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Скуріхін, Владислав Ігорович. "Розвиток ресурсозберігаючих технологій раціонального струмознімання на міському електротранспорті." Thesis, Харківський національний університет міського господарства ім. О. М. Бекетова, 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/19886.
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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.22.09 – електротранспорт; Національний технічний університет "Харківський політехнічний інститут", Харків, 2015 р. Дисертаційна робота присвячена вирішенню актуальної науково-практичної задачі – розвитку ресурсозберігаючих технологій раціонального струмознімання на міському електротранспорті за рахунок застосування в системі струмознімання альтернативних матеріалів і удосконаленої конструкції сталеалюмінієвого контактного проводу. Проведено математичне моделювання процесів зношування деталей та вузлів транспортних засобів. Досліджено процеси, які відбуваються в контакті "струмоприймач-контактний провід" та доведено можливість застосування перспективного контактного проводу в контактній мережі міського електротранспорту. Розроблено конструкцію пристрою для фізичного моделювання основних параметрів струмознімання для випробування контактних проводів і струмоприймачів різних конструкцій.Thesis for granting the Degree of Candidate of Technical sciences in speciality 05.22.09 - Electrical Transport. - National Technical University "Kharkiv Politechnical Institute", Kharkiv, 2015. The dissertation is devoted to solving actual scientific and practical task – development of resource-saving technologies rational of current collection by a city electric vehicle through the use of alternative materials and improved construction of a contact wire. Mathematical modeling of the wear of the parts and components of vehicles. The processes that occur in contact "pantograph-contact wire" and proved the possibility of application promising contact wires of the contact network of city electric transport. Developed the design of the device for physical modeling of main parameters of current collection for testing contact wires and current collectors of different designs.
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Скуріхін, Владислав Ігорович. "Розвиток ресурсозберігаючих технологій раціонального струмознімання на міському електротранспорті." Thesis, Харківський національний університет міського господарства ім. О. М. Бекетова, 2016. http://repository.kpi.kharkov.ua/handle/KhPI-Press/19875.
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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.22.09 – електротранспорт; Національний технічний університет "Харківський політехнічний інститут", Харків, 2015 р.
Дисертаційна робота присвячена вирішенню актуальної науково-практичної задачі – розвитку ресурсозберігаючих технологій раціонального струмознімання на міському електротранспорті за рахунок застосування в системі струмознімання альтернативних матеріалів і удосконаленої конструкції сталеалюмінієвого контактного проводу. Проведено математичне моделювання процесів зношування деталей та вузлів транспортних засобів. Досліджено процеси, які відбуваються в контакті "струмоприймач-контактний провід" та доведено можливість застосування перспективного контактного проводу в контактній мережі міського електротранспорту. Розроблено конструкцію пристрою для фізичного моделювання основних параметрів струмознімання для випробування контактних проводів і струмоприймачів різних конструкцій.Thesis for granting the Degree of Candidate of Technical sciences in speciality 05.22.09 - Electrical Transport. - National Technical University "Kharkiv Politechnical Institute", Kharkiv, 2015. The dissertation is devoted to solving actual scientific and practical task – development of resource-saving technologies rational of current collection by a city electric vehicle through the use of alternative materials and improved construction of a contact wire. Mathematical modeling of the wear of the parts and components of vehicles. The processes that occur in contact "pantograph-contact wire" and proved the possibility of application promising contact wires of the contact network of city electric transport. Developed the design of the device for physical modeling of main parameters of current collection for testing contact wires and current collectors of different designs.
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Tyrrell, Simon. "Random and rational methods for compound selection." Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370002.
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Chen, Jie Ph D. Massachusetts Institute of Technology. "Computer-aided rational solvent selection for pharmaceutical crystallization." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/59874.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemical Engineering, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 131-135).
Solvents play an important role in crystallization, a commonly used separation and purification technique in the pharmaceutical, chemical and food industries. They affect crystal properties such as particle size distribution, morphology, polymorphism etc. and therefore have consequences for the downstream processing of the solid material. Current solvent selection techniques for solution crystallization remain ad hoc and typically do not have a theoretical underpinning. Elucidation of the interactions between solvent and solute molecules and the mechanism underlying the solvent effects on each aspect of the crystal properties would be a major aid for the rational selection of solvents and also the development of crystallization processes. In this work we studied the effect of solvent on the polymorphism and morphology of organic crystals using molecular modeling techniques. The two most important contributions of this thesis are listed below. 1. We studied the self-assembly of solute molecules in solutions prior to nucleation for two polymorphic systems, tetrolic acid and glycine, using molecular dynamics simulations. We tested the existence of a link between the structure of the clusters formed in solution and the polymorphism of the crystals. Our results show that the link hypothesis succeeds in explaining the polymorph selection of tetrolic acid from different solvents. However it fails for glycine and thus should be used with caution. 2. We designed a computer-aided rational solvent selection procedure for improving the morphology of needle-like 2,6-dihydroxybenzoic acid form 2 crystal. We also experimentally grew 2,6-dihydroxybenzoic acid form 2 crystals using the solvent mixture suggested by computer simulations, which do exhibit reduced aspect ratios. This computer-aided selection procedure can not only quickly identify an effective solvent or solvent mixture, but also provide mechanistic understandings of the underlying chemistry. It can also be extended to improve the morphology of other needle-like organic crystals easily.
by Jie Chen.
Ph.D.
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Meise, Monika. "Residual based selection of smoothing parameters." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=974404551.
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Illingworth, Joseph. "Rational selection of antigens for a blood-stage malaria vaccine." Thesis, University of Oxford, 2014. https://ora.ox.ac.uk/objects/uuid:1a5db093-46c8-4714-b575-25b74a524500.
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Guerreiro, A. "Rational analysis of physico-chemical parameters affecting recognition properties of molecularly imprinted polymers." Thesis, Cranfield University, 2006. http://dspace.lib.cranfield.ac.uk/handle/1826/11014.
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Molecularly imprinted polymers (MIPs) are new type of materials with tailor
made molecular
recognition sites. Despite their enormous potential in separations,
sensing and pharmaceutical industry, MIPs have so far failed to achieve significant
commercial
application. This is in part due to lack of understanding of MIPs at a
molecular level, strong binding site heterogeneity and poor compatibility with
aqueous solvents. This work is aimed at improving overall MIP performance and
quality, with special focus on the improvement of compatibility with aqueous
environment.
Compatibility with aqueous solvents was achieved by (i) employing a
molecular
modelling step prior to polynerisation, (ii) by studying the ionic properties
of the
polymer and (iii) by analysis of the influence of different polymerisation
conditions. The
study of the pressure and magnetic field effects on polymers allowed
us to
produce materials with increased stability, lower binding site heterogeneity and
higher affinity, as compared to standard imprinted materials. To minimise site
heterogeneity imprinted nanoparticles with ca. 90 kDa were produced using a living
polymerisation method. The particles with essentially uniform population of binding
sites were obtained
by employing affinity chromatography with immobilised
template. As a model system variety of drugs were imprinted with the polymers being
able to discriminate between
closely related structural analogues in aqueous media.
This work had substantial effect on success of project Pisarro - Piezoelectric
Sensing Arrays for Biomolecular Interactions and Gas Monitoring where range of
imprinted polymers were designed with high affinity to drugs of abuse. Currently
1
work is in
progress aimed at application of these materials in commercial sensors for
forensic use.
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Guerreiro, António. "Rational analysis of physico-chemical parameters affecting recognition properties of molecularly imprinted polymers." Thesis, Cranfield University, 2006. http://dspace.lib.cranfield.ac.uk/handle/1826/11014.
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Molecularly imprinted polymers (MIPs) are new type of materials with tailor made molecular recognition sites. Despite their enormous potential in separations, sensing and pharmaceutical industry, MIPs have so far failed to achieve significant commercial application. This is in part due to lack of understanding of MIPs at a molecular level, strong binding site heterogeneity and poor compatibility with aqueous solvents. This work is aimed at improving overall MIP performance and quality, with special focus on the improvement of compatibility with aqueous environment. Compatibility with aqueous solvents was achieved by (i) employing a molecular modelling step prior to polynerisation, (ii) by studying the ionic properties of the polymer and (iii) by analysis of the influence of different polymerisation conditions. The study of the pressure and magnetic field effects on polymers allowed us to produce materials with increased stability, lower binding site heterogeneity and higher affinity, as compared to standard imprinted materials. To minimise site heterogeneity imprinted nanoparticles with ca. 90 kDa were produced using a living polymerisation method. The particles with essentially uniform population of binding sites were obtained by employing affinity chromatography with immobilised template. As a model system variety of drugs were imprinted with the polymers being able to discriminate between closely related structural analogues in aqueous media. This work had substantial effect on success of project Pisarro - Piezoelectric Sensing Arrays for Biomolecular Interactions and Gas Monitoring where range of imprinted polymers were designed with high affinity to drugs of abuse. Currently 1 work is in progress aimed at application of these materials in commercial sensors for forensic use.
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Häggström, Jenny. "Selection of smoothing parameters with application in causal inference." Doctoral thesis, Umeå universitet, Statistiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-39614.
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This thesis is a contribution to the research area concerned with selection of smoothing parameters in the framework of nonparametric and semiparametric regression. Selection of smoothing parameters is one of the most important issues in this framework and the choice can heavily influence subsequent results. A nonparametric or semiparametric approach is often desirable when large datasets are available since this allow us to make fewer and weaker assumptions as opposed to what is needed in a parametric approach. In the first paper we consider smoothing parameter selection in nonparametric regression when the purpose is to accurately predict future or unobserved data. We study the use of accumulated prediction errors and make comparisons to leave-one-out cross-validation which is widely used by practitioners. In the second paper a general semiparametric additive model is considered and the focus is on selection of smoothing parameters when optimal estimation of some specific parameter is of interest. We introduce a double smoothing estimator of a mean squared error and propose to select smoothing parameters by minimizing this estimator. Our approach is compared with existing methods.The third paper is concerned with the selection of smoothing parameters optimal for estimating average treatment effects defined within the potential outcome framework. For this estimation problem we propose double smoothing methods similar to the method proposed in the second paper. Theoretical properties of the proposed methods are derived and comparisons with existing methods are made by simulations.In the last paper we apply our results from the third paper by using a double smoothing method for selecting smoothing parameters when estimating average treatment effects on the treated. We estimate the effect on BMI of divorcing in middle age. Rich data on socioeconomic conditions, health and lifestyle from Swedish longitudinal registers is used.
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Gurnon, Daniel G. "Uncovering structural determinants of coiled coils by rational design and in vivo selection." [Bloomington, Ind.] : Indiana University, 2005. http://wwwlib.umi.com/dissertations/fullcit/3185395.
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Thesis (Ph. D.)--Indiana University, 2005.Source: Dissertation Abstracts International, Volume: 66-08, Section: B, page: 4204. Adviser: Martha G. Oakley. Title from dissertation home page (viewed Oct. 10, 2006).
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吳焯基 and Cheuk-key Allen Ng. "Multiple comparison and selection of location parameters of exponential populations." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1990. http://hub.hku.hk/bib/B31231949.
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Ng, Cheuk-key Allen. "Multiple comparison and selection of location parameters of exponential populations /." [Hong Kong] : University of Hong Kong, 1990. http://sunzi.lib.hku.hk/hkuto/record.jsp?B12792421.
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Östlund, Rasmus. "PoGO+ Detector Cell Characterisation and Optimisation of Waveform Selection Parameters." Thesis, KTH, Fysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-192842.
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Alahmadi, Mohammed. "A Recursive Approach for Adaptive Parameters Selection in AMultifunction Radar." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1448981863.
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Teixidor, Ezpeleta Daniel. "Contribution to laser milling process parameters selection for process planning operations." Doctoral thesis, Universitat de Girona, 2013. http://hdl.handle.net/10803/124506.
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Nontraditional manufacturing processes (NTM) appeared to answer the growing demands of market productivity. Needs of higher quality products in less time and new demands such as new exotic work materials, innovative geometric designs as well as much smaller dimensions justify laser processes insight. Laser machining is a NTM which presents several unique advantages in material processing that makes it suitable to solve these demands. However, laser machining is a complex process, because the type of laser, the combination of process parameters, the material and the configuration of the process among other variables, could affect the performance of the process. This thesis focuses on increasing knowledge about the laser milling, establishing relationships between the process parameters and the key process aspects (quality, dimensional accuracy and productivity)Els processos de mecanitzat no tradicionals van aparèixer per donar resposta a la creixent demana del mercat productiu. A la necessitat de productes d’alta qualitat en el menor temps possible s’hi afegeixen noves demandes com nous materials exòtics, dissenys amb geometries innovadores així com dimensions molt petites. El mecanitzat làser és un procés no tradicional que presenta un seguit d’avantatges únics que el fan adequat per donar solució a aquestes demandes. Tot i això, el mecanitzat làser és un procés complex. El tipus de làser, la combinació dels paràmetres de procés, el material i la configuració, entre d’altres variables, poden afectar l’execució del procés. Aquesta tesi pretén ampliar el coneixement sobre el fresat làser, establint relacions entre els paràmetres de procés i els aspectes rellevants de procés (qualitat, precisió dimensional i productivitat)
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Vázquez, Lepe Elisa. "Contribution to micro-milling process parameters selection for process planning operations." Doctoral thesis, Universitat de Girona, 2014. http://hdl.handle.net/10803/145377.
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The development of new products with micro-metric characteristics and complex geometries has been a manufacturing trend in different industrial sectors, particularly for electronic, military, biomedical and aerospace industries. Manufacturing technologies such as electro discharge machining (EDM), laser beam machining (LBM), lithography machining (LM), and ultrasonic machining (USM) are commonly processes used to produce small pieces. Nonetheless, there are economical and technological barriers that reduce their feasibility for specific applications. Since CNC cutting machines and tools can achieve high levels of accuracy, micro-milling (milling downscaled process) represents a suitable technological process to manufacture micro-products. This thesis focuses on increasing knowledge about the micro-milling, establishing relationships between the process parameters as well as machining conditions and the key aspects of the final piece such as accuracy, quality surface finishing and geometrical qualityEl desarrollo de nuevos productos con características micro-métricas y geometrías complejas ha sido una tendencia en la manufactura en diferentes sectores industriales, particularmente para la industria electrónica, militar, biomédica y aeroespacial. Las tecnologías de producción como la electroerosión (EDM), mecanizado láser (LBM), mecanizado por litografía (LM) y mecanizado por ultrasonido (USM) son procesos comúnmente usados para producir piezas pequeñas. No obstante, existen barreras económicas y tecnológicas que reducen su factibilidad para aplicaciones específicas. Puesto que las máquinas-herramientas de corte CNC pueden lograr altos niveles de precisión; el micro-fresado (proceso escalado del fresado convencional) representa un proceso tecnológico adecuado para la fabricación de micro-productos. Esta tesis se centra en aumentar el conocimiento sobre el micro-fresado, estableciendo relaciones entre los parámetros del proceso, así como las condiciones de mecanizado y los aspectos clave de la pieza final pieza final como por ejemplo, la precisión, el acabado superficial de calidad y la calidad geométrica
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Acker, Frank. "Use of Entropy for Feature Selection with Intrusion Detection System Parameters." NSUWorks, 2015. http://nsuworks.nova.edu/gscis_etd/370.
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The metric of entropy provides a measure about the randomness of data and a measure of information gained by comparing different attributes. Intrusion detection systems can collect very large amounts of data, which are not necessarily manageable by manual means. Collected intrusion detection data often contains redundant, duplicate, and irrelevant entries, which makes analysis computationally intensive likely leading to unreliable results. Reducing the data to what is relevant and pertinent to the analysis requires the use of data mining techniques and statistics. Identifying patterns in the data is part of analysis for intrusion detections in which the patterns are categorized as normal or anomalous. Anomalous data needs to be further characterized to determine if representative attacks to the network are in progress. Often time subtleties in the data may be too muted to identify certain types of attacks. Many statistics including entropy are used in a number of analysis techniques for identifying attacks, but these analyzes can be improved upon. This research expands the use of Approximate entropy and Sample entropy for feature selection and attack analysis to identify specific types of subtle attacks to network systems. Through enhanced analysis techniques using entropy, the granularity of feature selection and attack identification is improved.
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Fleischmann, Marvin [Verfasser]. "Consumer Selection and Use of Software - Empirical Studies on Non-Rational Decision Making / Marvin Fleischmann." Berlin : epubli, 2016. http://d-nb.info/1122388578/34.
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Bhatia, Gaurav. "Estimating evolutionary parameters and detecting signals of natural selection from genetic data." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/90171.
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Thesis: Ph. D., Harvard-MIT Program in Health Sciences and Technology, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references.
Even prior to the elucidation of the structure of DNA, the theoretical foundations of population genetics had been well developed. Advances made by Sewall Wright, John B.S. Haldane, and Ronald A. Fisher form the basis with which we understand the statistical dynamics of evolution and inheritance. Using this foundation, recent advances in DNA profiling technologies have enabled genome-wide analysis of thousands of individuals from a diverse array of human populations. These new analyses can answer fundamental questions about human population differences, natural selection, and admixture. However, with this deluge of newly available data, confusion about statistical methods may lead to misleading conclusions about human population history and natural selection. We view it as imperative to put analyses of population differences on sound statistical footing. In the course of this thesis, we have developed methods and reanalyzed existing results in two related areas: the detection of natural selection and estimation of genetic distance. Throughout our work, we have strived for statistical rigor, attempting to understand variation in previously reported results and provide a resource for other researchers in our field. Where necessary, we have made simplifying assumptions about evolutionary processes but have attempted to state these clearly and validate their reasonableness using simulations. Our efforts have culminated in three projects that will be described in the subsequent chapters: (1) A model based approach to detect natural selection in 3 populations (2) A protocol to generate consistent estimates of FST and, (3) Reanalysis of previously reports of selection in African Americans since the arrival of their ancestors in the Americas. We note that our work is just part of a rich literature on population and evolutionary genetics. We have attempted to cite this literature in detail and have published our own methods to enable others to utilize and improve upon them.
by Gaurav Bhatia.
Ph. D.
20
Ferreira, Sandra S. "Improving the rational design of antifreeze glycoproteins through identification of the parameters that influence ice recrystallization inhibition." Thesis, University of Ottawa (Canada), 2009. http://hdl.handle.net/10393/28336.
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Antifreeze glycoproteins (AFGPs) are a subclass of biological antifreezes isolated from Antarctic and Atlantic Teleost fish. These compounds have the ability to depress the freezing points of solutions as well inhibit ice crystal growth, thereby protecting fish from cryoinjury and death. Although native AFGPs have considerable promise as cryoprotectants, their limited bioavailability, cytotoxicity, biological instability and lengthy chemical syntheses have precluded their Widespread use. Consequently, Ben et al. have designed non-cytotoxic stable C-linked AFGPs with comparable ice recrystalization inhibition (RI) to that of the natural compounds. This work also revealed that amongst glycopeptides with the same amino acid backbone, the overall recrystalization inhibition activity correlates to the hydration of the carbohydrate moiety. This interesting relationship lead to question if whether the hydration values of carbohydrates could be used to predict the activity of synthetic antifreeze glycoproteins. If true, it would greatly improve the rational design of synthetic analogues. Therefore the relationship between hydration and ice recrystalization inhibition was studied using small molecule carbohydrates. These results were also compared to the current standard in cryoprotection of tissues and cells, dimethyl sulfoxide, and C-linked carbohydrate derivatives. The study elucidates that there is a more accurate parameter then hydration to predict the ice recrystalization inhibition of carbohydrates, and it was defined as the Hydration Index .
Furthermore, the investigation of carbohydrates with respect to RI was extended to the disaccharide present in the native antifreeze glycoproteins, D-galactose-beta(1-3)-N-acetyl-galactosamine. Its vital importance in AFGPs is apparent as no synthetic AFGP (syAFGP) with a carbohydrate other then that found in the native disaccharide has been able to surpass the activity of the natural compounds. Yet the intrinsic properties of the disaccharide, separated from the peptide, have never been studied in terms of RI activity. Therefore, the synthesis of the native disaccharide and analysis of its RI activity would help to determine how much of a factor it is for the overall activity of the natural AFGP. This work also creates the opportunity to study how other aspects of D-galactose-beta(1-3)-N-acetyl-galactosamine effects ice recrystalization inhibition, such as the C2 N-acetyl moiety and the regiochemistry of the glycosidic linkage.
Another key component in improving the rational design of syAFGPs as cryoprotectants is to distinguish between the structural motifs necessary for ice recrystalization inhibition and thermal hysteresis. In 2004, Nishimura et al. published such work on the essential components of AFGPs for thermal hysteresis. They reported that even small changes to the native AFGPs can cause a loss of thermal hysteresis, for example exchanging the naturally occurring threonine residues for serine. Unfortunately, they did not test any of their compounds for recrystallization inhibition. Opportunely, the synthesis towards an antifreeze glycoprotein which contains serine residues in place of threonine residues is presented, with the future goal of testing for its RI activity.
The overall objective of this dissertation is to probe the characteristics that dictate antifreeze glycoprotein activity in terms of ice recrystalization inhibition, with the goal of providing useful information towards the rational design of potent non-toxic cryoprotectants.
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Hu, Qing. "Predictor Selection in Linear Regression: L1 regularization of a subset of parameters and Comparison of L1 regularization and stepwise selection." Link to electronic thesis, 2007. http://www.wpi.edu/Pubs/ETD/Available/etd-051107-154052/.
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Leeds, Timothy D. "Pork quality improvement estimates of genetic parameters and evaluation of novel selection criteria /." Columbus, Ohio : Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1133368574.
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Avalos, Raz Guzman Eduardo. "Estimation of genetic parameters and responses in selection for litter size in pigs." Thesis, University of Edinburgh, 1985. http://hdl.handle.net/1842/10680.
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Hashmi, Kashmeri. "Development of fuzzy logic based software for selection of turning and drilling parameters." Thesis, Liverpool John Moores University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.402945.
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Gu, Youping. "Estimates of genetic parameters and prediction of responses to selection in commercial pigs." Thesis, University of Edinburgh, 1988. http://hdl.handle.net/1842/12071.
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Hamza, Hamza Ali Adel. "Selection and justification the parameters of diesel power plant with heat recovery system." Thesis, NTU "KhPI", 2017. http://repository.kpi.kharkov.ua/handle/KhPI-Press/31664.
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Dissertation for the degree of candidate of technical sciences in specialty 05.05.03 – engines and power plants. – National Technical University "Kharkiv Polytechnic Institute". – Kharkiv, 2017. The dissertation is devoted to the choice and substantiation of parameters of a diesel power plant with heat recovery system of recycling the secondary heat from diesel engine using the Rankin cycle, which uses the heat of exhaust gases and cooling water systems. As a result of the analysis of the features of a promising power plant with a Hyundai 25/33 engine for the production of electric power at a plant in Iraq, a technological scheme of a comprehensive system for recycling diesel fuel from an electric power station with the additional generation of electricity, heat for heating heavy fuel, condensing technical water from exhaust gases. As a working fluid in the Rankin cycle, it is advisable to use the hot water from the engine cooling system. Using the developed mathematical model of the distillation circuit of the diesel power plant, the design-experimental study of the influence of the ambient temperature on the indicators of the efficiency of heat recovery was performed. When the ambient temperature changes from 0 ° C to 40 ° C, the amount of electric energy generated by the Rankin cycle for the Hyundai H25 / 33 engine increases to 10%. With a single cogeneration unit with a Hyundai H25 / 33 engine and a recycling complex developed, it is possible to get up to 2300 kg of water vapor condensate per day, which is very valuable in Iraq. Based on the results of the study, two variants of the technological scheme (projects A and B) were developed for the modernization of Hyundai diesel power plants. The feasibility study for the NPV method has shown that after the full recovery equipment is put into operation, the maximum achievable profit will be about 1 406 219 $ /year.Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.05.03 – двигуни та енергетичні установки. – Національний технічний університет "Харківський політехнічний інститут". – Харків, 2017. Дисертація присвячена вибору і обґрунтуванню параметрів дизель-електричної станції з системою утилізації вторинної теплоти дизеля з використанням циклу Ренкіна, що використовує теплоту відпрацьованих газів та системи охолодження. В результаті аналізу особливостей перспективної енергетичної установки з двигуном Hyundai 25/33 для виробництва електричної енергії на заводі в Іраку розроблена технологічна схема комплексної системи утилізації вторинної теплоти дизель-електричної станції з додатковим отриманням електроенергії, теплоти для підігріву важкого палива, конденсації технічної води з відпрацьованих газів двигуна. Для утилізації вторинної теплоти двигуна Hyundai H25/33 запропоновано утилізаційний контур установки, який працює за органічним циклом Ренкіна (ОЦР). В якості робочого тіла в циклі Ренкіна доцільно використовувати воду системи охолодження двигуна. З використанням розробленої математичної моделі утилізаційного контуру дизель-електростанції виконане розрахунково-експериментальне дослідження впливу температури навколишнього середовища на показники ефективності утилізаційного контуру. При зміні температури навколишнього середовища від 0 ° С до 40 ° С кількість електроенергії, виробленої за циклом Ренкіна для двигуна Hyundai H25/33 збільшується до 10%. При роботі однієї когенераційної установки з двигуном Hyundai H25/33 та розробленим утилізаційним комплексом можна отримати на добу до 2300 кг конденсату водяної пари, що є дуже цінною в Іраку. На основі результатів дослідження було розроблено два варіанта технологічної схеми (проекти "А" та "Б") модернізації дизельних електростанцій компанії Hyundai Heavy Industries. Виконана техніко-економічна оцінка проектів за метод NPV показала, що після того, як обладнання утилізаційного контуру в повному обсязі буде введено у експлуатацію, максимально досяжний прибуток складе близько 1 406 219 дол. США/рік.
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Gallant, Joseph P. "Natural selection and genetic variation in a promising Chagas disease drug target: Trypanosoma cruzi trans-sialidase." ScholarWorks @ UVM, 2017. http://scholarworks.uvm.edu/graddis/807.
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Rational drug design is a powerful method in which new and innovative therapeutics can be designed based on knowledge of the biological target aiming to provide more efficacious and responsible therapeutics. Understanding aspects of the targeted biological agent is important to optimize drug design and preemptively design to slow or avoid drug resistance. Chagas disease, an endemic disease for South and Central America and Mexico is caused by Trypanosoma cruzi, a protozoan parasite known to consist of six separate genetic clusters or DTUs (discrete typing units). Chagas disease therapeutics are problematic and a call for new therapeutics is widespread. Many researchers are working to use rational drug design for developing Chagas drugs and one potential target that receives a lot of attention is the T. cruzi trans-sialidase protein. Trans-sialidase is a nuclear gene that has been shown to be associated with virulence. In T. cruzi, trans-sialidase (TcTS) codes for a protein that catalyzes the transfer of sialic acid from a mammalian host coating the parasitic surface membrane to avoid immuno-detection. Variance in disease pathology depends somewhat on T. cruzi DTU, as well, there is considerable genetic variation within DTUs. However, the role of TcTS in pathology variance among and within DTU’s is not well understood despite numerous studies of TcTS. These previous studies include determining the crystalline structure of TcTS as well as the TS protein structure in other trypanosomes where the enzyme is often inactive. However, no study has examined the role of natural selection in genetic variation in TcTS. In order to understand the role of natural selection in TcTS DNA sequence and protein variation, we sequenced 540 bp of the TcTS gene from 48 insect vectors. Because all 48 sequences had multiple polymorphic bases, we examined cloned sequences from two of the insect vectors. The data are analyzed to understand the role of natural selection in shaping genetic variation in TcTS and interpreted in light of the possible role of TcTS as a drug target.
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Wu, Yier. "Optimal pose selection for the identification of geometric and elastostatic parameters of machining robots." Phd thesis, Ecole des Mines de Nantes, 2014. http://tel.archives-ouvertes.fr/tel-00983277.
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The thesis deals with the optimal pose selection for geometric and elastostatic calibration for industrial robots employed in machining of large parts. Particular attention is paid to the improvement of robot positioning accuracy after compensation of the geometric and elastostatic errors. To meet the industrial requirements of machining operations, a new approach for calibration experiments design for serial and quasi-serial industrial robots is proposed. This approach is based on a new industry-oriented performance measure that evaluates the quality of calibration experiment plan via the manipulator positioning accuracy after error compensation, and takes into account the particularities of prescribed manufacturing task by introducing manipulator test-poses. Contrary to previous works, the developed approach employs an enhanced partial pose measurement method, which uses only direct position measurements from an external device and allows us to avoid the non-homogeneity of relevant identification equations. In order to consider the impact of gravity compensator that creates closed-loop chains, the conventional stiffness model is extended by including in it some configuration dependent elastostatic parameters, which are assumed to be constant for strictly serial robots. Corresponding methodology for calibration of the gravity compensator models is also proposed. The advantages of the developed calibration techniques are validated via experimental study, which deals with geometric and elastostatic calibration of a KUKA KR-270 industrial robot.
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Pswarayi, Idah Zviripayi. "Genetic parameters and selection indices for a population of Pinus elliottii Engelm. var. elliottii." Thesis, University of Oxford, 1993. http://ora.ox.ac.uk/objects/uuid:97fc4675-4dae-4b43-a15e-d3e9f52f6948.
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P. elliottii Engelm. var. elliottii is an important exotic plantation species in Zimbabwe, where it is grown for saw-timber and resin production. Three progeny tests, originating from factorial matings between parents selected in plantations, were assessed at five, eight and 15 years. The objectives of the study were to characterise quantitative genetic variation in the population through the estimation of genetic parameters, and to use these parameters in combined indices to select for specified breeding objectives for P. elliottii in Zimbabwe. All traits of interest were under a reasonable degree of additive genetic control, and the magnitudes of nonadditive genetic variances were almost invariably much less than those of additive genetic variances. Narrow-sense heritabilities for growth traits, wood density and resin yield were moderate to high, ranging from 0.3 - 0.42; those for stem straightness and branching traits were lower, ranging between 0.10 and 0.25. Genetic correlations at each of the assessment ages were more variable; of most consequence for this study were the slight negative correlations between wood density and both stem diameter and volume, and the slight positive correlation between density and height. Age-age correlations for growth traits were high, indicating potential for early selection. Age-age correlations for other traits ranged from moderately negative to highly positive. Although statistically significant for many traits, genotype-environment interaction was judged by a number of criteria to be of little practical importance. No one site was the most efficient for selection across the range of traits for establishment at other sites; rather, a set of pooled parameters was estimated for application on sites typical of those on which commercial plantations of P. elliottii are established. Selection indices were constructed for four breeding objectives, representing differing assumptions about the relative importance of saw-timber and resin production. Indices for both direct and indirect selection were compared in terms of genetic gain, efficiency and accuracy, which were influenced by the differential weighting of traits in the breeding objective. The highest gains, efficiency and accuracies were for the breeding objective of saw-timber only; increasing the emphasis on resin production reduced each of these parameters, and also had a more adverse impact on wood density. For a breeding objective corresponding to or emphasizing saw-timber production, selection based on diameter or height at five years was best; selection on the latter has the advantage of maintaining wood density at around its present level. Should resin production also be important, resin yield or a correlated trait must be included in the index. Efficiencies of indirect selection were highest at five years, regardless of the breeding objective or selection criteria considered. The lack of economic information was a considerable hinderance in conducting these analyses. The construction of more complete indices, incorporating information from all siblings represented in the factorial mating design, was also investigated for the breeding objective of saw-timber production. These indices were compared in terms of gain and accuracy, and their effect on population structure in the subsequent generation. Selection based on the most complete index resulted in the greatest gain and accuracy, but also in the greatest reduction in additive genetic variance in the next generation. These results highlight the dilemma facing breeders charged both with achieving gains in the short term and maintaining diversity over the longer term. Breeding strategies which facilitate differential intensities of selection and breeding, and the maintenance of a large effective population size, are seen as the best means to resolve these conflicting demands; some implications for the breeding population of P. elliottii in Zimbabwe are discussed.
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Cooper, Jon Carl. "Efficient 𝐻₂-Based Parametric Model Reduction via Greedy Search." Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/101968.
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Dynamical systems are mathematical models of physical phenomena widely used throughout the world today. When a dynamical system is too large to effectively use, we turn to model reduction to obtain a smaller dynamical system that preserves the behavior of the original. In many cases these models depend on one or more parameters other than time, which leads to the field of parametric model reduction.
Constructing a parametric reduced-order model (ROM) is not an easy task, and for very large parametric systems it can be difficult to know how well a ROM models the original system, since this usually involves many computations with the full-order system, which is precisely what we want to avoid. Building off of efficient 𝐻-infinity approximations, we develop a greedy algorithm for efficiently modeling large-scale parametric dynamical systems in an 𝐻₂-sense.
We demonstrate the effectiveness of this greedy search on a fluid problem, a mechanics problem, and a thermal problem. We also investigate Bayesian optimization for solving the optimization subproblem, and end with extending this algorithm to work with MIMO systems.Master of Science
In the past century, mathematical modeling and simulation has become the third pillar of scientific discovery and understanding, alongside theory and experimentation. Mathematical models are used every day, and are essential to modern engineering problems. Some of these mathematical models depend on quantities other than just time, parameters such as the viscosity of a fluid or the strength of a spring. These models can sometimes become so large and complicated that it can take a very long time to run simulations with the models. In such a case, we use parametric model reduction to come up with a much smaller and faster model that behaves like the original model. But when these large models vary highly with the parameters, it can also become very expensive to reduce these models accurately. Algorithms already exist for quickly computing reduced-order models (ROMs) with respect to one measure of how "good" the ROM is. In this thesis we develop an algorithm for quickly computing the ROM with respect to a different measure - one that is more closely tied to how the models are simulated.
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Mazloumi, Gavgani Alireza. "Use Of Genetic Algorithm For Selection Of Regularization Parameters In Multiple Constraint Inverse Ecg Problem." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12612984/index.pdf.
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The main goal in inverse and forward problems of electrocardiography (ECG) is to better understand the electrical activity of the heart. In the forward problem of ECG, one obtains the body surface potential (BSP) distribution (i.e., the measurements) when the electrical sources in the heart are assumed to be known. The result is a mathematical model that relates the sources to the measurements. In the inverse problem of ECG, the unknown cardiac electrical sources are estimated from the BSP measurements and the mathematical model of the torso. Inverse problem of ECG is an ill-posed problem, and regularization should be applied in order to obtain a good solution. Tikhonov regularization is a well-known method, which introduces a trade-off between how well the solution fits the measurements and how well the constraints on the solution are satisfied. This trade-off is controlled by a regularization parameter, which can be easily calculated by the L-curve method. It is theoretically possible to include more than one constraint in the cost functionhowever finding more than one regularization parameter to use with each constraint is a challenging problem. It is the aim of this thesis to use genetic algorithm (GA) optimization method to obtain regularization parameters to solve the inverse ECG problem when multiple constraints are used for regularization. The results are presented when there are two spatial constraints, when there is one spatial, one temporal constraint, and when there are two spatial one temporal constraints
the performances of these three applications are compared to Tikhonov regularization results and to each other. As a conlcusion, it is possible to obtain correct regularization parameters using the GA method, and using more than one constraints yields improvements in the results.
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Sucic, Victor. "Parameters Selection for Optimising Time-Frequency Distributions and Measurements of Time-Frequency Characteristics of Nonstationary Signals." Queensland University of Technology, 2004. http://eprints.qut.edu.au/15834/.
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The quadratic class of time-frequency distributions (TFDs) forms a set of tools which allow to effectively extract important information from a nonstationary signal. To determine which TFD best represents the given signal, it is a common practice to visually compare different TFDs' time-frequency plots, and select as best the TFD with the most appealing plot. This visual comparison is not only subjective, but also difficult and unreliable especially when signal components are closely-spaced in the time-frequency plane. To objectively compare TFDs, a quantitative performance measure should be used. Several measures of concentration/complexity have been proposed in the literature. However, those measures by being derived with certain theoretical assumptions about TFDs are generally not suitable for the TFD selection problem encountered in practical applications. The non-existence of practically-valuable measures for TFDs' resolution comparison, and hence the non-existence of methodologies for the signal optimal TFD selection, has significantly limited the use of time-frequency tools in practice. In this thesis, by extending and complementing the concept of spectral resolution to the case of nonstationary signals, and by redefining the set of TFDs' properties desirable for practical applications, we define an objective measure to quantify the quality of TFDs. This local measure of TFDs' resolution performance combines all important signal time-varying parameters, along with TFDs' characteristics that influence their resolution. Methodologies for automatically selecting a TFD which best suits a given signal, including real-life signals, are also developed. The optimisation of the resolution performances of TFDs, by modifying their kernel filter parameters to enhance the TFDs' resolution capabilities, is an important prerequisite in satisfying any additional application-specific requirements by the TFDs. The resolution performance measure and the accompanying TFDs' comparison criteria allow to improve procedures for designing high-resolution quadratic TFDs for practical time-frequency analysis. The separable kernel TFDs, designed in this way, are shown to best resolve closely-spaced components for various classes of synthetic and real-life signals that we have analysed.
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Shrestha, Samir. "Sensitivity of Hazus-MH Flood Loss Estimates to Selection of Building Parameters: Two Illinois Case Studies." OpenSIUC, 2014. https://opensiuc.lib.siu.edu/theses/1565.
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In this study, Hazus-MH (v 2.1 SP 2) flood-loss estimation tools were assessed for their sensitivity to an array of different building and model parameters. The purpose of this study is to help guide users of the Hazus-MH flood-loss modeling tool in the selection of most appropriate model parameters. Six model parameters (square footage of the building, building age, construction types, foundation types, first floor heights, and the number of stories in the building) were assessed for their impacts on flood losses using the Hazus-MH user defined and aggregate flood-loss models. Building stock databases for these analyses were developed using county assessor records from two Illinois counties. A validation assessment was also performed using observed flood-damage survey data collected after the 2011 Mississippi River Flood which inundated the Olive Branch Area in Alexander County, Illinois. This analysis was performed to assess the accuracy of the detailed Hazus-MH User Defined Facility (UDF) flood-loss modeling tool. The foundation types and its associated first floor heights and number of stories in the building were found to substantially impact flood-loss estimates using the Hazus-MH flood-loss modeling tool. The model building parameters square footage, building age and construction type had little or no effect on the flood-loss estimates. The validation assessment reveled Hazus-MH UDF flood-loss modeling tool is capable of providing a reasonable estimate of actual flood losses. The validation assessment showed the modeled results to be within 23% of actual losses. The validation study results attained in this study using the detailed UDF flood-loss modeling tool where more realistic (within 23% of actual losses versus > 50% of actual losses) than previous Hazus-MH flood-loss validation assessments. The flood-loss estimates could be further improved by modifying or choosing a more region specific depth-damage curve, using higher resolution DEM and improving the flood-depth grid by incorporating more detailed flood elevation data or estimates using detailed hydraulic models that better reflects the local inundation conditions.
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Baseer, Mohammed Abdul. "Wind resource assessment and GIS-based site selection methodology for efficient wind power deployment." Thesis, University of Pretoria, 2017. http://hdl.handle.net/2263/61314.
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An enormous and urgent energy demand is predicted due to the growing global population, increase in power intensive industries, higher living standards, electrification of remote areas, and globalisation (transportation). Moreover, the global consciousness about the harmful effects of traditional methods of power generation on the environment. That, in turn, has created a need to strategically plan and develop renewable and sustainable energy generation systems. This study presents a wind resource assessment of seven locations proximate to the largest industrial hub in the Middle East, Jubail Industrial City, Kingdom of Saudi Arabia, and a Geographic Information System, GIS based model considering a multi-criteria wind farm site suitability approach for the entire Kingdom of Saudi Arabia and elsewhere.
The hourly mean wind speed data at 10, 50 and 90 m above the ground level (AGL) over a period of five years was used for a meteorological station at the Industrial Area (Central) of Jubail. At the remaining six sites, the meteorological data were recorded at 10 m AGL only. Five years of wind data were used for five sites and three years of data were available for the remaining one site. At the Industrial Area (East), the mean wind speeds were found to be 3.34, 4.79 and 5.35 m/s at 10, 50 and 90 m AGL, respectively. At 50 and 90 m AGL, the availability of wind speed above 3.5 m/s was more than 75%. The local wind shear exponent, calculated using measured wind speed values at three heights, was found to be 0.217. The mean wind power density values at measurement heights were 50.92, 116.03 and 168.46 W/m2, respectively. After the assessment and comparison of wind characteristics of all seven sites, the highest annual mean wind speed of 4.52 m/s was observed at Industrial Area (East) and the lowest of 2.52 m/s at the Pearl Beach with standard deviations of 2.52 and 1.1 m/s, respectively.
In general, at all sites, the highest monthly mean wind speed was observed in February/June and the lowest in September/October. The period of higher wind availability coincides with a high power demand period in the region attributable to the air conditioning load. The wind rose plots show that the prevailing wind direction for all sites was from the north-west. Weibull parameters for all sites were estimated using maximum likelihood, least-squares regression method (LSRM), and WAsP algorithm. In general, at all sites, the Weibull parameter, c, was the highest in the months of February/June and the lowest in the month of October. The most probable and maximum energy carrying wind speed was determined by all three methods. The highest value of most probable wind speed was found to be in the range of 3.2 m/s to 3.6 m/s at Industrial Area (East) and the highest value of maximum energy carrying wind speed was found to be in the range 8.6 m/s to 9.0 m/s at Industrial Area 2 (South) by three estimation methods. The correlation coefficient (R2), root mean square error (RMSE), mean bias error (MBE), and mean bias absolute error (MAE) showed that all three methods represent wind data at all sites accurately. However, the maximum likelihood method is slightly better than LSRM, followed by WAsP algorithm. The wind power output at all seven sites, from five commercially available wind turbines of rated power ranging from 1.8 to 3.3 MW, showed that Industrial Area (East) is most promising for wind farm development. At all sites, based on percentage plant capacity factor, PCF, the 1.8 MW wind turbine was found to be the most efficient. At Industrial Area (East), this wind turbine was found to have a maximum PCF of 41.8%, producing 6,589 MWh/year energy output. The second best wind turbine was 3 MW at all locations except the Al-Bahar Desalination Plant and Pearl Beach. At both of these locations, 3.3 MW was the next best option. The energy output from the 3 MW wind turbine at Industrial Area (East) was found to be 11,136 MWh/year with a PCF of 41.3%. The maximum duration of rated power output from all selected wind turbines was observed to be between 8 to 16.6% at Industrial Area 2 (South). The minimum duration of rated power output, less than 0.3% for all wind turbines, was observed at Pearl Beach. The maximum duration of zero power output of between 35 to 60% was also observed at Pearl Beach.Thesis (PhD)--University of Pretoria, 2017.
Mechanical and Aeronautical Engineering
PhD
Unrestricted
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Schenkel, Flávio Schramm. "Studies on effects of parental selection on estimation of genetic parameters and breeding values of metric traits." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ35812.pdf.
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Dixit, Vikas. "Grain-Boundary Parameters Controlled Allotriomorphic Phase Transformations in Beta-Processed Titanium Alloys." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1357240292.
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Paget, Mark Frederick. "Genetic evaluation models and strategies for potato variety selection." Thesis, University of Canterbury. Forestry, 2014. http://hdl.handle.net/10092/9953.
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A series of studies are presented on the genetic evaluation of cultivated potato (Solanum tuberosum L.) to improve the accuracy and efficiency of selection at various stages of a breeding programme. The central theme was the use of correlated data, such as relationship information and spatial and across-trial correlations, within a linear mixed modelling framework to enhance the evaluation of candidate genotypes and to improve the genetic response to selection. Analyses focused on several social and economically-important traits for the enhancement of the nutritional value, disease resistance and yield of potato tubers.
At the formative stages of a breeding scheme, devising a breeding strategy requires an improved understanding of the genetic control of target traits for selection. To guide a strategy that aims to enhance the micronutrient content of potato tubers (biofortification), univariate and multivariate Bayesian models were developed to estimate genetic parameters for micronutrient tuber content from a breeding population generated from crosses between Andean landrace cultivars. The importance of the additive genetic components and extent of the narrow-sense heritability estimates indicated that genotypic 'individual' recurrent selection based on empirical breeding values rather than family-based selection is likely to be the most effective strategy in this breeding population. The magnitude of genetic correlations also indicated that simultaneous increases in important tuber minerals, iron and zinc, could be achieved.
Optimising selection efficiency is an important ambition of plant breeding programmes. Reducing the level of candidate replication in field trials may, under certain circumstances, contribute to this aim. Empirical field data and computer simulations inferred that improved rates of genetic gain with p-rep (partially replicated) testing could be obtained compared with testing in fully replicated trials at the early selection stages, particularly when testing over two locations. P-rep testing was able to increase the intensity of selection and the distribution of candidate entries across locations to account for G×E effects was possible at an earlier stage than is currently practised. On the basis of these results, it was recommended that the full replication of trials (at the first opportunity, when enough planting material is available) at a single location in the early stages of selection should be replaced with the partial replication of selection candidates that are distributed over two locations.
Genetic evaluation aims to identify genotypes with high empirical breeding values (EBVs) for selection as parents. Using mixed models, spatial parameters to target greater control of localised field heterogeneity were estimated and variance models to account for across-trial genetic heterogeneity were tested for the evaluation of soil-borne powdery scab disease and tuber yield traits at the early stages of a selection programme. When spatial effects improved model fit, spatial correlations for rows and columns were mostly small for powdery scab, and often small and negative for marketable and total tuber yield suggesting the presence of interplot competition in some years for tuber yield traits. For the evaluation of powdery scab, genetic variance structures were tested using data from 12 years of long-term potato breeding METs (multi-environment trials). A simple homogeneous correlation model for the genetic effects was preferred over a more complex factor analytic (FA) model. Similarly, for the MET evaluation of tuber yield at the early stages, there was little benefit in using more complex FA models, with simple correlation structures generally the most favourable models fitted. The use of less complex models will be more straightforward for routine implementation of potato genetic evaluations in breeding programmes.
Evaluations for (marketable) tuber yield were extended to multi-location MET data to characterise both genotypes and environments, allowing a re-evaluation of New Zealand MET selection strategies aimed at broad adaptation. Using a factor analytic mixed model, results indicated that the programme’s two main trial locations in the North and the South Islands optimised differentiation between genotypes in terms of G×E effects. There was reasonable performance stability of genotypes across test locations and evidence was presented for some, but limited, genetic progress of cultivars and advanced clonal selections for tuber marketable yield in New Zealand over recent years.
The models and selection strategies investigated and developed in this thesis will allow an improved and more systematic application of genetic evaluations in potato selection schemes. This will provide the basis for well informed decisions to be made on selection candidates for the genetic improvement of potato in breeding programmes.
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Assenza, Fabrizio. "Modelling genetic selection for gastrointestinal parasites resistance in small ruminants." Thesis, Toulouse, INPT, 2014. http://www.theses.fr/2014INPT0074/document.
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Les nématodes gastro-intestinaux sont des parasites de la caillette des petits ruminants qui posent des contraintes majeures pour l’élevage de ces animaux dans le monde. Récemment leur impact économique a augmenté notamment à cause de l’apparition de nématodes résistants aux anthelminthiques. La sélection génétique pourrait être une stratégie complémentaire des traitements chimiques. Dans cette thèse, nous avons exploré la variabilité génétique disponible qui permettrait une sélection sur la résistance aux nématodes. Les résultats obtenus en termes d’héritabilités, corrélations génétiques et QTLs, suggèrent que la variation génétique des populations étudiées pourrait satisfaire les requis d’un objectif de sélection permettant à la fois d’améliorer la résistance aux nématodes et la croissance des animaux. En outre, l’identification de loci SNP associés à la variation observée sur les caractères de résistance aux nématodes pourrait nous permettre d’améliorer la réponse à la sélectionAbomasal nematodes are a major constraint to small ruminants industry worldwide. Recently their economic impact has increased due to the recrudescence of anthelmintic resistance among many parasite populations. Genetic selection might be a valid strategy for enhancing the efficacy of anthelmintics. We explored the genetic variability, in both sheep and goat, possibly available for a breeding plan featuring parasite resistance as its breeding goal. The results obtained in terms of heritabilities, genetic correlations and QTLs, suggest that the variation in the genetic pool of the population under study might comply with the requirements of a breeding goal including both parasite resistance and production traits. Furthermore, marker assisted selection could be a feasible option to enhance the selection response
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Jakubowski, Marek. "Influence of selection constructional parameters on swirling process in centrifagal - settling vat during the sedimentary solids clarification : PhD thesis summary." Rozprawa doktorska, [s.n.], 2008. http://dlibra.tu.koszalin.pl/Content/1105.
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Mashiloane, Majela Lesley. "Effect of selection at weaning on genetic parameters of weight gain for centralized and on farm test for beef bulls." Thesis, University of Limpopo (Turfloop Campus), 2007. http://hdl.handle.net/10386/788.
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Thesis (M.Sc.) (Agriculture) --University of Limpopo, 2007The objectives of this study were to evaluate the effect of pre-weaning selection on estimates of genetic parameters for post-weaning average daily gain in Phases C (ADG-C) and D (ADG-D) and to estimate genetic relationships between average daily gain in the two phases. Performance records of the South African Angus cattle breed was used in the analysis. (Co)variance components and genetic parameters for weaning (WWT), AGD-C and ADG-D were estimated by REML procedures fitting three different models (Models 1, 2 and 3) that differed in how they integrated sequential selection in the analysis of post-weaning traits. Model 1 was a univariate model of WWT, ADG-C and ADG-D. Model 2 was a two trait model of WWT and either ADG-C or ADG-D. Model 3 was a three trait model of WWT, ADG-C and ADG-D. Estimates of heritability for ADG-C were 0.39±0.08, 0.42±0.06 and 0.44±0.01 from Model 1, 2 and 3 respectively. Corresponding estimates of heritability for ADG-D were 0.18±0.021, 0.19±0.021 and 0.21±0.02 respectively. An estimate of genetic correlation between ADG-C and ADG-D was 0.58± and it suggested that the two traits may not necessarily be under the same genetic control. Rank correlations for all bulls based on ADG-C estimated breeding values (EBV’s) were 0.92, 0.83 and 0.94 for Model 1 vs. Model 2, Model 1 vs. Model 3 and Model 2 vs. Model 3 respectively. Corresponding ADG-D EBV’s rank correlations were 0.88, 0.84 and 0.93. Rank correlations for top and bottom 1%, 5% and 10% were lower than those for all bulls in both ADG-C and ADG-D. Low rank correlations showed that the difference in magnitude of genetic parameters from different models was enough to alter bull rankings based on EBV’s of ADG-C and ADG-D. Hence it was concluded that inclusion of pre-weaning information in genetic analysis for post-weaning average daily gain is necessary to account for selection at weaning.
the THRIP (Technology and Human Resource for Industry Project) and NRF (National Research Foundation).
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Văcar, Cornelia Paula. "Inversion for textured images : unsupervised myopic deconvolution, model selection, deconvolution-segmentation." Thesis, Bordeaux, 2014. http://www.theses.fr/2014BORD0131/document.
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Ce travail est dédié à la résolution de plusieurs problèmes de grand intérêt en traitement d’images : segmentation, choix de modèle et estimation de paramètres, pour le cas spécifique d’images texturées indirectement observées (convoluées et bruitées). Dans ce contexte, les contributions de cette thèse portent sur trois plans différents : modéle, méthode et algorithmique.Du point de vue modélisation de la texture, un nouveaumodèle non-gaussien est proposé. Ce modèle est défini dans le domaine de Fourier et consiste en un mélange de Gaussiennes avec une Densité Spectrale de Puissance paramétrique.Du point de vueméthodologique, la contribution est triple –troisméthodes Bayésiennes pour résoudre de manière :–optimale–non-supervisée–des problèmes inverses en imagerie dans le contexte d’images texturées ndirectement observées, problèmes pas abordés dans la littérature jusqu’à présent.Plus spécifiquement,1. la première méthode réalise la déconvolution myope non-supervisée et l’estimation des paramètres de la texture,2. la deuxième méthode est dédiée à la déconvolution non-supervisée, le choix de modèle et l’estimation des paramètres de la texture et, finalement,3. la troisième méthode déconvolue et segmente une image composée de plusieurs régions texturées, en estimant au même temps les hyperparamètres (niveau du signal et niveau du bruit) et les paramètres de chaque texture.La contribution sur le plan algorithmique est représentée par une nouvelle version rapide de l’algorithme Metropolis-Hastings. Cet algorithme est basé sur une loi de proposition directionnelle contenant le terme de la ”direction de Newton”. Ce terme permet une exploration rapide et efficace de l’espace des paramètres et, de ce fait, accélère la convergenceThis thesis is addressing a series of inverse problems of major importance in the fieldof image processing (image segmentation, model choice, parameter estimation, deconvolution)in the context of textured images. In all of the aforementioned problems theobservations are indirect, i.e., the textured images are affected by a blur and by noise. Thecontributions of this work belong to three main classes: modeling, methodological andalgorithmic. From the modeling standpoint, the contribution consists in the development of a newnon-Gaussian model for textures. The Fourier coefficients of the textured images are modeledby a Scale Mixture of Gaussians Random Field. The Power Spectral Density of thetexture has a parametric form, driven by a set of parameters that encode the texture characteristics.The methodological contribution is threefold and consists in solving three image processingproblems that have not been tackled so far in the context of indirect observationsof textured images. All the proposed methods are Bayesian and are based on the exploitingthe information encoded in the a posteriori law. The first method that is proposed is devotedto the myopic deconvolution of a textured image and the estimation of its parameters.The second method achieves joint model selection and model parameters estimation froman indirect observation of a textured image. Finally, the third method addresses the problemof joint deconvolution and segmentation of an image composed of several texturedregions, while estimating at the same time the parameters of each constituent texture.Last, but not least, the algorithmic contribution is represented by the development ofa new efficient version of the Metropolis Hastings algorithm, with a directional componentof the proposal function based on the”Newton direction” and the Fisher informationmatrix. This particular directional component allows for an efficient exploration of theparameter space and, consequently, increases the convergence speed of the algorithm.To summarize, this work presents a series of methods to solve three image processingproblems in the context of blurry and noisy textured images. Moreover, we present twoconnected contributions, one regarding the texture models andone meant to enhance theperformances of the samplers employed for all of the three methods
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Corvino, Tatiana Lucila Sobrinho [UNESP]. "Caracterização do consumo alimentar residual e relações com desempenho e características de carcaça de bovinos nelore." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/95320.
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Universidade Estadual Paulista (UNESP)
Objetivou-se com este trabalho avaliar desempenho, parâmetros de eficiência e correlações fenotípicas entre diferentes medidas de eficiência energética de animais Nelore selecionados para peso pós desmame e classificados quanto ao consumo alimentar residual (CAR). O CAR foi calculado pela diferença entre o consumo observado e o predito, baseado no PV0,75 e ganho médio diário (GMD), sendo os animais classificados como alto CAR (> 0,5 desvio padrão da média - menos eficientes), médio CAR (± 0,5 desvio padrão da média), e baixo CAR (< 0,5 desvio padrão da média - mais eficientes). Não foram observadas diferenças em PV inicial e final, GMD e consumo de matéria seca (CMS) entre as classes de CAR. Animais baixo CAR mostraram-se também foram melhores em eficiência alimentar, conversão alimentar e eficiência parcial de crescimento e não apresentaram diferenças em relação a taxa de crescimento relativo e taxa Kleiber. O CAR foi correlacionado à eficiência alimentar (-0,25), conversão alimentar (0,25), eficiência parcial de crescimento (-0,37) e CMS (0,16), não apresentou correlação significativa com PV (0,04), GMD (-0,02), taxa de crescimento relativo (-0,03) e taxa de Kleiber (-0,05). Foram encontradas correlações significativas entre conversão alimentar e PV inicial (0,34) e GMD (-0,46). A eficiência parcial de crescimento foi correlacionada a todos os outros parâmetros de eficiência analisados. O CAR, quando comparado às demais medidas de eficiência energética, apresenta grande potencial na eficiência produtiva, sem alterar crescimento e tamanho dos animais.
The objective of this study was to evaluate performance, efficiency parameters and phenotypic correlations between different measures of energetic efficiency in animals Nellore selected for post weaning weight, and classified for residual feed intake (RFI). RFI was calculated as the difference between observed and predicted feed intake based on LW0.75 and average daily gain (ADG). Animals were classified as high RFI (> 0.5 standard deviation - less efficient), medium RFI ( ± 0.5 standard deviation), and low RFI (<0.5 standard deviation - more efficient). There were no differences in initial and final BW, ADG and dry matter intake (DMI) between RFI levels. Low RFI animals also were better in feed efficiency, feed conversion and partial efficiency of growth and were not different of relative growth rate and Kleiber ratio. RFI was correlated with feed efficiency (-0.25), feed conversion (0.25), partial efficiency of growth (-0.37) and DMI (0.16), and was not significantly correlated with BW (0.04 ), ADG (-0.02), relative growth rate (-0.03) and Kleiber ratio (-0.05). Significant correlations between feed conversion and initial BW (0.34) and ADG (-0.46) were detected. Partial efficiency of growth was correlated to all the others efficiency parameters analyzed. RFI, when compared to other energy efficiency measures, has great potential in productive efficiency, without affecting growth and size of animals.
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Vicente, António Pedro Andrade. "Characterization and selection of the Lusitano horse breed." Doctoral thesis, Universidade de Lisboa. Faculdade de Medicina Veterinária, 2015. http://hdl.handle.net/10400.5/8646.
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Tese de Doutoramento em Ciências Veterinárias. Especialidade de Produção AnimalUm estudo aprofundado de caracterização genética e estratégias de seleção na raça equina Lusitana foi realizado para identificar os principais fatores que afetam a variabilidade genética desta população e fornecer informações para o delineamento de um programa de melhoramento genético sustentável. Foi analisada a informação genealógica registada entre 1824-2009, incluindo 53417 animais. O intervalo de gerações médio foi de 11.33±5.23 e 9.71±4.48 anos para garanhões e éguas, respetivamente. Os animais nascidos entre 2005 e 2009 tiveram um número médio de gerações conhecidas de 11.20±0.71 e consanguinidade média de 11.34±7.48%. O aumento anual da consanguinidade foi de 0.173±0.070, a que corresponde um tamanho efetivo da população de 28. O número efetivo de fundadores, ascendentes e coudelarias fundadoras foi de 27.5, 11.7 e 5.4, respetivamente. Estes resultados refletem uma forte ênfase em algumas linhas e indicam a necessidade de uma gestão cuidadosa da diversidade genética para o futuro. Foram utilizados modelos mistos para estimar parâmetros genéticos, efeitos fixos e predizer valores genéticos para características morfo-funcionais por análises uni e multivariadas. Os caracteres morfológicos incluídos foram as pontuações parciais atribuídas a mais de 18 mil animais na sua inscrição como reprodutores (classificação de cabeça/pescoço, espádua/garrote, peitoral/costado, dorso/rim, garupa, membros e conjunto de formas), para além da pontuação final (FS), altura ao garrote (HW) e andamentos (GA). Funcionalmente foram considerados os resultados das provas de ensino (WEDT) e maneabilidade (WEMT) em Equitação de Trabalho (WE, cerca de 1500 resultados em 200 cavalos), e Dressage (CD, cerca de 12000 resultados em 760 cavalos). Os efeitos fixos para a morfologia foram a coudelaria, ano, sexo, consanguinidade e idade. Para a funcionalidade foram a prova, nível de competição, sexo, consanguinidade e idade. A heritabilidade estimada (h2) para as pontuações morfológicas parciais variou entre 0.12 e 0.18, à exceção dos membros (0.07). Foi também de 0.18 para FS, 0.61 para HW e 0.17 para GA. Para a performance a h2 foi de 0.32 (WEDT e CD) e 0.18 (WEMT). As correlações genéticas entre os vários componentes parciais de morfologia foram positivas mas muito variáveis (0.08-0.77). As relações genéticas entre morfologia e funcionalidade foram favoráveis, indicando que a morfologia/andamentos podem ser usados como caracteres complementares na seleção para a WE ou CD. A depressão consanguínea foi de magnitude muito reduzida para todos os caracteres analisados. Os valores genéticos estimados para a morfologia e funcionalidade apresentam grande variabilidade, mostrando que a seleção pode ser eficaz, mas a tendência genética observada ao longo dos últimos anos foi moderadamente positiva. Compararam-se ainda duas fontes diferentes de informação (pedigrees vs microssatélites) enquanto indicadores da diversidade genética e estrutura populacional do cavalo Lusitano. Para além das genealogias completas, foram utilizados dados sobre 6 ou 8 microssatélites genotipados em cerca de 19 mil Lusitanos entre 1998-2007. A consanguinidade obtida via genealogias revelou-se melhor estimador da consanguinidade molecular do que o inverso, mas apresentou uma correlação modesta com a heterozigotia multilocus (6% da variabilidade explicada). As taxas de consanguinidade por geração estimadas pelos dois métodos foram semelhantes. As distâncias genéticas entre as principais coudelarias foram comparáveis (correlação entre distâncias genéticas FST de 0.82). Globalmente, os parâmetros calculados a partir de informação genealógica são melhores preditores dos indicadores moleculares. No entanto, ao nível da população, os parâmetros de diversidade genética estimados, tendências ao longo do tempo e subestrutura da população são muito semelhantes quando estimados pelo pedigree ou por marcadores microssatélites.
ABSTRACT - Characterization and selection of the Lusitano horse breed - An in-depth study of characterization and evaluation of selection strategies in the Lusitano horse breed was conducted to identify factors affecting the genetic variability of the breed and provide baseline information for the establishment of a sustainable genetic improvement program. Pedigree records collected in 53417 animals born from 1824 to 2009 were used. The mean generation interval was 11.33±5.23 and 9.71±4.48 years for sires and dams, respectively. For animals born between 2005 and 2009, the mean number of equivalent generations was 11.20±0.71 and the average inbreeding was 11.34±7.48%. The rate of inbreeding per year was 0.173±0.070, and the corresponding effective population size was about 28. The effective number of founders, ancestors and studs was 27.5, 11.7 and 5.4, respectively. These results reflect a strong emphasis placed on a few sire-families and raise concerns regarding the conservation of genetic diversity for the future. Mixed model procedures were used to estimate genetic parameters, fixed effects and genetic trends for morpho-functional traits in Lusitano horses by uni- and multivariate animal models. Morphological traits included were partial scores attributed to more than 18000 horses at the time of registration in the studbook and included the classification of head/neck, shoulder/withers, chest/thorax, back/loin, croup, legs and overall impression, plus a final score (FS) and a score for gaits (GA) and the measurement of height at withers (HW). For functionality, the traits considered were scores obtained in dressage (WEDT) and maneability (WEMT) trials of working equitation (WE, about 1500 records by 200 horses), and classical dressage (CD, about 12130 records by nearly 760 horses). Fixed effects considered in the analyses of morphology, GA and FS were stud, year, sex, inbreeding and age. For functionally traits, the fixed effects were event, level of competition, sex, inbreeding and age. Heritability (h2) estimates for all partial morphological scores ranged between 0.12 and 0.18, except for legs (0.07), and were 0.18 for FS, 0.61 for HW and 0.17 for GA. For performance, h2 was 0.32 for WEDT and CD and 0.18 for WEMT. The genetic correlations among partial components of morphology were positive but widely different (0.08 to 0.77). The favourable genetic relationships existing between morphology and performance indicate that morphology and gaits traits can be used to enhance selection response when the improvement of WE or CD is intended. The magnitude of inbreeding depression was small for all the traits analyzed. The estimated breeding values for morphology, gaits and WE presented a large variability, indicating that selection can be effective, but the genetic trend observed over the last few years was positive but moderate for all traits. The assessment of genetic diversity and population structure obtained by either pedigree data or microsatellite markers was compared. The same pedigree database was used and, in addition, data on either 6 or 8 microsatellite markers genotyped in more than 19000 horses, from 1998-2007. Genealogical inbreeding was a better predictor of molecular inbreeding than the opposite, but it had a modest correlation with multilocus heterozygosity (6% of its variability). Still, the rates of inbreeding per generation estimated by the two methods were very similar. Genetic distances among the major studs producing Lusitano horses were comparable when they were estimated from pedigree or molecular information, with a correlation between FST distances of 0.82, and similar dendrograms were obtained in both cases. Overall, estimates derived from a reduced number of microsatellites or from pedigrees are poorly correlated when considered at the individual level, but parameters derived from pedigree are better predictors of molecular-derived indicators. However, when considered at the breed-level, the estimated diversity parameters, time trends and population substructure are very similar when genealogical data or microsatellite markers are considered.
Instituto Politécnico de Santarém
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May, Michael. "Data analytics and methods for improved feature selection and matching." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/data-analytics-and-methods-for-improved-feature-selection-and-matching(965ded10-e3a0-4ed5-8145-2af7a8b5e35d).html.
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This work focuses on analysing and improving feature detection and matching. After creating an initial framework of study, four main areas of work are researched. These areas make up the main chapters within this thesis and focus on using the Scale Invariant Feature Transform (SIFT).The preliminary analysis of the SIFT investigates how this algorithm functions. Included is an analysis of the SIFT feature descriptor space and an investigation into the noise properties of the SIFT. It introduces a novel use of the a contrario methodology and shows the success of this method as a way of discriminating between images which are likely to contain corresponding regions from images which do not. Parameter analysis of the SIFT uses both parameter sweeps and genetic algorithms as an intelligent means of setting the SIFT parameters for different image types utilising a GPGPU implementation of SIFT. The results have demonstrated which parameters are more important when optimising the algorithm and the areas within the parameter space to focus on when tuning the values. A multi-exposure, High Dynamic Range (HDR), fusion features process has been developed where the SIFT image features are matched within high contrast scenes. Bracketed exposure images are analysed and features are extracted and combined from different images to create a set of features which describe a larger dynamic range. They are shown to reduce the effects of noise and artefacts that are introduced when extracting features from HDR images directly and have a superior image matching performance. The final area is the development of a novel, 3D-based, SIFT weighting technique which utilises the 3D data from a pair of stereo images to cluster and class matched SIFT features. Weightings are applied to the matches based on the 3D properties of the features and how they cluster in order to attempt to discriminate between correct and incorrect matches using the a contrario methodology. The results show that the technique provides a method for discriminating between correct and incorrect matches and that the a contrario methodology has potential for future investigation as a method for correct feature match prediction.
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Bothe, Alexandra [Verfasser]. "Plant parameters for the marker and trait assisted selection of drought stress tolerance in barley (Hordeum vulgare ssp. vulgare) / Alexandra Bothe." Bonn : Universitäts- und Landesbibliothek Bonn, 2015. http://d-nb.info/1080591699/34.
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Donaldson, Claire Louise. "Spine characteristics in sheep : metrology, relationship to meat yield and their genetic parameters." Thesis, University of Edinburgh, 2016. http://hdl.handle.net/1842/20381.
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The overall accuracy, efficiency and profitability of livestock improvement strategies can be greatly increased by incorporating quantitative genetics into livestock selection and breeding. Since the introduction of quantitative genetics, a range of traits describing the animal e.g. in terms of health, growth, fecundity, production, have been extensively evaluated in terms of genetics and are now commonly manipulated through breeding to achieve specific selection goals. An industry led enquiry as to the possibility of including spine traits in genetic selection to increase back length in sheep was the basis of the present thesis. Collecting information on spine traits (spine length, vertebrae length and vertebrae number) is of particular interest and use to the sheep breeding industry as there may be the potential to increase meat yield from the highly valuable longissimus thoracis et lumborum (LTL or loin), located parallel to the spine, with little associated change in production costs. The thesis focusses on the use of X-ray computed tomography (CT) scanning as a technique which would allow spine traits to be measured in vivo, hence being useful for genetic selection. The topogram scans produced from the CT scanning procedure were analysed to derive spine trait information for the thesis. The scans were from Scottish Blackface (maternal breed stock), Texel (terminal sire breed), Texel cross Mule and Poll Dorset cross Mule (three-way cross slaughter lambs) so as to represent the divergent genotypes found across the different levels of the United Kingdom’s (UK) three-tier crossbreeding structure of sheep. The present study explored as a first step intra- and inter-operator repeatability of assessment of spine traits from CT derived topograms, as a means to investigate the suitability of the approach for widespread uptake within industry where operators will vary. The results showed that there was high repeatability for intra- and inter-operator assessment of spine trait measurements verifying that the CT method could be accepted as a reliable alternative (to slaughter for example) to quantify spine traits. To determine whether spine traits are similar across the range of breeds representing the key genotypes and crosses in the UK sheep industry, numerous CT topograms were analysed. The results showed marked variation in spine traits within and between Scottish Blackface, Texel, Texel cross Mule and Poll Dorset cross Mule breeds and crosses. For example, the Texel breed was found to have the largest within-breed range for thoracolumbar vertebrae number (17 – 21; the majority possessing 19), but the spine length of these animals was, on average, significantly shorter than the other breed/cross groups. The present study concluded that the significant differences between the breeds and breed types for the particular spine traits were possibly indicative of a genetic control for these traits. Furthermore, investigation into the phenotypic correlations between spine and production traits revealed some directional associations which may prove beneficial for meat production. For example, Scottish Blackface lambs which had a longer length of a specific spine region had an associated decrease in the volume of carcass fat. Texel lambs which had a longer length of a specific spine region had a slightly larger loin muscle area, at a given weight. The present study also examined animals from a population of Texel lambs already heavily selected for increased muscling. The Texel muscling quantitative trait locus (TM-QTL), segregating in these animals and generally in the UK’s Texel sheep population, is expressed through a polar overdominance pattern of inheritance and its effect on the loin (localised muscle hypertrophy) is commonly utilised in the selection and breeding of Texel sheep to improve meat production. Examination of topograms from lambs bearing the whole range of TM-QTL genotypes showed little evidence to suggest that the change in loin shape/increased loin muscling, as a result of the TM-QTL and its inheritance, has led to any associated change in the underlying spine characteristics. This suggests that selection for increased muscling associated with the TM-QTL may be achieved independently of changes in the spine traits studied. The potential to breed for certain spine traits to increase vertebrae number and hence chops or loin yield can be enhanced by establishing the genetic parameters for the traits. The present study employed a collection of performance trait records from Texel lambs to provide the basis for genetic analysis. The results showed different levels of heritability for the different spine traits but also high standard errors. For example, heritability of vertebrae number was dependent on vertebra location: for thoracic vertebrae heritability was high (ℎ2 = 0.99; SE = 0.42), for lumbar vertebrae heritability was low (ℎ2 = 0.08; SE = 0.12), whereas in contrast, thoracolumbar vertebrae heritability was moderate (ℎ2 = 0.44; SE = 0.27). Phenotypic and genetic correlations between all combinations of traits were also obtained. Accurate predictions of the size and direction of response to selection can be achieved through such genetic analysis of traits. The more that is known of the genetic characteristics of traits and their genetic correlations with other economically important traits, the more efficiently it can be built into breeding programmes improving the overall performance of stock. The results of this study showed that providing spine measurements can contribute to the diversity of trait information available to breeders. The present study also suggests that there may be opportunities to select for increased spine length/vertebrae number which would benefit the sheep industry in terms of increased chop number/loin yield. Although more data are needed prior to implementation. Practical uptake of selection for spine traits would be enhanced due to the straightforward nature of the measurements and the high operator repeatability.
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Gaus, Eric. "Macroeconomic models with endogenous learning." Thesis, University of Oregon, 2010. http://hdl.handle.net/1794/10868.
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xi, 87 p. : ill. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.The behavior of the macroeconomy and monetary policy is heavily influenced by expectations. Recent research has explored how minor changes in expectation formation can change the stability properties of a model. One common way to alter expectation formation involves agents' use of econometrics to form forecasting equations. Agents update their forecasts based on new information that arises as the economy progresses through time. In this way agents "learn" about the economy. Previous learning literature mostly focuses on agents using a fixed data size or increasing the amount of data they use. My research explores how agents might endogenously change the amount of data they use to update their forecast equations. My first chapter explores how an established endogenous learning algorithm, proposed by Marcet and Nicolini, may influence monetary policy decisions. Under rational expectations (RE) determinacy serves as the main criterion for favoring a model or monetary policy rule. A determinant model need not result in stability under an alternative expectation formation process called learning. Researchers appeal to stability under learning as a criterion for monetary policy rule selection. This chapter provides a cautionary tale for policy makers and reinforces the importance of the role of expectations. Simulations appear stable for a prolonged interval of time but may suddenly deviate from the RE solution. This exotic behavior exhibits significantly higher volatility relative to RE yet over long simulations remains true to the RE equilibrium. In the second chapter I address the effectiveness of endogenous gain learning algorithms in the presence of occasional structural breaks. Marcet and Nicolini's algorithm relies on agents reacting to forecast errors. I propose an alternative, which relies on agents using statistical information. The third chapter uses standard macroeconomic data to find out whether a model that has non-rational expectations can outperform RE. I answer this question affirmatively and explore what learning means to the economy. In addition, I conduct a Monte Carlo exercise to investigate whether a simple learning model does, empirically, imbed an RE model. While theoretically a very small constant gain implies RE, empirically learning creates bias in coefficient estimates.
Committee in charge: George Evans, Co-Chairperson, Economics; Jeremy Piger, Co-Chairperson, Economics; Shankha Chakraborty, Member, Economics; Sergio Koreisha, Outside Member, Decision Sciences
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Saptari, Adi. "PC computer based algorithm for the selection of material handling equipment for a distribution warehouse based on least annual cost and operating parameters." Ohio : Ohio University, 1990. http://www.ohiolink.edu/etd/view.cgi?ohiou1183473503.
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Alamedine, Dima. "Selection of EHG parameter characteristics for the classification of uterine contractions." Thesis, Compiègne, 2015. http://www.theses.fr/2015COMP2201/document.
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Un des marqueurs biophysique le plus prometteur pour la détection des accouchements prématurés (AP) est l'activité électrique de l'utérus, enregistrée sur l’abdomen des femmes enceintes, l’électrohystérogramme (EHG). Plusieurs outils de traitement du signal (linéaires, non linéaires) ont déjà été utilisés pour l'analyse de l'excitabilité et de la propagation de l’EHG, afin de différencier les contractions de grossesse, qui sont inefficaces, des contractions efficaces d’accouchement, qui pourraient provoquer un AP. Dans ces études nombreuses, les paramètres sont calculés sur des bases de données de signaux différentes, obtenus avec des protocoles d'enregistrement différents. Il est donc difficile de comparer les résultats afin de choisir les «meilleurs» paramètres pour la détection de l’AP. En outre, ce grand nombre de paramètres augmente la complexité de calcul dans un but de diagnostic. Par conséquent, l'objectif principal de cette thèse est de tester, sur une population de femmes donnée, quels outils de traitement du signal EHG permettent une discrimination entre les deux types de contractions (grossesse/accouchement). Dans ce but plusieurs méthodes de sélection de paramètres sont testées afin de sélectionner les paramètres les plus discriminants. La première méthode, développée dans cette thèse, est basée sur la mesure de la distance entre les histogrammes des paramètres pour les différentes classes (grossesse et accouchement) en utilisant la méthode « Jeffrey divergence (JD)». Les autres sont des méthodes de fouille de données existantes issues de la littérature. Les EHG ont été enregistrés en utilisant un système multivoies posé sur l'abdomen de la femme enceinte, pour l'enregistrement simultané de 16 voies d'EHG. Une approche monovariée (caractérisation d’une seule voie) et bivariée (couplage entre deux voies) sont utilisées dans notre travail. Utiliser toutes les voies, analyse monovariée, ou toutes les combinaisons de voies, analyse bivariée, conduit à une grande dimension des paramètres. Par conséquent, un autre objectif de notre thèse est la sélection des voies, ou des combinaisons de voies, qui fournissent l'information la plus utile pour distinguer entre les contractions de grossesse et d’accouchement. Cette étape de sélection de voie est suivie par la sélection des paramètres, sur les voies ou les combinaisons de voies sélectionnées. De plus, nous avons développé cette approche en utilisant des signaux monopolaires et bipolaires.Les résultats de ce travail nous permettent de mettre en évidence, lors du traitement de l’EHG, les paramètres et les voies qui donnent la meilleure discrimination entre les contractions de grossesse et celles d’accouchement. Ces résultats pourront ensuite être utilisés pour la détection des menaces d’accouchement prématuréOne of the most promising biophysical markers of preterm labor is the electrical activity of the uterus, picked up on woman’s abdomen, the electrohysterogram (EHG). Several processing tools of the EHG signal (linear, nonlinear), allow the analysis of both excitability and propagation of the uterine electrical activity in order to differentiate between pregnancy contractions, which are ineffective, from labor effective contractions that might cause preterm birth. Therefore, on these multiple studies, the parameters being computed from different signal databases, obtained with different recording protocols, it is sometimes difficult to compare their results in order to choose the “best” parameter for preterm labor detection. Additionally, this large number of parameters increases the computational complexity for diagnostic purpose. Therefore, the main objective of this thesis is to select, among all the features of interest extracted from multiple studies, the most pertinent feature subsets in order to discriminate, on a given population, pregnancy and labor contractions. For this purpose, several methods for feature selection are tested. The first one, developed in this work, is based on the measurement of the Jeffrey divergence (JD) distance between the histograms of the parameters of the 2 classes, pregnancy and labor. The other are “Filter” and “Wrapper” Data Mining methods, extracted from the literature. In our work monovariate (in one given EHG channel) and bivariate analysis (propagation of EHG by measuring the coupling between channels) are used. The EHG signals are recorded using a multichannel system positioned on the woman’s abdomen for the simultaneous recording of 16 channels of EHG. Using all channels, for the monovariate, or all combinations of channels for the bivariate analysis, leads to a large dimension of parameters for each contraction. Therefore, another objective of our thesis is the selection of the best channels, for the monovariate, or best channel combinations, for the bivariate analysis, that provide the most useful information to discriminate between pregnancy and labor classes. This channel selection step is then followed by the feature selection for the channels or channel combinations selected. Additionally, we tested all our work using monopolar and bipolar signals.The results of this thesis permits us to evidence, when processing the EHG, which channels and features can be used with the best chance of success as inputs of a diagnosis system for discrimination between pregnancy and labor contractions. This could be further used for preterm labor diagnosis
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Huang, Changwu. "Kriging-assisted evolution strategy for optimization and application in material parameters identification." Thesis, Normandie, 2017. http://www.theses.fr/2017NORMIR05.
Full textAbstract:
Afin de réduire le coût de calcul pour des problèmes d'optimisation coûteuse, cette thèse a été consacrée à la Stratégie d'Evolution avec Adaptation de Matrice de Covariance assistée par modèle de Krigeage (KA-CMA-ES). Plusieurs algorithmes de KA-CMA-ES ont été développés et étudiés. Une application de ces algorithmes KA-CMA-ES développés est réalisée par l'identification des paramètres matériels avec un modèle constitutif d'endommagement élastoplastique. Les résultats expérimentaux démontrent que les algorithmes KA-CMA-ES développés sont plus efficaces que le CMA-ES standard. Ils justifient autant que le KA-CMA-ES couplé avec ARP-EI est le plus performant par rapport aux autres algorithmes étudiés dans ce travail. Les résultats obtenus par l'algorithme ARP-EI dans l'identification des paramètres matériels montrent que le modèle d'endommagement élastoplastique utilisé est suffisant pour décrire le comportement d'endommage plastique et ductile. Ils prouvent également que la KA-CMA-ES proposée améliore l'efficace de la CMA-ES. Par conséquent, le KA-CMA-ES est plus puissant et efficace que CMA-ES pour des problèmes d'optimisation coûteuseIn order to reduce the cost of solving expensive optimization problems, this thesis devoted to Kriging-Assisted Covariance Matrix Adaptation Evolution Strategy (KA-CMA-ES). Several algorithms of KA-CMA-ES were developed and a comprehensive investigation on KA-CMA-ES was performed. Then applications of the developed KA-CMA-ES algorithm were carried out in material parameter identification of an elastic-plastic damage constitutive model. The results of experimental studies demonstrated that the developed KA-CMA-ES algorithms generally are more efficient than the standard CMA-ES and that the KA-CMA-ES using ARP-EI has the best performance among all the investigated KA-CMA-ES algorithms in this work. The results of engineering applications of the algorithm ARP-EI in material parameter identification show that the presented elastic-plastic damage model is adequate to describe the plastic and ductile damage behavior and also prove that the proposed KA-CMA-ES algorithm apparently improve the efficiency of the standard CMA-ES. Therefore, the KA-CMA-ES is more powerful and efficient than CMA-ES for expensive optimization problems