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Scanlon, Eileen. „Modelling physics problem solving“. Thesis, Open University, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277276.
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Terry, Elaine Audrey. „Problem solving methods in game theory“. DigitalCommons@Robert W. Woodruff Library, Atlanta University Center, 1988. http://digitalcommons.auctr.edu/dissertations/1796.
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Game theory is the mathematical theory associated with winning strategic and non-strategic games. In order to win a game, a player must find an optimal strategy to play. Strategies may be either pure or mixed. The latter is used when there are no pure strategies available . Games that require mixed strategies may be solved by various methods.
This study is concerned with the basic theory of games. Definitions and methods for solving games are discussed. The methods for solving involve both pure and mixed strategies. The simplex method for solving linear programming problems is reviewed. The numerical examples were solved using the IBM Macintosh with the MacSimplex package.
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Santos, Trigo Luz Manuel. „College students' methods for solving mathematical problems as a result of instruction based on problem solving“. Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/31100.
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This study investigates the effects of implementing mathematical problem solving instruction in a regular calculus course taught at the college level. Principles associated with this research are: i) mathematics is developed as a response to finding solutions to mathematical problems, ii) attention to the processes involved in solving mathematical problems helps students understand and develop mathematics, and iii) mathematics is learned in an active environment which involves the use of guesses, conjectures, examples, counterexamples, and cognitive and metacognitive strategies. Classroom activities included use of nonroutine problems, small group discussions, and cognitive and metacognitive strategies during instruction.
Prior to the main study, in an extensive pilot study the means for gathering data were developed, including a student questionnaire, several assignments, two written tests, student task-based interviews, an interview with the instructor, and class observations.
The analysis in the study utilized ideas from Schoenfeld (1985) in which categories, such as mathematical resources, cognitive and metacognitive strategies, and belief systems, are considered useful in analyzing the students' processes for solving problems. A model proposed by Perkins and Simmons (1988) involving four frames of knowledge (content, problem solving, epistemic, and inquiry) is used to analyze students' difficulties in learning mathematics.
Results show that the students recognized the importance of reflecting on the processes involved while solving mathematical problems. There are indications suggesting that the students showed a disposition to participate in discussions that involve nonroutine mathematical problems. The students' work in the assignments reflected increasing awareness of the use of problem solving strategies as the course developed. Analysis of the students' task-based interviews suggests that the students' first attempts to solve a problem involved identifying familiar terms in the problem and making some calculations often without having a clear understanding of the problem. The lack of success led the students to reexamine the statement of the problem more carefully and seek more organized approaches. The students often spent much time exploring only one strategy and experienced difficulties in using alternatives. However, hints from the interviewer (including
metacognitive questions) helped the students to consider other possibilities. Although the students recognized that it was important to check the solution of a problem, they mainly focused on whether there was an error in their calculations rather than reflecting on the sense of the solution. These results lead to the conclusion that it takes time for students to conceptualize problem solving strategies and use them on their own when asked to solve mathematical problems.
The instructor planned to implement various learning activities in which the content could be introduced via problem solving. These activities required the students to participate and to spend significant time working on problems. Some students were initially reluctant to spend extra time reflecting on the problems and were more interested in receiving rules that they could use in examinations. Furthermore, student expectations, evaluation policies, and curriculum rigidity limited the implementation. Therefore, it is necessary to overcome some of the students' conceptualizations of what learning mathematics entails and to propose alternatives for the evaluation of their work that are more consistent with problem solving instruction.
It is recommended that problem solving instruction include the participation or coordinated involvement of all course instructors, as the selection of problems for class discussions and for assignments is a task requiring time and discussion with colleagues. Periodic discussions of course directions are necessary to make and evaluate decisions that best fit the development of the course.Education, Faculty of
Curriculum and Pedagogy (EDCP), Department of
Graduate
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Gábor, Richard. „Project Management and Problem Solving Methods in Management Consulting“. Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-71931.
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Conducting management consulting project for Transparency International Czech Republic, the leading non-profit non-governmental organization active in anti-corruption practices, by applying selected project management and problem solving methods, the objective of the thesis is to support the assumption that proper selection and application of suitable methods to problem identification, definition and decomposition enables to come up with the solution of the problem by analyzing it with no need for further solution development.
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Hamm, Jolene Diane. „Exploring the Dimensions of Problem-solving Ability on High-achieving Secondary Students: A Mixed Methods Study“. Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/40265.
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This mixed-methods study investigated the relationship between self-concept and problem-solving style and how these two constructs compared and contrasted in regards to a participantâ s perception of his or her problem-solving ability. The 86 study participants were high-achieving rising 11th and 12th grade students attending a summer enrichment program for agriculture. This study used a concurrent triangulation mixed methods design. The quantitative aspect of the study employed two instruments, SDQ III to test perceived self-concept and the VIEW to determine the perceived problem-solving style. Concurrent with this data collection, 13 open-ended interviews were conducted to explored the description of the problem-solving process during a problem-solving event. The reason for collection of both quantitative and qualitative data was to bring together the strengths of both forms of research in order to merge the data to make comparisons and further the understanding of problem-solving ability of high-achieving youth.
The study discovered that self-concept and problem-solving style have a weak relationship for many of the constructs and a negative relationship between two of constructs. The qualitative component revealed that high-achieving youth had clear definitions of problem-solving, a rich and descriptive heuristic approach, a clear understanding of which resources provided key information, and a strong depiction of themselves as problem-solver. An emergent concept from the research was the participantsâ perceptions of the team-based structure and how the inclusion of multiple ability levels versus high ability levels affected the participantsâ perceptions of solving a problem in a team situation. The mixing component of the study depicted the influence of self-concept on the problem-solving style.
This study was an initial exploration of the relationship between self-concept and problem-solving and compared the current results with previous research. It extended and connected the previous research areas of self-concept and problem-solving style. As an initial study, it led to recommendations for further research across education as well as additional exploration of the emergent relationships identified. Finally, the study denoted the importance of mixed-methods research due to the interconnectivity between self-concept and problem-solving style and the participant descriptions of themselves as problem-solvers.Ph. D.
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Ali, Ali Hasan. „Modifying Some Iterative Methods for Solving Quadratic Eigenvalue Problems“. Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1515029541712239.
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James, Alan John. „Solving the many electron problem with quantum Monte-Carlo methods“. Thesis, Imperial College London, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309224.
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Rajpathak, Dnyanesh. „A generic library of problem solving methods for scheduling applications“. Thesis, Open University, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.417488.
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Hilal, Mohammed Azeez. „Domain decomposition like methods for solving an electrocardiography inverse problem“. Thesis, Nantes, 2016. http://www.theses.fr/2016NANT4060.
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L’objectif de cette thèse est d’étudier un problème électrocardiographique (ECG), modélisant l’activité électrique cardiaque en utilisant un modèle bidomaine stationnaire. Deux types de modélisation sont considérées : la modélisation basée sur un modèle mathématique directe et la modélisation basée sur un problème inverse de Cauchy. Dans le premier cas, le problème directe est résolu en utilisant la méthode de décomposition de domaine et l’approximation par la méthode des éléments finis. Dans le deuxième cas le problème inverse de Cauchy de l’ECG a été reformulé en un problème de point fixe. Puis, un résultat d’existence et l’unicité du point fixe basé sur les degrés topologique de Leray-Schauder a été démontré. Ensuite, quelques algorithmes itératifs régularisant et stables basés sur les techniques de décomposition de domaine ont été développés. Enfin, l’efficacité et la précision des résultats obtenus a été discutésThe aim of the this thesis is to study an electrocardiography (ECG) problem, modeling the cardiac electrical activity by using the stationary bidomain model. Tow types of modeling are considered :The modeling based on direct mathematical model and the modeling based on an inverse Cauchy problem. In the first case, the direct problem is solved by using domain decomposition methods and the approximation by finite elements method. For the inverse Cauchy problem of ECG, it was reformulated into a fixed point problem. In the second case, the existence and uniqueness of fixed point based on the topological degree of Leray-Schauder is showed. Then, some regularizing and stable iterative algorithms based on the techniques of domain decomposition method was developed. Finally, the efficiency and the accurate of the obtained results was discussed
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Sycara, Ekaterini P. „Resolving adversarial conflicts : an approach integrating case-based and analytical methods“. Diss., Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/32955.
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Ege, Ozalkan Bilgen. „The Effects Of Problem Solving On The Topic Of Functions On Problem Solving Performance, Attitude Toward Problem Solving And Mathematics“. Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12611945/index.pdf.
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The purpose of the study was to investigate the effect of Problem Solving Method on 9th grade students‟
problem solving performance and attitudes toward mathematics and problem solving. This study was done in 2007-2008 academic year, in a private high school in Ankara. In the present study the experimental-control group pre-test post-test research design was used. The study was done with 67 students of the private high school. Experimental group was instructed with Problem Solving Method and control group was instructed with Traditional Method. The treatment was given for seven weeks, 21 lesson hours. Problem Solving Performance Test, Problem Solving Attitude Scale and Mathematics Attitude Scale were administered as a pre test and a post test. Independent samples t-test was used to examine the hypotheses of the present study. The results revealed that there were no statistically significant mean differences between experimental group and control group related to gained scores of understanding the problem, making a plan and carrying out the plan steps in Problem Solving Performance Test and Mathematics Attitude Scale. However, there was a statistically mean difference between these groups with respect to gained scores of Problem Solving Attitude Scale.
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Moody, Laura Ellen. „Supporting vehicle routing problem-solving using visualization and interactive optimization“. Diss., Georgia Institute of Technology, 1993. http://hdl.handle.net/1853/32776.
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Agerberg, Gösta. „Solving the Vehicle Routing Problem : using Search-based Methods and PDDL“. Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-202239.
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In this project the optimization of transport planning has been studied. The approach was that smaller transport companies do not have the capability to fully optimize their transports. Their transport optimization is performed at a company level, meaning that the end result might be optimal for their company, but that potential for further optimization exists. The idea was to build a collaboration of transport companies, and then to optimize the transports globally within the collaboration. The intent was for the collaboration to perform the same driving assignments but at a lower cost, by using fewer vehicles and drivers, or travel shorter distance, or both combined. This should be achieved by planning the assignments in a smarter way, for example using a company's empty return journey to perform an assignment for another company. Due to the complexity of these types of problems, called Vehicle Routing Problem (VRP), shown to be NP-complete, search methods are often used. In this project the method of choice was a PDDL-based planner called LPG-td. It uses enforced hill-climbing together with a best-first search to find feasible solutions. The method was tested for scaling, performance versus another method and against time, as well as together with a real-life based problem. The results showed that LPG-td might not be a suitable candidate to solve the problem considered in this project. The solutions found for the collaboration were worse than for the sum of individual solutions, and used more computational time. Since the solution for the collaboration at most should be equal to the sum of individual solutions, in theory, this meant that the planner failed.
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Mpinganzima, Lydie. „Iterative Methods for Solving the Cauchy Problem for the Helmholtz Equation“. Doctoral thesis, Linköpings universitet, Matematiska institutionen, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-105879.
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The inverse problem of reconstructing the acoustic, or electromagnetic, field from inexact measurements on a part of the boundary of a domain is important in applications, for instance for detecting the source of acoustic noise. The governing equation for the applications we consider is the Helmholtz equation. More precisely, in this thesis we study the case where Cauchy data is available on a part of the boundary and we seek to recover the solution in the whole domain. The problem is ill-posed in the sense that small errors in the Cauchy data may lead to large errors in the recovered solution. Thus special regularization methods that restore the stability with respect to measurements errors are used. In the thesis, we focus on iterative methods for solving the Cauchy problem. The methods are based on solving a sequence of well-posed boundary value problems. The specific choices for the boundary conditions used are selected in such a way that the sequence of solutions converges to the solution for the original Cauchy problem. For the iterative methods to converge, it is important that a certain bilinear form, associated with the boundary value problem, is positive definite. This is sometimes not the case for problems with a high wave number. The main focus of our research is to study certain modifications to the problem that restore positive definiteness to the associated bilinear form. First we add an artificial interior boundary inside the domain together with a jump condition that includes a parameter μ. We have shown by selecting an appropriate interior boundary and sufficiently large value for μ, we get a convergent iterative regularization method. We have proved the convergence of this method. This method converges slowly. We have therefore developed two conjugate gradient type methods and achieved much faster convergence. Finally, we have attempted to reduce the size of the computational domain by solving well–posed problems only in a strip between the outer and inner boundaries. We demonstrate that by alternating between Robin and Dirichlet conditions on the interior boundary, we can get a convergent iterative regularization method. Numerical experiments are used to illustrate the performance of the methods suggested.An invalid ISRN (LIU-TEK-LIC-2012:15) is stated on page 2. The ISRN belongs to the Licentiate thesis, published in 2012.
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Chiu, Mei-Shiu. „Children's emotional responses to mathematical problem-solving : the roles of teaching methods and problem types“. Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.597616.
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The aim of the thesis is to investigate children’s emotional responses to mathematical problem solving, based on the concern that children in Taiwanese mathematical classrooms are experiencing a significant change in teaching methods and problem types from the ‘traditional mathematics’ to ‘constructivist mathematics’. The focused emotional variables include disposition toward teaching, liberal thinking styles, conservative styles, deep approaches, surface approaches, self-efficacy of effort and mistake anxiety. The research participants were 116 Year 5 (aged 9-10) children and their respective four mathematics teachers. Fraction and coordinates topics were chosen as two focused topics, in which a number of typical ill- and well-structured problems were chosen as focused problems from the participants’ textbooks. There are three main research findings. First, teaching methods revealed impacts on children’s emotional response. Second, there were four distinct patterns of children’s emotional and motivational responses to mathematical problem solving, with differential development processes in terms of emotional variables and preferred problem types. Third, the best determinants of children’s attainments in mathematics were self-efficacy, thinking styles and learning approaches, which however varied with genders, teaching methods and problem types. Chapter 1 explains the background and situation of mathematics education in Taiwan and outlines the goals of the thesis. Chapter 2 is concerned with the literature on emotional issues in mathematical learning, teaching styles, problem types, genders and achievement in mathematics, based on which, the research questions are proposed. In Chapter 3, an initial model is posited in order to answer the research questions and develop a research design, involving both quantitative and qualitative research methods. Chapter 4 explores the impact of teaching methods on children’s emotional responses to mathematical problem solving by analysing data of systematic and narrative classroom observations, teacher interviews, child interviews and children’s responses to the questionnaires. Chapter 5 investigates factors and patterns of children’s emotional responses to mathematical problem solving by a factor analysis, cluster analysis, discriminant analysis and analysis of data from child interview with a repertory grid technique. Chapter 6 examines the determinants of mathematics attainments in terms of genders, teaching method and emotional responses to problem solving by ANOVAs and correlation analyses. Chapter 7 focuses on discussion and conclusions.
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Jain, Pramod. „APPROXIMATE METHODS FOR SOLVING FLOWSHOP PROBLEMS“. MSSTATE, 2005. http://sun.library.msstate.edu/ETD-db/theses/available/etd-11072005-155525/.
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The flow shop scheduling problem is a classical combinatorial problem being studied for years. The focus of this research is to study two variants of the flow shop scheduling problem in order to minimize makespan by scheduling n jobs on m machines. A solution approach is developed for the modified flow shop problem with due dates and release times. This algorithm is an attempt to contribute to the limited literature for the problem. Another tabu search-based solution approach is developed to solve the classical flow shop scheduling problem. This meta-heuristic (called 3XTS) allows an efficient search of the neighboring solutions leading to a fast solution procedure. Several control parameters affecting the quality of the algorithm are experimentally tested, and certain rules are established for different problem instances. The 3XTS is compared to another tabu search method (that seems to be a champion) in terms of solution quality and computation time.
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Konkar, Haifa Nassar Plantholt Michael. „Graph theory as an introduction to methods of proof and problem-solving“. Normal, Ill. Illinois State University, 1988. http://wwwlib.umi.com/cr/ilstu/fullcit?p8901467.
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Thesis (D.A.)--Illinois State University, 1988.Title from title page screen, viewed September 16, 2005. Dissertation Committee: Michael Plantholt (chair), John Dossey, Patricia Klass, Albert Otto, Charles Vanden Eynden. Includes bibliographical references (leaves 172-173) and abstract. Also available in print.
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Domino, Madeline Ann. „Three studies of problem solving in collaborative software development“. [Tampa, Fla] : University of South Florida, 2004. http://purl.fcla.edu/usf/dc/et/SFE0001428.
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Rivière, Béatrice. „Discontinuous Galerkin methods for solving the miscible displacement problem in porous media /“. Digital version accessible at:, 2000. http://wwwlib.umi.com/cr/utexas/main.
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Sucu, Seda. „Solving crew scheduling problem in offshore supply vessels : heuristics and decomposition methods“. Thesis, University of Strathclyde, 2017. http://digitool.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=29270.
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For the efficient utilisation of resources in various transportation settings, scheduling is a significant area of research. Having crew as the main resource for operation maintenance, scheduling crew have been a powerful decision making tool for optimisation studies. This research provides a detailed real case study analysis regarding the difficulties in planning crew in maritime industry. As a special case study, this thesis researches crew scheduling in offshore supply vessels which are used for specific operations of a global scaled company in oil and gas industry deeply with modified formulations, heuristics and decomposition methods. An extended version of computational study for a simple formulation approach (Task Based Model) is applied as deeper analysis to Leggate (2016). Afterwards, more realistic approach to the same problem is revised. Following the revision, a customized and thorough computational study on the heuristic method with various settings is designed and implemented in C++. After elaborated analysis completed on the suggested models firstly, a modification on Time Windows model is presented to increase the efficacy. This modification provides a sharp decrease in upper bounds within a short time compared to the previously suggested models. Through this suggestion, more economic schedules within a short period of time are generated. Achieving high performances from the modified model, an application of a decomposition algorithm is provided. We implemented a hybrid solution of Benders Decomposition with a customized heuristic for the modified model. Although this hybrid solution does not provide high quality solutions, it evaluates the performance of possible decomposed models with potential improvements for future research. An introduction to robust crew scheduling in maritime context is also given with a description of resources of uncertainty in this concept and initial robust formulations are suggested.
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Malinen, I. (Ilkka). „Improving the robustness with modified bounded homotopies and problem-tailored solving procedures“. Doctoral thesis, Oulun yliopisto, 2011. http://urn.fi/urn:isbn:9789514293382.
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Abstract
The aim of this work is to improve the overall robustness in equation-oriented chemical engineering simulation work. Because the performance of locally convergent solving methods is strongly dependent on a favourable initial guess, bounded homotopy methods were investigated as a way to enlarge the domain of convergence. Bounded homotopies make it possible to keep the homotopy path inside a feasible problem domain. Thus the fatal errors possibly caused by unfeasible variable values in thermodynamic subroutines can be avoided.
To enable the utilization of a narrow bounding zone, modifications were proposed for bounded homotopies. The performance of the modifications was studied with simple test problems and several types of distillation systems in the MATLAB environment.
The findings illustrate that modified bounded homotopies with variables mapping make it possible to bound the homotopy path strictly to run inside a feasible problem domain. The homotopy path can be tracked accurately and flexibly also inside a narrow bounding zone.
It was also noticed that by utilizing the concept of bounding the homotopy path with respect to the homotopy parameter, the possibility of approaching starting point and solution multiplicities is increased in cases where the traditional problem-independent homotopy method fails. The concept aims to connect separate homotopy path branches thus offering a trackable path with real space arithmetic.
Even though the modified bounded homotopies were found to overcome several challenges often encountered with traditional problem-independent homotopy continuation methods, alone they are not enough to guarantee that the solution is approached from an arbitrary starting point. Therefore, problem-tailored solving procedures were implemented in the consideration of complex column configurations. Problem-tailored solving procedures aim to offer feasible consecutive sub-problems and thus direct the solving towards the state distribution that fulfils exact product purity specifications.
As a whole, the modified bounded homotopies and problem-tailored solving procedures were found to improve the overall robustness of an equation-oriented solving approach. Thus the threshold for designing and implementing complex process systems such as complex distillation configurations for practical use could be lowered.
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Sarikaya, Sedat. „Combination Of Conventional Regularization Methods And Genetic Algorithms For Solving The Inverse Problem Of Electrocardiography“. Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/2/12611669/index.pdf.
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Distribution of electrical potentials over the surface of the heart, i.e., the epicardial potentials, is a valuable tool to understand whether there is a defect in the heart. However, it is not easy to detect these potentials non-invasively. Instead, body surface potentials, which occur as a result of the electrical activity of the heart, are measured to diagnose heart defects. However the source electrical signals loose some critical details because of the attenuation and smoothing they encounter due to body tissues such as lungs, fat, etc. Direct measurement of these epicardial potentials requires invasive procedures. Alternatively, one can reconstruct the epicardial potentials non-invasively from the body surface potentialsthis method is called the inverse problem of electrocardiography (ECG). The goal of this study is to solve the inverse problem of ECG using several well-known regularization methods and using their combinations with genetic algorihm (GA) and finally compare the performances of these methods. The results show that GA can be combined with the conventional regularization methods and their combination improves the regularization of ill-posed inverse ECG problem. In several studies, the results show that their combination provide a good scheme for solving the ECG inverse problem and the performance of regularization methods can be improved further. We also suggest that GA can be initiated succesfully with a training set of epicardial potentials, and with the optimum, over- and under-regularized Tikhonov regularization solutions.
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Tran, Nhan Thanh. „Numerical methods for solving wave scattering problems“. Diss., Kansas State University, 2016. http://hdl.handle.net/2097/32508.
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Doctor of PhilosophyDepartment of Mathematics
Alexander G. Ramm
In this thesis, the author presents several numerical methods for solving scalar and electromagnetic wave scattering problems. These methods are taken from the papers of Professor Alexander Ramm and the author, see [1] and [2]. In Chapter 1, scalar wave scattering by many small particles of arbitrary shapes with impedance boundary condition is studied. The problem is solved asymptotically and numerically under the assumptions a << d << λ, where k = 2π/λ is the wave number, λ is the wave length, a is the characteristic size of the particles, and d is the smallest distance between neighboring particles. A fast algorithm for solving this wave scattering problem by billions of particles is presented. The algorithm comprises the derivation of the (ORI) linear system and makes use of Conjugate Orthogonal Conjugate Gradient method and Fast Fourier Transform. Numerical solutions of the scalar wave scattering problem with 1, 4, 7, and 10 billions of small impedance particles are achieved for the first time. In these numerical examples, the problem of creating a material with negative refraction coefficient is also described and a recipe for creating materials with a desired refraction coefficient is tested. In Chapter 2, electromagnetic (EM) wave scattering problem by one and many small perfectly conducting bodies is studied. A numerical method for solving this problem is presented. For the case of one body, the problem is solved for a body of arbitrary shape, using the corresponding boundary integral equation. For the case of many bodies, the problem is solved asymptotically under the physical assumptions a << d << λ, where a is the characteristic size of the bodies, d is the minimal distance between neighboring bodies, λ = 2π/k is the wave length and k is the wave number. Numerical results for the cases of one and many small bodies are presented. Error analysis for the numerical method are also provided.
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Sandberg, Richard. „A survey of optimization methods for solving the inverse shortest path routing problem“. Thesis, Linköpings universitet, Optimeringslära, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-59536.
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Ruttningen av trafik i IP-nätverk sker ofta med hjälp av bågvikter som bestämmer vilken väg trafiken tar (kortastevägruttning). Problemet här är att avgöra ifall det existerar en uppsättning vikter givet ett önskat ruttningsschema. Den hör rapporten undersöker prestandan hos ett antal modeller och optimeringsprogram avsedda att lösa denna typ av problem som ofta kallas inversa kortastevägruttningsproblemet. Undersökningen visar att det existerar en stor skillnad mellan modellerna och optimeringsprogrammen och att modellen baserad på cykelbaser löst med CPLEXdualopt lösaren är snabbast.The routing of traffic in IP networks is often done with a set of weights that determinewhich way the traffic will go (shortest path routing). The problem here is todetermine if there exists a set of weights for a desired routing pattern. This thesis willinvestigate the performance of a number of different models and solvers for solvingthis type of problem which is usually called the inverse shortest path routing (ISPR)problem. The models tested are the same as described in [1]. The different solversused are mainly the linear CPLEX solvers but also a few multi commodity networksolvers. The tests showed that there is a big performance difference between the models andsolvers and that the cycle bases model solved with the CPLEX dualopt solver wasthe fastest overall.
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Asgharzadeh, Talebi Zohreh. „Exact and Heuristic Methods for solving the View-Selection Problem for Aggregate Queries“. NCSU, 2006. http://www.lib.ncsu.edu/theses/available/etd-05092006-123513/.
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In this thesis we present a formal study of the following view-selection problem: Given a set of queries, a database, and an upper bound on the amount of disk space that can be used to store materialized views, return definitions of views that, when materialized in the database, would reduce the evaluation costs of the queries. Optimizing the layout of stored data using view selection has a direct impact on the performance of the entire database system. At the same time, the optimization problem is intractable, even under natural restrictions on the types of queries of interest. We introduce an integer-programming model to obtain optimal solutions for the view-selection problem for aggregate queries on data warehouses. Through a computational experiment we show that this model can be used to solve realistic-size instances of the problem. We also report the results of the post-optimality analysis that we performed to determine the impact of changing certain input characteristics on the optimal solution. We solve large instances by applying several methods of reducing the size of the search space. We compare our approach to the leading heuristic procedure in the field [20].
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Bercsey, Tibor, und Klaudia Nagy. „Applying inventive problem solving methods at the early stage of industrial product design“. TUDpress - Verlag der Wissenschaften GmbH, 2012. https://tud.qucosa.de/id/qucosa%3A30783.
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The paper introduces a methodological overview followed by thoughts of the recent problems of using these theories at the industrial ground offering some solutions for improvement. Shows a case study where several semesters of the Integrated Product Design courses were observed at the Department of Machine and Product Design at the Budapest University of Technology and Economics (BME). The aim of the presented study has been to evaluate a selected product design project from the aspect of the effectiveness of the previous methodological training. Based on these findings we provide some suggestions for the design education to support the early stage of the design process. [...from the introduction]
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Bercsey, Tibor, und Klaudia Nagy. „Applying inventive problem solving methods at the early stage of industrial product design“. Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2018. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-232922.
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The paper introduces a methodological overview followed by thoughts of the recent problems of using these theories at the industrial ground offering some solutions for improvement. Shows a case study where several semesters of the Integrated Product Design courses were observed at the Department of Machine and Product Design at the Budapest University of Technology and Economics (BME). The aim of the presented study has been to evaluate a selected product design project from the aspect of the effectiveness of the previous methodological training. Based on these findings we provide some suggestions for the design education to support the early stage of the design process. [...from the introduction]
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Merrill, Jared Aaron. „An Investigation of the ASIT Problem-Solving Method on Middle School Technology Education Student's Ability to Produce Creative Solutions“. BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/4289.
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This study compared two groups of students being instructed in various methods of problem solving over a two-week period. The control group was instructed using the standard Career and Technology Education (CTE) Introduction curriculum on using brainstorming to solve problems. The treatment group was instructed using a structured problem solving method developed to help focus problem solving on finding a solution that satisfies the conditions. Students were selected from 7th grade students at a suburban middle school in Utah. The independent variable in this study was the type of problem solving instruction received. The dependent variables of interest were the fluency of producing solutions (S), number of inventive solutions (I) produced while problem solving. Additional variables of interest include student's perceived competence (c) while problem solving and students perceived usefulness (u) of problem solving in their lives. A pre-test and a post-test consisting of open-ended problems were utilized to assess the fluency of solutions (S) and the number of inventive solutions (I). A modified Fennema-Sherman attitude questionnaire was utilized to assess student's perceived competence (c) and perceived usefulness (u). The findings indicated that students who are taught a structured problem solving method produce a statistically significant (p-value of .033) greater number of inventive solutions when compared to students not instructed in this method. These students also appear to focus their problem solving by producing less total solutions (s) but a greater portion of these solutions is inventive. Other findings include data that supports the idea that dedicated problem solving instruction increases students perceptions of their own abilities to problem solving. Both control and treatment groups experience a statistically significant increase in their perceived competence in problem solving (p-value of .430 and .382 respectively).
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Hussein, Sayed A. „Implicit methods in initial value problems“. Thesis, University of Essex, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302882.
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Zhao, Kezhong. „A domain decomposition method for solving electrically large electromagnetic problems“. Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1189694496.
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WESTCOTT, KATHRYN M. „TEACHING PROBLEM IDENTIFICATION SKILLS TO TEACHER INTERNS: AN ANALYSIS OF INSTRUCTIONAL METHODS“. University of Cincinnati / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1014047935.
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Zigic, Dragan. „Homotopy methods for solving the optimal projection equations for the reduced order model problem“. Thesis, This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-11242009-020145/.
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Gheorghe, Simona. „On multigrid methods for solving electromagnetic scattering problems“. [S.l.] : [s.n.], 2006. http://e-diss.uni-kiel.de/diss_1664/d1664.pdf.
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Cabezas, García José Xavier. „Heuristic methods for solving two discrete optimization problems“. Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/31093.
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In this thesis we study two discrete optimization problems: Traffic Light Synchronization and Location with Customers Orderings. A widely used approach to solve the synchronization of traffic lights on transport networks is the maximization of the time during which cars start at one end of a street and can go to the other without stopping for a red light (bandwidth maximization). The mixed integer linear model found in the literature, named MAXBAND, can be solved by optimization solvers only for small instances. In this manuscript we review in detail all the constraints of the original linear model, including those that describe all the cyclic routes in the graph, and we generalize some bounds for integer variables which so far had been presented only for problems that do not consider cycles. Furthermore, we summarized the first systematic algorithm to solve a simpler version of the problem on a single street. We also propose a solution algorithm that uses Tabu Search and Variable Neighbourhood Search and we carry out a computational study. In addition we propose a linear formulation for the shortest path problem with traffic lights constraints (SPTL). On the other hand, the simple plant location problem with order (SPLPO) is a variant of the simple plant location problem (SPLP) where the customers have preferences on the facilities which will serve them. In particular, customers define their preferences by ranking each of the potential facilities. Even though the SPLP has been widely studied in the literature, the SPLPO has been studied much less and the size of the instances that can be solved is very limited. In this manuscript, we propose a heuristic that uses a Lagrangean relaxation output as a starting point of a semi-Lagrangean relaxation algorithm to find good feasible solutions (often the optimal solution). We also carry out a computational study to illustrate the good performance of our method. Last, we introduce the partial and stochastic versions of SPLPO and apply the Lagrangean algorithm proposed for the deterministic case to then show examples and results.
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Pindza, Edson. „Robust Spectral Methods for Solving Option Pricing Problems“. University of the Western Cape, 2012. http://hdl.handle.net/11394/4092.
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Doctor Scientiae - DScRobust Spectral Methods for Solving Option Pricing Problems by Edson Pindza PhD thesis, Department of Mathematics and Applied Mathematics, Faculty of Natural Sciences, University of the Western Cape Ever since the invention of the classical Black-Scholes formula to price the financial derivatives, a number of mathematical models have been proposed by numerous researchers in this direction. Many of these models are in general very complex, thus closed form analytical solutions are rarely obtainable. In view of this, we present a class of efficient spectral methods to numerically solve several mathematical models of pricing options. We begin with solving European options. Then we move to solve their American counterparts which involve a free boundary and therefore normally difficult to price by other conventional numerical methods. We obtain very promising results for the above two types of options and therefore we extend this approach to solve some more difficult problems for pricing options, viz., jump-diffusion models and local volatility models. The numerical methods involve solving partial differential equations, partial integro-differential equations and associated complementary problems which are used to model the financial derivatives. In order to retain their exponential accuracy, we discuss the necessary modification of the spectral methods. Finally, we present several comparative numerical results showing the superiority of our spectral methods.
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Indratno, Sapto Wahyu. „Numerical methods for solving linear ill-posed problems“. Diss., Kansas State University, 2011. http://hdl.handle.net/2097/8109.
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Doctor of PhilosophyDepartment of Mathematics
Alexander G. Ramm
A new method, the Dynamical Systems Method (DSM), justified recently, is applied to solving ill-conditioned linear algebraic system (ICLAS). The DSM gives a new approach to solving a wide class of ill-posed problems. In Chapter 1 a new iterative scheme for solving ICLAS is proposed. This iterative scheme is based on the DSM solution. An a posteriori stopping rules for the proposed method is justified. We also gives an a posteriori stopping rule for a modified iterative scheme developed in A.G.Ramm, JMAA,330 (2007),1338-1346, and proves convergence of the solution obtained by the iterative scheme. In Chapter 2 we give a convergence analysis of the following iterative scheme: u[subscript]n[superscript]delta=q u[subscript](n-1)[superscript]delta+(1-q)T[subscript](a[subscript]n)[superscript](-1) K[superscript]*f[subscript]delta, u[subscript]0[superscript]delta=0, where T:=K[superscript]* K, T[subscript]a :=T+aI, q in the interval (0,1),\quad a[subscript]n := alpha[subscript]0 q[superscript]n, alpha_0>0, with finite-dimensional approximations of T and K[superscript]* for solving stably Fredholm integral equations of the first kind with noisy data. In Chapter 3 a new method for inverting the Laplace transform from the real axis is formulated. This method is based on a quadrature formula. We assume that the unknown function f(t) is continuous with (known) compact support. An adaptive iterative method and an adaptive stopping rule, which yield the convergence of the approximate solution to f(t), are proposed in this chapter.
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Zhu, Hong. „Solving optimization problems with generalized orthogonality constraints“. HKBU Institutional Repository, 2016. https://repository.hkbu.edu.hk/etd_oa/341.
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This thesis focuses on optimization problems with generalized orthogonality constraints, which may also contains linear equality constraints. These problems appear in many areas, such as machine learning, signal processing, computer vision and so on.;Many problems in this form are NP hard. One challenge posed by generalized orthogonality constraints is local minimizers loaded by nonconvex constraints. More-over, the generalized orthogonality constraints are numerically expensive to preserve during iterations.;This thesis is mainly divided into two parts. The first part is focused on solving generalized orthogonality constrained optimization problems with differentiable objective functions. For this class of optimization problems, a generalized gradient.;This thesis is mainly divided into two parts. The first part is focused on solving generalized orthogonality constrained optimization problems with differentiable objective functions. For this class of optimization problems, a generalized gradient flow is proposed, which is contained on the constraints set if the initial condition satisfies generalized orthogonality constrains. The week convergence of the generalizedgradient flow is given. A discrete iterative scheme is also proposed to make the gradient flow method computable. In addition, we analyze the relationship between our discrete iteration scheme and some existing constraint preserving methods, and the relationship between our discrete iteration scheme and the inexact forward-backward method, respectively. Several problems which also can be solved by the generalized gradient flow are given. Furthermore, we also propose an optimal gradient flow by an alyzing the first order optimality condition.;The second part of this thesis is devoted to study of the generalized orthogonality constrained optimization problems with nondifferentiable objective functions. An approximate augmented Lagrangian method is used to deal with this class of problems. The global convergence is presented. We also extend the proximal alternating linearized minimization method (EPALM) to deal with the generalized orthogonality constraints appeared in the subproblem of the approximate augmented Lagrangian method. Moreover, to accelerate the EPALM method, an inertial proximal alternating linearized minimization method (IPALM) is proposed to deal with unconstrained nonconvex, nonsmooth problems with coupled objective functions.;Keywords: Generalized Orthogonality Constraints; Stiefel Manifold; Tangent Space;Gradient Flow; Approximate Augmented Lagrangian Method; Proximal Alternating Linearized Minimization Method.
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Jung, Michael, und Todor D. Todorov. „On the Convergence Factor in Multilevel Methods for Solving 3D Elasticity Problems“. Universitätsbibliothek Chemnitz, 2006. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200601510.
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The constant gamma in the strengthened Cauchy-Bunyakowskii-Schwarz inequality is a basic tool for constructing of two-level and multilevel preconditioning matrices. Therefore many authors consider estimates or computations of this quantity. In this paper the bilinear form arising from 3D linear elasticity problems is considered on a polyhedron. The cosine of the abstract angle between multilevel finite element subspaces is computed by a spectral analysis of a general eigenvalue problem. Octasection and bisection approaches are used for refining the triangulations. Tetrahedron, pentahedron and hexahedron meshes are considered. The dependence of the constant $\gamma$ on the Poisson ratio is presented graphically.
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Li, Xiaobei. „Instrumentation and inverse problem solving for impedance imaging /“. Thesis, Connect to this title online; UW restricted, 2006. http://hdl.handle.net/1773/5973.
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Beggs, Louise Alice. „Evaluation of the problem solving method in nutrition education“. Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26164.
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The purpose of this study was to evaluate the problem solving method applied to a self-instructional material in nutrition education.
A comparative evaluation design was employed to determine the value of a problem solving model reflected in a commercially developed material, referred to as the 'Calcium Calculator'. Data were collected using a quasi-experimental randomized group pretest, posttest research design. A panel of judges then evaluated the impact of the problem solving method in nutrition education.
Three research questions were generated for the purpose of this study. The first involved comparing impacts produced by the two forms of the 'Calcium Calculator'. Measures of impact, selected based on learner objectives of the 'Calcium Calculator', were learners': attitudes toward dietary calcium and osteoporosis; perception of problem solving ability and self-reported dietary calcium intake.
The second research question was posed to investigate the nature of relationships between learners' levels of self-esteem and measures of instructional impact. Influences of selected biodemographic variables on change in the measures of impact were explored in the third research question.
Eighteen groups of women (n=241) from community centres were randomly assigned to one of three intervention groups: Groups A and B were exposed to active problem solving methods while group C viewed a film, a passive information-oriented instructional technique. The latter group was included in.the study since active learning was hypothesized to result in greater impact than passive learning. Pretest data were collected using a self-administered questionnaire and food intake form. Posttest data were collected an average of 4.7 weeks later using a modification of the pretest questionnaire which included a self-esteem scale, along with the food intake form. Forty-four percent of women (n=l06) who completed pretest questionnaires returned for the posttest session.
Participants in all three intervention groups experienced increases in attitude scores from pre- to posttest, and these changes were significant within groups B and C. Perceptions of problem solving ability were maintained within intervention groups B and C, yet decreased significantly within intervention group A. Significant increases in self-reported dietary calcium intakes occurred in all three intervention groups among non-pregnant women whose pretest dietary calcium intakes were below their Recommended Nutrient Intake.
Impacts produced by form A and B of the 'Calcium Calculator' were significantly different on only one dependent variable: perception of problem solving ability (p≤0.05). Changes in the dependent variables produced by problem solving versus non-problem solving interventions were not significantly different. Changes in dietary calcium intake and attitude toward dietary calcium and osteoporosis were not significantly correlated with self-esteem levels. However, positive significant correlations were identified between learners' levels of self-esteem and change in learners' perceptions of their problem solving ability (p≤0.0l).
Measures of impact were infrequently influenced by the biodemographic variables. Of the associations that were identified, most involved dietary characteristics of participants. Yet change in perception of problem solving ability was also affected by a combination of three demographic variables: age, employment status and education.
A panel of users (n=9) of educational materials was asked to make judgements on selected study results. Although judges did not distinguish between impacts produced by the two problem solving materials, they acknowledged that: (1) an important relationship exists between self-esteem and learners' perceptions of their problem solving ability and (2) the problem solving method is valuable when directed to specific kinds of learners.
The quasi-experimental research design used in this study appeared appropriate for the evaluation of innovative instructional methods. Two main advantages of the design were its comparative nature and its use of a panel of experts to judge the relative effectiveness of both forms of the 'Calcium Calculator' as well as the value of the problem solving method and self-esteem in material design.Education, Faculty of
Curriculum and Pedagogy (EDCP), Department of
Graduate
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Massa, Julio Cesar. „Acceleration of convergence in solving the eigenvalue problem by matrix iteration using the power method“. Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/101452.
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A modification of the matrix iteration using the power method, in conjunction with Hotelling deflation, for the solution of the problem K.x = ω².M.x is here proposed. The problem can be written in the form D.x =λ.x, and the modification consists of raising the matrix D to an appropriate power p before carrying out the iteration process.
The selection of a satisfactory value of p is investigated, based on the spacing between the eigenvalues. The effect of p on the accuracy of the results is also discussed.M.S.
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Willert, Jeffrey Alan. „Hybrid Deterministic/Monte Carlo Methods for Solving the Neutron Transport Equation and k-Eigenvalue Problem“. Thesis, North Carolina State University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3575891.
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The goal of this thesis is to build hybrid deterministic/Monte Carlo algorithms for solving the neutron transport equation and associated k-eigenvalue problem. We begin by introducing and deriving the transport equation before discussing a series of deterministic methods for solving the transport equation. To begin we consider moment-based acceleration techniques for both the one and two-dimensional fixed source problems. Once this machinery has been developed, we will apply similar techniques for computing the dominant eigenvalue of the neutron transport equation. We'll motivate the development of hybrid methods by describing the deficiencies of deterministic methods before describing Monte Carlo methods and their advantages. We conclude the thesis with a chapter describing the detailed implementation of hybrid methods for both the fixed-source and k-eigenvalue problem in both one and two space dimensions. We'll use a series of test problems to demonstrate the effectiveness of these algorithms before hinting at some possible areas of future work.
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Yahosseini, Kyanoush Seyed [Verfasser]. „Experimental Study and Modeling of Three Classes of Collective Problem-Solving Methods / Kyanoush Seyed Yahosseini“. Berlin : Freie Universität Berlin, 2020. http://d-nb.info/1212854357/34.
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McDonald, Bruce Beresford. „Managerial problem-solving methods and outline specification for a computer-based managerial job-management system“. Thesis, Open University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259498.
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Dyhoum, Taysir Emhemed. „The method of fundamental solutions and MCMC methods for solving electrical tomography problems“. Thesis, University of Leeds, 2016. http://etheses.whiterose.ac.uk/15552/.
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Electrical impedance tomography (EIT) is a non-intrusive and portable imaging technique which has been used widely in many medical, geological and industrial applications for imaging the interior electrical conductivity distribution within a region from the knowledge of the injected currents through attached electrodes and resulting voltages, or boundary potential and current flux. If the quantities involved are all real then EIT is called electrical resistance tomography (ERT). The work in this thesis focuses on solving inverse geometric problems in ERT where we seek detecting the size, the shape and the location of inner objects within a given bounded domain. These ERT problems are governed by Laplace’s equation subject either to the most practical and general boundary conditions, forming the socalled complete-electrode model (CEM), in two dimensions or to the more idealised boundary conditions in three-dimensions called the continuous model. Firstly, the method of the fundamental solutions (MFS) is applied to solve the forward problem of the two-dimensional complete-electrode model of ERT in simplyconnected and multiple-connected domains (rigid inclusion, cavity and composite bimaterial), as well as providing the corresponding MFS solutions for the three-dimensional continuous model. Secondly, a Bayesian approach and the Markov Chain Monte Carlo (MCMC) estimation technique are employed in combinations with the numerical MFS direct solver in order to obtain the inverse solution. The MCMC algorithm is not only used for reconstruction, but it also deals with uncertainty assessment issues. The reliability and accuracy of a fitted object is investigated through some meaningful statistical aspects such as the object boundary histogram and object boundary credible intervals.
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Attia, Ahmed Mohamed Mohamed. „Advanced Sampling Methods for Solving Large-Scale Inverse Problems“. Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/73683.
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Ensemble and variational techniques have gained wide popularity as the two main approaches for solving data assimilation and inverse problems. The majority of the methods in these two approaches are derived (at least implicitly) under the assumption that the underlying probability distributions are Gaussian. It is well accepted, however, that the Gaussianity assumption is too restrictive when applied to large nonlinear models, nonlinear observation operators, and large levels of uncertainty. This work develops a family of fully non-Gaussian data assimilation algorithms that work by directly sampling the posterior distribution. The sampling strategy is based on a Hybrid/Hamiltonian Monte Carlo (HMC) approach that can handle non-normal probability distributions.
The first algorithm proposed in this work is the "HMC sampling filter", an ensemble-based data assimilation algorithm for solving the sequential filtering problem. Unlike traditional ensemble-based filters, such as the ensemble Kalman filter and the maximum likelihood ensemble filter, the proposed sampling filter naturally accommodates non-Gaussian errors and nonlinear model dynamics, as well as nonlinear observations. To test the capabilities of the HMC sampling filter numerical experiments are carried out using the Lorenz-96 model and observation operators with different levels of nonlinearity and differentiability. The filter is also tested with shallow water model on the sphere with linear observation operator. Numerical results show that the sampling filter performs well even in highly nonlinear situations where the traditional filters diverge.
Next, the HMC sampling approach is extended to the four-dimensional case, where several observations are assimilated simultaneously, resulting in the second member of the proposed family of algorithms. The new algorithm, named "HMC sampling smoother", is an ensemble-based smoother for four-dimensional data assimilation that works by sampling from the posterior probability density of the solution at the initial time. The sampling smoother naturally accommodates non-Gaussian errors and nonlinear model dynamics and observation operators, and provides a full description of the posterior distribution. Numerical experiments for this algorithm are carried out using a shallow water model on the sphere with observation operators of different levels of nonlinearity. The numerical results demonstrate the advantages of the proposed method compared to the traditional variational and ensemble-based smoothing methods.
The HMC sampling smoother, in its original formulation, is computationally expensive due to the innate requirement of running the forward and adjoint models repeatedly. The proposed family of algorithms proceeds by developing computationally efficient versions of the HMC sampling smoother based on reduced-order approximations of the underlying model dynamics. The reduced-order HMC sampling smoothers, developed as extensions to the original HMC smoother, are tested numerically using the shallow-water equations model in Cartesian coordinates. The results reveal that the reduced-order versions of the smoother are capable of accurately capturing the posterior probability density, while being significantly faster than the original full order formulation.
In the presence of nonlinear model dynamics, nonlinear observation operator, or non-Gaussian errors, the prior distribution in the sequential data assimilation framework is not analytically tractable. In the original formulation of the HMC sampling filter, the prior distribution is approximated by a Gaussian distribution whose parameters are inferred from the ensemble of forecasts. The Gaussian prior assumption in the original HMC filter is relaxed. Specifically, a clustering step is introduced after the forecast phase of the filter, and the prior density function is estimated by fitting a Gaussian Mixture Model (GMM) to the prior ensemble. The base filter developed following this strategy is named cluster HMC sampling filter (ClHMC ). A multi-chain version of the ClHMC filter, namely MC-ClHMC , is also proposed to guarantee that samples are taken from the vicinities of all probability modes of the formulated posterior. These methodologies are tested using a quasi-geostrophic (QG) model with double-gyre wind forcing and bi-harmonic friction. Numerical results demonstrate the usefulness of using GMMs to relax the Gaussian prior
assumption in the HMC filtering paradigm.
To provide a unified platform for data assimilation research, a flexible and a highly-extensible testing suite, named DATeS , is developed and described in this work. The core of DATeS is implemented in Python to enable for Object-Oriented capabilities. The main components, such as the models, the data assimilation algorithms, the linear algebra solvers, and the time discretization routines are independent of each other, such as to offer maximum flexibility to configure data assimilation studies.Ph. D.
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Al, Mugahwi Mohammed. „Methods for Solving Node Centrality Measure Problems for LargeNetworks“. Kent State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=kent1594905870792566.
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Whitcher, Carrie Lynn. „The influence of contextual teaching with the problem solving method on students' knowledge and attitudes toward horticulture, science, and school“. Texas A&M University, 2005. http://hdl.handle.net/1969.1/4226.
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Adolescence is marked with many changes in the development of higher order
thinking skills. As students enter high school they are expected to utilize these skills to
solve problems, become abstract thinkers, and contribute to society.
The goal of this study was to assess horticultural science knowledge achievement
and attitude toward horticulture, science, and school in high school agriculture students.
There were approximately 240 high school students in the sample including both
experimental and control groups from California and Washington. Students in the
experimental group participated in an educational program called âÂÂHands-On
Hortscienceâ which emphasized problem solving in investigation and experimentation
activities with greenhouse plants, soilless media, and fertilizers. Students in the control
group were taught by the subject matter method. The activities included in the Hands-On
Hortscience curriculum were created to reinforce teaching the scientific method through
the context of horticulture. The objectives included evaluating whether the students participating in the Hands-On Hortscience experimental group benefited in the areas of
science literacy, data acquisition and analysis, and attitude toward horticulture, science,
and school.
Pre-tests were administered in both the experimental and control groups prior to
the research activities and post-tests were administered after completion. The survey
questionnaire included a biographical section and attitude survey.
Significant increases in hortscience achievement were found from pre-test to
post-test in both control and experimental study groups. The experimental treatment
group had statistically higher achievement scores than the control group in the two areas
tested: scientific method (p=0.0016) and horticulture plant nutrition (p=0.0004).
In addition, the students participating in the Hands-On Hortscience activities had
more positive attitudes toward horticulture, science, and school (p=0.0033). Students
who were more actively involved in hands-on projects had higher attitude scores
compared to students who were taught traditional methods alone.
In demographic comparisons, females had more positive attitudes toward
horticulture science than males; and students from varying ethnic backgrounds had
statistically different achievement (p=0.0001). Ethnicity was determined with few
students in each background, 8 in one ethnicity and 10 students in another. Youth
organization membership such as FFA or 4-H had no significant bearing on achievement
or attitude.
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Maxfield, Marian Belle. „The Effects of Small Group Cooperation Methods and Question Strategies on Problem Solving Skills, Achievement, and Attitude during Problem-Based Learning“. Kent State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=kent1301113251.
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Ryoo, Moo Bong. „A constraint branch-and-bound method for set partitioning problems“. Thesis, Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA227092.
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Thesis (M.S. in Operations Research)--Naval Postgraduate School, March 1990.Thesis Advisor(s): Wood, R. Kevin. Second Reader: Brown, Gerald Gerard. "March 1990." Description based on signature page as viewed on October 21, 2009. Author(s) subject terms: Set partitioning problem, constraint branch and bound method, enumeration tree. Includes bibliographical references (p. 34-36). Also available online.