential to gage whether or not recovery goals are being met. In the case of Pacific salmonids, this evaluation often involves sampling a small subset of the population and scaling up to estimate larger distinct populations segments. This is made complicated by the fact that fish populations are not evenly distributed along riverscapes but respond to physical and biological stream properties at varying spatial extents. We used rapid assessment survey methods and the River Styles classification to explore fish-habitat relationships at a continuous network scale. Semi-continuous surveys were conducted across nine streams in the upper Middle Fork John Day River watershed and increased the number of sites surveyed eight-fold over other monitoring methods within the watershed. Using this increased sample size and continuous habitat metrics we improved watershed-wide steelhead (Oncorhynchus mykiss) abundance models. We first validated the distinctions among River Styles through a classification analysis using physical metrics measured at the rapid assessment sites. Overall classification accuracy, using a combination of reach and landscape scale metrics, was 88.3% and suggested that River Style classification was identifying variations in physical morphology within the watershed that was quantifiable at the reach scale. Leveraging the continuous River Styles classification of physical habitat and a continuous model of primary production improved the prediction of steelhead abundance across the network. Using random forest regressions, a model that included only habitat metrics resulted in R2 = 0.34, while using the continuous variables improved the model accuracy greatly to R2 = 0.65. Random forest allowed for further investigation into the predictor variables through the analysis of the partial dependence plots and identified a gross primary production threshold, below which production might be limiting steelhead populations. This method also identified the rarest River Style surveyed within the watershed, Confined-Valley Step Cascade, as the morphology that had the largest marginal effect on steelhead. The inherent physical properties and boundary conditions unique to each River Style has the potential to inform fish-habitat relationships across riverscapes and improve abundance estimates on a continuous spatial scale.

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24

Hegeman, Ericka E. "Modeling freshwater mussel distribution in relation to biotic and abiotic habitat variables in the Middle Fork John Day River, Oregon." DigitalCommons@USU, 2012. https://digitalcommons.usu.edu/etd/1274.

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The habitat requirements of western freshwater mussels, Anodonta, Gonidea, and Margaritifera, remain unclear despite their imperiled status. Freshwater mussels provide a series of ecosystem services including habitat enhancement, substratum stabilization, nutrient cycling, and water clarification, which makes their loss from aquatic ecosystems particularly detrimental. To improve the efficacy of restoration actions targeting these organisms, I used random forest modeling to investigate the biotic and abiotic factors influencing mussel density and distribution throughout a 55-kilometer (km) segment of the Middle Fork John Day River (MFJDR), in northeastern Oregon. Data was collected to characterize the occurrence of mussels with respect to the hierarchical, hydrogeomorphic structure of habitat within reaches of varying valley confinement and channel units nested within these reaches. Data regarding functional habitat features were also included to ensure that models included the wide range of characteristics that mussels need from their environment. By collecting data at both the reach and channel unit scale, I was able to investigate how mussel densities and distributions vary with spatial scale and other biophysical parameters. Throughout the study area, Margaritifera density exhibited a unimodal distribution with respect to river km, while Anodonta and Gonidea density showed a negative relationship with river km and exhibited higher densities downstream. The large scale, longitudinal trends of Margaritifera were related to hydrogeomorphic characteristics at the reach scale, while less than half of the longitudinal variation in Anodonta and Gonidea were explained by hydrogeomorphic and water quality parameters. At the channel unit scale, all mussel genera responded to the patchy variation in physical habitat characteristics, particularly habitat factors that indicated more stable parts of the channel. Overall, physical habitat characteristics such as woody debris, emergent aquatic vegetation, coarse substratum, and channel morphology were more important than hydraulic, biotic, and chemical variables. These results suggest that at both the reach and channel unit scales, mussel density and distribution are influenced by high flow refugia and the hierarchical structuring of hydrogeomorphic habitat characteristics. These results will assist mussel restoration efforts by providing specific guidance about the types of physical habitat conditions that are suitable for mussels.

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25

Crimaldi, Antonio. "Nuovi processi catalitici per la produzione di syngas." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019. http://amslaurea.unibo.it/19204/.

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The study of the combined Steam/Dry Reforming (S/DR) process for the production of syngas (CO + H2) from clean biogas was carried out using Ni/Ir bimetallic catalysts on Mg and Al mixed-oxides, obtained by calcination of hydrotalcite-type precursors (Ht) prepared by co-precipitation. The presence of small amounts of Ir promoted the catalytic activity and limited the deactivation phenomena through the formation of a bimetallic alloy, which does the catalyst very active even at lowest temperature and in lack of steam. By integrating a High Temperature–WGS unit (HTS) after the S/DR reactor it was possible to increase the H2 yield of the process. The performance of the Zn/Al/Cu-based catalyst was improved using a templating agent during the synthesis of the catalyst, which increased the catalyst’s structural properties and activity especially at lowest temperatures and at highest contact times. Finally, starting from the laboratory data, it was possible to simulate the S/DR process on industrial scale, evaluating its scalability and environmental impact. The results showed that, using the S/DR technology instead of the current processes, it was possible to reduce the energy costs and the atmospheric emissions of the plant.

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26

Meehan, Jennifer L. "29-Day Analysis of Scale Heights and the Inference of the Topside Ionosphere Over Millstone Hill During the 2002 Incoherent Scatter Radar Campaign." DigitalCommons@USU, 2017. https://digitalcommons.usu.edu/etd/6528.

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Ionospheric scale height is a measure of the topside altitude dependence of electron density and is a key ionospheric parameter due to its intrinsic connection to ionospheric dynamics, plasma temperature, and composition. A longtime problem has been that information on the bottomside ionospheric profile is readily available, but the observation of the topside ionosphere is still challenging. Despite numerous data techniques to characterize the topside ionosphere, the knowledge of the behavior of the topside ionosphere and its subsequent scale heights remains insufficient. The goal of this study is to evaluate whether or not we can characterize the topside ionospheric density and temperature profiles in the event that neither temperature nor electron density are measured by using a cost-effective method. In a simple model, the electron density in the F-region topside decreases exponentially with height. This exponential decay is mainly driven by thermal diffusive equilibrium, but also dependent on the dominant ion species, as well as other drivers during nondiffusive conditions. A scale height based on observations of the temperature can generate topside electron density profiles. While a measure of the electron density profile enables a scale height to be inferred, hence yielding temperature information. We found a new way to represent how much total electron content (TEC) is allotted for the topside ionosphere. We then used this information to successfully determine TEC using ionosonde data containing only bottomside electron density information. For the first time, slab thickness, which is directly proportional to scale height, was found to be correlated to the peak density height and introduced as a new index, k. Ultimately, k relates electron density parameters and can be a very useful tool for describing the topside ionosphere shape and subsequently, scale height. The methodology of using cost-effective, readily available ionosonde bottomside electron density data combined with GPS TEC was discovered to be capable of inferring the topside ionosphere. This was verified by incoherent scatter radar (ISR) data, though major issues surrounding the availability of ionogram data during nighttime hours greatly limited our study, especially during diffusive equilibrium conditions. Also, significant differences were found between ISR and ionosonde-determined peak density parameters, NmF2 and hmF2, and raised concerns in how the instruments were calibrated.

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Leung, Pui Kin Felix. "Quantifying the impact of present-day and future tropospheric ozone on crop productivity at global and regional scale using JULES-crop." Thesis, University of Exeter, 2016. http://hdl.handle.net/10871/29801.

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Tropospheric ozone (O3) is the third most important anthropogenic greenhouse gas. It is harmful to human health and detrimental to plant productivity, causing significant crop production losses. Currently, O3 concentrations are projected to increase globally, which could have a significant impact on food security. The Joint UK Land Environment Simulator modified to include crops (JULES-crop) is used here to quantify the impacts of present-day and future tropospheric O3 on crop production at the regional scale until 2100. These regions include the main crop producing countries. We evaluate JULES-crop against the Soybean Free-Air-Concentration-Enrichment (SoyFACE) experiment in Illinois, USA. Experimental data from SoyFACE and various literature sources is used to calibrate the parameters for soybean and ozone damage parameters in soybean in JULES-crop. The calibrated model is then applied to a transient factorial set of JULES-crop simulations over 1960-2005. Modelled yield is then compared with FAO observed yield and model performance is evaluated using Pearson correlation statistics. Yield loss and economic loss of crops due to ozone damage are evaluated. Irrigation and yield gap factors (the difference between observed and potential yields at the same location) are applied to the simulations to investigate the effect of inclusion on model performance. IPCC future climate scenarios RCP 2.6 and RCP 8.5 are employed to simulate the future impact of ozone damage on crops. Simulated yields are compared with those for the year 2050 projections from FAO. Simulated yield changes are attributed to individual environmental drivers, CO2, O3 and climate change, across regions and for different crops. A mixed scenario of RCP 2.6 and RCP 8.5 ozone and climatology, respectively, are used to explore the implication of clean air policy and climate change mitigation policy. Results show that regions with high O3 concentration such as China and India suffer the most from O3 damage; soybean is more sensitive to O3 than other crops, maize is not sensitive to O3, or to CO2 because it is a C4 crop with leaf physiology that limits the benefit from the atmospheric CO2 increase. JULES-crop predicts CO2 fertilisation would increase the productivity of vegetation. This effect, however, is offset by the negative impacts of tropospheric O3. Using data from FAO and JULES-crop, it is estimated that O3 damage has cost around 55.4 Billion USD (at today’s prices) per year for soybean. The Pearson correlation of modelled yield and observation also suggest that JULES is more sensitive to precipitation than temperature. Application of yield gap factor also improves the model performance regarding inter-annual variation. Irrigation improves the simulation of rice only, and it increases the O3 damage because drought can reduce the O3 flux entering through the plant stomata. Future climate scenario simulations show that RCP 8.5 results in a high yield for all crops mainly due to the CO2 fertilisation effect. When this effect is not included O3 damage is large in Asian countries. Mixed climate scenario simulations suggest that RCP 8.5 CO2 concentration and RCP 2.6 O3 concentration result in the highest yield. JULES-crop is still in the early stage of development and subsequently, has missing processes and can be further improved. Further work to use data from more crop FACE-O3 experiments and more crop functional types in JULES are necessary. The model will thus contribute to the understanding of the impacts of climate change on food production. In future work, JULES will later be coupled with the Unified Model to quantify the impact of tropospheric O3 on crops productivity including feedbacks between the land-surface, atmospheric chemistry and climate change.

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McCullough, Devita. "Analysis and Simulation of Switchgrass Harvest Systems for Large-scale Biofuel Production." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/36444.

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In the United States, the Energy Independence and Security Act of 2007 mandates the annual production of 136 billion liters of renewable fuel in the US by 2022 (US Congress, 2007). As the nation moves towards energy independence, it is critical to address the current challenges associated with large-scale biofuel production. The biomass logistics network considered consists of three core operations: farmgate operations, highway-hauling operations, and receiving facility operations. To date, decision-making has been limited in post-production management (harvesting, in-field hauling, and storage) in farmgate operations. In this thesis, we study the impacts in the logistics network resulting from the selection of one of four harvest scenarios. A simulation model was developed, which simulated the harvest and filling of a Satellite Storage Location (SSL), using conventional hay harvest equipment, specifically, a round baler. The model evaluated the impacts of four harvest scenarios (ranging from short, October-December, to extended, July-March), on baler equipment requirements, baler utilization, and the storage capacity requirements of round bales, across a harvest production region. The production region selected for this study encompassed a 32-km radius surrounding a hypothetical bio-crude plant in Gretna, VA, and considered 141 optimally selected SSLs. The production region was divided into 6 sub-regions (i.e. tours). The total production region consisted of 15,438 ha and 682 fields. The fields ranged in size from 6 to 156 ha. Of the four scenarios examined in the analysis, each displayed similar trends across the six tours. Variations in the baler requirements that were observed among the tours resulted from variability in field size distribution, field to baler allocations, and total production area. The available work hours were found to have a significant impact on the resource requirements to fulfill harvest operations and resource requirements were greatly reduced when harvest operations were extended throughout the 9-month harvest season. Beginning harvest in July and extending harvest through March resulted in reductions in round balers ranging from 50-63%, as compared to the short harvest scenario, on a sub-regional basis. On a regional basis, beginning harvest in July and extending harvest through March resulted in baler reductions up to 58.2%, as compared to the short harvest scenario. For a 9-month harvest, harvesting approximately 50% of total switchgrass harvest in July-September, as compared to harvesting approximately 50% in October-December, resulted in reductions in round balers ranging from 33.3- 43.5%. An extended (9-month) harvest resulted in the lowest annual baler requirements, and on average lower baler utilization rates. The reduced harvest scenarios, when compared to the extended harvest scenarios, resulted in a significant increase in the number of annual balers required for harvest operations. However, among the reduced harvest scenarios (i.e. Scenario 3 and 4), the number of annual balers required for harvest operations showed significantly less variation than between the extended harvest scenarios (i.e. Scenarios 1 and 2). As a result, an increased utilization of the balers in the system, short harvest scenarios resulted in the highest average baler utilization rates. Storage capacity requirements were however found to be greater for short harvest scenarios. For the reduced harvest scenario, employing an October-December harvest window, approximately 50% of harvest was completed by the end of October, and 100% of total harvest was completed by the third month of harvest (i.e. December).
Master of Science

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Gustafson, William Ivor. "Regional scale modeling of the Madden-Julian Oscillation using MM5 : an investigation of the importance of 30-70 day boundary effects on MJO development /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2003. http://uclibs.org/PID/11984.

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Karlsson, Caroline. "Teknikutvärdering av Urintorkning i Pilotskala – ett Fältförsök i Finland : Technical Evaluation of Urine Drying in Pilot Scale - a Field Experiment in Finland." Thesis, Sveriges lantbruksuniversitet, Institutionen för energi och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-397987.

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Av samtliga globala processer som reglerar jordsystemet är de biogeokemiska flödena av kväve (N) och fosfor (P) mest påverkade av mänskliga aktiviteter. Inerta former av N och P omvandlas till reaktiva former som sprids i miljön, där de orsakar eutrofiering och påverkar marina ekosystem negativt. Majoriteten av de reaktiva N- och P-formerna används för framställningen av mineralgödsel. Ett alternativt sätt att producera gödsel är att återvinna näringsämnena i avloppet. En teknik som återvinner näringsämnen i urin är basisk urintorkning. Teknologin stabiliserar urea med ett basiskt torkningsmedium och koncentrerar näringsämnena genom att evaporera vattnet i urinen. Slutprodukten är ett torrt gödsel i pulverform. I det här projektet testades urintorkningsteknologin för första gången i ett fältförsök. Ett system för urintorkning med kapacitet att förånga 40 kg urin dygn-1 m-2 konstruerades och integrerades i ett befintligt torrt sanitetssystem för användning under en period på tre månader. I projektet utvärderades 13 dygn av de 3 månaderna. Resultaten visade att 24 kg urin tillfördes systemet och att systemet kunde upprätthålla en kontinuerlig torkning av urinen. Efter torkningen återvanns majoriteten (97 %) av N i slutprodukten. På grund av att den tillförda mängden urin var liten blev växtnäringshalterna i slutprodukten och i torrsubstansen (TS) av slutprodukten låga. Systemet hade emellertid potential att torka mycket större kvantiteter urin. Om systemets fulla potential hade använts, det vill säga att torka 40 kg urin dygn-1 m-2, så hade särskilt N- och P-halterna ökat avsevärt. N-halterna hade även ökat ytterligare om torkningen hade utförts vid en lägre temperatur. Systemets energiförbrukning var hög, eftersom systemet hade en kontinuerlig energikonsumtion och även komponenter med hög effekt. I jämförelse med den konventionella avloppsvattenreningen och produktionen av mineralgödsel har systemet en hög energikonsumtion, men i jämförelse med en förbränningstoalett är systemets energiförbrukning likvärdig. För att minska energiförbrukningen kunde reglertekniska åtgärder utföras så att systemets energitillförsel upphör när systemet inte används. Systemets energiförbrukning får även ställas i relation till de problem som dagens system för livsmedelsproduktion och sanitet medför. Till skillnad från nämnda system möjliggör urintorkningsteknologin besparing av dricksvattenresurser, ett slutet kretslopp av näringsämnen och en minskad påverkan på miljön.
Of all global processes that regulate the earth system, the biogeochemical flows ofnitrogen (N) and phosphorus (P) are the most affected by human activities. Inert forms of N and P are converted into reactive forms that are dispersed in the environment, causing eutrophication and affecting marine ecosystems. The majority of the reactive N and P are used for the production of mineral fertilizers. An alternative way of producing fertilizers is to recycle nutrients from waste water. A technology that reuses nutrients in urine is alkaline urine drying. The technology stabilizes urea with an alkaline drying medium and concentrates the nutrients by evaporating the water in urine. The end-product is a dry fertilizer in powder form. In this master project, the alkaline urine drying technology was tested for the first time in field conditions. A system for urine drying with the capacity to evaporate 40 kg of urine day-1 m-2 was constructed and integrated into an existing dry sanitation system for use over a period of three months. The master project evaluated the system for 13 days of the 3 months. The results showed that 24 kg of urine was collected in the system, significantly less than what the system had been designed to dry. Furthermore, the results showed that the system functioned smoothly recovering 97 % of the urine-N in the end-product. The nutrient content in the end-product and the dry matter of the end-product was low due to the low amount of urine that was collected. However, the system had the potential to dry much larger quantities of urine. If the system would have been operated to function at full potential (drying 40 kg of urine day-1 m-2) the N- and P-content in the end-product would be much higher than that observed during the 13 days. Furthermore, the system if operated at lower temperatures has the potential to recover more N. The system’s energy consumption was high, as the system had a continuous energy consumption. In comparison with the conventional waste water treatment and the production of mineral fertilizers, the system has a high energy consumption, but compared to an incineration toilet, the system’s energy consumption is equivalent. In order to reduce the energy consumption, automatic control could be implemented so that the energy is switched off when the system is not used. The system’s energy consumption may also be set in relation to the problems that today’s systems for food production and sanitation entail. Unlike the aforementioned systems, the urine dehydration technology does not consume drinking water, it enables recycling of nutrients as well as a reduced impact on aquatic life.

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Moisio, Mitchell D. "The Utility of the Child and Adolescent Functional Assessment Scale (CAFAS) in Identifying Outcomes of Students with Emotional Disturbance Served in a Day Treatment Program." Cleveland State University / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=csu1249063801.

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Furniss, Allison. "“Je Cherche La Vie!”: Women's Labour Politics in Masisi's Artisanal Coltan Mines." Master's thesis, Faculty of Humanities, 2021. http://hdl.handle.net/11427/33895.

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In considering how women navigate the complexity and gendered aspects of the artisanal mining industry, this study seeks to unpack women's labour at step one of the global supply chain of coltan, in the post-conflict context of eastern Democratic Republic of Congo (DRC). Female miners are largely excluded from mine work by blurry regulatory frameworks, gendered social norms and financial disparities, however they manage to remain active labourers in the artisanal mining industry. Within a broader socio-political context of poverty, political instability and rural livelihoods, women maintain access to mine work through strategies, often premised on a gendered solidarity, such as organizing into collectives, engaging in small group collaborations and employing creative ruses to maintain the secrecy of their labour. This thesis seeks to analyze women's exclusions from mine work and the subsequent strategies they employ to circumvent those exclusions and maintain work in the mines. Based on three months of ethnographic fieldwork at artisanal coltan mine sites in Masisi Territory in the province of North Kivu, this study employs ethnographic observations, focus group and interview methodologies.

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Buchmann, Thies Joachim. "3D multi-scale finite element analysis of the present-day crustal state of stress and the recent kinematic behaviour of the northern and central Upper Rhine Graben /." Berlin : Logos-Verl, 2008. http://d-nb.info/990771296/04.

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Bartoli, Florian. "Croissance de films minces piézoélectriques de ScxAl1-xN par pulvérisation cathodique pour la réalisation de dispositifs à ondes élastiques confinées, destinés à des applications haute-température." Electronic Thesis or Diss., CentraleSupélec, 2019. http://www.theses.fr/2019CSUP0015.

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Certaines industries demandent le développement d’un capteur résistant à des environnements hostiles (températures au-delà de 700°C, et atmosphères nocives), tout en permettant des mesures sans-fil. Si les dispositifs de type SAW permettent ces dernières, actuellement elle ne permet pas l’utilisation en conditions extrêmes, les matériaux les composant étant peu résistant à ces environnements. Il est possible d’encapsuler ces dispositifs dans des boîtiers pour augmenter leur viabilité, mais seulement jusqu’à 300°C. On cherche alors à réaliser un capteur auto-protégé. Il serait constitué d’une structure à trois couches, la couche centrale servant de guide à l’onde élastique. Les couches externes serviraient à confiner l’onde dans la couche guidante, et à protéger cette dernière des attaques chimiques. Cette structure est appelée WLAW (Waveguiding Layer Acoustic Wave). Dans cette thèse, on étudie l’intérêt du matériau ScAlN en tant que couche piézoélectrique, et on teste la viabilité de la structure WLAW pour notre application. Les films minces de ScAlN n’étant pas disponibles dans le commerce, nous avons développé un procédé de croissance. Des films de Sc0.09Al0.91N et Sc0.18Al0.92N ont été réalisés par pulvérisation cathodique magnétron. La microstructure des films a été déterminée par DRX, et par microscopie électronique en transmission. Des couches minces de ScAlN hétéro-épitaxiées ont été obtenues. Le comportement de dispositifs Sc0.09Al0.91N/saphir ont été testés jusqu’à 575°C. La réalisation d’un dispositif WLAW a aussi été effectuée, en utilisant des substrats de GaN/Saphir achetés dans le commerce. Des simulations ont permis de déterminer une structure AlN/GaN/Saphir pouvant confiner l’onde. Le bon confinement de l’onde dans le matériau piézoélectrique (ici le GaN), ainsi que la viabilité d’une telle structure à la température a été vérifié
Some industries require the development of a sensor that is resistant to hostile environments (temperatures above 700°C, and aggressive atmospheres), while allowing wireless measurements. While SAW-type devices allow these measurements, it currently does not allow for use in extreme conditions, as the materials are not resistant to these environments. These devices can be encapsulated in packages to increase their viability, but only up to 300°C. We then try to make a self-protected sensor. It would consist of a three-layer structure, the central layer serving as a guide to the acoustic wave. The outer layers would serve to confine the wave in the guiding layer and protect it from chemical attack. This structure is called WLAW (Waveguiding Layer Acoustic Wave). In this thesis, we study the interest of the ScAlN material as a piezoelectric layer, and we test the viability of the WLAW structure for our application. Since thin ScAlN films are not commercially available, we have developed a growth process. Films of Sc0.09Al0.91N and Sc0.18Al0.92N were made by cathodic magnetron sputtering. The microstructure of the films was determined by XRD, and by transmission electron microscopy. Thin layers of hetero-epitaxial ScAlN were obtained. The behavior of Sc0.09Al0.91N/Sapphire devices were tested up to 575°C. The realization of a WLAW device was also carried out, using commercially purchased GaN/Sapphire substrates. Simulations have determined an AlN/GaN/Sapphire structure that can confine the wave. The proper containment of the wave in the piezoelectric material (here the GaN), as well as the viability of such a structure at temperature has been verified

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He, Yanping. "Representations of boundary layer cloudiness and surface wind probability distributions in subtropical marine stratus and stratocumulus regions." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/22585.

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Thesis (Ph. D.)--Earth and Atmospheric Sciences, Georgia Institute of Technology, 2007.
Committee Chair: Dr. Robert E. Dickinson; Committee Member: Dr. Irina Sokolik; Committee Member: Dr. Judth Curry; Committee Member: Dr. Peter Webster; Committee Member: Dr. Rong Fu.

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Silveira, Scheila Machado da. "Qualidade do atendimento de creches: análise de uma escala de avaliação." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/59/59137/tde-13102009-160038/.

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No momento em que a creche integrou o sistema educativo brasileiro, o Estado depara-se com o desafio de estabelecer parâmetros de qualidade e critérios de avaliação do atendimento oferecido às crianças de 0-6 anos. Desta maneira, uma avaliação instrumentalizada da qualidade de ambientes de creches poderia auxiliar nesta tarefa. Dada a inexistência de instrumentos brasileiros, esta pesquisa objetivou verificar a adequabilidade para o nosso contexto da versão traduzida da escala norte-americana Infant/Toddler Environment Rating Scale Revised Edition, utilizada internacionalmente para avaliar a qualidade do atendimento oferecido para crianças de 0-30 meses. Essa escala é composta por 39 itens agrupados em sete subescalas, que contemplam diversas dimensões do ambiente de creches: Espaço e mobiliário (5 itens); Rotinas de cuidado pessoal (6); Falar e compreender (3); Atividades (10); Interação (4); Estrutura do programa (4); Pais e equipe (7). Tais itens servem de guia para observações feitas nas várias áreas da creche, durante atividades rotineiras de uma turma de crianças e sua(s) educadora(s); com base nas condições observadas e nas descrições dos indicadores de qualidade da escala, o avaliador atribui pontuação de 1 (inadequado) a 7 (excelente) para cada item. Esta pesquisa englobou quatro etapas: (1)análise semântica; (2)treinamento e familiarização com a escala; (3)verificação da discriminabilidade; (4)verificação da concordância entre aplicadores treinados. Na Etapa 1, seis participantes avaliaram se as sentenças escritas nos indicadores de qualidade da escala expressavam claramente o que deveria ser observado. Dos 466 indicadores, 80% foram considerados compreensíveis por todas as participantes; os 93 indicadores considerados com dificuldades de compreensão semântica passaram por revisão e 57% foram reescritos. Na Etapa 2 (treino através de vídeo e aplicação da escala em três turmas, uma de creche universitária e duas de creche filantrópica), o índice de acordo obtido entre dois aplicadores na terceira turma (82%) permitiu encerrar o treinamento. Na Etapa 3, a escala foi aplicada em quatro turmas de creches com tipos diferentes de gestão (universitária, municipal, filantrópica e particular) a escala discriminou níveis diferentes de qualidade, conforme o escore total obtido (E.T.): as turmas Universitária (E.T.=4,97) e Municipal (E.T.=3,33) apresentaram nível de qualidade suficiente e as turmas Filantrópica (E.T.=2,7) e Particular (E.T.=1,57), nível de má qualidade. Na Etapa 4, dois aplicadores treinados avaliaram, simultânea e independentemente, duas turmas, uma de creche municipal e outra universitária; o Coeficiente de Correlação Intraclasse indicou uma concordância quase perfeita (0,83) e substancial (0,66), respectivamente para cada turma; a análise de concordância sugeriu um nível satisfatório de precisão da escala. As avaliações realizadas identificaram, em cada turma, aspectos positivos da qualidade do atendimento e aspectos que necessitam de melhorias, os quais foram apresentados às coordenadoras das creches, favorecendo reflexões/discussões sobre qualidade do atendimento e oferecendo a elas subsídios para trabalhar com as educadoras; pois, para promover um ambiente institucional de qualidade é importante que a equipe discuta e reflita sobre aspectos positivos já presentes e aqueles que necessitam de planejamento para serem implantados. Desta maneira, a escala pode ser um instrumento útil na promoção de qualidade do atendimento infantil em creches brasileiras.
At the moment that day care center was incorporated to Brazilian educational system, the State come across with the challenge of establishing quality parameters and criteria for evaluation of services provided to children of 0-6 years. Thus, assessment the environmental quality of day care center by an instrument could help in this task. Because of the nonexistence of Brazilian instruments, this research aimed to verify the suitability for our context of translated version of the North American scale Infant/Toddler Environment Rating Scale - Revised Edition, used internationally to assess the quality of services offered for children of 0-30 months. This scale consists of 39 items grouped into seven subscales, which include various dimensions of day care center environment: Space and furnishings (5 items), Personal care routines (6); Speaking and understanding (3) Activities (10); Interaction (4) Program structure (4) Parents and staff (7). These items serve as a guide for observations made in various areas of day care center, during routine activities of a group of children and their teacher(s); based on observed conditions and descriptions of quality indicators of the scale, the evaluator assigns scores of 1 (inadequate) to 7 (excellent) for each item. This study included four phases: (1) semantic analysis, (2) training and familiarization with the scale, (3) verification of the scales discrimination, (4) verification of agreement between trained evaluators. In the Phase 1, six participants judged if the written phrases of quality indicators of the scale expressed clearly what should be observed. Of the 466 indicators, 80% were considered understandable by all participants, the 93 indicators considered not understandable underwent revision and 57% have been rewritten. In the Phase 2 (training through video and application of scale in three playrooms, a playroom of an university day care center and two playrooms of a philanthropic day care center), the agreement between two evaluators in the third playroom (82%) allowed finishing the training. In Phase 3, the scale was applied in four playrooms of day care centers with different types of management (university, public, private and philanthropic) - the scale discriminated different levels of quality, according to the total score obtained (T.S.): the playrooms University (T.S. = 4.97) and Public (T.S.= 3.33) had sufficient level of quality and the playrooms Philanthropic (T.S.= 2.7) and Private (T.S.= 1.57), level of poor quality. In Phase 4, two trained evaluators assessed, at the same time and independently, two playrooms, a playroom of a public day care center and another university; the intraclass correlation coefficient indicated an almost perfect correlation (0.83) and substantial agreement (0.66), respectively for each class, the analysis of agreement suggested a satisfactory level of accuracy of the scale. The evaluations identified, in each class, the positive aspects of quality of service and aspects that need improvement, which were presented to the day care centers coordinators, encouraging reflections and discussions about quality of service and offering them subsidies for working with educators; because, to promote the quality of institutional environments is important that the team discuss and reflect on positive aspects already present and those that require planning to be implemented. Thus, the scale may be a useful tool in promoting quality of service provided to children in Brazilians day care centers.

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Souza, Janaina Medeiros de. "Avaliação do desenvolvimento neuropsicomotor de crianças entre 06 e 24 meses de creches de Florianópolis - SC." Universidade do Estado de Santa Catarina, 2003. http://tede.udesc.br/handle/handle/386.

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The objective of this study was to evaluate the neuropsychomotor development and to describe biossocials aspects of the children between 06 and 24 months old on the public day care centers, analysing the differences related to the gender and the age groups. It is a descriptive diagnostic research, of 221 children enrolled on the nursery division, of 14 day care centers at Florianópolis (selected in a probabilistic way), accomplished between July and December of 2002. The children were evaluated using the Brunet and Lézine Scale of Psychomotor Development in First Infancy (1981), obtaining their development ages and their development quotients in different areas as motor, oculomotricity, language and social, besides global. Also as an instrument, it was used a questionnaire for the parents, to collect some informations about their age, occupation and scholarship, how much they earn, the conditions of their houses, disturbance before, during and after birth, height and weight on birth and the children development. It has been developed specifically for this study a software that calculates, record and create a data file with the results obtained on the tests, which is called SIMODE. To analyse the data it was used the statistical software EPINFO 6.0: it was applied descriptive statistics (average, standard deviation, median, variance, quartiles and extreme values) for the tests and questionnaire; for the comparison related to the gender and age group (06 to 12, 12 to 18 and 18 to 24 months old) it was applied inferencial statistics (Student s t test, ANOVA test, Mann-Whitney nonparametrical tests and Kruskall-Wallis test). Some parents didn t answer all the questions on the questionnaire, but it was possible to evidence that a great part of the families have a low income on economical and social areas, however the mothers are supported by acceptable community and familiar net and their children didn t have any serious health problem. The results showed that the average development of the children on the selected group was practically proper to their age on motor area (QDP=106,7), oculomotricity area (QDC=96,6), social area (QDS=94,8) and on global development (QDG=97,8), with a small deficit on the language area (QDL=90,7; however they are all inside a normal average profile. Related to the sex, it was found significant differences in favour of the girls on the global development (p=0,003), oculomotricity area (p=0,0005), language area (p=0,013) and social area (p=0,023). In the comparison related to the age group, the children between 18 and 24 months old are significantly superiors on the motor development area (p<0,005) and on the language development area (p=0,0001); the children in the age group from 06 to 12 months old and from 12 to 18 months old showed a low normality profile at the language area. Conclude that the day care center environment, offers larger spaces, more toys and materials and the possibility of being in touch with many other children when compared to the children s house. It seems that it has produced a proper development on the motor, oculomotricity and social areas. However, we believe that the reduced relation teacher per children group can limit the ideal interaction and stimulations to the language development, due to the necessary, but exhausting, routine on feeding and hygiene of the children.
O objetivo deste estudo foi avaliar o desenvolvimento neuropsicomotor e descrever aspectos biossociais de crianças entre 06 e 24 meses de creches públicas, analisando as diferenças em relação ao sexo e às faixas etárias. Trata-se de uma pesquisa descritiva diagnóstica, de 221 crianças matriculadas nas turmas de berçário, de 14 creches municipais de Florianópolis (selecionadas de forma probabilística), realizada no período de julho a dezembro de 2002. As crianças foram avaliadas através da Escala de Desenvolvimento Psicomotor da Primeira Infância de Brunet e Lézine (1981), obtendo-se suas idades (IDs) e quocientes de desenvolvimento (QDs) global e nas áreas postural, oculomotriz, da linguagem e social. Também como instrumento, foi utilizado um questionário direcionado aos pais, para coleta de informações sobre idade, profissão e escolaridade dos mesmos, renda familiar, condições de moradia, intercorrências pré, peri e pós-natais, além de peso e estatura ao nascimento e desenvolvimento evolutivo das crianças. Desenvolveu-se especialmente para o estudo um software que calcula, registra um perfil e forma um banco de dados dos resultados obtidos nos testes, intitulado SIMODE. Para a análise dos dados foi utilizado o programa estatístico EPINFO, versão 6.0: empregou-se estatística descritiva (média, desvio-padrão, mediana, variância, quartis e valores extremos) para as variáveis dos testes e do questionário e estatística inferencial (Teste t de Student, ANOVA e testes não-paramétricos de Mann- Whitney e de Kruskall-Wallis) para comparação em relação ao sexo e por faixas etárias (06 aos 12, 12 aos 18 e 18 a 24 meses de idade). As informações dos questionários não contemplaram a totalidade da amostra, mas foi possível constatar que se tratam em grande parte de famílias de baixo rendimento sócio-econômico, porém as mães possuem uma rede de apoio comunitária e familiar aceitável e cujos filhos não tiveram problemas graves de saúde. Os resultados demonstraram que o desenvolvimento médio das crianças da amostra encontra-se praticamente apropriado as suas idades nas áreas postural (QDP=106,7), oculomotriz (QDC=96,6), social (QDS=94,8) e global (QDG=97,8), com ligeiro déficit na área da linguagem (QDL=90,7); porém todos dentro do perfil de normalidade média. Em relação ao sexo, foram encontradas diferenças significativas em prol das meninas no desenvolvimento global (p=0,003), oculomotriz (p=0,0005), da linguagem (p=0,013) e social (p=0,023). Na comparação entre as faixas etárias, as crianças entre 18 e 24 meses são significativamente superiores em relação às demais no desenvolvimento postural (p<0,005) e da linguagem (p=0,0001); sendo que as crianças entre 06 e 12 e entre 12 e 18 meses apresentaram um perfil de normalidade baixa na área da linguagem. Conclui que o ambiente da creche, por oferecer maiores possibilidades de espaço, brinquedos e materiais e contato com outras crianças, em relação ao que é proporcionado na maioria dos lares, parece ter produzido um desenvolvimento adequado nas áreas postural, oculomotriz e social. Entretanto, pensamos que o número reduzido de professoras por aluno possa estar restringindo as interações e estimulação adequadas ao desenvolvimento da linguagem, devido ao necessário, porém exaustivo, trabalho nas rotinas de higiene e alimentação.

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Cewers, Ingrid, and Viveka Palmqvist. "Patientens upplevelse av smärtbehandling efter operation av distal radiusfraktur med perifer nervblockad." Thesis, Röda Korsets Högskola, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:rkh:diva-101.

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Syftet med studien var att utvärdera patientens upplevelse av den postoperativa smärtan och behandlingen av denna när den perifera nervblockadens effekt avtagit efter operation av distal radiusfraktur. Metoden som använts är en empirisk kvantitativ deskriptiv enkätstudie. Tjugo patienter deltog i denna pilotstudie. Demografin stämde väl överens med de statistiska data, som visar att distrala radiusfrakturer är vanligt förekommande hos kvinnor i åldern 55 år och äldre. Resultatet av studien har påvisat att många patienter har upplevt mer smärta än vad de själva varit beredda på. Slutsatsen utifrån visuell analog skala, VAS, visar att smärtan har varit svår för patienterna att behandla hemma trots att de haft tillgång till smärtbehandlade läkemedel. Informationen som patienten erhållit har varit otillräcklig och kan vara en källa till den svårbemästrade smärtan.
The aim of the study was to evaluate patient´s experience of the postoperative pain and its treatment after peripheral nerve blockade for operation of a distal radius fracture had ceased. The method used was an empiric, quantitative, descriptive study using enquiries. Twenty patients participated in this pilot study. Demography was according to statistical data, that distal radius fractures are common in women aged 55 or more. The results showed that many patients experienced more severe pain than expected. The conclusion from visual analogue scale, VAS, shows that the pain was difficult to treat at home in spite of prescription of pain killers. The information given to the patient was insufficient, which may have contributed to the difficulty to control pain.

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Ribas, Giovana Ghisleni. "MELHORA NA SIMULAÇÃO DA PRODUTIVIDADE DE ARROZ NO RIO GRANDE DO SUL PELA INTRODUÇÃO DE ARROZ HÍBRIDO NO MODELO SIMULARROZ." Universidade Federal de Santa Maria, 2016. http://repositorio.ufsm.br/handle/1/7623.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
The importance of hybrid rice is increasing because of its higher potential yield compared to n conventional varieties traditionally sown in southern Brazil. The SimulArroz model is a dynamic deterministic mathematical model that simulates the growth, development and grain yield in rice, but the current version of SimulArroz (version 1.0) does not contain the option for hybrid rice. The objective of this dissertation was to calibrate and evaluate the performance of SimulArroz model in simulating the number of leaves, phenology, dry matter accumulation and grain yield of three hybrid rice cultivars in Rio Grande do Sul State, Brazil. Field experiments were conducted in Santa Maria, and in research stations of the Instituto Rio Grandense do Arroz in Cachoeirinha, Uruguaiana, Santa Vitória do Palmar, Cachoeira do Sul, Bagé and Camaquã. The number of main stem leaves, based on the Haun scale, and phenology, based on the Counce scale, and also, plant samples were collected in Santa Maria and Cachoeirinha to determine the dry matter of shoots, leaves, culms, senescent leaves and grain yield. The SimulArroz model is calibrated and evaluated to simulate the number of leaves on the main stem, represented by Haun Stage, phenology, the total dry matter above ground, leaves, stems, senescent leaves and grain yield at 13 % moisture of three hybrid rice cultivars in Rio Grande do Sul.
O arroz híbrido vem ganhando importância por apresentar um potencial produtivo maior do que as cultivares convencionais tradicionalmente semeadas no Sul do Brasil. O modelo SimulArroz é um modelo matemático dinâmico determinístico que simula o crescimento, o desenvolvimento e a produtividade de grãos na cultura do arroz, no entanto a versão atual do SimulArroz (versão 1.0) não contém a opção de simulção para arroz híbrido. Assim, o objetivo nesta dissertação foi calibrar e avaliar o desempenho do modelo SimulArroz em simular o número de folhas, fenologia, o acúmulo de matéria seca e a produtividade de três cultivares de arroz híbrido no Rio Grande do Sul. Foram conduzidos experimentos de campo em Santa Maria, e nas estações regionais de pesquisa do Instituto Rio Grandense do Arroz de Cachoeirinha, Uruguaiana, Santa Vitória do Palmar, Cachoeira do Sul, Bagé e Camaquã. Foram determinados o número de folhas do colmo principal através da escala da Haun e a fenologia conforme a escala de Counce, e também, foram realizadas amostragens de plantas em Santa Maria e Cachoeirinha para determinar a matéria seca total da parte aérea, de folhas, de colmos, de folhas senescentes e produtividade de grãos. O modelo SimulArroz está calibrado e avaliado para simular o número de folhas no colmo principal, representado pelo Estádio de Haun, a fenologia, a matéria seca total da parte aérea, de folhas, de colmos, de folhas senescentes e a produtividade de grãos a 13% de umidade de três híbridos de arroz irrigado no Rio Grande do Sul.

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Souihi, Nabil. "Multivariate Synergies in Pharmaceutical Roll Compaction : The quality influence of raw materials and process parameters by design of experiments." Doctoral thesis, Umeå universitet, Kemiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-96441.

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Roll compaction is a continuous process commonly used in the pharmaceutical industry for dry granulation of moisture and heat sensitive powder blends. It is intended to increase bulk density and improve flowability. Roll compaction is a complex process that depends on many factors, such as feed powder properties, processing conditions and system layout. Some of the variability in the process remains unexplained. Accordingly, modeling tools are needed to understand the properties and the interrelations between raw materials, process parameters and the quality of the product. It is important to look at the whole manufacturing chain from raw materials to tablet properties. The main objective of this thesis was to investigate the impact of raw materials, process parameters and system design variations on the quality of intermediate and final roll compaction products, as well as their interrelations. In order to do so, we have conducted a series of systematic experimental studies and utilized chemometric tools, such as design of experiments, latent variable models (i.e. PCA, OPLS and O2PLS) as well as mechanistic models based on the rolling theory of granular solids developed by Johanson (1965). More specifically, we have developed a modeling approach to elucidate the influence of different brittle filler qualities of mannitol and dicalcium phosphate and their physical properties (i.e. flowability, particle size and compactability) on intermediate and final product quality. This approach allows the possibility of introducing new fillers without additional experiments, provided that they are within the previously mapped design space. Additionally, this approach is generic and could be extended beyond fillers. Furthermore, in contrast to many other materials, the results revealed that some qualities of the investigated fillers demonstrated improved compactability following roll compaction. In one study, we identified the design space for a roll compaction process using a risk-based approach. The influence of process parameters (i.e. roll force, roll speed, roll gap and milling screen size) on different ribbon, granule and tablet properties was evaluated. In another study, we demonstrated the significant added value of the combination of near-infrared chemical imaging, texture analysis and multivariate methods in the quality assessment of the intermediate and final roll compaction products. Finally, we have also studied the roll compaction of an intermediate drug load formulation at different scales and using roll compactors with different feed screw mechanisms (i.e. horizontal and vertical). The horizontal feed screw roll compactor was also equipped with an instrumented roll technology allowing the measurement of normal stress on ribbon. Ribbon porosity was primarily found to be a function of normal stress, exhibiting a quadratic relationship. A similar quadratic relationship was also observed between roll force and ribbon porosity of the vertically fed roll compactor. A combination of design of experiments, latent variable and mechanistic models led to a better understanding of the critical process parameters and showed that scale up/transfer between equipment is feasible.

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Youssef, namnoum Carol. "Etude de l'influence des additions minérales sur l'auto-cicatrisation des matériaux cimentaires : caractérisation expérimentale et modélisation des propriétés visco-élastiques." Thesis, Ecole centrale de Nantes, 2021. http://www.theses.fr/2021ECDN0020.

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Les sollicitations mécaniques et environnementales subies par le béton peuvent entraîner l’apparition de fissures menaçant la durabilité des infrastructures. L’auto-cicatrisation, définie comme étant la capacité de refermeture des fissures sans intervention humaine, apparaît de plus en plus comme une solution prometteuse dans la durabilité des structures. Dans ce travail, l’intérêt s’est porté en premier lieu sur le processus physico-chimique de l’auto-cicatrisation autogène dans les mélanges composés de ciment et d’additions minérales de plus en plus utilisées dans l’objectif de diminuer l’empreinte carbone des bétons. Le potentiel de cicatrisation a été suivi sur différentes compostions en analysant leurs comportements mécaniques en flexion trois points. En parallèle, la nature chimique des produits formés au sein des fissures créées artificiellement a été suivi par différentes techniques d’analyses et d’imagerie microscopiques (MEB, DRX, ATG). L’interprétation fine des résultats a permis de dégager des conclusions claires sur la capacité de l’auto cicatrisation des matériaux et sur la minéralogie des produits de cicatrisation en fonction de la composition initiale. Dans un second temps, le comportement visco-élastique d’éprouvettes de mortier cicatrisées ou en cours de cicatrisation a été investigué. Il s’agit à notre connaissance d’un travail pionnier dans ce domaine dont l’objectif est de fournir des éléments de compréhension supplémentaires sur l’interaction entre la continuité d’hydratation du matériau cicatrisant et la présence d’un chargement mécanique. La démarche expérimentale a consisté à la fois dans le suivi du fluage en flexion de matériaux cicatrisés ainsi que leur comportement mécanique résiduel après déchargement. En combinant les deux résultats, nous avons conclu que l’aspect évolutif des propriétés mécaniques avec la continuité d’hydratation du ciment en cours de cicatrisation entraîne une relation entre les regains mécaniques et le taux de déformation de fluage. Puis, une modélisation à l’échelle microscopique a été établie pour identifier et évaluer les mécanismes physiques du couplage fluage-cicatrisation. Dans l’approche proposée, l’évolution des regains mécaniques par l’auto-cicatrisation des pâtes virtuelles a été simulée et a confirmé les hypothèses expérimentales de l’influence du regain mécanique sur le comportement différé des matériaux cicatrisés
The mechanical and environmental loads undergone by concrete can lead to cracking threatening the durability of infrastructure. Self-healing, defined as the ability of a structure to repair itself without human intervention, is increasingly emerging as a promising solution to increase the durability of structures. In this work, the focus was primarily on the physico-chemical process of autogenous self-healing for mixtures composed of cement and mineral additions increasingly used with the objective of reducing the carbon footprint of concrete. The healing potential has been evaluated on different compositions to analyze their mechanical behavior by three-point bending tests. In parallel, the chemical nature of the products formed within the artificially created cracks are monitored by various microscopic analysis and imaging techniques (SEM, XRD, TGA). The detailed interpretation of the results allowed clear conclusions to be drawn on the self-healing capacity of the materials and on the mineralogy of the healing products depending on the initial composition. Secondly, the visco-elastic behavior of healed or healing mortars have been investigated. To our knowledge, this is pioneering work in this field whose objective is to provide additional elements on the interaction between the continuity of hydration of the healing material and the presence of mechanical load. The experimental approach consisted both in monitoring the flexural creep of healed materials as well as their residual mechanical behavior after unloading. By combining the two results, we concluded that the evolutionary aspect of the mechanical properties with the continuity of hydration of cement during healing leads to a relationship between mechanical regains and the rate of creep deformation. Then, a microscopic scale modeling has been established to identify and evaluate the physical mechanisms of the creep-healing coupling. In the proposed approach, the evolution of mechanical regains by self-healing of virtual cement pastes has been simulated and confirmed the experimental hypotheses of the influence of mechanical regains on the creep displacement of healed materials

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42

Ameli, Mostafa. "Heuristic Methods for Calculating Dynamic Traffic Assignment Simulation-based dynamic traffic assignment: meta-heuristic solution methods with parallel computing Non-unicity of day-to-day multimodal user equilibrium: the network design history effect Improving traffic network performance with road banning strategy: a simulation approach comparing user equilibrium and system optimum." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSET009.

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Les systèmes de transport sont caractérisés de manière dynamique non seulement par des interactions non linéaires entre les différents composants, mais également par des boucles de rétroaction entre l'état du réseau et les décisions des utilisateurs. En particulier, la congestion du réseau impacte à la fois la répartition de la demande locale en modifiant les choix d’itinéraire et la demande multimodale globale. Selon les conditions du réseau, ils peuvent décider de changer, par exemple, leur mode de transport. Plusieurs équilibres peuvent être définis pour les systèmes de transport. L'équilibre de l'utilisateur correspond à la situation dans laquelle chaque utilisateur est autorisé à se comporter de manière égoïste et à minimiser ses propres frais de déplacement. L'optimum du système correspond à une situation où le coût total du transport de tous les utilisateurs est minimal. Dans ce contexte, l’étude vise à calculer les modèles de flux d'itinéraires dans un réseau prenant en compte différentes conditions d’équilibre et à étudier l’équilibre du réseau dans un contexte dynamique. L'étude se concentre sur des modèles de trafic capables de représenter une dynamique du trafic urbain à grande échelle. Trois sujets principaux sont abordés. Premièrement, des méthodes heuristiques et méta-heuristiques rapides sont développées pour déterminer les équilibres avec différents types de trafic. Deuxièmement, l'existence et l'unicité des équilibres d'utilisateurs sont étudiées. Lorsqu'il n'y a pas d'unicité, la relation entre des équilibres multiples est examinée. De plus, l'impact de l'historique du réseau est analysé. Troisièmement, une nouvelle approche est développée pour analyser l’équilibre du réseau en fonction du niveau de la demande. Cette approche compare les optima des utilisateurs et du système et vise à concevoir des stratégies de contrôle afin de déplacer la situation d'équilibre de l'utilisateur vers l'optimum du système
Transport systems are dynamically characterized not only by nonlinear interactions between the different components but also by feedback loops between the state of the network and the decisions of users. In particular, network congestion affects both the distribution of local demand by modifying route choices and overall multimodal demand. Depending on the conditions of the network, they may decide to change for example their transportation mode. Several equilibria can be defined for transportation systems. The user equilibrium corresponds to the situation where each user is allowed to behave selfishly and to minimize his own travel costs. The system optimum corresponds to a situation where the total transport cost of all the users is minimum. In this context, the study aims to calculate route flow patterns in a network considering different equilibrium conditions and study the network equilibrium in a dynamic setting. The study focuses on traffic models capable of representing large-scale urban traffic dynamics. Three main issues are addressed. First, fast heuristic and meta-heuristic methods are developed to determine equilibria with different types of traffic patterns. Secondly, the existence and uniqueness of user equilibria is studied. When there is no uniqueness, the relationship between multiple equilibria is examined. Moreover, the impact of network history is analyzed. Thirdly, a new approach is developed to analyze the network equilibrium as a function of the level of demand. This approach compares user and system optimums and aims to design control strategies in order to move the user equilibrium situation towards the system optimum

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Bullock, Paul. "Seepage scald : a case study in southeastern New South Wales." Phd thesis, 1989. http://hdl.handle.net/1885/8557.

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Dryland salinity in Australia is usually subdivided into two categories, scald and saline seepage, however, the use of these terms has not been consistent. The existence of a groundwater discharge condition should form the basis for distinguishing different areas of dryland salinity, but areas both with and without this condition have been labelled as ‘scalds’. It is suggested that ’seepage scald’ and ‘dry scald’ be used to distinguish scalds with a groundwater discharge condition from those scalds without while retaining the descriptive qualities of the term ‘scald’. Further, it is suggested that soils labelled as saline seepages fall into the seepage scald category. This study addresses the problem of seepage scald in southeastern New South Wales. There is very little information concerning the soil and hydrological properties of these areas and a case study of the Yarralaw seepage scald was undertaken to answer questions concerning the scald’s location, the threat of scald expansion, possible offsite effects and the scald’s origin. The results of this study have application to a number of similar sites in southeastern New South Wales.

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Saramago, Artur Rafael Servo Nunes Duarte. "Tablets manufacturing – Direct Scale-up from Lab to Manufacturing Facilities." Master's thesis, 2020. http://hdl.handle.net/10362/113511.

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Nowadays, oral dosage forms are the preferred drug delivery route. Concerning tablets as drug delivery systems, some solubility and flowability problems often arise, which can be fixed by manufacturing amorphous solid dispersions (ASD) and/or tablets via granulation (wet or dry) techniques. In this work, HPMCAS and PVPVA, typically selected polymers for ASD production, were incorporated in a standard formulation suitable for a dry granulation process. Generally, the process consists of ASD manufacturing via spray drying (SD), intragranular blending, roller compaction (RC) (includes compaction and milling) or slugging and milling (laboratory), extragranular blend, and tableting. An RC model, based on Johanson’s rolling theory, for predicting the intragranular material solid fraction (SF) at the rolls minimum gap and calibrated from in-die data from compaction simulator, was validated by comparing with experimental data from SF estimation via throughput. Using different toolings and dwell time, the Lab slugging was not able to mimic the manufacturing facilities (MF) ribbons produced via RC. Even when comparing ribbons and tablets from a case-study project with low SD dispersion percentage incorporated, the same difference was observed. It was evaluated how RC parameters, namely compaction force, gap between the rolls, and milling step (lab or MF), affected the granules size distribution and flowability. In terms of flowability, both formulations yielded results within typical dry granulation categories. Also, the MF milling step was successfully simulated at the lab, by selecting the same milling tip speed. Compactability-Tabletability-Compressibility (CTC) profiles were generated to compare the impact of the different processing routes, lab or MF, on tablets’ properties. Regardless of the manufacturing parameters, PVPVA tablets, showed better tableting characteristics and plastic deformation, comparing to HPMCAS formulation. A scale-up methodology was proposed based on out-of-die compressibility profiles. This approach aims to eliminate, whenever possible, non-GMP tests, decreasing costs and expanding MF’s availability.

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Walker, Amelia Dean. "Development and Initial Validation of the Disavowal of Racial Bias Scale (DRB)." Thesis, 2018. https://doi.org/10.7916/D83X9Q28.

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While research suggests that blatant expressions of racism are on the decline, more subtle forms of bias persist (Dovidio & Gartner, 2004; Nosek, Banaji, & Greenwald, 2002). These biases can be automatic and unintentional, often occurring outside conscious awareness. Studies suggest that developing awareness is the first step to moderating discriminatory thoughts and behaviors (Divine & Monteith, 1993; Dovidio & Gaertner, 2004; Durrheim, Hook, & Riggs, 2009; Monteith & Voils, 1998). When White Americans are aware of their biases, they are more likely to adjust their attitudes and alter their behaviors. Crucially, when biases go unacknowledged, there are fewer opportunities to combat unintentional racism. As a result, the tendency to disavow racial biases demands scholarly attention. In order to further research in this area, a way of measuring awareness of racial bias is needed. The purpose of this dissertation was to develop and initially validate the Disavowal of Racial Bias Scale (DRB). A review of the research on racial bias helped generate 38 initial items. An empirical approach was then used to determine an optimal version of the scale. In Phase 1, an exploratory factor analysis (EFA) of data from 579 participants suggested a 2-factor model with a total of 24 items. The first factor was named Bias Examples because it included statements referring to specific examples of racial bias. The second factor was named Bias Existence because it included statements referring to the general phenomenon of racial bias. In Phase 2, a confirmatory factor analysis (CFA) of data from a second subsample of 579 participants was used to confirm the factor structure identified in Phase 1. Both subscales demonstrated high internal consistency, providing evidence of the DRB's reliability. Further psychometric evaluations provided evidence of convergent and discriminant validity. However, the 2-factor model did not appear to be reasonably consistent with the data as evidenced by a poor model fit. Although there are many promising aspects of the final 24-item DRB, more work is needed to make it a valid measure for future use. Limitations of this study and recommendations for future scale development in this area will be discussed.

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Kate, Okaekwu Chinenye. "Fungal and aflatoxin occurrence in small-scale processed dry foodstuffs sold at informal retail outlets in the Johannesburg metropolis, South Africa." Diss., 2019. http://hdl.handle.net/10500/26336.

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Fungal species and their mycotoxins are the most predorminant contaminants of dried agricultural products in sub-Saharan Africa (SSA) and the main species of fungi that can synthesize mycotoxins are Aspergillus, Fusarium and Penicillium. In Africa, aflatoxin is labelled as a great threat to human and animal health due to its high contamination levels reported of aflatoxins in foods. The aim of this study was to survey fungi and aflatoxin contamination of small-scale processed foodstuffs sold at informal retail outlets in the Johannesburg metropolis, South Africa. A total of 270 food samples (10 starch and legume based foods, 11 meat and fish based foods, 22 spices and local condiments, 14 dried fruits and vegetables) were collected from retailers; and analysed four (4) times in different seasons of spring, summer, autumn and winter. Out of the 270 samples analysed, only 27.8% were contaminated with fungal. Of all the six categories of foods analysed, roots and tubers (60.0%), nuts and seeds (40.0%), dried vegetables (37.1%), and the Meat and Insect foods (33.3%) respectively, had the most contaminated samples with fungal respectively. The least contaminated food groups were the fish foods (10.0%) and spices and local condiments (16.7%) respectively. Twenty percent of the 270 dried food analysed were contaminated by Aspergillus species out of which 61.1% of the contaminated samples had fungal counts above 103 cfu/g. Aspergillus niger was the most predominant Aspergillus species identified in all the categories of food samples analysed. Fruits and vegetables (24.4%) and the nuts and seeds (20.0%) food groups had the highest number of samples contaminated with aflatoxin. Peanut flour and Cardamom had the most incidence of aflatoxin. AFB1, AFB2 & AFG1 were the most prominent aflatoxin types recovered from the food samples. Almost all the food samples in which aflatoxin were identified had aflatoxin values above 10μg/ml.
Life and Consumer Sciences
M.Sc. (Life Science)

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47

Chintalapati, Manjusha. "Indels and large scale variation in archaic hominins compared to present day humans." 2018. https://ul.qucosa.de/id/qucosa%3A32595.

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48

Lin, Ming-Yeng. "The effect of vegetation and noise barriers on the dispersion and deposition of ultrafine particles." Diss., 2011. http://hdl.handle.net/10161/4974.

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Ultrafine particles (UFP) emitted by traffic have been associated with health risks for people living and working near major roadways. Studies have shown that people living in near-roadway communities experience higher risk of aggravated asthma, respiratory diseases and even childhood leukemia. Sharp concentration gradients of UFP have been reported near major highways with the concentration decreasing rapidly away from the road. Dispersion of UFP downwind of a road depends on many parameters, such as the atmospheric stability and wind speed. Presence of different structures such as noise barriers and vegetation can greatly influence the dispersion and downwind concentrations of UFP. These structures can block the traffic emissions and increase vertical mixing. In addition, vegetation can reduce UFP by deposition processes. Two sets of experiments were conducted in this thesis to investigate the effect of barriers on UFP deposition and dispersion.

The first set of experiments was performed in a wind tunnel facility to address UFP deposition to vegetation barriers solely. Two analytical models were proposed to characterize UFP dry deposition to vegetation measured during the wind tunnel experiment. The first model was derived from the filtration theory to explain UFP dry deposition to pine and juniper branches. The model agrees well with the experimental data indicating that pine and juniper branches can be treated as fibrous filters. The fiber diameters of pine derived from the experimental data were also similar to the physical diameters of pine needles; thus, providing further evidence that vegetation can be regarded as fibers. The second model was derived from the continuity equation and can predict the branch-scale dry deposition of UFP using conventional canopy properties such as the drag coefficient and leaf area density. Both models agree with the measurement results to within 20%.

The second set of experiments was done in three near-roadway environments to investigate the effects of barriers on the dispersion and dry deposition of UFP. We used mobile and stationary measurements to obtain the spatial and temporal variability of UFP. Both mobile and stationary measurements indicated that vegetation and noise barriers can reduce downwind UFP concentrations through dispersion and dry deposition by 20-60 %.

In conclusion, the effect of barriers on UFP dispersion and deposition has been characterized in this thesis. Two analytical models were also proposed from the wind tunnel experiments to characterize dry deposition and agreed well with the measurement results. The analytical model could benefit future climate and air quality models.

Dissertation

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49

Yu-Jie, Chen, and 陳禹傑. "VR-Lab: Room-scale Immersive VR-Learning System with Customized DRM based on Unity3D." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/u9h9nv.

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碩士
國立中央大學
資訊工程學系
104
In the year 2016, the new products launched by HTC, Oculus and SONY lead to the breakthrough of virtual reality, which is a huge step for the VR industry to enter the consumer market. According to IDC, a market research organization, it is estimated that the sales of VR equipment in 2016 will exceed 9 million. And the output value will reach 3 billion by year 2020. Nowadays, the main stream of VR development are game industry and media entertainment industry. Minority is used in education. However, in the early stages, VR has been used as pilot-training. In one particular training, the Immersive first perspective of VR is really helpful. For instance, war practice, architecture design, medical surgery, and flight simulation. VR also contributes to education, where it can provide more possibility. By using VR, MOOCS can make people feel as if they were right in the scene. Furthermore, it allows students from all over the world to discuss "vis a vis.” In this paper, I’ll present you a virtual laboratory made by Unity3D, which enable primary school students to make physical and chemical experiments at high school level. Since the process of experiments requires accurate hands movements as well as accurate footsteps, we chose HTC vive for its Room-scale VR tracking function, which can provide a friendlier user experience. In addition, we implement customized digital rights management system. This system protects digital teaching material efficiently, and at the same time at the authorization term. Therefore, without the authority, no one has the access to the services-ensuring the rights and interest of firms.

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50

Wu, Tzung-Chieh, and 吳宗杰. "Correlation Between the Combustion Performance Indices-DRE,CE and PICs in a Laboratory Scale Spouted Bed Incinerator." Thesis, 1997. http://ndltd.ncl.edu.tw/handle/28843160026758857076.

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碩士
國立屏東技術學院
環境工程技術研究所
85
AbstractIncineration is one of the most efficient disposal processes to treat Incineration is one of the most efficient disposal processes to treatme red stream.An obvious advantage of incineration is the large mass and volumessions have found in the exhaust stream of incinerator. The major concern regarding organic emissions from hazardous waste incineration system is to form the products of incomplete combustion(PICs). DRE( Destruction and Removal Efficiency) of POHCs(Principal of Organic Hazardous Constituents) and CE(Combustion Efficiency)are the representative indices to evaluate the performance of incineration system. The correlations between DRE of POHCs, CE and the formation and destruction of PICs are investigated in this study.A laboratory scale incinere stabil ty under the designed operating conditions. These advantages stimulate the application of a laboratory scale combustor to investigate the key operating parameters related to the treatment performance in terms of CE, DRE of POHCs as well as the PICs. The spouted bed combustor employed in this study is a cone-shaped all-quartz reactor. The reaction is uninsulated so as to faciliate visual observation of the phenomena inside the combustor. Flue gas samples for DRE and PICs analysis are drawn continuously from the desired locations. After pretreatment, samples are injected into the GC/MSD and GC/FID to identify and quantify compounds. The basic gas measurements from combustor including O2, CO2 ,CO ,SOx, NOx is made with Flue Gas Analyser.Experimental results indicate that the concentration of CO near the wall of reactor is higher than it appears at the center of reactor. The effects are possibly caused by the physical mixing level and the residence time distribution. It suggests that the residence time scale of flue gas and the characteristics of PICs must be considered when using the DRE of POHCs to evaluate the incineration performance. Due to imperfect mixing, the PICs have the possibility to be produced in the pyrolysis pocket region. These by-products are highly dependent on the characteristics of fuel and the combustion operating parameters(ie, equivalence ratio, bed temperature---etc.). The results from our laboratory investigations have presented evidence that both physical mixing and chemical kinetics could interpret several reaction pathways in the PICs scheme.

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