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Koch, Kristine. "Methods for studying starch characteristics /." Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5487-5.pdf.
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III, Howard Joseph S. "Improved Methods for Modeling Dynamic Stage Characteristics." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/33391.
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An analytical investigation of dynamic compressor characteristics was conducted with the goal to make fundamental improvements in the modeling of dynamic compressor stage characteristics. It was determined that present state-of-the-art in modeling dynamic compressor stage characteristics is the use of steady-state characteristics derived from flow model calculations, with first-order time lag response functions applied to account for dynamic departures from the steady and quasi-steady performance predictions.
This investigation developed a blade frequency response function (FRF) method for describing the dynamic blade response. Once the frequency response function of a blade row has been determined, any time or spatially dependent, non-uniform flow can be applied and the model will predict the dynamic blade response.
The first step of this research was to develop FRFs based on first-order lag equations and to test the method using these simple transfer functions. The next step was to develop FRFs based on a dynamic blade lift model for a simple, idealized compressor blade row model. It was found that chord length has a strong influence on the FRF, which is related to the fluid transport time through the blade passage. The final step was to incorporate experimental data obtained from a study of dynamic wake response of an isolated rotor. It was assumed that the wake response was well correlated with the dynamic lift response of a blade row.
It was found that aerodynamic loading, distortion strength, and span position all influence the frequency response functions, which differ greatly from simple first-order lag equations. It was determined that a number of FRFs are needed to describe the dynamic blade response accurately.<br>Master of Science
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Shaner, Samuel Christopher. "Transient method of characteristics via the Adiabatic, Theta, and Multigrid Amplitude Function methods." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/92092.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Nuclear Science and Engineering, 2014.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (pages 147-149).<br>In this thesis, we investigated the Adiabatic, Theta, and Multigrid Amplitude Function (MAF) methods for solving the Method of Characteristics (MOC) formulation of the time-dependent neutron transport equation. The transient transport versions of the 2D LRA and C5G7 benchmarks were used to assess the performance and accuracy of these methods. We began by deriving the CMFD-accelerated MOC algorithm in 2D steady state form and examining the effects of various MOC and CMFD parameters on eigenvalue convergence. The C5G7 problem showed similar acceleration performance for 2, 4, and 7 CMFD energy group structures. CMFD meshes at or near the pin-cell level resulted in the greatest speedups of 15-45x in run time and 30-240 x in number of MOC iterations for both problems. A relaxation factor on the nonlinear diffusion coefficient was required to maintain stability for both problems with optimum values between 0.4-0.7. A sensitivity study was conducted on the C5G7 and LRA transient problems to understand the effects of time step and spatial mesh sizes on the solution accuracy and run time performance. The shape function time step size had a large effect on the solution accuracy for the MAF and Theta methods in solving the LRA problem. All methods showed moderate sensitivity to the amplitude function step size, where increasing step size shifted the peak power to earlier times. The coarse mesh size did not have a significant effect on solution accuracy, but meshes on the pin-cell level were clearly preferred to reduce run time. The overall run time performance between the three methods was mixed. The MAF and Theta methods displayed ~84% speedup over the Adiabatic method for the LRA problem, but all methods had similar run times for the C5G7 problem. This inconsistency is likely due to the more drastic flux shape change during the LRA transient and the ability of the MAF and Theta methods to more accurately treat the flux shape temporal derivative. These results demonstrate that the Adiabatic, Theta, and MAF methods are computationally efficient methods for solving the time-dependent neutron transport equation and warrant further investigation. There are clear advantages to each method and the optimal method will likely depend on the transient characteristics of the problem being studied.<br>by Samuel Christopher Shaner.<br>S.M.
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King, James F. "Dimension characteristics for invariant measures." Diss., Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/28788.
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Ardayfio, Mark Ayiety 1973. "Methods for capturing design intent using key characteristics." Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/9906.
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Ottosson, Anton, and Viktor Karlstrand. "Gaussian Process Methods for Estimating Radio Channel Characteristics." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-289449.
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Gaussian processes (GPs) as a Bayesian regressionmethod have been around for some time. Since proven advant-ageous for sparse and noisy data, we explore the potential ofGaussian process regression (GPR) as a tool for estimating radiochannel characteristics.Specifically, we consider the estimation of a time-varyingcontinuous transfer function from discrete samples. We introducethe basic theory of GPR, and employ both GPR and its deep-learning counterpart deep Gaussian process regression (DGPR)for estimation. We find that both perform well, even with fewsamples. Additionally, we relate the channel coherence bandwidthto a GPR hyperparameter called length-scale. The results show atendency towards proportionality, suggesting that our approachoffers an alternative way to approximate the coherence band-width.<br>Gaussiska processer (Gaussian processes,GPs) har länge använts för Bayesiansk regression. Då de visat sigfördelaktiga för gles och brusig data utforskar vi möjligheternaför GP-regression (Gaussian process regression, GPR) som ettverktyg för att estimera egenskaper hos radiokanaler.Isynnerhetbetraktasskattningaventidsvarierandeöverföringsfunktion utifrån diskreta samplingar. Vi presenterarden grundläggande teorin kring GPR, och använder både GPRoch dess djupinlärningsmotsvarighet DGPR (deep Gaussian pro-cess regression) för skattning. Båda ger goda resultat, även när samplingarna är få. Utöver detta så relaterar vi koherens-bandbredden hos en radiokanal till en hyperparameter i GPR-modellen. Resultaten visar på en tendens till proportionalitet,vilket antyder att vår metod kan användas som ett alternativt sätt att approximera koherensbandbredden.<br>Kandidatexjobb i elektroteknik 2020, KTH, Stockholm
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Baptista, Antonio E. de M. "Solution of advection-dominated transport by Eulerian-Lagrangian methods using the backwards method of characteristics." Thesis, Massachusetts Institute of Technology, 1987. http://hdl.handle.net/1721.1/14946.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1987.<br>MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.<br>Includes bibliographies.<br>by António Eugénio de Melo Baptista.<br>Ph.D.
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Costa, Surós Montse. "Geometric characteristics of clouds from ceilometer measurements and radiosounding methods." Doctoral thesis, Universitat de Girona, 2014. http://hdl.handle.net/10803/284084.
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Improving methods for automatic and continuous description of cloud has a huge importance in order to determine the role of clouds in climate and their contribution to climate change. The geometric characteristics of clouds, such as the cloud cover and the cloud vertical structure (CVS), including the cloud base height (CBH) which is linked to cloud type, are very important for describing the impact clouds have on the atmosphere.
It is presented a complete study of the cloud cover and the CBH above Girona (Spain) measured with a ceilometer, during the period 2007-2010. And a comparison of the CVS obtained from methods based on radiosonde profiles with estimations produced by ground-based active instruments (that is, the Active Remote Sensing of Clouds, ARSCL) over Southern Great Plains (USA) is presented in order to find the better approximation to the real vertical structure and reveal the strengths and weaknesses of the methods<br>La millora dels mètodes de descripció automàtica i contínua dels núvols és de gran importància a l’hora de determinar el paper de la nuvolositat en el clima i la seva contribució al canvi climàtic. Les característiques geomètriques de la nuvolositat, com ara la fracció coberta i la distribució vertical dels núvols (CVS), incloent l’altura de la base (CBH), són molt importants per tal de descriure l’impacte dels núvols en l’atmosfera.
Es presenta un estudi de la fracció coberta i la CBH a Girona, mesurada amb un ceilòmetre pel període 2007-2010; i una comparació de la CVS obtinguda a partir de mètodes basats en perfils de radiosondatges amb estimacions obtingudes d’instruments actius en superfície (l’Active Remote Sensing of Clouds, ARSCL) sobre Southern Great Plains (EUA) per tal de trobar la millor aproximació a l’estructura vertical real i revelar les fortaleses i febleses dels mètodes utilitzats
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Luo, Zinan. "Improvement of Rubber Yield Related Characteristics using Different Breeding Methods." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1503047446349694.
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Wright, Barbara Ann. "Common Characteristics of the Superintendency as Identified by Exemplary Arizona Superintendents." Diss., The University of Arizona, 2009. http://hdl.handle.net/10150/195194.
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To be successful, future leaders of the school, district, or other levels will require very different characteristics than those expected of leaders in the last decade (Fullan, 2000). The purpose of this study was to identify the key characteristics needed by school district superintendents to meet the demands of this position in the twenty-first century. The key characteristics were identified by exemplary superintendents who had been recognized for their effectiveness. The ten most frequently identified characteristics were then analyzed for commonalities and anomalies. A selected group of survey respondents also participated in semi-structured interviews to develop an understanding of the context surrounding the characteristic selections.This study of the key characteristics of effective superintendent indicates that an effective Arizona school superintendent for the 21st century must be centered on having the capacity, knowledge and aspirations to develop a collaborative relationship-driven culture. This study suggested both quantitatively and qualitatively that the development of positive relationships with all educational stakeholders was imperative to the success of the superintendent. Practicing and future superintendents will need to have superior interpersonal skills to be successful in the 21st century. Practicing and future superintendents will need to have superior interpersonal skills and it is the responsibility of university programs and professional organizations to provide opportunities for the development of these skills.
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Wang, Rongzhu. "Characteristics of silver and germanium sulfide films studied by nanoindentation methods." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ63388.pdf.
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Richardson, Lesley. "Case-control study methods : response rates, respondent characteristics and nonresponse bias." Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=65967.
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Wang, Yanchun. "Simplified methods for determining dynamic characteristics of tall wall-frame buildings." Thesis, University of Hertfordshire, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323652.
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Hamwi, Sakher. "Approximate methods for predicting the lifting characteristics of wing-body combinations." Thesis, Cranfield University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.237555.
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Cook, Christopher R. "Methods to improve the vibration characteristics of joist supported floor systems." Thesis, Virginia Tech, 1990. http://hdl.handle.net/10919/42157.
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Kawamori, Naoki. "Sprint acceleration performance in team sports : biomechanical characteristics and training methods." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2008. https://ro.ecu.edu.au/theses/224.
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Sprinting is a fundamental activity in many team sports such as soccer, rugby, football, field hockey, and basketball. Specifically, the ability to rapidly increase sprint running velocity over short distances, which is often referrcd to as sprint acceleration ability, is of major importance to team-sport athletes since sprint efforts during team-sport matches are typically of short duration (e.g., 10-20 m, 2-3 s). Biomechanical characteristics of the acceleration phase of sprinting has previously been studied in track sprinters from a block start, but there is a dearth of research exploring tile biomechanieal charactcristics of sprint acceleration in team-sport athletes from starting positions that are specific to team-sport match situations (e.g., standing start). In addition, resisted sprint training such as weighted sled towing is a popular training modality that athletes often use in an effort to improve sprint acceleration ability, but its use is largely based on choaches' observation and lacks experimental evidence. In particular, the optimal training load for resisted sprint training is currently unknown. This thesis explored to fill the research gap in such areas.
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Erdem, Munire Tugba. "Modeling Diseases With Multiple Disease Characteristics: Comparison Of Models And Estimation Methods." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613531/index.pdf.
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Epidemiological data with disease characteristic information can be modelled in several ways. One way is taking each disease characteristic as a response and constructing binary or polytomous logistic regression model. Second way is using a new response which consists of disease subtypes created by cross-classification of disease characteristic levels, and then constructing polytomous logistic regression model. The former may be disadvantageous since any possible covariation between disease characteristics is neglected, whereas the latter can capture that covariation behaviour. However, cross-classifying the characteristic levels increases the number of categories of response, so that dimensionality problem in parameter space may occur in classical polytomous logistic regression model. A two staged polytomous logistic regression model overcomes that dimensionality problem. In this thesis, study is progressen in two main directions: simulation study and data analysis parts. In simulation study, models that capture the covariation behaviour are compared in terms of the response model parameter estimators. That is, performances of the maximum likelihood estimation (MLE) approach to classical polytomous logistic regression, Bayesian estimation approach to classical polytomous logistic regression and pseudo-conditional likelihood (PCL) estimation approach to two stage polytomous logistic regression are compared in terms of bias and variation of estimators. Results of the simulation study revealed that for small sized sample and small number of disease subtypes, PCL outperforms in terms of bias and variance. For medium scaled size of total disease subtypes situation when sample size is small, PCL performs better than MLE, however when the sample size gets larger MLE has better performance in terms of standard errors of estimates. In addition, sampling variance of PCL estimators of two stage model converges to asymptotic variance faster than the ML estimators of classical polytomous logistic regression model. In data analysis, etiologic heterogeneity in breast cancer subtypes of Turkish female cancer patients is investigated, and the superiority of the two stage polytomous logistic regression model over the classical polytomous logistic model with disease subtypes is represented in terms of the interpretation of parameters and convenience in hypothesis testing.
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Lundin, Fredrik. "Idiopathic Normal Pressure Hydrocephalus : Aspects on Pathophysiology, Clinical Characteristics and Evaluation Methods." Doctoral thesis, Linköpings universitet, Neurologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-84243.
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Introduction. Idiopathic normal pressure hydrocephalus (iNPH) is a condition with enlargement of the cerebral ventricular system and an intracranial pressure (ICP) within normal limits. Cerebrospinal fluid circulation is disturbed but the mechanisms behind the symptoms: gait and balance difficulties, cognitive dysfunction and micturition problems, are as yet mostly unexplained. Aim. In Studies I and II the aim was to investigate cerebral metabolism in the frontal deep white matter (FDWM) and the thalamus in iNPH using Magnetic Resonance Spectroscopy (MRS) before and after shunt surgery and to compare this with healthy individuals (HI). In Study III the aim was, by use of actigraphy, to measure motor function, energy expenditure and resting/sleeping time in iNPH patients before and after shunt surgery, in comparison with HI. In Study IV the aim was to study postural function using computerised dynamic posturography (CDP) before and after shunt surgery as well as in comparison with HI. Patients and Methods. In all studies the patients had a neurological examination and baseline bedside assessments of motor, balance and cognitive function were performed. Motor function was assessed using a motor score (MOS) consisting of the following items: 10 metre walk time in seconds and number of steps and TUG time in seconds and number of steps. MOS was considered significant if there was an increase of 5% or more. The HI were also tested for motor, balance and cognitive function. In Study I the patients (n=16) and the HI (n=15) were examined with MRS (absolute quantification) with voxels placed in the thalamus and in FDWM and compared with one another. In Studies III and IV the preoperative results of actigraphy and CDP respectively in patients (Study III n=33; study IV n=35) were compared with the HI: Study III, n=17; Study IV, n=16. The HI performed these examinations twice and the average was calculated. In Study II, 14 patients, and in Studies III and IV, 20 patients underwent shunt surgery and new MRS/actigraphy/CDP examinations were performed three months postoperatively and compared with the preoperative results. Results. In the patients decreased total N-acetyl compounds (tNA) and N-acetyl aspartate (NAA) were found in the thalamus compared to the HI. No metabolic differences were seen in the FDWM between the groups. Postoperatively there were no metabolic changes in the thalamus but an increased total Choline (tCho) and a borderline significant decrease in myo-inositol (mIns).During the day the patients took fewer steps and had also lower total energy expenditure (TEE) than the HI. There was no difference concerning resting/sleeping time between patients and the HI. Postoperatively there were no differences of either number of steps, TEE or time spent resting or sleeping compared with the preoperative state. Postural function was worse in the patients compared to the HI, this difference being more pronounced in tests measuring vestibular function, where loss of balance (LOB) was frequent. There was only a slight improvement in balance after shunt surgery. A positive response to the shunt operation was seen in 86% in Study II, 85% in Study III and 90% in Study IV. Conclusions. Our results suggest that the thalamus may be involved in the pathogenesis of iNPH. In contrast to others, we did not find any metabolic abnormalities in the FDWM, nor detect an increment of tNA or NAA postoperatively in the thalamus. The postoperative increase in tCho and borderline decrease in mIns in the FDWM might reflect a state of metabolic recovery since high tCho, a major component of the cell membrane, may be a sign of increased membrane turnover, and a decrease in mIns may indicate diminished gliosis. The low gait capacity seen in the iNPH patients was not surprising but well that time spent resting/sleeping did not differ from the HI. Another unexpected finding was the unchanged ambulatory activity after shunt surgery despite improvement in a point test to determine capacity to walk a short distance. We believe this could be due to strong habits that are difficult to break and/or shortage of rehabilitation after surgery. There was a profound postural dysfunction in the patients with many falls, especially in test situations intended to measure vestibular function. This implies that there is a central vestibular disturbance. The discrete improvement in postural function postoperatively was lower than previously reported.
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Swartz, Kent Olen. "Virtual Environment Usability Assessment Methods Based on a Framework of Usability Characteristics." Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/34890.
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Developing economical yet effective methods of incorporating usability engineering as an integral part of software engineering is a primary focus of human-computer interaction (HCI) research. However, much HCI research has focused primarily on inspecting and evaluating applications supporting command-line or graphical user interface (GUI) interaction styles. With the dramatic increase in virtual environment (VE) research in recent years, the HCI community is beginning to place an added emphasis on creating methodologies to ensure usability in VE development. While the demand for VE-specific usability engineering methods and criteria is dire as the amount of money invested by military, government, commercial, and industrial organizations continues to grow, widely accepted methodologies for assessing VE usability are, at this point in time, minimal. There has been a recent increase in research discussing the need of VE-specific usability engineering methodologies, but few research projects have concentrated their efforts on providing such methodologies. Therefore, application developers attempting to apply a user-centered design approach in constructing VEs must often perform largely ad-hoc assessments or in-house evaluations using existing non-VE-specific usability engineering methodologies.
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The primary focus of this research was to develop a method to guide usability engineering of VEs. The strategy used to develop this usability evaluation method was to modify existing usability evaluation methodologies to support VE development by leveraging the results of previous VE usability research performed at Virginia Tech and elsewhere. The result was a VE-specific usability evaluation methodology that encompasses two existing usability assessment techniques: usability inspections and formative evaluations. We applied this methodology to Crumbs, an immersive visualization VE developed at the National Center for Supercomputing Applications (NCSA).
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A multi-dimensional framework of VE usability characteristics was a topic of research at Virginia Tech. This framework provided the backbone for VE-specific modifications to the existing usability evaluation techniques proposed in this research. Framework design guidelines permitted usability specialists to perform guidelines-based usability inspections of Crumbs. Results gathered from the guidelines-based usability inspections were used not only to redesign the Crumbs user interface but also drive creation of a formative evaluation plan. Application of the methodology not only uncovered usability issues with Crumbs, but also provided invaluable information regarding the effectiveness of the methodology itself. We conclude this thesis by describing a usability evaluation methodology, called the Modified Concept Book Usability Evaluation Methodology, proposed to improve the usability evaluation methodology performed on Crumbs and other VEs. Our methodology was adapted from an established methodology for performing content analysis on a large volume of qualitative data.
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Because the realm of VEs is so vast and diverse in application domains and devices, we do not claim that our methodology supports an exhaustive usability evaluation of all VEs. However, the proposed technique is a first attempt at modifying existing usability evaluation methods, and therefore can be used as a launching pad for methodologies to evaluate other aspects of specific VE applications.<br>Master of Science
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Scherer, T., D. Slack, J. Watson, and F. Fox. "Comparison of Three Irrigation Scheduling Methods and Evaluation of Irrigation Leaching Characteristics." College of Agriculture, University of Arizona (Tucson, AZ), 1989. http://hdl.handle.net/10150/204858.
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Three methods were used to schedule irrigations on replicated plots at the Maricopa Ag Center using DPL 90 cotton. The three methods were: a soil water balance model based on historic consumptive use curves, a soil water balance model based on the Modified Penman Equation and daily weather (AZMET), and infrared thermometry using the C.W.S.I. A potassium-bromide conservative tracer was applied at selected sites in the plots to evaluate leaching characteristics. The irrigation scheduling test was duplicated at the Safford Experiment Station and is presented in another report. Results from the 1988 data indicate that there was no significant difference in yield between the 3 methods. There was a significant difference in water applied; the historic consumptive-use curves was the lowest and the Penman equation method was the highest.
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Scherer, T., D. Slack, J. Watson, and F. Fox. "Comparison of Three Irrigation Scheduling Methods and Evaluation of Irrigation Leaching Characteristics." College of Agriculture, University of Arizona (Tucson, AZ), 1990. http://hdl.handle.net/10150/208305.
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Three methods were used to schedule irrigations during 1989 on replicated plots at the Maricopa Ag Center using DPL 90 cotton. This is a continuation of the research initiated in 1988 using the same field The three methods were; a soil water balance model based on historic consumptive use curves, a soil water balance model based on the Modified Penman Equation and daily weather (AZMET), and infrared thermometry using the C.W.S.I. A potassium- bromide conservative tracer was applied at selected sites in the plots to evaluate leaching characteristics. The irrigation scheduling test was again duplicated at the Safford Experiment Station and is presented in another report. Results from this years data indicate that there was no significant difference in yield among the three methods. However, as in 1988 there was a significant difference in water applied with historic consumptive use (ERIE) the lowest and the Penman equation method (CHECKBOOK) the highest.
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Scherer, Tom, Don Slack, Jack Watson, and Fred Fox. "Comparison of Three Irrigation Scheduling Methods and Evaluation of Irrigation Leaching Characteristics." College of Agriculture, University of Arizona (Tucson, AZ), 1991. http://hdl.handle.net/10150/208344.
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Three methods were used to schedule irrigations during the 1990 growing season on replicated plots at the Maricopa Ag Center using DPL 90 cotton. This is the final report of the research initiated in 1988. The three methods were: a soil water balance model based on historic consumptive use curves (ERIE), a soil water balance model (AZSCHED) based on the Modified Penman Equation and daily weather (AZMET), and infrared thermometry using the Crop Water Stress Index (CWSI). A potassium- bromide conservative tracer was applied at selected sites in the plots to evaluate leaching characteristics. The irrigation scheduling test was again duplicated at the Safford Experiment Station and is presented in another report. Results from this years data indicate that there was no significant difference in yield between the 3 methods. Also, there was no significant difference in the amount of applied irrigation water. The AZSCHED and ERIE methods will be developed into Extension educational tools and released for use by growers.
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Payne, Janette Elizabeth. "Relationship between psychosocial characteristics of clients and outcomes of dietary intervention methods." Thesis, Queensland University of Technology, 2000. https://eprints.qut.edu.au/36767/1/36767_Payne_2000.pdf.
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This study contributed to best practice dietary management of clients with heart disease in a number of ways. It compared the effectiveness of five different styles of delivery of dietary intervention in clients with heart disease. It considered the associations between pyschosocial and other individual characteristics and dietary intervention outcomes and reviewed the usefulness of many currently recommended outcome measures. Resources and recommendations were also developed to allow the incorporation of the findings into clinical practice.
277 male clients with demonstrated coronary heart disease were recruited from The Prince Charles Hospital during 1998. Participants were allocated to five groups: individual counselling, single group session, multi-group sessions, handout only or study questionnaires only. Dietary intervention was provided to the first four groups. Demographic, anthropometric, biochemical, dietary and psychosocial data were collected from participants at baseline, 3 months and 6 months post intervention. A specially designed education resource 'Key to Healthy Heart Eating' was developed and used in the dietary intervention groups.
All interventions resulted in improvements or positive outcomes for some of the variables measured, with many achieving statistical significance as noted in the results section. Positive changes to clinical (total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides), anthropometric (body mass index, waist hip ratio), behavioural and psychosocial outcome measures occurred for many individuals over the 6 month study period. The 'questionnaires only' intervention was shown to be significantly less effective for promoting improvement in anthropometric outcome measures compared to the dietary interventions considered. However, between these dietary interventions, no clear difference in performance was seen consistently across all outcome measures.
Therefore, choice of delivery style can not be specified by the results of this study. The multitude and complexity of factors involved in dietary behaviour change and achievement of positive outcomes is supported and reinforced. Some associations between initial characteristics and final outcomes were suggested and further studies are recommended to clarify and explore these findings further. The results of this study indicate that the most feasible and outcome effective style of delivery for this target population is dependent on the individual's capacity to participate, their initial anthropometric, clinical, behavioural and psychosocial profile, and other factors such as their support network, and physical and mental status. A screening process to select the most appropriate form of dietary intervention for individual clients with heart disease was developed to assist practitioners in the clinical setting.
Due to changes in knowledge scores during the study and the high percentage of participants meeting desirable outcome criteria before intervention, the validity and usefulness of some of the outcome measures can be questioned. For example, the focus on reducing fat intake was not appropriate as many were already selecting a low fat diet. The study also highlighted the need for practitioners to focus more on the dietary fibre intake of participants and their perceived barriers to change, for example, their willingness to explore new foods. High scores for doctors in the health locus of control questionnaires demonstrated the important role doctors are perceived to play, and hence their inclusion and involvement to promote a collaborative and integrated team approach is encouraged. The importance of ongoing support and follow-up for these clients was also highlighted and recommended.
The education resource developed for use in the current study will provide a useful tool for clinicians providing dietary and lifestyle education to men with coronary heart disease. The proposed screening process and recommendations are also provided for dissemination to, and evaluation by, practitioners. Further research is encouraged to build upon these findings and continue contributing towards the development of best practice guidelines for the dietary management of clients with heart disease.
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Liu, Yi. "Numerical simulations of the aerodynamic characteristics of circulation control wing sections." Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/12051.
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Hornbeak, Jerrick L. "Teaching methods and course characteristics related to college students' desire to take a course." Diss., Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/1367.
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Evenden, M. P. "Assessment of the cutting characteristics of coal seams by in situ testing methods." Thesis, University of Nottingham, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381170.
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Hasan, Dalal. "Personality characteristics of dental students in Kuwait University associated with preferred teaching methods." Scholarly Commons, 2020. https://scholarlycommons.pacific.edu/uop_etds/3671.
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This study examined personality characteristics of dental students at Faculty of Dentistry at Kuwait University and investigated the relationships between personality characteristics of these students and their preferred teaching methods. In order to assess personality characteristics, The Myers-Briggs Type Inventory (MBTI) was used. For teaching method categorization Grasha’s (2002) classification was used. This research builds knowledge about personality traits as measured by the Myers-Briggs Type Inventory® of dental students in Kuwait. Further, it adds knowledge about teaching methods preferred by dental students. Two surveys, the Myers- Briggs Type Indicator® Form M and a brief learning preference for teaching methodology survey, served as data collection instruments. Twenty-seven out of 43 dental students were interested in participation. Twenty-three (53.4%) students completed both surveys. After the data were analyzed, no dominant personality types among the dental students surveyed was uncovered. There were, however, four types slightly more represented than others. This study did find some correlations between certain subgroups and preferences for teaching methods. The study also found that students perceived Hybrid and Demonstrator methods as both the most preferred and most beneficial. Overall, the findings support that there is association between personality and preferences of teaching method and there is a preference of a teaching method over the other in dental education in general.
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Paykina, Ekaterina, and Li Zhou. "What characteristics are suited to help choosing traditional or agile project management methods for software development projects?" Thesis, Umeå universitet, Handelshögskolan vid Umeå universitet (USBE), 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-54062.
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Nowadays, the nature of the projects has changed to be unique, uncertain, ambiguous,complex and innovative. It becomes hard to plan in advance the project progress, asdeviations from plans and unpredictable changes occur more frequently. This can bespecifically observed in the software development industry which needs to constantlymeet customers’ rapidly changed requirements. Traditionally, software projects aredeveloped through a plan-driven approach which emphasizes an overall project plan andcontrol process in terms of project management. Recently, this has been challenged byagile approach that focuses on flexibility to quickly meet changing requirements, andthese new agile methods provoked huge interest and got more and more popular andwidely applied especially in IT industry. However, the popularity does not mean theagile methods have advantage over traditional plan-based project management methods.In fact, both methods have own advantages and disadvantages and cannot be fullyreplaced by each other. Therefore, it becomes important and necessary for companymanagement to know how to select a suitable method for the new software developmentproject to get the maximum benefits.The purpose of this study is to describe different project management methods(traditional plan-driven and agile methods) and their various consequences for themanagement of software-development projects. Additionally, a more practical purposeis to suggest on what grounds a choice between methods may be made. Morespecifically, this research aims to provide the possible solution on how to selecttraditional plan-driven or agile project management method for managing a newsoftware development project. The research conducted a qualitative study in a casecompany of IT industry through several semi-structured interviews and questionnaireswith experienced and knowledgeable employees. It started with the analysis andcomparison of traditional and agile project management methods’ characteristics andapplication domains based on two specific examples (PROPS and Scrum) selected fromtraditional and agile project management methods respectively, in order to identify a setof preliminary outstanding characteristics which could be used to help IT company tochoose project management methods for new software development projects. Theempirical data obtained from interviews of case company was investigated to verifythese characteristics based on the literature review, and further adjusted thecharacteristics identification. After going through the whole research process, finallyresearchers identified the most suitable characteristics that were important both intheory and practice to examine on what ground a software development company needsto base the selection of project management methods. These suitable characteristics are:Project Complexity, Communication, Competencies and Requirements, in order to helpselect the best management way for the specific project.
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Liu, Ting. "METHODS DEVELOPMENT IN QUALITATIVE AND QUANTITATIVE PROTEOMICS." UKnowledge, 2008. http://uknowledge.uky.edu/gradschool_diss/838.
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Proteomics based on liquid chromatography coupled to mass spectrometry has developed rapidly in the last decade and become a powerful tool for protein mixtures analysis. LC-MS based proteomics involves four steps, sample preparation, liquid chromatography, mass spectrometry and bioinformatics. Improvements in each step have extended its applications to new biological research areas. This dissertation mainly focuses on method developments in both qualitative and quantitative proteomics.
The first part of this dissertation focuses on qualitative analysis of T. gondii Parasitophorous Vacuole Membrane (PVM) proteins, which is very important for T. gondii’s survival. The hypothesis of this study is that proteomic approaches coupled with immunoprecipitation using polyclonal antisera as affinity reagents can successfully characterize the proteome of the T. gondii PVM. The “Three-layer Sandwich Gel Electrophoresis” (TSGE) protocol, was developed to contend with efficient salt removal and protein concentration from challenging samples. Furthermore, the TSGE coupled to 2D-LC-MS/MS was proven to be effective with the proteomic analysis of complex protein mixtures like T. gondii whole cell lysate, allowing for high-throughput protein analysis from complex samples. By using the TSGE-2D-LC-MS/MS methodology, we successfully identified 61 proteins from the PVM samples and constructed the PVM proteome.
The second part of this dissertation describes a novel method for selecting an appropriate isocyanate reagent for potential quantitative proteomics application. Our hypothesis is alteration of isocyanate structure will change fragmentation pattern and ESI property of isocyanate modified peptides. The CID property of N-terminal modified peptides by phenyl isocyanate (PIC), phenethyl isocyanate (PEIC) and pyridine-3- isocyanate (PyIC) was systematically studied using LC-ESI-MS/MS. We observed that adjustment of isocyanate structure changed both ESI and fragmentation characteristic of modified peptides. We rationalized the decrease of protonation of PIC and PEIC modified peptides results from the neutral property of the both reagents. The electron withdrawing feature of PyIC leads to significant reduction of fragments during CID. Therefore, we designed a new isocyanate reagent, 3-(isocyanatomethyl) pyridine (PyMIC). The results revealed that PyMIC modified peptides had more suitable ESI properties and generated more sequence-useful fragments compared to PIC, PyIC and even unmodified peptides. PyMIC is a more appropriate labeling reagent for quantitative proteomics applications.
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Falagkaris, Emmanouil. "Lattice Boltzmann method and immersed boundary method for the simulation of viscous fluid flows." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/33165.
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Most realistic fluid flow problems are characterised by high Reynolds numbers and complex boundaries. Over the last ten years, immersed boundary methods (IBM) that are able to cope with realistic geometries have been applied to Lattice- Boltzmann methods (LBM). These methods, however, have normally been applied to low Reynolds number problems. In the present work, an iterative direct forcing IBM has been successfully coupled with a multi-domain cascaded LBM in order to investigate viscous flows around rigid, moving and wilfully deformed boundaries at a wide range of Reynolds numbers. The iterative force-correction immersed boundary method of (Zhang et al., 2016) has been selected due to the improved accuracy of the computation, while the cascaded LB formulation is used due to its superior stability at high Reynolds numbers. The coupling is shown to improve both the stability and numerical accuracy of the solution. The resulting solver has been applied to viscous flow (up to a Reynolds number of 100000) passed a NACA-0012 airfoil at a 10 degree angle of attack. Good agreement with results obtained using a body-fitted Navier-Stokes solver has been obtained. At moving or deformable boundary applications, emphasis should be given on the influence of the internal mass on the computation of the aerodynamic forces, focusing on deforming boundary motions where the rigid body approximation is no longer valid. Both the rigid body and the internal Lagrangian points approximations are examined. The resulting solver has been applied to viscous flows around an in-line oscillating cylinder, a pitching foil, a plunging SD7003 airfoil and a plunging and flapping NACA-0014 airfoil. Good agreement with experimental results and other numerical schemes has been obtained. It is shown that the internal Lagrangian points approximation accurately captures the internal mass effects in linear and angular motions, as well as in deforming motions, at Reynolds numbers up to 4 • 104. Finally, an expanded higher-order immersed boundary method which addresses two major drawbacks of the conventional IBM will be presented. First, an expanded velocity profile scheme has been developed, in order to compensate for the discontinuities caused by the gradient of the velocity across the boundary. Second, a numerical method derived from the Navier-Stokes equations in order to correct the pressure distribution across the boundary has been examined. The resulting hybrid solver has been applied to viscous flows around stationary and oscillating cylinders and examined the hovering flight of elliptical wings at low Reynolds numbers. It is shown that the proposed scheme smoothly expands the velocity profile across the boundary and increases the accuracy of the immersed boundary method. In addition, the pressure correction algorithm correctly expands the pressure profile across the boundary leading to very accurate pressure coefficient values along the boundary surface. The proposed numerical schemes are shown to be very efficient in terms of computational cost. The majority of the presented results are obtained within a few hours of CPU time on a 2.8 GHz Intel Core i7 MacBook Pro computer with a 16GB memory.
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Fan, Meng. "Stability of Academic Performance Across Science Subjects Among Chinese Students." UKnowledge, 2013. http://uknowledge.uky.edu/edp_etds/15.
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With data describing 110,520 eighth grade students from 592 junior high (middle) schools in China, a three-level hierarchical linear model was developed in this study to create a multivariate multilevel environment to examine (a) the effects of student-level and school-level variables on science achievement in four subject areas (science inquiry skills, biology, earth science, and physics) and (b) the consistency or stability of academic achievement across the four subject areas among students and among schools. Results indicated that (a) student characteristics, including gender, parental SES, time spent in learning, and the type of family separation, were related to high academic achievement in each of the four science subject areas, (b) no school characteristics were found to be significant factors to affect students’ academic performance in any of the four science subject areas, (c) both students and schools with high academic achievement in one subject area also showed high academic achievement in other subject areas, and (d) the consistency or stability of science performance over the four subject areas did not depend on student characteristics and school characteristics.
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Lam, Ka-kui Ringo. "Shoplifters in Hong Kong : a mixed methods analysis of their characteristics in probation setting /." Click to view the E-thesis via HKUTO, 2006. http://sunzi.lib.hku.hk/hkuto/record/B3727174X.
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Law, Amir A. "The relationships between noncognitive characteristics and student engagement| A sequential exploratory mixed methods study." Thesis, California State University, Fullerton, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3662871.
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<p> The purpose of this study was to explore the perceptions of students of color at an urban commuter university as they relate to the constructs utilized within the engagement literature and to the noncognitive student characteristics literature. Data were collected using the following instruments: William Sedlacek's Noncognitive Questionnaire (NCQ), items from the Beginning College Student Survey of Engagement (BCSSE), items from the National Survey of Student Engagement (NSSE), and individual and small group interviews. The key findings of this study revealed that noncognitive characteristics assisted students in (a) internalizing messages, (b) understanding systemic processes, and (c) identifying motivating factors. These findings underscore the importance of moving away from a monolithic understanding of engagement to a more complex consideration of the ways in which students interact with the campus environment. Furthermore, this study showed the importance of providing incoming students with the opportunity to build on noncognitive personal skills, experiences, and characteristics—assets that are not measured by traditional college entrance requirements such as high school grades or standardized test scores and that often have not been seen as being directly related to academic success. This can be accomplished through the development of curricular and co-curricular experiences that include comprehensive programs and activities as they pertain to internalizing key messages, determining motivators, and understanding systemic processes.</p>
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Lam, Ka-kui Ringo, and 林家駒. "Shoplifters in Hong Kong: a mixed methods analysis of their characteristics in probation setting." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2006. http://hub.hku.hk/bib/B3727174X.
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Lundqvist, Henrik. "Range characteristics and productivity determinants for reindeer husbandry in Sweden /." Uppsala : Reindeer Husbandry Unit, Swedish University of Agricultural Sciences, 2007. http://epsilon.slu.se/2007100.pdf.
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Coad, D. Stephen. "Outcome-dependent randomisation schemes for clinical trials with fluctuations in patient characteristics." Thesis, University of Oxford, 1989. http://ora.ox.ac.uk/objects/uuid:970a8103-24fc-496e-82c0-0645f2b4e9c4.
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A clinical trial is considered in which two treatments are to be compared. Treatment allocation schemes are usually designed to assign approximately equal numbers of patients to each treatment. The purpose of this thesis is to investigate the efficiency of estimation and the effect of instability in the response variable for allocation schemes which are aimed at reducing the number of patients who receive the inferior treatment. The general background to outcome-dependent allocation schemes is described in Chapter 1. A discussion of ethical and practical problems associated with these methods is presented together with brief details of actual trials conducted. In Chapter 2, the response to treatment is Bernoulli and the trial size is fixed. A simple method for estimating the treatment difference is proposed. Simulation results for a selection of allocation schemes indicate that the effect of instability upon the performance of the schemes can sometimes be substantial. A decision-theory approach is taken in Chapter 3. The trial is conducted in a number of stages and the interests of both the patients in the trial and those who will be treated after the end of the trial are taken into account. Using results for conditional normal distributions, analytical results are derived for estimation of the treatment difference for both a stable and an unstable normal response variable for three allocation schemes. Some results for estimation are also given for other responses. The problem of sequential testing is addressed in Chapter 4. With instability in the response variable, it is shown that the error probabilities for the test for a stable response variable can be approximately preserved by using a modified test statistic with appropriately-widened stopping boundaries. In addition, some recent results for estimation following sequential tests are outlined. Finally, the main conclusions of the thesis are highlighted in Chapter 5.
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Reiter, E. Miranda. "The Impact of Social Support, Psychosocial Characteristics, and Contextual Factors on Racial Disparities in Hypertension." Thesis, Utah State University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3683497.
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<p> Hypertension is a serious medical condition. Although men and women of all racial groups in the US suffer from high blood pressure, black women have the highest rates of hypertension. For instance, the age-adjusted prevalence of hypertension among black women ages 20 and over is 44.3, compared to 28.1 among white women, 40.5 among black men, and 31.1 among white men.</p><p> Past research has focused on SES and behavioral factors as potential explanations for blood pressure disparities between black and white women. But, even after controlling for such factors, considerable disparities remain. The goal of this research is to examine cultural and social factors that have been shown to increase blood pressure. Specifically, I examine social support, psychosocial characteristics, and contextual factors associated with race/ethnicity and hypertension, in hopes of explaining some of the disparities in high blood pressure between black and white women.</p><p> Using data from Waves I, III, and IV of the National Longitudinal Study of Adolescent Health (Add Health), I estimated a sequence of multinomial logistic regression models predicting prehypertension and hypertension in young adulthood. Cross-sectional models show that racial disparities in hypertension remain after controlling for social support, psychosocial characteristics, and contextual factors. In fact, the only covariate that substantially reduced the racial disparity in hypertension was body mass index (BMI), a fairly reliable measure of body fatness for most people. I also estimated a set of multinomial logistic regression models predicting odds of prehypertension and hypertension by adolescent and cumulative social support, as well as psychosocial, contextual, and behavioral factors. These models were included to determine if early life and/or cumulative factors and conditions would help explain racial blood pressure disparities not explained by adulthood factors. Findings show that none of the early life or cumulative social support, psychosocial, contextual, or behavioral factors helped to explain racial differences in prehypertension or hypertension. Even after controlling for these factors, black women are still 1.18 times more likely than white women to have prehypertension and over two times more likely to suffer hypertension.</p><p> Indeed, my findings indicate that, of the factors included in all these models, only race, age, and BMI were significant predictors of blood pressure. Also, BMI was the only factor to explain some of the disparities between black and white women. These results are similar to other studies that have examined racial health disparities, suggesting that simply being a black woman in US society may be unhealthy. The health effects of racism, discrimination, and other sources of stress faced disproportionately by black women are not easily measured by social science research, which is possibly why racial disparities in blood pressure have yet to be explained. Future research should also explore possible epigenetic effects introduced by the health conditions experienced by previous generations, as well as the influence of prenatal and early life environments.</p>
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Komarov, Alexander. "New methods for detecting dynamic and thermodynamic characteristics of sea ice from radar remote sensing." Institute of Electrical and Electronics Engineers, 2014. http://hdl.handle.net/1993/30225.
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This dissertation presents new methods for detecting dynamic and thermodynamic characteristics of Arctic sea ice using radar remote sensing.
A new technique for sea ice motion detection from sequential satellite synthetic aperture radar (SAR) images was developed and thoroughly validated. The accuracy of the system is 0.43 km obtained from a comparison between SAR-derived ice motion vectors and in-situ sea ice beacon trajectories. For the first time, we evaluated ice motion tracking results derived from co-polarization (HH) and cross-polarization (HV) channels of RADARSAT-2 ScanSAR imagery and formulated a condition where the HV channel is more reliable than the HH channel for ice motion tracking. Sea ice motion is substantially controlled by surface winds. Two new models for ocean surface wind speed retrieval from C-band SAR data have been developed and validated based on a large body of statistics on buoy observations collocated and coincided with RADARSAT-1 and -2 ScanSAR images. The proposed models without wind direction input demonstrated a better accuracy than conventionally used algorithms. As a combination of the developed methods we designed a wind speed-ice motion product which can be a useful tool for studying sea ice dynamics processes in the marginal ice zone.
To effectively asses the thermodynamic properties of sea ice advanced tools for modeling electromagnetic (EM) wave scattering from rough natural surfaces are required. In this dissertation we present a new analytical formulation for EM wave scattering from rough boundaries interfacing inhomogeneous media based on the first-order approximation of the small perturbation method. Available solutions in the literature represent special cases of our general solution. The developed scattering theory was applied to experimental data collected at three stations (with different snow thicknesses) in the Beaufort Sea from the research icebreaker Amundsen during the Circumpolar Flaw Lead system study. Good agreement between the model and experimental data were observed for all three case studies. Both model and experimental radar backscatter coefficients were considerably higher for thin snow cover (4 cm) compared to the thick snow cover case (16 cm). Our findings suggest that, winter snow thickness retrieval may be possible from radar observations under particular scattering conditions.
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Blacklock, Oliver S. "Characteristics of variation in production of normal and disordered fricatives using reduced-variance spectral methods." Thesis, University of Southampton, 2004. https://eprints.soton.ac.uk/420069/.
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Semeniuk, T. A. "Endothelium of the heart ventricles in human: its morphological characteristics and methods of its investigation." Thesis, БДМУ, 2022. http://dspace.bsmu.edu.ua:8080/xmlui/handle/123456789/19355.
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Ruckthongsook, Warangkana. "The Influence of Disease Mapping Methods on Spatial Patterns and Neighborhood Characteristics for Health Risk." Thesis, University of North Texas, 2017. https://digital.library.unt.edu/ark:/67531/metadc1062838/.
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This thesis addresses three interrelated challenges of disease mapping and contributes a new approach for improving visualization of disease burdens to enhance disease surveillance systems. First, it determines an appropriate threshold choice (smoothing parameter) for the adaptive kernel density estimation (KDE) in disease mapping. The results show that the appropriate threshold value depends on the characteristics of data, and bandwidth selector algorithms can be used to guide such decisions about mapping parameters. Similar approaches are recommended for map-makers who are faced with decisions about choosing threshold values for their own data. This can facilitate threshold selection. Second, the study evaluates the relative performance of the adaptive KDE and spatial empirical Bayes for disease mapping. The results reveal that while the estimated rates at the state level computed from both methods are identical, those at the zip code level are slightly different. These findings indicate that using either the adaptive KDE or spatial empirical Bayes method to map disease in urban areas may provide identical rate estimates, but caution is necessary when mapping diseases in non-urban (sparsely populated) areas. This study contributes insights on the relative performance in terms of accuracy of visual representation and associated limitations. Lastly, the study contributes a new approach for delimiting spatial units of disease risk using straightforward statistical and spatial methods and social determinants of health. The results show that the neighborhood risk map not only helps in geographically targeting where but also in tailoring interventions in those areas to those high risk populations. Moreover, when health data is limited, the neighborhood risk map alone is adequate for identifying where and which populations are at risk. These findings will benefit public health tasks of planning and targeting appropriate intervention even in areas with limited and poor-quality health data. This study not only fills the identified gaps of knowledge in disease mapping but also has a wide range of broader impacts. The findings of this study improve and enhance the use of the adaptive KDE method in health research, provide better awareness and understanding of disease mapping methods, and offer an alternative method to identify populations at risk in areas with limited health data. Overall, these findings will benefit public health practitioners and health researchers as well as enhance disease surveillance systems.
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Mahdi, Faiz M. "Comparison of porous media permeability : experimental, analytical and numerical methods." Thesis, Loughborough University, 2014. https://dspace.lboro.ac.uk/2134/16140.
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Permeability is an important property of a porous medium and it controls the flow of fluid through the medium. Particle characteristics are known to affect the value of the permeability. However, experimental investigation of the effects of these particle characteristics on the value of permeability is time-consuming while analytical predictions have been reported to overestimate it leading to inefficient design. To overcome these challenges, there is the need for the development of new models that can predict permeability based on input variables and process conditions. In this research, data from experiments, Computational Fluid Dynamics (CFD) and literature were employed to develop new models using Multivariate Regression (MVR) and Artificial Neural Networks (ANNs). Experimental measurements of permeability were performed using high and low shear separation processes. Particles of talc, calcium carbonate and titanium dioxide (P25) were used in order to study porous media with different particle characteristics and feed concentrations. The effects of particle characteristics and initial stages of filtration as well as the reliability of filtration techniques (constant pressure filtration, CPF and constant rate filtration, CRF) were investigated. CFD simulations were also performed of porous media for different particle characteristics to generate additional data. The regression and ANN models also included permeability data taken from reliable literature sources. Particle cluster formation was only found in P25 leading to an increase of permeability especially in sedimentation. The constant rate filtration technique was found more suitable for permeability measurement than constant pressure. Analyses of data from the experiments, CFD and correlation showed that Sauter mean diameter (ranging from 0.2 to 168 μm), the fines ratio (x50/x10), particle shape (following Heywood s approach), and voidage of the porous medium (ranging from 98.5 to 37.2%) were the significant parameters for permeability prediction. Using these four parameters as inputs, performance of models based on linear and nonlinear MVR as well as ANN were investigated together with the existing analytical models (Kozeny-Carman, K-C and Happel-Brenner, H-B). The coefficient of correlation (R2), root mean square error (RMSE) and average absolute error (AAE) were used as performance criteria for the models. The K-C and H-B are two-variable models (Sauter mean diameter and voidage) and two variables ANN and MVR showed better predictive performance. Furthermore, four-variable (Sauter mean diameter, the x50/x10, particle shape, and voidage) models developed from the MVR and ANN exhibit excellent performance. The AAE was found with K-C and H-B models to be 35 and 40%, respectively while the results of using ANN2 model reduced the AAE to 14%. The ANN4 model further decreased the AAE to approximately 9% compared to the measured results. The main reason for this reduced error was the addition of a shape coefficient and particle spread (fine ratio) in the ANN4 model. These two parameters are absent in the analytical relations, such as K-C and H-B models. Furthermore, it was found that using the ANN4 (4-5-1) model led to increase in the R2 value from 0.90 to 0.99 and significant decrease in the RMSE value from 0.121 to 0.054. Finally, the investigations and findings of this work demonstrate that relationships between permeability and the particle characteristics of the porous medium are highly nonlinear and complex. The new models possess the capability to predict the permeability of porous media more accurately owing to the incorporation of additional particle characteristics that are missing in the existing models.
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Valverde, Pellicer Laura. "Comparison of sensory characteristics, and instrumental flavor compounds analysis of milk produced by three production methods." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/5057.
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Thesis (M.S.)--University of Missouri-Columbia, 2007.<br>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 November 6, 2007 Includes bibliographical references.
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Mountain, Gary. "'Bite characteristics of children and the fidelity of testing methods as they apply to toy safety'." Thesis, University of Leeds, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.496138.
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Pandya, Tara M. 1984. "Long-Characteristics Methods with Piecewise Linear Sources in Space and Time for Transport on Unstructured Grids." Thesis, 2012. http://hdl.handle.net/1969.1/148326.
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The method of characteristics (MOC) is a deterministic transport method that has been applied to large-scale problems including those in reactor physics and radiative transfer. Long characteristics, (LC) methods, have been used extensively to discretize and solve transport problems in the spatial domain. There is a need for an equally adequate time-dependent discretization for these transport problems.
The new contributions from this research include the development of a space-time long characteristic (STLC) method with various source approximations including several that employ a piece-wise linear (PWL) approximation spatially. In the prism-PWL (PPWL) method the coefficient of each PWL spatial function is linear in time in each space-time cell. Along with STLC, a PWL-LC method is developed for steady-state problems in (x, y) and (x, y, z). The methods developed in this work use least-squares projections to determine the coefficients of their source approximations.
This work presents a detailed asymptotic analysis of the PWL-LC and STLC methods in the thick diffusion limit, which is of special interest in radiative transfer problems. This is the first such analysis reported for LC methods and these new methods are the first that are expected to perform well in this limit.
Results from test problems executed with a modified version of the Parallel Deterministic Transport code, PDT, show the PWL-LC and STLC methods are more accurate than current methods for streaming problems. From asymptotic analysis and test problems, it is found that the steady-state PWL-LC method is accurate in the thick diffusion limit with solutions similar to those of analogous discontinuous finite element method, DFEM, solutions. Similarly, the PPWL-STLC method is found to be accurate in time-dependent thick diffusive problems.
STLC is also a promising method for massively parallel applications because it permits the use of track-based sweeping, which appears to have significant advantages over cell-based sweeping. This is a key topic recommended for further research.
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YUN, YU YA, and 游雅筠. "Simulation Methods for Electromagnetic Characteristics of Grounding Electrodes." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/09104679834930269338.
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碩士<br>國立清華大學<br>電機工程學系<br>91<br>Taiwan’s Synchronous Radiation Research Center （SRRC） located at Hsinchu has been suffered with the multitripps of accelerator and with the instability of electron beam. Two possible reasons for the multitripping and beam instability are: the voltage fluctuation of power supply and the high frequency stray current leaked into the ground mesh or ground electrodes. The latter could interfere the control devices for the accelerator. Because both reasons have connection with ground electrodes, SRRC established a new one which grounding resistance was designed to be lower than 0.2Ω in 2002. Meanwhile SRRC investigated the original ground electrodes which are under the accelerator to look for improvements. However the research was deficient in simulations for ground electrodes, many judgments and suggestions was lack of the identification of theories.
To simulate Grounding Potential Difference (GPD), local researchers applied the Electro Magnetic Transient Program (EMTP) more frequently than the Current Distribution Electromagnetic Grounding and Soil Structure Analysis (CDEGS), the latter being a software designed specially for simulating GPD. In the mesh model of EMTP, the conductors of ground mesh are simulated as RL circuits, which neglects the interaction among conductors and the modeling requires precise estimation of parameters. Both can thus result in simulation error. As such, there is a necessity for applying of the softwares with special design for GPD simulation, such as CDEGS, which could be the future mainstream of GPD simulation.
Taiwan is presently lacking researches on the methods of GPD simulation, in particular for those specially designed softwares. What are their assumptions? Have their individual subroutines been tested for accuracy validation? Where are their sources for the simulation errors? All these demand in-depth research. More clearly, Taiwan needs a comprehensive literature on the computation methods for GPD simulation, as an important reference for the future GPD simulation and the overvoltage event diagnosis.
Consequently, the thesis firstly focuses on the potential fluctuation causing by the fault or inrush current which is injected into ground electrodes. Secondary it studies the potential fluctuation causing by the high-frequency current which is leaking into the ground. The former belongs to the grounding safety problems, and the latter belongs to the EMI topics. The thesis is divided into three folds, part 1 shall study the grounding simulation method of CDEGS. Part 2 shall compare different ground electrodes via simulation, including: the magnitude of ground electrode or injecting current, soil resistance coefficient, the depth of ground electrode and the position of injecting current etc.. This part also discusses a flat long row which is made up by cylinder conductors. Part 3 shall simulate the new ground electrodes of SRRC, and simulate the GPD between old and new ground electrodes while the kicker with high frequency of 830 kHz and large current of 6.5 kA is operating. The former simulates the low frequency, and the latter simulates the high frequency. Both are compared with the measurement results and the validities of the simulations are also discussed.
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Gast, James E. "Topology aware estimation methods for internet traffic characteristics." 2003. http://www.library.wisc.edu/databases/connect/dissertations.html.
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Ribeiro, Bruno F. "On the design of methods to estimate network characteristics." 2010. https://scholarworks.umass.edu/dissertations/AAI3409837.
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Social and computer networks permeate our lives. Large networks, such as the Internet, the World Wide Web (WWW), AND wireless smartphones, have indisputable economic and social importance. These networks have non-trivial topological features, i.e., features that do not occur in simple networks such as lattices or random networks. Estimating characteristics of these networks from incomplete (sampled) data is a challenging task. This thesis provides two frameworks within which common measurement tasks are analyzed and new, principled, measurement methods are designed. The first framework focuses on sampling directly observable network characteristics. This framework is applied to design a novel multidimensional random walk to efficiently sample loosely connected networks. The second framework focuses on the design of measurement methods to estimate indirectly observable network characteristics. This framework is applied to design two new, principled, estimators of flow size distributions over Internet routers using (1) randomly sampled IP packets and (2) a data stream algorithm.
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Jui-Lun, Chiang. "Analysis of Optical Waveguide Propagation Characteristics Using Finite Element Methods." 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-3007200619484500.
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Chiang, Jui-Lun, and 江瑞倫. "Analysis of Optical Waveguide Propagation Characteristics Using Finite Element Methods." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/02659015893037035376.
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碩士<br>國立臺灣大學<br>電信工程學研究所<br>94<br>In this research, we improve an optical waveguide mode solver based on the fi-
nite element method (FEM) and curvilineal hybrid edge/nodal elements, and
implement a nonlinear beam propagation method (BPM) numerical model
based on the related FEM scheme. The FEM mode solver is incorporated into
it the perfectly matched layer (PML) absorbing boundary condition and can
solve the leaky waveguide mode very accurately. We refine the algorithms of
the mode solver related to rigorous boundary setting involving perfect electric
conductor (PEC) and perfect magnetic conductor (PMC) and numerical
implementation of PMLs. The mode solver is further generalized to the analysis
of nonlinear waveguide modes for working together with the nonlinear
BPM model. Another FEM based mode solver for two-dimensional (2-D)
linear and nonlinear periodic optical waveguides is also implemented with
second order triangular elements. Periodic boundary conditions are properly
imposed in the propagation direction for efficient analysis. Numerical examples
considered in this research include circular waveguide, 3-D antiresonant
reflecting optical waveguide (ARROW), holey fibers of various numbers of air
holes, nonlinear directional coupler, and 2-D linear and nonlinear photonic
crystal waveguides. We in particular develop a scheme to present power flow
diagrams in the cross-sectional plane for leaky modes.