Dissertations / Theses on the topic 'Moisture content'
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Amjad, Muhammad. "Seed irradiation in relation to moisture content." Thesis, University of Salford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281596.
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Vikberg, Tommy. "Moisture content measurement in the wood industry." Licentiate thesis, Luleå tekniska universitet, Träteknologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18148.
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In the wood industry, determination of the moisture content (mc) with a highaccuracy is of great importance. The green mc is important for optimisation of thewood drying process at sawmills, whereas the mc of dried boards is of interest for thefurther processing and final use of the boards. In the first publication in this thesis,which is a technical report written in Swedish, different measuring techniques withtheir own pros and cons are discussed. A total of 13 different measurement principlesare discussed, focusing on the ability to measure mc in the range of 7-18%. The resultsuggests that mc-meters that use electromagnetic waves in the radio- and microwaveranges have the greatest potential to become the next generation mc-meters for driedboards.The second publication, which is presented in this thesis, investigates the possibilityof measuring the green sapwood mc in pine logs by combining industrial X-rayscanners and 3D-scanners. The method is shown to be suitable for identifying batchesof logs in which the sapwood has begun to dry prior to sawing, rather than predictingthe sapwood mc with high accuracy at the level of individual logs.In a single board, one would ideally like to measure the mc profile over the entirecross section to determine the mc gradient. However, the measured result is affectedin the vicinity of the board edges. In the third publication, the existence of thisproblem is identified, and it is shown that it can be decreased by using correlationfunctions generated by finite element simulations of the measurement system.The fourth publication considers the potential to increase the measurement accuracyof the mc of single boards by combining different measurement techniques.Microwaves, X-rays and visual sorting into different wood quality classes are used. Itis shown that the measurement accuracy is increased by the addition of both the Xraymeasurements and the visual sorting. This result is interesting because visualsorting is usually already present in the final sorting of large sawmills. This is alsowhere the mc measurement preferably is to be performed.Godkänd; 2012; 20120315 (tomvik); LICENTIATSEMINARIUM Ämnesområde: Träfysik/Wood Physics Examinator: Professor Tom Morén, Institutionen för teknikvetenskap och matematik, Luleå tekniska universitet Diskutant: Teknologie licentiat Björn Källander, Stora Enso Timber AB, Falun Tid: Torsdag den 26 april 2012 kl 10.00 Plats: Hörsal A, Campus Skellefteå, Luleå tekniska universitet
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Nyström, Jenny. "Rapid measurements of the moisture content in biofuel." Doctoral thesis, Mälardalens högskola, Institutionen för samhällsteknik, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-130.
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An increasing number of power plants in Scandinavia are beginning to use biofuel instead of coal or oil. The material in the new fuel is a mixture of woodchips, mostly Pine, Spruce and Salix, bark, GROT (tops and branches from felling waste) and sawdust from sawmills. It is heterogeneous, having a moisture content varying from 15% up to 65%. The moisture content affects the combustion of the fuel and therefore its commercial value. The industry is now interested in obtaining a method for measuring the moisture content of biofuel, quickly and reliably; preferably on delivery at the power plant. The measuring technique presented in this thesis is the first reported in the literature capable of measuring the moisture content of a large sample of such an heterogeneous material as biofuel. The equipment is today calibrated for a sample volume of 0.1 m3. A radio frequent signal is supplied from an antenna and penetrates the biofuel. Its reflection is modeled using partial least squares. As part of the work presented in this thesis, a new type of measuring rig and an analysis method for measurement of the moisture content of large samples of heterogeneous material have been developed. A statistical model for moisture content measurements of five different biofuel materials using radio waves has been built, having a root mean square error of prediction of 2.7. The interactions between biofuels and radio frequent signals have been demonstrated, indicating a variation of the reflection with varying types of biofuel material and variation in the reflection and delay of the signal with varying moisture content.
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Jonsson, Ivar Mar. "Estimation and identification of moisture content in paper." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/29989.
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The purpose of this thesis is to summarize some results obtained for an improved moisture estimation and identification algorithm which extracts, the cross direction (CD) moisture profiles and machine direction (MD) moisture variations from the composite measured profile, in the presence of noise. The objective is to use the algorithm as part of a paper machine control system to maintain the moisture content of the sheet at a target value and keep a uniform cross-sectional profile shape. The estimation and identification scheme is based upon a nonlinear model, and consists of a modified least squares algorithm for estimating cross direction profile deviations and a Kalman filter for estimating machine direction variations and disturbances. The scheme, when tested on simulated data where the true profiles are known, is shown to give robust and effective results. Off-line testing of the algorithm on industrial data is also presented. Results from the on-line application of the algorithm working in closed loop in the industry are also included. Future work will consist of further industrial testing along with fine-tuning. The final objective is then to have this algorithm integrated in an overall paper machine control system, where other variables, such as basis weight and caliper, are estimated and controlled.Applied Science, Faculty of
Electrical and Computer Engineering, Department of
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Jung, Sarah. "Sulphide self-heating: moisture content and sulphur formation." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114249.
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Spontaneous or self-heating of sulphides can occur under certain conditions of moisture, temperature and oxygen concentration. This can lead to emission of toxic gases such as SO2 and if uncontrolled, to ignition. Research has established that self-heating divides into three stages: A (below 100 oC), B (above 100 oC) and C (above 350 oC). The understanding is that conditions in stage A promote oxidation of sulphides to elemental sulphur which in stage B oxidizes to SO2. A standard test based on air injections is used to measure stage A and stage B self-heating. In this thesis, a mitigation method using hygroscopic reagents to control moisture has been tested on a pyrrhotite-rich material. Water retention capacity was determined to select reagents for application in the standard self-heating test. Tests showed that the water retention capacity correlated with mitigation of self-heating. Two reagents that showed the best mitigating effect were silica gel and poly (acrylic acid sodium salt).It is hypothesized that temperature and relative humidity have an effect on elemental sulphur production in stage A. To test, pyrrhotite (Fe1-xS) samples were exposed (weathered) at temperatures of 40 oC and 60 oC and relative humidities of 100%, 70% and 30% for 31 days. The weathering apparatus and sulphur analysis method are described. At the end of weathering (31 days), samples were subjected to stage B self-heating test. Self-heating rate and total number of air injections until heating ceased were determined. Both measurements showed that sulphur formed at 40 oC in stage A gave higher heating response than sulphur formed at 60 oC. This observation raises two possibilities that are discussed: there are different types of sulphur formed at the two temperatures; and there is a factor other than just sulphur content that controls stage B self-heating.L'autochauffage spontané des sulfures peut se produire sous certaines conditions d'humidité et d'oxygène. Cela peut entraîner l'émission de gaz toxiques tel que le SO2. Si l'autochauffage n'est pas contrôlé, la combustion peut se produire spontanément. La recherche a établi que l'autochauffage se divise en trois étapes, soit : l'étape A (en dessous de 100 oC), l'étape B (plus de 100 oC) et l'étape C (plus de 350 oC). Nous comprenons que l'oxydation des sulfures en soufre élémentaire survient lors de l'étape A. Le soufre élémentaire s'oxyde pour produire le SO2 dans l'étape B. L'autochauffage lors des étapes A et B est mesuré en utilisant un test standard qui injecte l'air dans les échantillons.Dans ce mémoire, la méthode testée pour l'atténuation des sulfures autochauffantes consistait à contrôler l'humidité en utilisant des produits hygroscopiques sur des échantillons riches en pyrrhotite. Le facteur de sélection des produits hygroscopiques utilisés lors des tests d'autochauffage était leur capacité de rétention d'eau. Les tests ont montré qu'il y a une corrélation entre la rétention d'eau et l'atténuation d'autochauffage. Le gel de silice et le polymère superabsorbant ont montré le meilleur effet d'atténuation. L'hypothèse émise était que la température et l'humidité relative ont un effet sur la production de soufre élémentaire lors de l'étape A. Pour vérifier l'hypothèse, l'échantillon de pyrrhotite (Fe1-xS) était exposé (érodée) à des températures de 40 oC et 60 oC et à une humidité relative de 100%, 70%, 30% pendant 31 jours. L'appareil d'érosion et la procédure d'analyse de soufre ont été décrits dans ce document. Suite à l'étape A (31 jours), les échantillons étaient soumis lors de l'étape B à un test d'autochauffage. Le taux d'autochauffage et le nombre total d'injections d'air avant que le chauffage cesse ont été déterminés. Les deux mesures ont démontré que le soufre qui est formé à 40 oC lors de l'étape A a donné une réponse de chauffage plus élevée que le soufre qui est formé à 60 oC. Cette observation permet de conclure à deux possibilités qui seront discutées : premièrement, des types de soufre différents se forment aux deux températures et deuxièmement, il y a un autre facteur d'autochauffage que la formation de soufre qui contrôle l'étape B.
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Hague, James R. B. "Effect of moisture content changes on wood creep." Thesis, Bangor University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358374.
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Gorthi, Swathi. "Prediction Models for Estimation of Soil Moisture Content." DigitalCommons@USU, 2011. https://digitalcommons.usu.edu/etd/1090.
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This thesis introduces the implementation of different supervised learning techniques for producing accurate estimates of soil moisture content using empirical information, including meteorological and remotely sensed data. The models thus developed can be extended to be used by the personal remote sensing systems developed in the Center for Self-Organizing Intelligent Systems (CSOIS). The dfferent models employed extend over a wide range of machine-learning techniques starting from basic linear regression models through models based on Bayesian framework. Also, ensembling methods such as bagging and boosting are implemented on all models for considerable improvements in accuracy. The main research objective is to understand, compare, and analyze the mathematical backgrounds underlying and results obtained from dfferent models and the respective improvisation techniques employed.
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Haigh, Arthur D. "A study of microwave moisture measurement in bulk materials." Thesis, Manchester Metropolitan University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387247.
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Moisture measurements play an important role in many material preparations and industrial processes. Microwave techniques have been used for several decades for such measurements. Shortcomings associated with the method have been addressed. Graphical solutions used hitherto to obtain the permittivity from waveguide measurements have been replaced by computer programs. The accuracy of measurement have been improved by the development of waveguide standards and the implementation of calibration procedures. Permittivity measurements in through and short circuited rectangular waveguides are reported on a wide range of solid, granular and liquid materials important to the food industry. Techniques to suppress standing wave effects have enabled accurate plane wave measurements of permittivity. For bulk materials, new measurement probes have been developed for on line measurements and associated with these probes lower cost instrumentation has been considered. The· main outcome of the study is the improvement in permittivity measurements of sample quantities of material. Moisture measurements in bulk materials have been facilitated by novel non invasive probes.
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van, Dyk Hermanus H. "Ultrasonic Evalutation of Defects and Moisture Content of Lumber." Fogler Library, University of Maine, 2004. http://www.library.umaine.edu/theses/pdf/vanDykHH2004.pdf.
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Manchikanti, Ujwala. "Evaluation of microwave sensor for soil moisture content determination." [Ames, Iowa : Iowa State University], 2007.
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Björnsdóttir, Jóhanna Eir, and Jóhann Björn Jóhannsson. "Moisture Content and Mould Risk in Concrete Outer Walls." Thesis, KTH, Byggnadsteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-231391.
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Previous studies on the typical Icelandic external wall have shown thatcondensation occurs at the interior surface of the concrete and field inspectionshave supported this conclusion. The primary objective ofthis study is to analyse the hygrothermal behaviour of the typical Icelandicwall and evaluate the mould risk at the interior surface of theconcrete.A comparative study is performed to compare the hygrothermalperformance and mould growth risk of two concrete outer wall structureswith interior and exterior insulation, by performing a parametricstudy using the simulation program WUFI® Pro.Additional parametric studies are performed in order to analyse theeffect of various material properties of the Icelandic building materialson the hygrothermal behaviour of the wall. This part also utilizedWUFI® Pro.To investigate the thermal bridge of the Icelandic wall, simulationswere conducted with the COMSOL Multiphysics software to evaluatethe linear thermal bridge and the risk of condensation at the joint.Lastly, an experiment was set up at the Innovation Center Iceland tomodel the interior insulated wall-slab section. The experimental setupwas completed during this time but the results will be analysedfurther after the thesis work.The results from this study indicate that the typical Icelandic wall ismore sensitive to rain than to interior moisture load and that no condensationoccurs within the wall structure. As concrete is inorganic,the risk of mould growth in the wall structure is limited, however,with increased driving rain load the mould risk increases. The resultsalso revealed that the moisture content of the interior insulated wallwas a great deal higher compared to the exterior insulated wall. Furthermore,the humidity level at the interior surface of the concrete inthe interior insulated wall exceeded the recommended critical humiditylevel based on general suggestions. Finally, results indicated thatusing a more dense concrete resulted in higher relative humidity at theinterior surface but a lower total water content of the wall.
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Hamidisepehr, Ali. "CLASSIFYING SOIL MOISTURE CONTENT USING REFLECTANCE-BASED REMOTE SENSING." UKnowledge, 2018. https://uknowledge.uky.edu/bae_etds/57.
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The ability to quantify soil moisture spatial variability and its temporal dynamics over entire fields through direct soil observations using remote sensing will improve early detection of water stress before crop physiological or economic damage has occurred, and it will contribute to the identification of zones within a field in which soil water is depleted faster than in other zones of a field.
The overarching objective of this research is to develop tools and methods for remotely estimating soil moisture variability in agricultural crop production. Index-based and machine learning methods were deployed for processing hyperspectral data collected from moisture-controlled samples.
In the first of five studies described in this dissertation, the feasibility of using “low-cost” index-based multispectral reflectance sensing for remotely delineating soil moisture content from direct soil and crop residue measurements using down-sampled spectral data were determined. The relative reflectance from soil and wheat stalk residue were measured using visible and near-infrared spectrometers. The optimal pair of wavelengths was chosen using a script to create an index for estimating soil and wheat stalk residue moisture levels. Wavelengths were selected to maximize the slope of the linear index function (i.e., sensitivity to moisture) and either maximize the coefficient of determination (R2) or minimize the root mean squared error (RMSE) of the index. Results showed that wavelengths centered near 1300 nm and 1500 nm, within the range of 400 to 1700 nm, produced the best index for individual samples; however, this index worked poorly on estimating stalk residue moisture.
In the second of five studies, 20 machine learning algorithms were applied to full spectral datasets for moisture prediction and comparing them to the index-based method from the previous objective. Cubic support vector machine (SVM) and ensemble bagged trees methods produced the highest composite prediction accuracies of 96% and 93% for silt-loam soil samples, and 86% and 93% for wheat stalk residue samples, respectively. Prediction accuracy using the index-based method was 86% for silt-loam soil and 30% for wheat stalk residue.
In the third study, a spectral measurement platform capable of being deployed on a UAS was developed for future use in quantifying and delineating moisture zones within agricultural landscapes. A series of portable spectrometers covering ultraviolet (UV), visible (VIS), and near-infrared (NIR) wavelengths were instrumented using a Raspberry Pi embedded computer that was programmed to interface with the UAS autopilot for autonomous reflectance data acquisition. A similar ground-based system was developed to keep track of ambient light during reflectance target measurement. The systems were tested under varying ambient light conditions during the 2017 Great American Eclipse.
In the fourth study, the data acquisition system from the third study was deployed for recognizing different targets in the grayscale range using machine learning methods and under ambient light conditions. In this study, a dynamic method was applied to update integration time on spectrometers to optimize sensitivity of the instruments. It was found that by adjusting the integration time on each spectrometer such that a maximum intensity across all wavelengths was reached, the targets could be recognized simply based on the reflectance measurements with no need of a separate ambient light measurement.
Finally, in the fifth study, the same data acquisition system and variable integration time method were used for estimating soil moisture under ambient light condition. Among 22 machine learning algorithms, linear and quadratic discriminant analysis achieved the maximum prediction accuracy.
A UAS-deployable hyperspectral data acquisition system containing three portable spectrometers and an embedded computer was developed to classify moisture content from spectral data. Partial least squares regression and machine learning algorithms were shown to be effective to generate predictive models for classifying soil moisture.
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Jazayeri, Sina. "Measurement and monitoring of moisture content in timber and investigations of moisture gradients using dielectric measurements." Thesis, University of Bedfordshire, 1999. http://hdl.handle.net/10547/622156.
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This thesis addresses various issues in connection with the measurement of moisture content in timber. The early parts include long term experimentally based studies which culminated in producing recommendations to existing British Standards for equilibrium moisture content (EMC) of timber in internal environments. Findings consistently showed lower EMCs than existing recommended values; these are believed to be caused by socio-economic factors. Intermediate sections of the thesis continue with tests on electrical methods of moisture content measurement to establish a basis for comparability and the claimed accuracy of currently available moisture meters in the market. To this end, the performance of a wide range of resistance-type moisture meters in worldwide use was critically investigated under laboratory conditions - it was established that even under the strict controlled conditions of the study, large discrepancies are not uncommon (as great as 13% moisture content difference was observed). While some instruments consistently underestimated, others overestimated under identical conditions. Lack of agreed standards for species corrections and temperature correction factors were found to be the main cause of disagreement between the meters. Further discussions include the layout for a proposed standard in which agreed values for species and temperature correction factors would be established. In the latter part of the thesis moisture gradients in timber, the causes and the current methods of assessment are discussed. In particular, the performance of a leading brand capacitance-type moisture meter was systematically investigated both in the absence and in the presence of predetermined moisture gradients. It was established that moisture gradients severely affect the measured moisture content. A computer controlled capacitance measurement system based on resonance detection was developed to initially replicate the behaviour of conventional capacitance-type moisture meters, and to further investigate possible moisture gradient detection protocols. Two electrode designs were used in order to investigate methods by which moisture gradients could be detected. It was shown that a multi-plate electrode can be used to detect moisture gradients in timber to depths of at least 10 mm.
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Rosenkilde, Anders. "Moisture content profiles and surface phenomena during drying of wood." Doctoral thesis, KTH, Civil and Architectural Engineering, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3456.
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Timber drying is one of the most important processes whenmanufacturing sawn timber products. The drying processinfluences deformations, surface checking, discoloration andhence, the product quality and the manufacturing costs.Research in this field is of great importance for the woodindustry since the industrial drying process always needs to beimproved as market demands increases and new wood products aredeveloped.
The aim of the present thesis was to investigate themoisture transport behaviour in wood based on measurementsduring drying from fresh condition down to end use moisturecontent. The behaviour near the surface interface has beenspecifically investigated since it is of great importance forthe theoretical description of the drying process. Furthermore,studies based on measurements in the wood surface layer duringdrying are not easy to find in the literature. The reason forthat is probably that it is very difficult to make accuratemoisture measurements with high spatial or temporal resolutionwithout disturbing the drying process.
Measurements of moisture content profiles in Scots pineheartwood and sapwood during drying have been performed byusing three different methods. The first was a destructivemethod where the wood samples are sliced with a knife intoseveral smaller pieces. The moisture content in each piece wasdetermined with the dry weight method. The second method usedis non-destructive and it utilises a medical CT-scanner thathas been adapted for drying experiments. The samples are driedin-situ the scanner through the whole experiment. TheCT-scanner measures density and the moisture content arecalculated according to existing methods developed by otherscientists. The third method was also non-destructive and itutilises a Magnetic Resonance Imaging, MRI, technique. Withthis technique the amount of water in the wood sample ismeasured directly even though it has to be calibrated tomoisture content.
The surface emission factor, S, or surface resistance, 1/S,has been studied by performing sorption experiments with MDF ina narrow moisture content range. The experiment was evaluatedusing a simple diffusion model that includes a surface emissionfactor S. The experimental result was compared with resultscalculated using well established boundary layer theories.
Measurements of moisture content profiles in the wood bulkshowed an expected Fickian behaviour at moisture contents belowthe fibre saturation point. Above the fibre saturation pointalmost flat moisture profiles were observed. This behaviour wasnot expected and it is not possible to simulate this behaviourwith the existing drying models since they usually assume thatthere is a gradient in the moisture profile over the wholemoisture content range. From the moisture profiles thediffusion coefficients were determined over a moisture contentranging from 8 to 30%. The values for heartwood and sapwood areapproximately equal in radial and tangential direction tograin. Furthermore, the diffusion values in longitudinaldirection are much higher as expected.
The sorption experiments with MDF gave a greater surfaceresistance compared with the calculation that was based onboundary layer theory. The ratio was three or higher. Thisimplied that there was a greater resistance in the surfacelayer. In addition, this was not well described in theliterature even though a few recent published studiesexist.
High resolution measurements in the surface layer of woodshowed behaviour similar to that observed in the bulk wood. Theresults showed the very early development of a dry zone closeto the surface interface. In that zone or shell the moisturecontent was below the FSP even though the bulk moisture contentwas far above the FSP. At the end of the experiments themoisture content in the surface layer (0300 µm)nearly reached the equilibrium moisture content even though thebulk moisture content still was much higher.
Keywords:Computer tomography, Diffusion, Magneticresonance, Moisture measurements, Moisture profiles, Surfaceemission, Wood drying
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Hong, Bei, and Bei Hong. "Effect of moisture content on voc transport in unsaturated media." Thesis, The University of Arizona, 1994. http://hdl.handle.net/10150/626779.
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Liu, Ziyang. "Prediction of Soil Layer R-Value Dependence on Moisture Content." PDXScholar, 2011. https://pdxscholar.library.pdx.edu/open_access_etds/125.
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This study focuses on how green roof thermal performance is affected by the soil moisture in summer condition. It aims to determine whether moist soil is a better insulator during the summer months than dry soil. A soil model is developed to predict simultaneous conduction, convection, and surface evaporation for a layer of moist soil representing a green roof. It used to analyze evaporation process and its affect on the soil resistance. The model considers only bare soil without vegetation on the roof. The model predicts the soil surface temperature as it is affected by soil moisture content, which can then be used to calculate heat transfer through the soil layer. An experimental dry out test was conducted to measure the soil moisture and soil temperature histories. Comparison of the predicted and measured sol surface temperature shows that the model reasonably captures the actual behavior. The evaporative cooling effectively reduces the soil surface temperature and heat flux in moist soil and can be used as an effective way to insulate the roof.
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Diefenderfer, Brian Keith. "Moisture Content Determination and Temperature Profile Modeling of Flexible Pavement Structures." Diss., Virginia Tech, 2002. http://hdl.handle.net/10919/27492.
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A majority of the primary roadways in the United States are constructed using hot-mix asphalt (HMA) placed over a granular base material. The strength of this pavement system is strongly influenced by the local environmental conditions. Excessive moisture in a granular base layer can cause that layer to lose its structural contribution by reducing the area over which loading may be distributed. Excessive moisture and fine particles can be transported by hydrostatic pressure to the surface layers, thus reducing the strength of the overlying HMA by contamination. Moisture in the surface HMA layers can cause deterioration through stripping and raveling. In addition, as HMA is a viscoelastic material, it behaves more as a viscous fluid at high temperatures and as an elastic solid at low temperatures. Between these two temperature extremes, a combination of these properties is evident. Thus, understanding the environmental effects on flexible pavements allows better prediction of pavement performance and behavior under different environmental conditions.
As part of the ongoing pavement research at the Virginia Smart Road, instrumentation was embedded during construction to monitor pavement response to loading and environment; moisture content of the granular base layers and temperature of the HMA layers were among the responses monitored. The Virginia Smart Road, constructed in Blacksburg, Virginia, is a pavement test facility is approximately 2.5km in length, of which 1.3km is flexible pavement that is divided into 12 sections of approximately 100m each. Each flexible pavement section is comprised of a multi-layer pavement system and possesses a unique structural configuration. The moisture content of aggregate subbase layers was measured utilizing two types of Time-Domain Reflectometry (TDR) probes that differed in their mode of operation. The temperature profile of the pavement was measured using thermocouples.
Data for the moisture content determination was collected and results from two probe types were evaluated. In addition, the differences in the moisture content within the aggregate subbase layer due to pavement structural configuration and presence of a moisture barrier were investigated. It was shown that the two TDR probe types gave similar results following a calibration procedure. In addition to effects due to pavement structure and subgrade type, the presence of a moisture barrier appeared to reduce the variability in the moisture content caused by precipitation. Temperature profile data was collected on a continuous basis for the purpose of developing a pavement temperature prediction model. A linear relationship was observed between the temperature given by a thermocouple near the ground surface and the pavement temperature at various depths. Following this, multiple-linear regression models were developed to predict the daily maximum or minimum pavement temperature in the HMA layers regardless of binder type or nominal maximum particle size. In addition, the measured ambient temperature and calculated received daily solar radiation were incorporated into an additional set of models to predict daily pavement temperatures at any location. The predicted temperatures from all developed models were found to be in agreement with in-situ measured temperatures.Ph. D.
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Avelar, Lezama Ivan. "Preliminary non-destructive assessment of moisture content, hydration and dielectric properties of Portland cement concrete." Thesis, Texas A&M University, 2005. http://hdl.handle.net/1969.1/4739.
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Moisture availability is a focal point in the structural development of young concrete. Under low humidity and hot weather conditions, concrete loses moisture rapidly as it hardens, and it is very difficult, if not impossible, to minimize this loss even though proper curing procedures are used. Early losses in moisture content jumpstart premature surface self-dissecation, increase surface paste porosity, prevent concrete from achieving the mechanical properties for which it was originally designed, and facilitate the development of surface distresses such as spalling. Curing effectiveness and structural assessment of young concrete is generally done through conventional destructive or invasive testing. However, there is no fully established non-destructive testing protocol to assess moisture content and its effects on concrete properties quantitatively in an on-site, fast, and non-invasive way. The possibility and feasibility of establishing a testing protocol with such attributes is explored. Previous research on pavement bases has used dielectric measurements to relate moisture content to their structural performance. Due to the high dielectric value of water as compared to any other material used in construction, it is possible to relate high volumetric water content to high dielectric readings. In this study, compressive strength tests combined with dielectric and mass measurements are used to investigate how dielectric properties change with hydration. The results of this study suggest that it may be possible to approximate the volumetric moisture content in concrete by measuring the dielectric value of concrete as it hardens.
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Uddin, MD Sharif. "Characterization and modeling of equilibrium moisture content (EMC) properties of wheat /." Search for this dissertation online, 2005. http://wwwlib.umi.com/cr/ksu/main.
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Pledger, Sean. "Simulation modeling of forest biomass operations and harvest residue moisture content." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/57858.
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In order to limit the effects of anthropogenic climate change the world is moving away from the use of fossil fuels as a primary energy source. Bioenergy is expected to form a substantial contribution to this transitional strategy. In order to increase bioenergy production, underutilized forest harvest residues are being targeted as a fuel source. Even with favorable policies in place to encourage their use, the processing and collection of these previously disregarded resources is often prohibitively expensive. Quality factors such as material moisture content also impact the viability of harvest residues for fuel purposes. As a result, careful operational planning is of great importance to sourcing high quality, economically feasible biomass. To gain a better understanding of the forest biomass supply chain, a simulation model was developed for a case study located in coastal British Columbia, Canada. A seasonal moisture content trend was identified and incorporated to help develop a strategy for sourcing high quality materials. It was found for BC’s coastal temperate rainforest environment that by delaying biomass collection until the second summer after timber harvest an average delivered moisture content of 28% can be achieved rather than 38% is operations proceed in the first summer. This reduction in delivered moisture content also led to a decrease in delivered cost from $72.08 to $67.95 per oven dried tonne. Trucking and equipment configurations were also examined to identify least cost approaches to biomass collection under varying conditions. Comparing high productivity and low productivity equipment configurations showed a $26.08/ODT cost increase when switching to less productive equipment. By employing an electric centralized grinder transporting unprocessed harvest residues, costs were shown to decrease for all cutblock groups with a cycle time of less than four and a half hours. Least cost fleet size was found to be largely dependent on the average cycle time to the biomass source. And the volume of available biomass at a given cutblock was found to have an impact on delivered costs with a 20% increase in biomass volume resulting in a cost decrease of greater than $2/ODT.Forestry, Faculty of
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Almoustafa, Turkia AbdAlkarem. "Optical remote sensing for estimating fuel moisture content in upland vegetation." Thesis, University of Salford, 2011. http://usir.salford.ac.uk/26538/.
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In the United Kingdom (UK) uncontrolled fires in upland moorlands have a negative effect on biodiversity, soil stability and nutrient dynamics. The control of these fires may be problematic because of the inaccessibility of the terrain. This research aims to investigate whether vegetation Fuel Moisture Content (FMC), a key variable influencing fire ignition probability and rate of fire spread, varies temporally and between species types in the UK uplands and whether FMC can be estimated using optical remote sensing. Ground-based measurements of vegetation variables, including FMC and spectral reflectance, were collected on a monthly basis from March 2008 to March 2009 for six study plots at Burbage Moor in the Peak District, United Kingdom. The FMC for the study plots was calculated and compared to the ground-based spectra directly, and correlated with first derivative and narrow-band vegetation indices. FMC was found to vary temporally and with vegetation type. Reflectance variability with FMC was strongest in the near infrared and shortwave infrared regions. The correlation between reflectance and FMC was higher when the first derivative and narrow-band vegetation indices and in particular Moisture Stress Index (MSI) were used. To extrapolate the results to a landscape scale, two hyperspectral images, for May 6 th and July 1 st 2008, were obtained by the Natural Environment Research Council Airborne Research and Survey Facility (NERC ARSF). Concurrently with the flights, in-situ field measurements were made. With the airborne data, the strength of the relationships between FMC and the spectral data sets were also explored using linear regression. Results from the airborne data confirm the results of ground-based measurements in terms of reflectance variability with FMC and in terms of the strength of the spectral correlation with FMC, FMC correlation with the first derivative and FMC correlation with narrow-band vegetation indices. Within the airborne data, the broad band MSI, which was calculated based on the spectral wavebands of Landsat ETM, was also found to have a significant correlation with FMC. This relationship, which was unknown before the current study was performed, offers the potential for operational application of remotely sensed data for FMC estimation at landscape scales. The implication of this is that remote sensing could have a role in timely mapping of fire risk for large areas of moorland.
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Wealleans, Heidi. "Characterisation of the moisture content and growth of donkey hoof horn." Thesis, De Montfort University, 2008. http://hdl.handle.net/2086/4262.
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Feghi, Abduessalam. "Moisture content and resistance to radiation stress in three seed species." Thesis, University of Salford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265801.
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Mugabi, Paul. "Moisture content and drying defects in kiln-dried Eucalyptus grandis poles." Thesis, Stellenbosch : Stellenbosch University, 2007. http://hdl.handle.net/10019.1/4575.
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Thesis (PhD (Forest and Wood Science))--Stellenbosch University, 2007.ENGLISH ABSTRACT: There has been a reported reduction in the durability of creosote treated, wooden utility poles in South Africa in recent years. Several factors could have been responsible for this. In this study, Eucalyptus grandis pole drying schedules currently used, methods of measurement of moisture content (MC) after drying and drying defects were investigated. Relationships involving drying defects and MC gradient before treatment which may help in the development of simple nondestructive methods of assessing defects such as surface checking, honeycomb and collapse, and MC gradient were also explored. The long term goal of this study was to increase the durability of treated poles by avoiding unacceptable drying defects and MC values before treatment. The results of this investigation are presented in the following chapters: an introduction motivating the aims of the investigations (Chapter 1); a review of literature relevant to MC and drying defects in sawn or round wood (Chapter 2); ready for press manuscripts on MC and drying defects in kiln-dried E. grandis poles (Chapters 3 to 7) and a general conclusion that links up chapters 3 to 7, and recommendations (Chapter 8). The auger drill method gave reliable MC values when samples in increments of 25 mm depths into the pole were taken. However, when single samples of 50 mm and 75 mm depths were considered, the auger drill MC measurements were unreliable. It was concluded that SABS SM 983 (2000), which specifies taking single radial auger drill samples of depth 70±5 mm at pole mid length, is not a reliable method of measuring MC in a kiln-dried E. grandis pole. Correlation results indicated that tree growth factors such as sapwood depth, green MC and heartwood percentage were related to final drying defects and may be used as criteria for pole sorting before kiln drying. Also, the number of valleys per unit length (VPUL) of the circumference at the theoretical ground line (TGL) was positively correlated with honeycomb and closed surface checks, implying that VPUL as a parameter of the pole circumference profile can be used to assess invisible, internal defects. The dry bulb temperature (Tdb) of 80oC, used to dry poles in industry, was too high and resulted into unacceptable levels of drying defects in kiln dried E. grandis poles. In addition, the drying period of 8 days was too short to attain an acceptable MC gradient in poles. It is, therefore, recommended that: To use the auger drill method to reliably determine the moisture content of a pole, samples in increments of 25 mm should be taken. MC measurements should be made at the most critical zones of a pole such as the TGL and not higher up since there is normally considerable MC variation in the longitudinal direction. It is also important to consider sampling more than one position on the pole circumference to cater for the MC variation in the tangential direction. For poles with large sapwood depths i.e. >15mm, mild drying conditions at the beginning of a drying run should be used, since such poles may be more susceptible to surface checking. Poles with large heartwood percentages should also be dried with suitable kiln schedules, i.e. with low Tdb to minimise honeycomb and collapse. In general, Tdb lower than 80oC should be considered in order to reduce the defects to acceptable levels. Poles should be dried for longer than 8 days even at Tdb as high as 80oC to reduce the MC to acceptable values and gradients. Since only three schedules were tested, more drying schedules should be investigated to make reliable conclusions about the effect of schedule on drying defects. In addition, more poles per schedule should be considered in order to obtain statistically reliable results. The relationship of pole diameter and drying defects also requires further investigation. Since a limited sample was used to test for the effect of source of poles and drying schedules on defect correlations, further studies should be done on sufficient samples to come up with more reliable conclusions. It is also necessary to further investigate the possible variation in correlation of VPUL and internal defects on a large sample of poles from specific sources and drying schedules.
AFRIKAANSE OPSOMMING: Die afgelope paar jaar is waargeneem dat kreosootbehandelde transmissiepale 'n afname in duursaamheid toon. Verskeie faktore kan hiervoor verantwoordelik wees. In hierdie studie is huidige Eucalyptus grandis oonddrogingskedules en voggehalte- (VG) bepalingsmetodes vóór en na droging asook drogingsdefekte ondersoek. Verwantskappe tussen drogingsdefekte en VG-gradiënt vóór behandeling wat kan meehelp om nie-destruktiewe metodes te ontwikkel om defekte soos oppervlaktekrake, interne barste en instorting en VG-gradiënt te bepaal, is ook bestudeer. Die langtermyn doelwit van hierdie studie is om die duursaamheid van behandelde pale te verbeter deur onaanvaarbare drogingsdefekte en voggehaltes vóór behandeling te vermy. Die resultate van hierdie ondersoek word in die volgende hoofstukke bespreek: 'n inleiding waarin die doelwitte van die onderskeie ondersoeke motiveer word (Hoofstuk 1); 'n oorsig van die literatuur relevant tot VG en drogingsdefekte in gesaagde en rondehout (Hoofstuk 2); persklaar manuskripte oor VG en drogingsdefekte in oondgedroogde E. grandis pale (Hoofstukke 3 tot 7) en 'n algemene gevolgtrekking wat bevindings uit hoofstukke 3 tot 7 saamvat gevolg deur aanbevelings (Hoofstuk 8). Die augerboor-metode kon betroubare VG-waardes lewer indien monsters van 25mm diepteinkremente in die paal geneem is. Augerboor-voggehaltemetings met enkel 50mm en 75mm monsters was egter onbetroubaar. Daar is bevind dat SABS SM 983 (2000), wat 'n enkel radiale augerboormonster tot op 'n diepte van 70±5 mm in die middel van die lengte van die paal spesifiseer, nie 'n betroubare VG-bepalingsmetode vir oondgedroogde E. grandis pale is nie. Die resultate het aangetoon dat boomgroeifaktore soos spinthoutdiepte, groen voggehalte en die persentasie kernhout aan drogingsdefekte verwant is en as basis vir sortering van pale vóór oonddroging gebruik kan word. Ook kon die aantal valleie per eenheidslengte (e. VPUL) van die omtrek by die teoretiese grondlyn (TGL) positief met interne barste en geslote oppervlaktekrake korreleer word wat impliseer dat VPUL as parameter van die omtrekprofiel van die paal gebruik kan word om onsigbare, interne defekte mee vas te stel. Die droëbaltemperatuur (Tdb) van 80oC wat in die industrie gebruik word, was te hoog omdat dit onaanvaarbare vlakke van drogingsdefekte in oondgedroogde E. grandis veroorsaak het. Daarbenewens was die drogingsperiode van 8 dae by 'n Tdb van 80oC te kort om 'n aanvaarbare VG-gradiënt te lewer. Die volgende word derhalwe aanbeveel: Om betroubare VG-resultate d.m.v. die augerboormetode te verkry, behoort monsters in inkremente van 25mm geneem te word. VG-metings behoort in die mees kritiese dele van 'n paal gedoen te word byv. by TGL en nie hoër nie omdat daar normaalweg beduidende VG-variasie in die longitudinale rigting is. Dis ook belangrik om op meer as een posisie op die omtrek te meet om vir die variasie in die tangensiale rigting voorsiening te maak. Ligte drogingstoestande behoort aan die begin van die drogingsproses by pale met groot spinthoutdieptes, bv. > 15mm, gebruik te word omdat sulke pale meer geneigd tot oppervlaktekrake is. Pale met hoë kernhoutpersentasies moet ook met geskikte drogingskedules, bv. met lae Tdb, gedroog word om interne barste en ineenstorting te verminder. Oor die algemeen behoort Tdb laer as 80oC oorweeg te word om die omvang van defekte by aanvaarbare vlakke te hou. Selfs by Tdb so hoog as 80oC behoort pale langer as 8 dae te droog om die VG tot by aanvaarbare waardes en 'n gradiënt te bring. Omdat slegs drie skedules evalueer is, behoort meer skedules ondersoek word om betroubare gevolgtrekkings oor die effek van skedule op drogingsdefekte te verskaf. Addisioneel behoort meer pale per skedule oorweeg word om statisties betroubare resultate te verkry. Die verwantskap tussen paaldeursnee en drogingsdefekte benodig ook verdere ondersoek. Aangesien 'n beperkte aantal pale gebruik is om die herkoms en drogingskedule met defekte te korreleer, behoort verdere studie op genoeg pale gedoen te word om meer betroubare gevolgtrekkings te kry. Dit is ook noodsaaklik om die moontlike variasie in die korrelasie tussen VPUL en interne defekte op 'n groot aantal pale van spesifieke herkoms en drogingskedules vas te stel.
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Hopegood, Lyn. "Tubule density, moisture content and mechanical properties of donkey hoof horn." Thesis, De Montfort University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.511533.
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Edwards, Joseph Richard. "Equilibrium moisture content measurement for porous building materials at various temperatures." Thesis, This resource online, 1996. http://scholar.lib.vt.edu/theses/available/etd-03042009-041243/.
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Zeywar, Nadim Shukry 1959. "Effect of sensor placement on the relationships of crop water stress index, soil moisture tension and soil moisture content." Thesis, The University of Arizona, 1988. http://hdl.handle.net/10150/191981.
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A field experiment was conducted to investigate the feasibility of making one measurement of soil moisture tension/content or crop water stress index (CWSI), and from it determine when and how much to irrigate. Cotton (Gossvpium hirsutum C.V. DPL-90) was planted in a sandy loam soil prepared with an underground drip irrigation system. Measurements of soil moisture tension, soil moisture content, plant temperature, and wet- and dry-bulb temperatures were made. The results indicate that soil moisture tension above 0.30 m and soil moisture content above 0.50 m in the root zone can be used as good indicators for CWSI or vice versa. Further work is required using different irrigation systems and different crops in larger land areas.
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Dutra, de Melo Lucas. "MOISTURE CONTROL METHODOLOGY FOR GAS PHASE COMPOST BIOFILTERS." UKnowledge, 2011. http://uknowledge.uky.edu/bae_etds/2.
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Gas phase biofilters are used for controlling odors from animal facilities. Some characteristics can affect their performance and moisture content is one very important. A methodology for controlling and measuring moisture content is required to optimize these systems. An experiment was conducted to determine the appropriate placement of a set of soaker hoses 1.2 m in length for water application. It was found that the soaker hose installed in the lower region of the biofilter coupled with appropriate and timely application of water was able to minimize drying of the compost. Thermal conductance proved to be a reliable indicator for measuring the moisture content. Biofilters using the soaker hoses together with the thermal conductance as a media moisture sensor were able to maintain moisture content above 30% w.b. which provided sufficient water for microbial activity and ammonia abatement. A characterization of the ammonia and nitrous oxide concentrations was performed in order to compare the behavior of the gases when water was applied versus no water addition. These analyses revealed that the overall performance was not significantly different between treatments. But a more detailed assessment inside the biofilter media is performed; it is possible to identify different processes taking place.
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Brown, Dawn Gayatri. "Physical characterisation of a commercial magnesium stearate powder." Thesis, University College London (University of London), 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307588.
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Karunakaran, Chithra. "Modelling safe storage time of high (17 and 19%) moisture content wheat." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0007/MQ45068.pdf.
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Lyda, Kelsey R. "An Experimental Study of Moisture Content for a Feed Mill Wet Bin." Youngstown State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1504003187388186.
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Chen, Zhangjing. "Measurement of wood moisture content above fiber saturation point by electrical resistance." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-11102009-020203/.
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Li, Guang. "The effect of moisture content on the tensile strength properties of concrete." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0004782.
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Al-Ismaily, Said Salim. "Nitrogen mineralization of manure-amended soil: Effects of salinity and moisture content." Diss., The University of Arizona, 2004. http://hdl.handle.net/10150/290018.
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Application of manure has been used to increase the nitrogen status of many arid and semi-arid agricultural soils, however, organic nitrogen contained in animal manures must be mineralized prior to utilization by crops. Nitrogen mineralization is, like other biological processes, affected by soil water status. This can be due to the direct influence of soil moisture and/or salt interactions on the nitrogen dynamics. It is critical to understand the interactive effects of salt and water on nitrogen in soils amended with organic fertilizer. Such knowledge may be used for improving and quantifying nitrogen use efficiency. Objectives of this study were (i) to examine the relative and interactive influences of soil osmotic and matric water potentials on nitrogen transformations in manure-amended and non-manured soils, (ii) to determine the extent of nitrogen mineralization over a range of soil water potentials, and (iii) to study the effect of manure addition on nitrogen dynamics in an agricultural desert soil. Gila fine sandy loam soil was treated by addition of varying amounts of distilled water, NaCl, and dairy manure and incubated at depth of 20 cm in 0.025 mm thickness Ziploc® bags. Ammonium nitrogen, nitrate nitrogen, gravimetric soil moisture content, and total soil water potential were measured weekly for 16 weeks. Our study showed a decrease in the amount of inorganic N released from both the non-manured and manure-amended soils at total soil water potentials of approximately -55 bars or less. Maximal amounts of inorganic-N were released at potentials of -23 to -3.5 bars. There was an accumulation in the amounts of NH₄-N released at potentials of -55 bars or less, presumably because of a reduction in net nitrification. The manure caused nitrogen immobilization especially during the early part of our study. Immobilization also occurred in non-manured soil, but this generally lasted only a few weeks. Immobilization was prolonged in soils with lower water potentials. Net N mineralization in the manure-amended soils was higher than in the non-manured soils when soil moisture content was at field capacity.
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Mainey, Alexander J. "The mechanisms of moisture driven backout of nailplate connections. Solutions for outdoor environments and numerical modelling and predictions of moisture driven backout given climatic data." Thesis, Griffith University, 2021. http://hdl.handle.net/10072/404468.
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Nailplated timber trusses, manufactured from timber members connected by nailplates, are widely used in the domestic and international housing market as part of the roofing and flooring systems. The extensive use of these structural elements is driven primarily by their cost efficiency, resulting from an efficient manufacturing process, and their structural efficiency. The use of such trusses however is typically limited to protected (or indoor) environments due to a phenomenon called “nailplate backout”. Nailplate backout is where the steel nailplate, used to connect two timber members together, separates from the parent timber. It is primarily caused by the repeated shrinking and swelling of the timber in response to changing environmental conditions. This moisture driven backout presents a significant hurdle to the expansion of the nailplated timber truss market for external use (and potentially application in the emerging mid-rise timber building market where the internal climatic conditions are relatively unknown). As part as a collaborative project between the industry, Griffith University and Queensland Department of Agriculture and Fisheries (DAF), this thesis aims at investigating solutions to both prevent backout of the nailplates and increase the performance of trussed joints when exposed to large moisture content variations and to develop the understanding of moisture driven nailplate backout through experimental and numerical modelling.
Initially an investigation into redesigning the nailplate tooth to reduce the moisture driven backout was conducted. The proposed tooth redesign considered (i) two mechanical approaches consisting of redesigning the tooth profile and (ii) the application of an adhesive to a redesigned tooth profile. The effectiveness of the new designs was assessed using single nails, representative of a single nailplate tooth, with respect to their ability to resist moisture driven backout and their quasi-static withdrawal resistance after an increasing number of moisture cycles. Results indicated that the mechanical and adhesive approaches could effectively reduce the backout and obtain a higher withdrawal strength than currently used profiles.
The re-designed tooth profiles were then adapted and implemented into a full nailplate to investigate if the results from single tooth would translate to a nailplate joint, particularly after the joints were subjected to severe accelerated moisture cycles. One mechanical-based and one adhesive-based nailplate design were considered and compared to currently commercially available nailplates. The backout of the nailplate was recorded at discrete intervals and the tensile capacity of the joint was also investigated. Findings included a reduction in the rate of backout and a statistically significant increase in tensile capacity in most cases for both proposed designs.
Finally, this thesis proposes an analytical model to predict moisture driven backout as a function of the timber properties, tooth profile and climatic conditions that the joint will be exposed to. The model was validated against experimental data where the backout of a single tooth was pressed into a timber piece and monitored in real time using digital image correlation. The application of the model is then demonstrated by predicting the expected range of nailplate backout in two roof spaces.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Eng & Built Env
Science, Environment, Engineering and Technology
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Ceccato, Pietro. "Estimation of vegetation water content using remote sensing for the assessment of fire risk occurrence and burning efficiency." Thesis, University of Greenwich, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369147.
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Dai, Guangya. "Measuring and monitoring the moisture content of timber and investigation of sorption processes." Thesis, University of Bedfordshire, 1999. http://hdl.handle.net/10547/337409.
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There is little doubt that moisture is a very important factor in relation to material durability. The need for tools to assist in the better understanding and systematic evaluation of moisture movement with the view of incorporating the results within the overall framework of the defect investigation, quality control, and long-term monitoring of moisture, have led to the development of various moisture monitoring and predicting techniques. With the purpose of helping to harmonise the interests in this field, this thesis addresses three major issues in the area of wood moisture. Various studies carried out have been shown that there are substantial discrepancies between specific timber species and published charts for equilibrium moisture content. One of the main objectives of this research was to focus on establishing the equilibrium moisture content for a range of relative humidity and temperature on an individual basis, for twenty commercially important species used in the United Kingdom. The rationale for carrying out the project, the results from the initial trial and the mainstream experiment, the hardware and methodology developed are provided. To meet the requirements of long term accurate and reliable moisture monitoring and to provide comprehensive moisture information, a new type of moisture sensor and related measurement system were developed. The methodology of system design and test procedures are described, emphasising the anti-polarisation method, noise rejection and contact resistance reduction techniques employed. Other aspects of the electrical performance of timber were also investigated. Results from a case study showed that the sensor developed can operate in the critical range of relative humidity with sensitive and accuracy. In the final part of the project, two moisture transport models were developed. Mathematical prediction models in both one dimension and three dimensions are presented for simulating the adsorption and desorption processes in wood. Comparisons are made against long-term experimental data for the one dimensional model. The finite differential method was employed to solve the mathematical expressions developed, resulting in accurate prediction of concentration-driven moisture flows. Investigations were also carried out into the moisture diffusion coefficient and moisture behaviour in the three principal wood directions by using the sensor developed which provided isothermal real-time continuous data.
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Saldanha, Sachin Mervin. "Effect of moisture content on the desorption of carbon tetrachloride from Hanford silt." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Spring2009/s_saldanha_050409.pdf.
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Thesis (M.S. in environmental engineering)--Washington State University, May 2009.Title from PDF title page (viewed on June 19, 2009). "Department of Civil and Environmental Engineering." Includes bibliographical references (p. 58-61).
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Thornburg, Todd Mark 1955. "Electrical resistivity of unsaturated, fractured tuff: influence of moisture content and geologic structure." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/558137.
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Liaghat, Abdolmajid. "Effect of clay type and clay content on moisture content and bulk soil electrical conductivity as measured using time domain reflectometry." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68199.
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Time domain reflectometry (TDR) is becoming a widely used method to determine volumetric soil water content ($ theta$) and bulk soil electrical conductivity (EC$ sb{ rm a}$). It has been found that the $ theta$ and EC$ sb{ rm a}$ values obtained by this method, on certain soils, require calibration. The purpose of this study was to monitor the effects of soil texture (most particularly the clay type and clay content) on $ theta$ and EC$ sb{ rm a}$ estimated by TDR.Water content was measured, gravimetrically and by TDR, on packed columns of nine soil mixtures, composed of three clay types (Hydrite, Bentonite, and Ste. Rosalie clay) and coarse sand at three levels (8, 16, and 30% by weight) of these clay materials. Three replicates of each mixture (a total of 27 columns) were made to statistically establish the effect of the clay type and the clay content on $ theta$ and EC$ sb{ rm a}$ readings by TDR. It was found that the TDR overestimated $ theta$ for the Hydrite and Ste. Rosalie (Natural) materials but accurately predicted for the Bentonite materials, compared to gravimetric determinations.
Bulk soil electrical conductivity was simultaneously measured by two independent techniques, TDR and 4-probe, on the same soils. It was found that the clay types and clay contents have almost equal effects on the EC$ sb{ rm a}$ as measured by TDR and 4-probe techniques. It was found that the estimated EC$ sb{ rm a}$ values obtained by TDR and 4-probe methods for the fine-textured Bentonite materials were lower than those for the Hydrite and Ste. Rosalie materials at equal $ theta$ and EC$ sb{ rm W}$ (electrical conductivity of soil water).
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Jakobsson, Catharina. "Optimization of modified moisture measurement with Karl Fischer to measure moisture content in freeze-dried enzyme beads for improvement of diagnostic kits." Thesis, KTH, Kemiteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-266375.
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Cepheid provides instruments and tests for molecular diagnostic testing of bacterial and viral diseases. Their goal is to deliver a better way to improve patient outcomes by enabling access to molecular diagnostic testing everywhere. These test kits are used in warm and humid countries which may challenge the stability of the kits. The test kits containly ophilized beads, which contain enzymes for the polymerase chain reaction, which usually ages first. The ageing of the beads is effected by the initial water content in them since it defines the quality. Therefore, it is of great importance to have a very precise and exact water measurement method. The degree project covers the optimization of the Standard Operating Procedure used today at Cepheid with the research question: Can optimization of the Karl Fischer method improve the precision when measuring the initial moisture content of freeze-dried enzyme beads? The method for measuring the water content was the Karl Fischer titration method and the instrument used was the Mettler Toledo C30S Compact Karl Fischer-coulometer. The different optimized parameters were the sample preparation, extraction process and how the measurement was proceeded. It can be concluded that optimized method provides significantly different results compared with the old method and therefore the new method is better.Cepheid tillverkar instrument och test för molekylär diagnostisk testning av bakteriella och virala sjukdomar. Målet är att leverera en lösning som leder till en förbättring för patienterna genom att möjliggöra tillgång till molekylär diagnostisk var än den behöver utföras i världen, under stora variationer i mätmiljön. Dessa testkit används i varma och fuktigalä nder vilket kan utmana stabiliteten hos produkten. Testen innehåller lyofiliserade kulor och det är dessa som vanligtvis åldras först. Kulornas hållbarhet påverkas av den ursprungliga vattenhalten, vilket definierar kvalit´en. Därför är det mycket viktigt att ha en mycket exakt metod att mäta fuktinnehållet i kulorna. Examensarbetet omfattar optimering av den standardoperativa proceduren som används idag på Cepheid och fr°ageställningen är: Kan optimering av Karl Fischer-metoden förbättra precisionen vid mätning av det ursprungliga fuktinnehållet i frystorkade enzymkulor?Den metod som används vid mätningen av vattenhalten är Karl Fischer-titreringsmetoden och instrumentet som användes var Mettler Toledo C30S Compact Karl Fischer-coulometer. De olika optimerade parametrarna var: förberedelsen av proven, extraktionsprocessen och själva utförandet av mätningen.Den slutsats som kan dras efter optimeringen är att den nya metoden ger ett mer exakt och bättre resultat än den gamla.
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Shevelan, John. "Investigating the effects of heterogeneities on infiltration into unsaturated compacted soils." Thesis, University of Sheffield, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369917.
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Alhabeeb, Abdulrahman S. I. "Effects of irrigation and plant density on growth and yield of faba bean (Vicia Faba L.)." Thesis, University of Reading, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267430.
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Zein, Abdel Karim Mohammad. "Swelling characteristics and microfabric of compacted black cotton soil." Thesis, University of Strathclyde, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.332595.
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George, Brendan Hugh. "Comparison of techniques for measuring the water content of soil and other porous media." University of Sydney, 1999. http://hdl.handle.net/2123/491.
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The measurement of water in soil on a potential, gravimetric or volumetric basis is considered, with studies concentrating on the measurement of water by dielectric and neutron moderation methods. The ability of the time-domain reflectometry technique to measure water content simultaneously at different spatial locations is an important advantage of the technique. The reported apparent dielectric by the TRASE� time-domain reflectometer and Pyelab time-domain reflectometry systems is sensitive to change in extension cable length. In some soil, e.g. a commercial sand, the response to increasing extension length of extension cable is linear. For other soil a linear response occurs for certain lengths of cable at different moisture contents. A single model accounting for clay content, extension cable length, time-domain reflectometry system, probe type and inherent moisture conditions explained 62.2 % of variation from the control (0 m extension) cable. The extension cable causes a decrease in the returning electromagnetic-wave energy; leading to a decline in the slope used in automatic end-point determination. Calibration for each probe installation when the soil is saturated, and at small water contents is recommended. The ability of time-domain reflectometry, frequency-domain and neutron moderation techniques in measuring soil water content in a Brown Chromosol is examined. An in situ calibration, across a limited range of water contents, for the neutron moderation method is more sensitive to changing soil water content than the factory supplied 'universal' calibration. Comparison of the EnviroSCAN� frequency-domain system and the NMM count ratio indicates the frequency-domain technique is more sensitive to change in soil water conditions. The EnviroSCAN� system is well suited to continuous profile-based measurement of soil water content. Results with the time-domain reflectometry technique were disappointing, indicating the limited applicability of time-domain reflectometry in profile based soil water content measurement in heavy-textured soil, or soil with a large electrical conductivity. The method of auguring to a known depth and placement of the time-domain reflectometry probe into undisturbed soil is not recommended. A time-domain reflectometry system is adapted for in situ measurement of water in an iron ore stockpile. The laboratory calibration for water content of the processed iron ore compares favourably to a field calibration. In the field study, the 28 m extension cable used to connect the probes to the time-domain reflectometry affected the end-point determination of the time-domain reflectometry system. To account for this, 0.197 should be subtracted from the reported apparent dielectric before calculation of volumetric moisture content.
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Vu, Thanh Hien Thi. "Preparation, characterization, and evaluation of sorghum flour with increased resistant starch content." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/32171.
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Master of ScienceDepartment of Grain Science and Industry
Yong-Cheng Shi
Sorghum flour is a gluten-free ingredient and can be used to prepare foods for celiac patients. In addition, sorghum flour is a good source of fiber in the form of resistant starch. The objectives of this research were to develop an effective process to increase resistant starch content of sorghum flour and investigate the effects of sorghum protein matrix on starch digestibility. Samples of white sorghum flour (28.9% amylose content) with different moisture contents (0%, 12.5%, 20%, and 30%) were treated at different temperatures (100, 120, and 140 [degrees]C) for different times (1, 2, and 4 h). Samples after heat treatments were tested for starch digestibility, protein digestibility, differential scanning calorimetry (DSC), size-exclusion chromatography (SEC), and X-ray diffraction. The sample treated with 20% moisture at 100[degrees]C for 4 h had high resistant starch (RS) content (22.1% compared with 5.6% of the native sample) and low protein digestibility (8.4% compared with 68.3% of the native sample). The same heat-moisture treatment on isolated sorghum starch showed no significant change in RS content. DSC showed a very low degree of gelatinization for samples treated at moisture contents 20% and below. X-ray diffraction also suggested minimal change in starch crystallinity after heat treatment at low moisture contents (20% and below). Sorghum protein solubility after heat treatment was reduced, suggesting that protein structure was altered during the heat treatments. In conclusion, heat-moisture treatments were successful in increasing resistant starch content of sorghum flour by altering sorghum protein without gelatinizing the starch to retain starch functionality in food product applications. Sorghum flour with increased resistant starch content after heat treatment was evaluated and compared with normal sorghum flour for starch digestibility using the Integrated Total Dietary Fiber method, and for food applications in tortillas.
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Maguire, Seamus. "Bale weighing, crop moisture content measurement and yield mapping systems for large rectangular balers." Thesis, Cranfield University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.443752.
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Miller, Wieberg Danielle A. "Establishing the perimortem interval correlation between bone moisture content and blunt force trauma characters /." Diss., Columbia, Mo. : University of Missouri-Columbia, 2006. http://hdl.handle.net/10355/5907.
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Thesis (M.A.)--University of Missouri-Columbia, 2006.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on September 14, 207) Includes bibliographical references.
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Tilert, Dan. "Development of techniques for measurements of shock wave response and moisture content in granite." Licentiate thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-573.
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Gaillemard, Christelle. "Modelling the Moisture Content of Multi-Ply Paperboard in the Paper Machine Drying Section." Licentiate thesis, Stockholm : Department of Mathematics, Royal Institute of Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3903.
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