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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Analýza nejvyššího a nejlepšího využití objektu v Hradci Králové na ulici Průmyslová / Analysis of the highest and best use of a building in Průmyslová street in Hradec Králové

Zatloukal, Lukáš January 2015 (has links)
The diploma thesis deals with the valuation method called Analysis of the Highest and Best Use (HABU). In the theoretical part are described and explained four basic hypotheses of which analysis consists of. These are legal permissibility, physical possibility, financial substantiation and maximum productivity. The practical part deals with specific variants, on which calculations are demonstrated as well as confirmation or refutation of hypotheses.
52

Modeling and Control of a PMSynRel Drive for a Plug-InHybrid Electric Vehicle

Zhao, Shuang January 2011 (has links)
This thesis presents two transient models for a prototype integrated charger for use in a plug-in hybrid-electrical vehicle application. The models can be useful in order to develop control algorithms for the system or to recommend improvements to the machine design. A flux map based method, obtaining input data from simulations using the finite element method (FEM) is used to model the grid synchronization process. The grid side voltage can then be predicted by incorporating spatial flux linkage harmonics. The model is implemented in Matlab/Simulink and compared to stand alone FEM simulations with good agreement. The charging process is modeled using an inductance based model also requiring FEM simulations as input data. Since the flux linkages in the grid and inverter side windings are dependent on each other, the presented transient model is linearized around a specific operating point. This model is also implemented in a Matlab/Simulink environment. Sensorless control of a PMSynRel drive is also studied in this thesis. Focus is put on operating limits due to magnetic saturation when operating at low speeds. The rotating and pulsating voltage vector injection methods for sensorless control are studied in detail. A technique to map the feasible sensorless control region is proposed which utilizes the resulting position error signal rather than data of differential inductances. This technique is implemented experimentally and compared to corresponding FEM simulations with good agreement. The impact of spatial inductance harmonics on the quality of the position estimates is also studied. A method to predict the maximum position estimation error due to the inductance harmonics is proposed based on simplified analytical models. A technique is presented and experimentally verified which can compensate for this effect by injecting a modified rotating voltage carrier. Lastly, the impact of saturation in the rotor structure on the initial magnet polarity detection is investigated. The experimental results, in good agreement with the corresponding FEM simulations, indicate that the impact of saturation in the magnet bridges of rotor is the dominant phenomenon at lower peak current magnitudes. / QC 20110928
53

Ekologiškų namų racionalaus varianto intelektinės sistemos kūrimas / Development of an Intelligent System for Rational Variant of Eco-friendly Houses

Verikas, Vaidas 01 July 2011 (has links)
Baigiamajame magistro darbe nagrinėjamos ekologiškos statybinės medžiagos, analizuojami namo dalių konstrukciniai variantai, statant namus iš šių medžiagų. Taip pat sudaroma kompiuterinė sistema, padedanti vartotojui išsirinkti racionaliausią ekologiškų medžiagų panaudojimo variantą. Darbą sudaro trys dalys. Pirmojoje dalyje apžvelgiama ekologiškų statybinių medžiagų samprata, pagrindiniai principai, aprašomas statybinių medžiagų gyvavimo ciklas, aptariama aplinkai nekenksmingų medžiagų situacija Europoje. Antrojoje dalyje plačiau aprašomos gamtai nekenksmingos statybinės medžiagos, galimi tokių medžiagų konstrukciniai variantai. Analizuojami sienų, stogo dangos, šilumos izoliacijos ir šildymo sistemos pritaikymo galimybės statant ekologišką namą. Trečiojoje dalyje nagrinėjamas praktinis ekologiško namo konstrukcijų pritaikymo modelis. Sudaroma alternatyvų ir kriterijų sistema, apibūdinanti nekenksmingo aplinkai namo konstrukcinius elementus. Panaudojant kiekybinius ir kokybinius kriterijus ir galimas medžiagų alternatyvas, atliekama daugiakriterė statybinių medžiagų ir jų konstrukcijų analizė, sudaroma kompiuterinė sistema. / Ecological and environmentally friendly building materials and constructional options, that are used to build houses, are considered in this master work. It also contains the computer system enabling the user to choose the most rational option of ecological materials. This master work consists of three parts: In the first part the concept of ecological building materials and main principles are described. It also contains information about the life cycle of building materials and the situation of environmentally friendly materials in Europe are discussed. The second part describes environmentally friendly building materials and possible structural variations of such materials. It analyzes walls, roof, heat insulation and possibilities of heating system in the ecological house. In the third part the practical model of the ecological house is considered. An alternative and criteria system that describes the environmentally friendly house constructional elements is created. Using quantitative, qualitative criteria and possible material alternatives multiple criteria analysis of building materials and their construction is performed. The computer system is also made.
54

Force-Feasible Workspace Analysis and Motor Mount Disturbance Compensation for Point-Mass Cable Robots

Riechel, Andrew T. 12 April 2004 (has links)
Cable-actuated manipulators (or 'cable robots') constitute a relatively new classification of robots which use motors, located at fixed remote locations, to manipulate an end-effector by extending or retracting cables. These manipulators possess a number of unique properties which make them proficient with tasks involving high payloads, large workspaces, and dangerous or contaminated environments. However, a number of challenges exist which have limited the mainstream emergence of cable robots. This thesis addresses two of the most important of these issues-- workspace analysis and disturbance compensation. Workspace issues are particularly important, as many large-scale applications require the end-effector to operate in regions of a particular shape, and to exert certain minimum forces throughout those regions. The 'Force-Feasible Workspace' represents the set of end-effector positions, for a given robot design, for which the robot can exert a set of required forces on its environment. This can be considered as the robot's 'usable' workspace, and an analysis of this workspace shape for point-mass cable robots is therefore presented to facilitate optimal cable robot design. Numerical simulation results are also presented to validate the analytical results, and to aid visualization of certain complex workspace shapes. Some cable robot applications may require mounting motors to moving bases (i.e. mobile robots) or other surfaces which are subject to disturbances (i.e. helicopters or crane arms). Such disturbances can propagate to the end-effector and cause undesired motion, so the rejection of motor mount disturbances is also of interest. This thesis presents a strategy for measuring these disturbances and compensating for them. General approaches and implementation issues are explored qualitatively with a simple one-degree-of-freedom prototype (including a strategy for mitigating accelerometer drift), and quantitative simulation results are presented as a proof of concept.
55

Volné algebraické struktury a jejich využití pro segmentaci digitálního obrazu / Free algebraic structures and their application for segmentation of a digital image

Čambalová, Kateřina January 2015 (has links)
The thesis covers methods for image segmentation. Fuzzy segmentation is based on the thresholding method. This is generalized to accept multiple criteria. The whole process is mathematically based on the free algebra theory. Free distributive lattice is created from poset of elements based on image properties and the lattice members are represented by terms used by the threshoding. Possible segmentation results compose the equivalence classes distribution. The thesis also contains description of resulting algorithms and methods for their optimization. Also the method of area subtracting is introduced.
56

The effects of international trade on human development: a comparative analysis of the Association of Southeast Asian Nations (ASEAN) and the Southern African Development Community (SADC)

Angeles, Joseph Gerard Bacani 01 1900 (has links)
This study analysed the effects of international trade on human development in two developing regions, the Association of Southeast Asian Nations (ASEAN) and the Southern African Development Community (SADC). The choice of comparing SADC and ASEAN is motivated by the many similarities between both regions half a century ago, and the stark divergence of their respective development pathways which has led to different development outcomes half a century later. Annual data from 2000 to 2018 and dynamic panel data econometric techniques were used in this study, controlling for individual country characteristics, endogeneity, serial correlation, heterocedasticity and interdependencies between the countries in each region. Two estimations were done in this study; sample wide estimations and country specific estimations. In the sample wide estimations the Generalised Method of Moments of Arellano and Bover (1995) with forward orthogonal deviations, and Feasible Generalised Least Squares of Parks (1967) and Kmenta (1986) were used, whilst Swamy’s Random Coefficients were used in the country specific estimations. Trade is measured using the current account balance as a percentage of GDP, whilst human development is captured by the United Nations’ Human Development Index (HDI). In the sample wide estimations, the study found that trade openness enhances human development for both SADC and ASEAN as measured by the Human Development Index (HDI). Gross fixed capital formation, economic growth and technological progress all had positive effects on human development in both regions. Unemployment had a counter intuitive positive effect on human development. This raises issues on the nature and quality of employment, including concerns on cheap production labour and vulnerable employment. The ASEAN region had a higher mean level of economic growth, a trade surplus and higher level of technological progress than SADC. This is consistent with the manufacturing focus of ASEAN, compared to the primary commodity exporting nature of SADC which had a trade deficit. However, in each region there were country specific differences in terms of what drives human development. The country specific disparities in drivers of human development have implications for the regional trade and development nexus. In particular, these disparities must be considered in the conceptualization and implementation of the SADC Industrialisation and Strategy Roadmap, and the most recent African Continental Free Trade Area. The policy implication is that such regional trade agreements should accommodate countries’ specific heterogeneity as the policy pathways will differ between countries. / Business Management / D. Phil. (Management Studies)
57

Can the Poor Have Their Say? Structural Incorporation of Low-Income Voices in Corporate Governance

Corbin, Brian Roland 05 August 2022 (has links)
No description available.
58

Using Data-Driven Feasible Region Approximations to Handle Nonlinear Constraints When Applying CMA-ES to the Initial Margin Optimization Problem / Datadriven approximation av tillåtet område för att hantera icke-linjära bivillkor när CMA-ES används för att optimera initial margin

Wallström, Karl January 2021 (has links)
The introduction of initial margin requirements for non-cleared OTC derivatives has made it possible to optimize initial margin when considering a network of trading participants. Applying CMA-ES, this thesis has explored a new method to handle the nonlinear constraints present in the initial margin optimization problem. The idea behind the method and the research question in this thesis are centered around leveraging data created during optimization. Specifically, by creating a linear approximation of the feasible region using support vector machines and in turn applying a repair strategy based on projection. The hypothesis was that by repairing solutions an increase in convergence speed should follow. In order to answer the research question, a reference method was at first created. Here CMA-ES along with feasibility rules was used, referred to as CMA-FS. The proposed method of optimization data leveraging (ODL) was then appended to CMA-FS, referred to as CMA-ODL. Both algorithms were then applied to a single initial margin optimization problem 100 times each with different random seeds used for sampling in the optimization algorithms. The results showed that CMA-ODL converged significantly faster than CMA-FS, without affecting final objective values significantly negatively. Convergence was measured in terms of iterations and not computational time. On average a 5% increase in convergence speed was achieved with CMA-ODL. No significant difference was found between CMA-FS and CMA-ODL in terms of the percentage of infeasible solutions generated. A reason behind the lack of a reduction in violations can be due to how ODL is implemented with the CMA-ES algorithm. Specifically, ODL will lead to a greater number of feasible solutions being available during recombination in CMA-ES. Although, due to the projection, the solutions after projection are not completely reflective of the actual parameters used for that generation. The projection should also bias the algorithm towards the boundary of the feasible region. Still, the performative difference in terms of convergence speed was significant. In conclusion, the proposed boundary constraint handling method increased performance, but it is not known whether the method has any major practical applicability, due to the restriction to only considering the number of iterations and not the computational time. / Införandet av initial margin för non-cleared OTC derivatives har gjort det möjligt att optimera initial margin när ett flertal marknadsdeltagare tas till hänsyn. Denna uppsats har applicerat CMA-ES och specifikt undersökt en ny metod för hantering av de icke-linjära bivillkoren som uppstår när initial margin optimeras. Idén bakom metoden och forskningsfrågan i rapporten bygger på att utnyttja data som generas vid optimering. Detta görs specifikt genom att den icke-linjära tillåtna regionen approximeras linjärt med support vector machines. Därefter används en reparationsstrategi bestående av projicering för att reparera otillåtna lösningar. Hypotesen i uppsatsen var att genom att reparera lösningar så skulle konvergenshastigheten öka. För att svara på forskningsfrågan så togs en referensmetod fram, där CMA-ES och feasibility rules användes för att hantera icke-linjära bivillkor. Denna version av CMA-ES kallades CMA-FS. Sedan integrerades den nya metoden med CMA-FS, denna version kallades för CMA-ODL. Därefter så applicerades båda algoritmer 100 gånger på ett initial margin optimeringsproblem, där olika seeds användes för generering av lösningar i algoritmerna. Resultaten visade att CMA-ODL konvergerade signifikant snabbare än CMA-FS utan att påverka optimeringsresultatet negativt. Med CMA-ODL så ökade konvergenshastigheten med ungefär 5%. Konvergens mättes genom antal iterationer och inte beräkningstid. Ingen signifikant skillnad mellan CMA-ODL och CMA-FS observerades när de jämfördes med avseende på mängden icke-tillåtna lösningar genererade. En anledning varför ingen skillnad observerades är hur den nya metoden var integrerad med CMA-ES algoritmen. Den tilltänkta metoden leder till att fler tillåtna lösningar är tillgängliga när CMA-ES ska bilda nästa generation men eftersom lösningar projiceras så kommer dom inte att reflektera dom parametrar som användes för att faktiskt generera dom. Projiceringen leder också till att fler lösningar på randen av det tillåtna området kommer att genereras. Sammanfattningsvis så observerades fortfarande en signifikant ökning i konvergenshastighet för CMA-ODL men det är oklart om algoritmen är praktiskt användbar p.g.a. restriktionen att enbart betrakta antalet iterationer och inte total beräkningstid.
59

Probabilistic Multidisciplinary Design Optimization on a high-pressure sandwich wall in a rocket engine application

Wahlström, Dennis January 2017 (has links)
A need to find better achievement has always been required in the space industrythrough time. Advanced technologies are provided to accomplish goals for humanityfor space explorer and space missions, to apprehend answers and widen knowledges. These are the goals of improvement, and in this thesis, is to strive and demandto understand and improve the mass of a space nozzle, utilized in an upperstage of space mission, with an expander cycle engine. The study is carried out by creating design of experiment using Latin HypercubeSampling (LHS) with a consideration to number of design and simulation expense.A surrogate model based optimization with Multidisciplinary Design Optimization(MDO) method for two different approaches, Analytical Target Cascading (ATC) and Multidisciplinary Feasible (MDF) are used for comparison and emend the conclusion. In the optimization, three different limitations are being investigated, designspace limit, industrial limit and industrial limit with tolerance. Optimized results have shown an incompatibility between two optimization approaches, ATC and MDF which are expected to be similar, but for the two limitations, design space limit and industrial limit appear to be less agreeable. The ATC formalist in this case dictates by the main objective, where the children/subproblems only focus to find a solution that satisfies the main objective and its constraint. For the MDF, the main objective function is described as a single function and solved subject to all the constraints. Furthermore, the problem is not divided into subproblems as in the ATC. Surrogate model based optimization, its solution influences by the accuracy ofthe model, and this is being investigated with another DoE. A DoE of the full factorial analysis is created and selected to study in a region near the optimal solution.In such region, the result has evidently shown to be quite accurate for almost allthe surrogate models, except for max temperature, damage and strain at the hottestregion, with the largest common impact on inner wall thickness of the space nozzle. Results of the new structure of the space nozzle have shown an improvement of mass by ≈ 50%, ≈ 15% and ≈ -4%, for the three different limitations, design spacelimit, industrial limit and industrial limit with tolerance, relative to a reference value,and ≈ 10%, ≈ 35% and ≈ 25% cheaper to manufacture accordingly to the defined producibility model.
60

Monitoramento dos efeitos ecológicos e socioeconômicos da comercialização de produtos florestais não madereiros / Monitoring the ecological and socioeconomic effects of the commercialization of non-timber forest products

Brites, Alice Dantas 13 October 2010 (has links)
A comercialização de produtos florestais não madeireiros (PFNMs) popularizou-se como atividade promotora do desenvolvimento socioeconômico de comunidades florestais com baixo impacto ambiental. Há evidências, contudo, de que a exploração possa produzir efeitos ecológicos e socioeconômicos negativos, sugerindo que é necessário monitorar tais iniciativas. A comercialização frequentemente ocorre em áreas remotas e em contextos de pobreza, como é o caso de muitas daquelas da Amazônia brasileira. Desta forma, é necessário que o monitoramento restrinja-se a avaliar os efeitos evidenciados como mais comuns em estudos anteriores. Este estudo revisa e sintetiza as evidências científicas dos efeitos da exploração de PFNMs sobre parâmetros ecológicos e socioeconômicos e, a partir daí, indica aqueles mais relevantes ao monitoramento. O estudo também levanta até que ponto o monitoramento é implementado no contexto da Amazônia brasileira e avalia quais os parâmetros importantes e viáveis de monitoramento neste caso específico. Para isso, foram realizadas revisões sistemáticas da literatura e a consulta a profissionais da área através do método Delphi. Os resultados indicam que efeitos ecológicos negativos são frequentes, principalmente quando se coletam folhas ou cascas. Alterações em órgãos ou processos fisiológicos e a taxa de sobrevivência dos espécimes explorados são parâmetros que devem ser monitorados, em particular quando se coletam frutos e partes vegetativas. Para todos os tipos de PFNMs, o tamanho e a estrutura populacional são parâmetros prioritários ao monitoramento. A riqueza de espécies da comunidade explorada merece atenção, principalmente quando se coletam frutos. Para os aspectos socioeconômicos, efeitos positivos foram mais frequentes que negativos. A contribuição da renda monetária obtida com o comércio na renda total, a regularidade de ingresso desta renda e o papel dos PFNMs como recursos de salvaguarda são parâmetros do capital financeiro prioritários ao monitoramento. Para o capital social, o empoderamento feminino, a coesão de grupo e o acesso aos benefícios gerados pela comercialização devem ser monitorados. Na Amazônia brasileira são poucas as iniciativas de implementação do monitoramento da comercialização de PFNMs. Embora este seja considerado importante, existem dificuldades que derivam principalmente da falta de apoio institucional, políticas de incentivo e de recursos financeiros. Os profissionais participantes do Delphi consideram que os parâmetros ecológicos mais importantes a monitorar neste contexto são o tamanho e a estrutura populacional do recurso explorado, o aumento da taxa de mortalidade, a quantidade total de recurso extraída e a técnica de coleta utilizada. Para os parâmetros econômicos, aspectos do mercado, como o preço pago ao coletor, a demanda e a qualidade do produto, bem como a renda monetária obtida pelos indivíduos são os parâmetros considerados mais importantes. Por fim, para os aspectos sociais, os efeitos na cultura, na qualidade de vida e na organização interna da comunidade foram priorizados. Os profissionais indicam que é viável estabelecer o monitoramento dos parâmetros levantados. / Amazon, non-timber forest products, ecological effects, socioeconomic effects, monitoring.

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