Dissertations / Theses: 'Flow aid'

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Shabbir, Muhammad Humas. "Streamlining information and part flow by re-designing process flow to aid root cause analysis." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/113727.

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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2017.
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (page 63).
Waters Corporation is a world leading analytical instrument manufacturing company, with an overarching goal of achieving and maintaining high product robustness. Analysis of the challenge identifies the problem of lack of root cause analysis. This is further attributed to the inefficient process flow of information and parts: there is a lack of tracking mechanism for parts which is induced from lack of ownership and value at each stage of the root cause analysis phase. A new process flow is designed around the current process to address gaps and inefficiencies. This process flow redesign is done for both information flow for hot parts list and the movement of parts; this will streamline the overall root cause process and secondarily help save cost and eliminate redundancies. A layout improvement solution is developed, and a plan for implementation recommended. The new process flow is designed to increase visual control of the process and to effectively move the material. Each phase of the project has been reviewed and discussed to encourage stakeholder involvement in order to develop a continuous improvement culture.
by Muhammad Humas Shabbir.
M. Eng.

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Houston, Jonas H. "Developing Dendrifrom Facades Using Flow Nets as a Design Aid." DigitalCommons@CalPoly, 2011. https://digitalcommons.calpoly.edu/theses/670.

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This thesis highlights a method of arriving at form that minimizes the need for high end technology and complex mathematical models, yet has structural principles of load flow at the highlighted methods core. Similar to how graphical statics assisted earlier architects and engineers to arrive at form by relating form and forces, this thesis suggests a method of form finding that relates the flow of stresses within solid masses to possible load-bearing façades. Looking to nature, where an abundance of efficient structural solutions can be found, this thesis focuses on a tree-like structural form called the dendriform. In doing so, this thesis explores the idea that through an understanding of typical load flow patterns and the removal of minimally stressed material of the solid body, dendriforms can be revealed that qualitatively exemplify load flow yet maintain an architectural aesthetic.

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Åkesson, Anna. "Hydraulic- hydromorphologic analysis as an aid for improving peak flow predictions." Licentiate thesis, KTH, Vattendragsteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-25425.

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Conventional hydrological compartmental models have been shown to exhibit a high degree of uncertainty for predictions of peak flows, such as the design floods for design of hydropower infrastructure. One reason for these uncertainties is that conventional models are parameterised using statistical methods based on how catchments have responded in the past. Because the rare occurrence of peak flows, these are underrepresented during the periods used for calibration. This implies that the model has to be extrapolated beyond the discharge intervals where it has been calibrated. In this thesis, hydromechanical approaches are used to investigate the properties of stream networks, reflecting mechanisms including stage dependency, damming effects, interactions between tributaries (network effects) and the topography of the stream network. Further, it is investigated how these properties can be incorporated into the streamflow response functions of compartmental hydrological models. The response of the stream network was shown to vary strongly with stage in a non-linear manner, an effect that is commonly not accounted for in model formulation. The non-linearity is particularly linked to the flooding of stream channels and interactions with the flow on flood-plains. An evaluation of the significance of using physically based response functions on discharge predictions in a few sub-catchments in Southern Sweden show improvements (compared to a conventional model) in discharge predictions – particularly when modelling peak discharges. An additional benefit of replacing statistical parameterisation methods with physical parameterisation methods is the possibility of hydrological modelling during non-stationary conditions, such as the ongoing climate change.
QC 20101022

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Miller, Adin T. "Walking Assistant - A Mobile Aid for the Visually-Impaired." DigitalCommons@CalPoly, 2014. https://digitalcommons.calpoly.edu/theses/1262.

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The most common navigation aid visually-impaired people employ is a white cane, but, recently, technology has given rise to a varied set of sophisticated navigation aids. While these new aids can provide more assistance to a visually-impaired person than a white cane, they tend to be expensive due to a small market segment, which in turn can reduce their accessibility. In an effort to produce a technologically-advanced yet accessible navigation aid, an Android application is proposed that detects and notifies users about obstacles within their path through the use of a smartphone's camera. While the smartphone is mounted on a harness worn by the user, the Walking Assistant application operates by capturing images as the user walks, finding features of objects within each frame, and determining how the features have moved from image to image. If it is discovered that an object is moving towards the user, the Walking Assistant will activate the smartphone's vibration mode to alert the user to the object's presence. Additionally, the user can control the Walking Assistant through the use of either touch or voice commands. By conducting real-world tests, it was determined that the Walking Assistant can correctly identify obstacles 42.1% of the time, while generating false positive obstacle identifications only 15.0% of the time. The accuracy of the Walking Assistant can be further improved by implementing additional features, such as a fuzzy-decision-based thresholding system or image stabilization.

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Buys, Angela. "Development of a flow cytometric bead immunoassay as an aid to potency evaluation of enterotoxaemia vaccines." Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/30924.

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Enterotoxaemia is an economically important disease of sheep, goats and calves. The disease affects mainly young animals aged between four to six months. Enterotoxaemia is caused by systemic effects of the epsilon toxin produced by the anaerobic bacterium Clostridium perfringens Type D. Due to almost certain death of affected animals, there is no form of treatment. The only practical means of controlling the occurrence of enterotoxaemia is to immunize animals through vaccination. The vaccine is prepared by toxoiding the bacterial culture filtrate, and contains a range of proteins in addition to the epsilon toxin. Batches of the vaccine are thus required to be tested for safety, efficacy and potency. The potency of the vaccines is currently tested with the in vivo mouse neutralisation test (MNT). However, due to ethical, economic and technical reasons, alternative in vitro assays are needed. In this study, an indirect cytometric bead immunoassay (I-CBA) was developed for use in vaccine potency testing and the results were compared with those obtained using an indirect ELISA (I-ELISA) and the MNT. To investigate, three groups of eight guinea pigs were immunized with one of three different production batches of the enterotoxaemia vaccine. Guinea pig sera were collected prior to vaccination and at five weeks post-vaccination, and the sera of four guinea pigs per group were pooled to give six test sera. The levels of anti-epsilon toxin antibodies in the respective test sera were subsequently determined using MNT, I-ELISA and I-CBA. The I-CBA assay developed during the course of this study is based on coating of functional beads with purified epsilon toxin that serves to capture anti-epsilon toxin antibodies from the test sera. Following incubation with fluorescein isothiocyanate (FITC)-labelled anti-guinea pig IgG, the samples were analyzed by flow cytometry and the anti-epsilon toxin antibody concentrations were extrapolated from a standard curve using linear curve fitting. Although the intra- and inter-assay variability was satisfactory, epsilon antitoxin levels of the guinea pig test sera determined by both the ICBA and I-ELISA tests were higher than that of the MNT assay which is accepted as the current “gold standard”. Moreover, in contrast to the MNT, all of the serum samples were identified as having antitoxin levels above the required minimum (i.e. not less than 5 U/ml). These results indicate that the respective in vitro tests in their current formats are not yet suitable alternatives to the in vivo MNT. The growing demand for a more humane, cost-effective and efficient method for testing the potency of enterotoxaemia vaccines, however, provides a strong impetus for further optimization and standardization of the I-CBA assay described in this study.
Dissertation (MSc)--University of Pretoria, 2012.
Microbiology and Plant Pathology
MSc
Unrestricted

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Gezimati, Robinson. "Good governance as key to the flow of foreign development aid: the sub-Saharan Africa perspective." Thesis, University Of Cape Town, 2018. http://hdl.handle.net/11427/29947.

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The aim of this study was to evaluate the importance of good governance to the flow of foreign development aid. The researcher used the sub-Saharan Africa region to accomplish the aim of his study. The study examined the extent to which foreign development aid has been targeted at countries with sound governance systems, that is, strong institutions and policies. This study therefore determined whether the flow of foreign development aid in sub-Saharan African developing countries has changed since the endorsement of the “Monterrey Consensus” by targeting those countries with sound economic institutions and policy environments. Empirical and theoretical literature was reviewed on foreign development aid as well as governance systems especially the Ibrahim Index of African Governance (IIAG), which was discussed and used in this study as the governance indicator system. The study’s results and findings were deduced from secondary data which addressed the governance indicators in sub-Saharan Africa for 2010 to 2015, gathered from the IIAG assessment reports of 12 selected sub-Saharan African countries as well as the amount of foreign development aid received by each of the countries during the same period gathered from OECD and World Bank statistics. Additionally, inferential analysis was undertaken using the Spearman’s correlation test as well as a multiple linear regression analysis to establish the relationships and/or impact of the governance indicators on the flow of foreign development aid to sub-Saharan Africa. The study concluded that the combined effect of all the governance indicators have a statistical significant effect on the flow of foreign development aid to developing countries in sub-Saharan Africa. Individually, Participation and Human Rights indicators as well as Sustainable Economic Opportunities indicators have a positive effect or impact on the flow of foreign development aid in sub-Saharan African countries, with Sustainable Economic Opportunities indicators having the highest impact. However, Safety and Rule of Law indicators were discovered to have a negative effect on the flow of foreign development aid in sub-Saharan Africa whilst Human Development indicators were discovered not to have any effect or impact. On the other hand, the study also noted that in further determining allocations funding agencies may consider a country’s Safety and Rule of Law indicators as well as Human Development indicators whilst Participation and Human Rights indicators and Sustainable Economic Opportunity indicators were seen not have any significant effect on determination of funding allocations.

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Svedberg, Anna. "Improvement of the retention-fromation relationship using three-component retention aid systems." Doctoral thesis, KTH, Fiberteknologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-96259.

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Weseman, Brian D. "The Effects of Retention Aid Dosage and Mechanical Energy Dissipation on Fiber Flocculation in a Flow Channel." Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/7960.

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Formation plays an important role in the end-use properties of paper products, but before formation can be optimized to achieve superior properties, an understanding about the causes of formation must be developed. Formation is caused by variations in the basis weight of paper that are results of fiber floc formation before and during the forming of the sheet. This project is a first step in a larger research program aimed at studying formation. By observing the effects that mechanical energy dissipation (in the form of turbulence) and retention chemical dosage have on floc formation, we may develop a better understanding of how to control formation. In this study, a rectangular cross-section flow channel was constructed to aid in the acquisition of digital images of a flowing fiber suspension. The furnish consisted of a 55:45 spruce:pine bleached market pulp mix from a Western Canadian mill. Turbulence was varied by changing the flow rate; Reynolds numbers achieved range from 20,000 to 40,000. The retention aid used was a cationic polyacrylamide with a medium charge density. Dosage of the retention aid was varied from 0 to 2 pounds per ton OD fiber. Digital images of the flowing fiber suspension were acquired with a professional digital SLR camera with a forensics-quality lens. Three separate image analysis techniques were used to measure the flocculation state of the fiber suspension: morphological image operations, formation number analysis, and fast Fourier transform analysis. Morphological image analysis was capable of measuring floc size increases seen in the acquired floc images. It was shown how floc diameter could increase simultaneously with decreasing total floc area and total floc number. A regression model relating retention aid dosage and energy dissipation was constructed in an effort to predict flocculation. The regression model was used to predict F2 (formation number squared) results from the study. The interaction effect RE was shown to have a differing effect across the retention aid dosage levels. As a result, this model and technique may prove to be a beneficial tool in optimizing retention aid applications.

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Eliasson, Åse. "Groundwater impact assessment and protection." Licentiate thesis, KTH, Civil and Environmental Engineering, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-1234.

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In the recent decades, therehave been frequent conflicts between groundwater waterresources and environmentally hazardous activities. Newmethodologies for aiding decision-making in groundwater impactassessment and protection areneeded and in which issues ofincreased awareness, better understanding of the groundwaterresources processes, and validation of predictive mathematicalmodels are addressed.

A framework fordecisionaid, based on predictive simulations that a)predicts the environmental impacts b) provides the totaleconomical value c) visualises the impacts and the groundwaterproperties and d) describes the uncertainties in the results isproposed herein. The framework can be applied in environmentalimpact assessments, strategic environmental assessments andprotection and management of water resources. The results ofthe model are used as feedback for determining new scenarios,depending on the required uncertainties, and if the plannedactivity is sustainable, and/or fulfils the legislative andpolicy measures. This framework is applied to a particular casestudy, Nybroåsen, in the south-eastern part of Sweden,where the highway E22 is constructed through the importantglaciofluvial esker aquifer, passing the protection zone of thewater supply for the Kalmar municipality.

The impacts from the new highwayand the existing road have been predicted by two-dimensionalphysically based time-variant flow and solute groundwatermodelling. The results, breakthrough curves of contaminantconcentration in wells and maps of concentration distributions,as well as travel times, flow paths, and capture zones forwells determined by particle tracking have been presented.

The constructed model of theNybroåsen study area was calibrated by comparing observedand simulated groundwater levels for 15 observation wells forten years of measurements. The model has been evaluated bothgraphically and numerically and the calibration target wasfulfilled for 13 of the 15 observation wells. The model workincludes investigations of the catchment information, a waterbalance study, simulation of the groundwater recharge,consideration of the unsaturated zone by a numerical columnsimulation, and sensitivity analysis.

From the sensitivity analysis ofthe flow and transport parameters, it has been shown that theuncertainties are mainly due to the hydraulic conductivity.Comparison of the derived conductivity from the steady-stateautomatic calibration and the time-variant calibration showedthat there are major differences in the derived parameters,which illustrates the importance of a time dependentcalibration over both wet and dry periods and in more than onepoint in the area of interest of the model predictions.

In addition, a multi-criteriadecision analysis has been carried out for four roadalternatives (including the new highway E22) and the existingroad in the case study concerned. The multi-criteria decisionaid is applied as an illustration of how it can be used in thestudy area to identify a) interest groups of actors and theirconcerns b) ranking of alternative road scenarios according toactorspreferences and c) coalition groups of actorsi.e.groups that have similar views with regard to theroad alternatives.

Keywords:Physically-based groundwater modelling,contamination, flow and solute transport, glaciofluvialdeposits, Nybroåsen, Sweden, and multi-criteriadecision-aid.

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Miclo, Romain. "Challenging the "Demand Driven MRP" Promises : a Discrete Event Simulation Approach." Thesis, Ecole nationale des Mines d'Albi-Carmaux, 2016. http://www.theses.fr/2016EMAC0016/document.

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Les principaux enjeux des supply chain d’aujourd’hui concernent l’adaptation à des environnements instables. Demand Driven Material Requirements Planning (DDMRP) est une méthode récente et prometteuse de gestion des flux qui a été conçue pour faire face aux problématiques actuelles. Le travail de recherche réalisé détaille et positionne DDMRP par rapport aux autres méthodes connues de pilotage de flux. Le but de ce travail est de challenger les principales promesses de DDMRP. Pour cela, un plan d’expériences a été réalisé sur un cas d’étude pour évaluer le comportement de MRP II, Kanban et DDMRP face à différentes sources de variabilité. Le dimensionnement des buffers DDMRP est un sujet majeur pour la méthode. Il a été traité sur un cas d’étude avec un travail d’optimisation. Toutes les contributions ont été expérimentées avec l’implémentation de DDMRP sur un cas réel. La thèse permet ainsi de valider certains atouts de DDMRP, tels que l’adaptation du système à différentes formes de variabilités, mais elle permet également de souligner des perspectives majeures de recherche sur ce sujet
The main Supply Chain current issues concern the adaptation to unstable environments. Demand Driven Material Requirements Planning (DDMRP) is a recent and promising material management method that is designed to tackle these current issues. The research work details and classifies DDMRP compared to the other material management methods known. The goal of this work is to challenge the main DDMRP promises. This is why a design of experiments was realised on a case study in order to assess MRP II, Kanban and DDMRP behaviours with different variability sources. The DDMRP buffer sizing is a major issue. It was dealt with an optimisation work on a case study. All the contributions were experimented with a DDMRP implementation on a real case. The research work enables several DDMRP advantages to be validated, such as the system adjustment to different variability sources, however this work also allows research perspectives to be underlined

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Al-Shaghdari, Mohammed A. "The evaluation of time-dependent flow in swirl burners." Thesis, University of South Wales, 1997. https://pure.southwales.ac.uk/en/studentthesis/the-evaluation-of-timedependent-flow-in-swirl-burners(e2caff50-bfda-4bc9-85f4-e91182d53bd7).html.

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Swirl burners are widely used in industry. Recent environmental concerns, particularly on emissions from combustion processes, have introduced the requirement to modify these processes to reduce emissions whilst at the same time maintaining combustion efficiency. This thesis presents details of experimental and computational studies into the flowfield structures of swirl burners. Previous investigators have concentrated on the time-average flows, but it has become apparent that these are insufficient to enable pollutant emissions to be accurately predicted. Knowledge of the time-temperature and species history is needed to obtain better predictions. Pivotal to this is a detailed determination of the time-dependent structure of the flow. In this study, series of experiments were carried out at different inlet configurations and conditions. The flowrate and swirl number were varied as well as the injection mode, inlet length and exit geometry. The burner flow was characterised by measuring axial, tangential and radial velocities using a Laser Doppler Anemometer. A Computational Fluid Dynamics modelling package, FLUENT was used to produce two and three-dimensional computational models to predict the flowfield structures of the burners in isothermal and combustion cases. Four turbulence models were evaluated in the prediction: the k-e Model, the Algebraic Stress Model (ASM), the Reynolds Stress Model (RSM) and the Re-normalisation Group Model (RNG). Constant velocity scaling of the 100 and 500 kW burner was examined in both experimental and computational studies. The experimental results show that the flowfield structures in both burners are nonaxisymmetric and develop three-dimensional time-dependent coherent structures in the flow. The experimental results have been compared with the computational model predictions. The comparisons reveal very good agreement between the time average measurement and the predictive values, especially downstream of the burner exit. This work was extended to investigate the following novel phenomena: a). The computational prediction of the flowfield structure was extended to include different inlet boundary conditions with both the RSM and the RNG turbulence models. The model was also extended to investigate the time-dependent flows. b). The influence of varying the inlet and exit geometries and conditions on the flow patterns and the reverse flow zone was examined in detail. A 500 kW swirl burner with scroll inlet was designed and characterized with time-dependent flows to simulate the Precessing Vortex Core. This investigation showed very good agreement with experimental velocity data with less constrained boundary conditions that had previously obtained. The time-dependent simulation was limited by the computer speed and processing capability but identified that such analysis is possible when computer power allows and has the potential to model the flow in greater detail yielding more accurate data on pollution emissions.

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Johnson, Christopher Gurney. "Granular shocks, particle size segregation and levee formation in avalanches and debris flows." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/granular-shocks-particle-size-segregation-and-levee-formation-in-avalanches-and-debris-flows(a90bcaa3-a056-4691-bc8d-de7b484e2590).html.

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Debris flows, avalanches and other geophysical mass flows pose a significant hazard to settlements in or near mountainous regions. Understanding the physical processes that govern these flows is an essential part of hazard assessment and mitigation strategies. This thesis addresses two aspects of geophysical mass flows: flow self-channelisation due to the formation of lateral levees, and granular shocks, which occur when a rapidly-moving debris flow or avalanche collides with an obstacle. We present the results of large-scale debris flow experiments in which the flow is channelised by coarse-particle levees that form at the flow margins. The flow surface velocities are measured with high speed overhead photography, and the deposits both sampled to obtain the grain size distribution and excavated to recover the deposited locations of tracer pebbles that were introduced in to the flow. We propose a model, supported by evidence from the large-scale experiments, that describes in detail the size segregation and kinematic transport processes responsible for the deposition of lateral levees. The second problem addressed in the thesis concerns granular shocks, or jumps, which are rapid changes in the depth and velocity of granular avalanches. We investigate these through experiments in which a falling jet of granular material impacts on an inclined plane, generating a steady granular jump, which is either teardrop-shaped or 'blunted'. Numerical solutions of a depth-averaged flow model agree quantitatively with many of the observed flow features. We use this model show that the transition between the teardrop-shaped and blunted jump regimes corresponds to a transition between two shock reflection structures, known as a regular and a Mach shock reflection. On planes inclined at a shallow angle, we demonstrate a wide variety of unsteady and channelised flows, which occur due to the complex interaction between flowing and stationary regions of granular material.

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Weston, Neil Philip. "A heat flow and vent sizing calorimeter for a complete chemical reaction hazards assessment." Thesis, London South Bank University, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.388167.

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Li, Jie Sheng. "The political economy of foreign aid flows." Thesis, University of Birmingham, 2016. http://etheses.bham.ac.uk//id/eprint/6735/.

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This thesis examines the rise in bilateral aid disbursements over multilateral aid between 2000 and 2010. It would be simply stated that such a trend would be due donor nations focusing on strategic self-interests. I argue, using a combination of principal-agent theory, foreign policy analysis and the effect of institutions, that new political actors in donor nations found a window of opportunity to alter the level foreign disbursements and in several cases, increase the overall level of foreign aid. Bilateral aid eventually rose due to both the worldviews of these new decision makers as well as how their policies were influenced and shaped by local institutions. In this thesis, I focus on the US, the UK and Japan as donor nations and the World Bank’s International Development Association. In the US case, political and cultural institutions along with the worldviews Bush Administration officials shifted US bilateral aid upwards. In the UK, local institutions along with the perspectives of New Labour officials result in higher British bilateral aid disbursements. Japan’s political actors initially focused on the country’s economy but later actors, with their worldviews and shaped by historical norms, increased Japan’s bilateral aid vis-à-vis its contributions to IOs.

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Pečeňa, Lukáš. "Projekt výstavba pečovatelského domu." Master's thesis, Vysoká škola ekonomická v Praze, 2012. http://www.nusl.cz/ntk/nusl-194519.

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The diploma thesis aims to present the method of the project financing on an example of Nursing Home Project. The thesis is focused on examination whether it is possible to finance the private project regarding services of general economic interest just from operational revenues and allowed state aid. The thesis describes regulations of social care system in the Czech Republic and European regulation and directives regarding the state aid. The last chapter is designed as a feasibility study of the whole project. The feasibility study contains model of future project's cash flows. The horizontal and vertical analyses of financial statements of non-profit organization are also part of the thesis.

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Heinemeier and Nicholas Pierce. "Flow speed measurement using two-point collective light scattering." Thesis, Risoe National Laboratory, 1998. http://www.risoe.dk/rispubl/ofd/riso-r-1064.htm.

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Khaire, Swapnil S. "Influence of test section entrance conditions on straight flat oval apparent relative roughness a thesis presented to the faculty of the Graduate School, Tennessee Technological University /." Click to access online, 2009. http://proquest.umi.com/pqdweb?index=0&did=2000385011&SrchMode=1&sid=1&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1277822700&clientId=28564.

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Besarla, Dhaman Kumar. "Modeling and optimization of air flow in a cabin air filtration test duct a thesis presented to the faculty of the Graduate School, Tennessee Technological University /." Click to access online, 2008. http://proquest.umi.com/pqdweb?index=0&did=1679682361&SrchMode=1&sid=2&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1254155722&clientId=28564.

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Rossi, D. "Adipic acid sonocrystallization in continuous flow microchannels." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1557884/.

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Crystallization is widely employed in the manufacture of pharmaceuticals during the intermediate and final stages of purification and separation. The process defines drug chemical purity and physical properties: crystal morphology, size distribution, habit and degree of perfection. Particulate pharmaceuticals are typically manufactured in conventional batch stirred tank crystallizers that are still inadequate with regard to process controllability and reproducibility of the final crystalline product. Variations in crystal characteristics are responsible for a wide range of pharmaceutical formulation problems, related for instance to bioavailability and the chemical and physical stability of drugs in their final dosage forms. This thesis explores the design of a novel crystallization approach which combines in an integrated unit continuous flow, microreactor technology, and ultrasound engineering. By exploiting the various benefits deriving from each technology, the thesis focuses on the experimental characterization of two different nucleation systems: a droplet-based system and a single-phase system. In the former, channel fouling is avoided using a carrier fluid to segment the crystallizing solution in droplets, thus avoiding the contact with the walls. In the latter channel blockage is prevented using larger channel geometries and employing higher flow rates. The flexibility of the developed setup also allows performing stochastic nucleation studies to estimate the nucleation kinetics under silent and sonicated conditions. The experiments reveal that very high nucleation rates, small crystal sizes, narrow size distributions and high crystal yields can be obtained with both setups when the crystallizing solution is exposed to high pressure field as compared to silent condition. It is concluded that transient cavitation of bubbles and its consequences are a significant mechanism for enhancing nucleation of crystals among several proposed in the literature. A preliminary study towards the development and design of a growth stage is finally performed. Flow pulsation is identified as a potential method to enhance radial mixing and narrow residence time distribution therefore achieving optimal conditions for uniform crystal growth. The results suggest that increasing values of Strouhal number as well as amplitude ratio improve axial dispersion. Helically coiled tubes are identified as potential structures to further improve fluid dynamic dispersion.

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Zhou, Jing. "Flow Patterns in Vertical Air/Water Flow With and Without Surfactant." University of Dayton / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1375455656.

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Ricardo, Duarte Jorge Portela. "Oil, foreign aid and FDI flows: The missing link?" Master's thesis, NSBE - UNL, 2013. http://hdl.handle.net/10362/9770.

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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics
This paper studies the possible strategic use of foreign aid to get preferential access to oil. Furthermore, it also addresses the role of oil as a determinant factor for the allocation of Foreign Direct Investment (FDI). Using a panel data set of 48 oil producing countries for a period of 30 years, ranging from 1980 to 2010, it was found that, not only is oil a key factor for the determination of foreign aid and FDI, but also that there is a clear distinction between the importance conceived by donor and/or investing countries in their current and future level of oil dependence.

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Schudel, Carl Jan Willem. "Corruption and International Capital Flows to Developing Countries : Bilateral Aid, Multilateral Aid, and Foreign Direct Investment." Thesis, University of Essex, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.517489.

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Kadja, M. "Computation of recirculating flow in complex domains with algebraic Reynolds stress closure and body fitted meshes." Thesis, University of Manchester, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.384419.

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Balasubramanian, Vivek. "Effectiveness of the "common" method in balancing exhaust ventilation systems." Morgantown, W. Va. : [West Virginia University Libraries], 2005. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4354.

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Thesis (M.S.)--West Virginia University, 2005.
Title from document title page. Document formatted into pages; contains vii, 59 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 48-49).

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Tsui, Ka-cheung. "Neighborhood ventilation of a building cluster by combined forces." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B42182128.

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Ahn, Seungki. "An experimental study of flow over a 6 to 1 prolate spheroid at incidence." Diss., This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-06062008-165846/.

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Talbot, Michael T. "Pressure and velocity distribution for air flow through fruits packed in shipping containers using porous media flow analysis." Gainesville, FL, 1987. http://www.archive.org/details/pressurevelocity00talb.

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Robinson, Robert James. "An expert system to aid ultrasonic flaw modelling results interpretation." Thesis, University of Strathclyde, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428856.

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Guo, Haipeng, and 郭海朋. "Groundwater movement and subsurface air flow induced by land reclamation and tidal fluctuation in coastal aquifers." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40987735.

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Guo, Haipeng. "Groundwater movement and subsurface air flow induced by land reclamation and tidal fluctuation in coastal aquifers." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B40987735.

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31

Chen, Lejun. "Flow patterns in upward two-phase flow in small diameter tubes." Thesis, Brunel University, 2006. http://bura.brunel.ac.uk/handle/2438/5104.

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Two-phase flow in small tubes and channels is becoming a common phenomenon in industrial processes. However, the study of two-phase flow regimes in small tubes is still at its infancy. The previous studies are reviewed and discussed in the literature section. The problems and inconsistencies encountered in the earlier studies are presented and discussed. The experimental facility is introduced in the chapters that follow. They include a section on the design of the experimental system and the test sections, the selection of the experimental parameters and the introduction of the purposely-developed programs to control the experiments and collect and process the data. The methodology of the calibration and the uncertainty analysis, the problems encountered and their solutions and the single-phase validation experiments are also described. In this project we studied the effect of tube diameter and fluid flow parameters on flow patterns in small tubes using R134a as the working fluid. The tested tube diameters were 1.10, 2.01, 2.88 and 4.26 mm; the fluid pressures were 6, 10 and 14 bar; the liquid and gas superficial velocities covered a range of 0.04-5.0 m/s and 0.01-10.0 m/s respectively. The observed flow patterns included bubbly, dispersed bubble, confined bubble, slug, chum, annular and mist flow. Twelve integrated flow maps are sketched in this report. The obtained results were compared with earlier experiments by other workers and with existing models, with obvious differences in the prediction of the transition boundaries. A set of new models and correlations were developed, based on the new data for boiling R134a presented in this thesis, to predict the effect of tube diameter and fluid properties on the transition boundaries. Some also agreed with the limited data available from earlier studies for adiabatic air-water flow in small to normal size tubes.

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Phillips, Andrew. "Two phase flow in rapidly rotating porous media." Thesis, University of Nottingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289324.

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Jangam, Ranjit. "Relationship between damper resistance and damper insertion depth." Morgantown, W. Va. : [West Virginia University Libraries], 2006. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=4509.

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Thesis (M.S.)--West Virginia University, 2006.
Title from document title page. Document formatted into pages; contains xi, 97 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 62-63).

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Judy, Christopher Daniel Shon Paul. "Evaluating the effects of elbows and duct size on the accuracy of hand-held pitot traverse flow measurements." Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5479.

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Thesis (M.S.)--West Virginia University, 2007.
Title from document title page. Document formatted into pages; contains v, 44 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 39-40).

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35

Jalali, Amirjalal. "Quiescent and flow-induced crystallization of poly(lactic acid)." Thèse, Université de Sherbrooke, 2017. http://hdl.handle.net/11143/9892.

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Le poly(acide lactique), PLA, est un polymère biocompatible et biodégradable, qui peut être produit à partir de ressources renouvelables. En conséquence, il a soulevé une attention toute particulière en tant que remplacement éventuel des polymères à base de pétrole. C’est un polyester aliphatique ayant des propriétés telles que module élevé, haute résistance, biocompatibilité et est donc un matériau prometteur pour diverses applications telles que les implants, l’encapsulation de médicaments et l'emballage. A cause de sa faible température de transition vitreuse, le PLA a une faible résistance thermique et les applications sont donc limitées à celles qui ne sont pas associées à des températures élevées. En outre, ce polymère souffre d'un faible degré de cristallinité. L'augmentation du taux de cristallinité dans de nombreuses techniques de mise en forme, telles que le moulage par injection, est nécessaire. Il y a plusieurs façons d'augmenter le niveau de cristallinité du PLA. Ces procédés comprennent l'utilisation d'agents nucléants, de plastifiants, ou de combinaisons d'agents plastifiants et de nucléation. La cristallisation du PLA à l'état fondu se présente sous deux formes cristallines légèrement différentes connues sous les noms α et α'. Cette étude compare la capacité d'auto-nucléation de ces deux formes cristallines par auto-nucléation. Ceci est réalisé en comparant les températures de cristallisation lors du refroidissement des échantillons préalablement cristallisés à diverses températures, puis de nouveau chauffé à une température dans la plage de fusion partielle du PLA. Dans la deuxième étape, l'effet des paramètres cinétiques et le poids moléculaire du PLA sur l'efficacité de nucléation des PLA phases cristallines a été étudié. Cette partie de l’étude ouvre une nouvelle voie pour comprendre le rôle des modifications cristallines du PLA qui mènent aux conditions optimales pour la cristallisation du PLA. La mise en forme des polymères implique des contraintes de cisaillement et d’élongation, ce qui implique une cristallisation induite par l’écoulement et la solidification qui s’en suit. Les propriétés mécaniques des produits finals dépendent du degré de cristallisation et de la nature des cristaux formés. Par conséquent, l'optimisation du procédé nécessite une bonne compréhension de la façon dont l’écoulement influence la cristallisation. Le type d'écoulement peut jouer un rôle important sur la cristallisation. Par exemple, l'écoulement élongationnel provoque l’orientation et l’étirement des molécules dans le sens de l'extension, comme dans le cas de la mise en forme de fibres et le soufflage de film, en aidant le processus de cristallisation induite par l'écoulement. Une littérature abondante existe sur la ii cristallisation des thermoplastiques classiques induite par l'écoulement. Cela dit, moins d'attention a été accordée à l'effet de l'écoulement de cisaillement et d'allongement sur la cristallisation du PLA. Comme étudié dans la dernière partie de ce document, l'effet du poids moléculaire sur la cristallisation induite par cisaillement du PLA est rapporté. Pour cela, trois différents PLA à faible, moyen et haut poids moléculaire ont été préparés par réaction d'hydrolyse. Ensuite, en utilisant un rhéomètre oscillatoire, l’effet du cisaillement sur la cinétique de cristallisation du PLA a été examiné.
Abstract : Poly(lactic acid), PLA, is a biocompatible and biodegradable polymer that can be produced from renewable resources. As a result, it has raised particular attention as a potential replacement for petroleum-based polymers. It is an aliphatic polyester with properties such as high modulus, high strength, and biocompatibility and is thus a promising material for various applications such as implants, drug encapsulation, and packaging. In the wake of low glass transition temperature, PLA has a low heat resistance and its application is limited to those not associated with high temperatures. In addition, this polymer suffers from a low degree of crystalinity. Increasing the crystallization rate in many processing operations, such as injection molding, is required. So far, many routes have been found to improve the crystallinity of PLA. These methods include using nucleating agents, plasticizers, and combination of nucleating agents and plasticizers together. PLA crystallization in the melt state results in two slightly different crystalline forms known as α and α’forms. This thesis compares the self-nucleation ability of these two crystal forms by self-nucleation. This is achieved by comparing crystallization temperatures upon cooling for samples previously crystallized at various temperatures and then re-heated to a temperature in the partial melting range for PLA. In the second step, we study the effect of molecular weight of PLA on the nucleation efficiency of PLA crystalline phases. This part of the investigation opens a new pathway to understand the role of PLA crystalline phases on the optimal condition for its crystallization kinetics. Polymer processing operations involve mixed shear and elongational flows and cause polymer molecules to experience flow-induced crystallization during flow and subsequent solidification. The mechanical properties of the final products are significantly dependent upon the degree of crystallization and types of formed crystals. Therefore, optimization of any polymer process requires a good understanding of how flow influences crystallization. The type of flow can play a significant role in affecting crystallization. For example, elongational flow causes molecules to orient and stretch in the direction of extension, as in the case of fiber spinning and film blowing, helping the process of flow-induced crystallization. An extensive body of literature exists on flow-induced crystallization of conventional thermoplastics. Having said that, less attention has been paid to the effect of shear and elongational flow on the PLA crystallization kinetics. As investigated in the final part of this thesis, the effect of iv molecular weight on the shear-induced crystallization of PLA is reported. For this, low, medium and high molecular-weight PLAs were prepared from a high molecular weight one by a hydrolysis reaction. Next, by means of a simple rotational rheometry, effect of the shear flow was examined on the crystallization kinetics of these three PLAs.

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36

Lusardi, Marcella R. (Marcella Rose). "Acid-base catalysts for polycondensation of acetaldehyde in flow." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/101563.

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Thesis: S.M., Massachusetts Institute of Technology, Department of Materials Science and Engineering, 2015.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 71-74).
Acetaldehyde is used as a bio-oil model compound in a polycondensation reaction over two acid-base catalysts, pelletized Evonik P25 TiO₂ and an activated hydrotalcite-like compound (HTlc), to produce high molecular weight molecules in the transportation fuel range. The catalytic performance of these materials is evaluated in a gas phase, atmospheric flow system with a packed bed microreactor designed to mimic process conditions in one step of the overall bio-oil upgrading scheme. The HTlc is activated through calcination at 500 °C followed by rehydration in decarbonated H₂O, generating the active acid-base hydroxyl pairs. Materials are characterized through XRD, low temperature N₂ adsorption-desorption isotherm experiments, TGA, and XPS. In initial experiments, high conversions are achieved but all converted acetaldehyde forms carbonaceous deposits on the catalyst surfaces over a range of temperatures and residence times. When the catalyst bed is reduced by 80%, decreasing both residence time and vapor-solid contact area, high conversions are maintained and the production of liquid phase condensation products is observed on the order of seconds. While yields are low, it is promising that tuning the packed bed results in decreased deposits and generation of liquid phase products. Further adjustments of reaction parameters and catalyst activity are of interest as future work, including shorter residence times and bed lengths, co-feeding a reaction inhibitor, and specific catalyst syntheses for control over active sites.
by Marcella R. Lusardi.
S.M.

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37

Tyagi, P. K. "Linear Instability Of Laterally Strained Constant Pressure Boundary Layer Flows." Thesis, Indian Institute of Science, 2001. http://hdl.handle.net/2005/265.

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The linear instability of laterally diverging/converging flows is an important aspect towards understanding the laminar-transition process in many viscous flows. In this work the linear instability of constant pressure laterally diverging/converging flow has been investigated. The laminar velocity field for laterally diverging/converging flows, under the source/sink approximation, has been reduced to two-dimensional flows. This reduction is alternative to the Mangier transformation used earlier. For a constant pressure laterally strained flow, the laminar velocity is found to be governed by the Blasius equation for flow over a flat plate. The non-parallel linear instability of constant pressure laterally strained flows has been examined. The instability equation is found to be same as that for the Blasius flow. This implies that the stability is same as that for the Blasius flow. A lateral divergence/convergence is shown to alter the Reynolds number from that in a two-dimensional flow. The instability of a laterally converging/diverging flow thus can be obtained from the available results for the Blasius flow by scaling the Reynolds numbers. This leads to the result that while a diverging flow is more unstable than the Blasius flow, a converging flow is more stable. Some additional relevant results are also presented.

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Sharp, Justin. "The structure and dynamics of Columbia Gorge gap flow revealed by high-resolution numerical modeling /." Thesis, Connect to this title online; UW restricted, 2005. http://hdl.handle.net/1773/10020.

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39

Fresconi, Frank. "Flow patterns and convective dispersion in the conducting airways of the human lung." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 145 p, 2007. http://proquest.umi.com/pqdweb?did=1362534221&sid=10&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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40

Menon, Anilkumar S. "Flow dynamics in a model of the large airways." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=72009.

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Oscillatory velocity profiles and the pressure-flow relationship were measured in a 3:1 scale rigid model of the human central airways. A reciprocating pump provided flows with frequencies of 0.25, 1, 2 and 4 Hz and tidal volumes of 300, 500 and 1500 mL giving tracheal Womersley numbers up to 31 and peak tracheal Reynolds numbers up to 17000. A hot wire anemometer was used to measure velocities along two perpendicular diameters (one in the plane of the model and the other in the plane perpendicular to the model) at 10 stations distributed through the model. Velocities were also measured with and without a model larynx and with tracheal intubation in steady inspiratory flows. The flow distribution to the five lobar bronchi was identical in all experiments.
Oscillatory velocity profiles were compared with the steady velocity profiles at nearly identical Reynolds numbers. The flow in a branch was quasi-steady below a critical Strouhal number in agreement with an order of magnitude analysis. For quasi-steady oscillatory flows the velocity profile developed from an initially flat shape to the profiles characteristic of steady flow in branching tubes. Flows that were not quasi-steady exhibited relatively flat profiles over the entire respiratory cycle. The effects of tidal volume, frequency and the geometry of the airways on the velocity profiles were determined.
While the larynx produced a significant jet within the trachea it had no effect on the velocity profiles beyond the carina. The presence of a concentric endotracheal tube located halfway between the glottis and the carina had little effect on the velocity profiles in the main stem and the lobar bronchi. Inserting the tube further into the trachea altered the velocity profiles in the right upper lobar bronchus.
In oscillating flow the pressure was essentially uniform around the periphery of a branch in strong contrast to the results for steady flow. The pressure drop in oscillating flow was much larger than the pressure drop in steady flow at an equivalent flow rate. The functional form of the relationship between the pressure drop across the different branches of the model and the tracheal Reynolds number was similar to that suggested by earlier researchers, however the coefficients were very sensitive to the geometry of the model.

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Beausoleil-Morrison, Ian David. "The adaptive coupling of heat and air flow modelling within dynamic whole-building simulation." Thesis, University of Strathclyde, 2000. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21137.

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This thesis is concerned with advancing the modelling of indoor air flow and internal surface convection within dynamic whole-building simulation. The path taken is the conflation of computational fluid dynamics (CFD) techniques with dynamic whole-building simulation, with an accurate treatment of the co-dependencies between these modelling domains. Two flow responsive modelling techniques were devised and implemented within the ESP-r simulation program to achieve the research objectives. The adaptive convection algorithm enhances ESP-r's thermal simulation domain by dynamically controlling the simulation of internal surface convection. Empirical methods were extracted from the literature and a new method for characterizing mixed flow convective regimes was created to provide the algorithm with a basis of 28 convection coefficient correlations. Collectively these methods can calculate convection coefficients for most flows of practical interest. Working with this suite of correlations, the algorithm assigns appropriate equations to each internal surface and adapts the selection in response to the room's evolving flow regime. The adaptive conflation controller manages all interactions between the thermal and CFD modelling domains. The controller incorporates the latest turbulence modelling advancements applicable for room air flow simulation and possesses a suite of handshaking and thermal boundary condition treatments. The job of this adaptive conflation controller is to monitor the evolving thermal and air flow conditions in the room and dynamically select an appropriate combination of modelling approaches for the prevailing conditions. The two control schemes implemented to demonstrate the controller make use of a double-pass modelling approach. Each time-step that the thermal domain handshakes with CFD, the adaptive conflation controller performs an investigative simulation to approximate the room's flow and temperature field. Using these estimates, the controller calculates dimensionless groupings to determine the nature of the flow (forced, buoyant, mixed, fully turbulent, weakly turbulent) adjacent to each internal surface. This information is used to select suitable boundary condition treatments for each surface. A second CFD simulation is then performed using the refined modelling approach to more accurately resolve the room's air flow and temperature distribution, and to predict surface convection. In order to protect the thermal domain, a two-stage screening process is used to assess (and where necessary reject) the CFD-predicted surface convection estimates. These adaptive modelling techniques advance the modelling of indoor air flow and internal surface convection within whole-building simulation.

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Kuang, Xingxing, and 匡星星. "Air and water flows induced by water level change in aquifers." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/196080.

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The study of air and water flows induced by water level changes is important for a better understanding of water release in response to pumping in unconfined aquifers and give new insights into pumping test data analysis. To improve the unsaturated flow and air-water two-phase flow numerical modeling of unconfined aquifer pumping tests, an improved unsaturated hydraulic conductivity model and a new relative air permeability model were proposed. A synthesis of the literature on subsurface airflow induced by natural forcings was presented to provide a better understanding of the generated airflow and its importance in environmental and engineering applications. A literature review was carried out to study the naturally occurring subsurface airflow. Analytical studies were carried out to derive the improved unsaturated hydraulic conductivity model and the new relative air permeability model. Experimental studies were conducted to investigate the air and water flows induced by drainage and pumping and numerical simulations were carried out using TOUGH2 and TOUGH2-MP to interpret the experimental data. Numerical models for unconfined aquifer pumping test analysis were built with TOUGH2-MP to investigate the effect of heterogeneity on pumping test results. The study of relative permeability models found that the relative permeabilities predicted by the proposed models are in better agreement with experimental data than existing models. Experimental and numerical investigations on air and water flows induced by drainage and pumping found that significant negative air pressure can be generated in a two-layered system with a low-permeability upper layer. The negative air pressure increases very fast after the start of pumping or drainage, reaches a maximum, and then gradually recovers to atmospheric pressure. The generated negative air pressure can significantly reduce the drainage of water from the column and increase the drawdown. Numerical studies of the effects of local heterogeneity on unconfined aquifer pumping test results found that the drawdown in an unconfined aquifer with a low-permeability zone is significantly greater than that of the homogeneous aquifers but the impact of the low-permeability zone diminishes in the long-term production period. This study presents state of knowledge on naturally occurring subsurface airflow and its implications, proposes improved and new relative permeability models for unsaturated flow and multiphase flow modeling, and offers new insights into the effect of air on water release and unconfined aquifer pumping test data analysis. The present study not only has theoretical significance but also has engineering implications.
published_or_final_version
Earth Sciences
Doctoral
Doctor of Philosophy

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43

Jouini, Dhafer Ben Mahmoud Carleton University Dissertation Engineering Mechanical. "Experimental investigation of the ventilation air flow properties in an office space." Ottawa, 1992.

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44

Sherwood, Julia Merryn. "Modelling minewater flow and quality changes after coalfield closure." Thesis, University of Newcastle Upon Tyne, 1997. http://hdl.handle.net/10443/314.

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The changes that have taken place in the British Coal Industry over the last five years have meant that in many coalfileds the last deep mines have closed. When a coalfield is abandoned and dewatering ceases, groundwater levels rebound, threatening surface waters with polluting discharges. However, the sparse data sets available limit modelling with existing techniques. A lumped parameter model GRAM (Groundater Rebound in Abandoned Mineworkings) has been developed. This model conceptualises a coalfield as a group of 'ponds'. Each pond is an area of the coalfield that has been extensively worked and can be considered as a single hydraulic unit. The ponds are connected by pipes which represent major inter-connecting roadways along which flow is assumed to be turbulent. Discharge to the surface is also represented using pipes. Flow through the pipes can be calculated using the Prandtl and Nikuradse of the Colebrook-White pipeflow equations. The storage coefficient can vary vertically to represent both worked Coal Measures and the intervening unworked strata. GRAM is able to predict the timing and volume of discahrges. An iron component gives an indication of the water quality evolution of the discahrges. Monte Carlo simulation allows the variables that have most error in their estimation to be represented by probability distributions. The Dysart-Leven Coalfield in eastern Fife, Scotland has not been mined since 1985. However, dewatering has continued to protect the workings in the Frances Colliery. In 1994 British Coal decided the Frances would never reopen, there is therfore no longer a need to continue dewatering. GRAM has been used to produce estimates of the quantity, timing and location of dischargges from the Dysart-Leven Coalfield should pumping cease. MODFLOW has also been applied to the coalfield with less success. Water quality modelling was also attempted using GRAM's iron component, however, conclusive results will not be obtained until the three variables over which ther is most uncertainty have been calibrated against existing discharges.

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45

Lee, Wing-chi Steven. "Analytical study of wind flow and pollutant dispersion past hills /." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk:8888/cgi-bin/hkuto%5Ftoc%5Fpdf?B22752948.

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46

King, Matthew James Stuart. "Experimental and modelling studies of transient slug flow." Thesis, Imperial College London, 1998. http://hdl.handle.net/10044/1/8270.

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47

Martins, Pedro Miguel Gaspar. "Essays on the macroeconomic management of foreign aid flows in Africa." Thesis, University of Sussex, 2010. http://sro.sussex.ac.uk/id/eprint/6286/.

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The main motivation of this thesis is to contribute to the literature on the macroeconomic effects of foreign aid flows. It consists of four empirical papers, investigating the two main channels through which aid flows impact the recipient economy: (i) the fiscal sector, and (ii) the real exchange rate. The first paper is concerned with the impact of aid on government expenditure, domestic revenues and borrowing. It uses a traditional fiscal response framework with annual data for Ethiopia. The second paper also focuses on the fiscal sector but uses a recently compiled quarterly fiscal dataset and the cointegrated vector autoregression methodology. The main result arising from both papers is the strong correlation between aid inflows and domestic borrowing, possibly as a strategy to smooth unpredictable and volatile aid inflows. Aid is positively correlated with government expenditures, but there is little evidence of tax displacement. There is also evidence of aid heterogeneity, as grants and loans induce different effects. The third paper assesses the impact of foreign aid on the Ethiopian real exchange rate, which is a common measure of external competitiveness. It uses a quarterly macroeconomic dataset and applies two distinct methodologies: (i) single-equation cointegration models, and (ii) an unobserved components model. The results do not provide support for the ‘Dutch disease' hypothesis. The fourth paper investigates the extent to which foreign aid is ‘absorbed' and ‘spent'. The empirical analysis uses a panel of 25 African low-income countries and applies recently developed panel cointegration techniques. The findings suggest that aid is fully spent while absorption is higher than previously estimated.

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Morgen, Brian A. "Virginia Gravity Flow Winery: A Transformative Journey." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/83895.

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This thesis is embodied by the design of a new gravity flow winery on the eastern slopes of the Blue Ridge Mountains in Northern Virginia. The 100 acre site is home to an existing winery with grape vines aged over a decade. From its initial inception, this thesis has been in part a response to the rapidly growing wine industry in Virginia and the typical ad hoc architecture associated with the wineries serving the state. The swelling interest in the culture of wine has sparked an evolution of the role of wineries. The winery of today is both an establishment for the production of wine as well as a venue for the enjoyment of its product and the delight of its natural setting. Creating a dialogue between site and visitor via thoughtful engagement of earth, air and sky is key for establishing a sense of place. The winery at the heart of this thesis is the quintessence of these ideals. The architecture of this winery embraces the steps of gravity flow winemaking, which aims to preserve the integrity of the grapes by utilizing gravity instead of electric pumps. The design seeks to make these steps perceivable and understandable, taking a visitor from the wind swept heights of the mountainside to the cool air of the winery's subterranean vaults and back again. From vine to glass and from layperson to student of wine, this shared journey engenders a transformation of both grape and visitor.
Master of Architecture

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Saxena, Gaurav. "Air flow separation over wind generated waves." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 235 p, 2007. http://proquest.umi.com/pqdweb?did=1251900711&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Assemi, Shoeleh 1963. "Use of flow field-flow fractionation for the characterisation of humic substances." Monash University, Dept. of Chemistry, 2000. http://arrow.monash.edu.au/hdl/1959.1/9028.

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Dissertations / Theses on the topic 'Flow aid'

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