In this study we will consider the construction of approximate optimal design for one-dimensional regression by exchange algorithm. Sufficient conditions under which an optimal design must have the minimal support points are known in Theorem 2.3.2 of Fedorov (1972). However, there are only a few cases which the analytic optimal designs are known. The exchange procedure for computing optimal designs is easily adopted to most criteria. We describe implementations for constructing the well-known special cases D-, A-, and c-optimal designs with the minimum number of support points. Examples which illustrate how the algorithm can be used to obtain these optimal designs and the performance of the algorithm are discussed. The commonly used D-, A-, and c-optimal criteria will be employed to study the convergence properties of the exchange algorithm for regression model which the set of the product of regression functions forms a Chebyshev system.

The master's thesis deals with the issues of marketing strategy and communications with subsequent applications to an alternative care center for pets, named the Optima Vetcare. The theoretical part includes description of marketing concepts, which include a marketing strategy, a marketing mix, a communication mix, trends in marketing and a marketing research. The practical part is specifically focused on the specifics of the marketing Optima Vetcare and maps its marketing efforts since the year 2014, when it was founded. The questionnaire survey is realized at the end of the thesis and then recommendations are proposed for the improvement of Optima Vetcare's marketing communications. The aim of this thesis is to present an alternative care center for pets Optima Vetcare and analyze its marketing. Another goal is to provide possible proposals and recommendations for marketing communication improvement.

In order to improve the design of mechanical or mechatronic systems, mathematical optimization techniques have become an efficient and attractive tool with the increasing development of computer resources. However, the application of such optimization methods to multibody systems (MBS) remains a challenge when the MBS analysis requires the solving of assembly constraints. Hence, this PhD research focuses on the optimization of such closed-loop MBS, particularly when the objective function is of geometrical or kinematic nature. For kinematic optimization of MBS, we propose two penalty strategies to deal with assembly constraints during optimization. Both strategies are compared and illustrated via applications such as the isotropy maximization of parallel manipulators: the 3-dof Delta robot and the 6-dof Hunt platform. Following the same strategies, geometrical optimization of MBS is then investigated. However, due to a higher complexity, we propose to relax the problem, combining two modeling approaches: rigid-body and extensible-link formulations. This leads to a two-step strategy which is then successfully applied to synthesize mechanisms for path-following or function-generation problems. Through these applications, the existence of multiple local optima is highlighted. Therefore, instead of focusing on the unique global optimum solution, we have developed original methods to search and propose several local solutions for the design problem. This approach is called morphological optimization. This enables the designer to choose finally the best solution among several local optima using additional design criteria. Such morphological optimization techniques open the doors for the topology optimization of MBS which remains a challenging problem for future research / Afin d'améliorer la conception de systèmes mécaniques ou mécatroniques, les techniques d'optimisation mathématique sont devenues un outil efficace et attrayant étant donné le développement croissant des ressources informatiques. Cependant, l'application de telles méthodes d'optimisation sur les systèmes multicorps demeure un défi quand l'analyse du système nécessite la résolution de contraintes d'assemblage. C'est pourquoi cette recherche doctorale se concentre sur l'optimisation de tels systèmes multicorps, particulièrement lorsque la fonction objectif est de nature géométrique ou cinématique. Pour l'optimisation cinématique des systèmes multicorps, nous proposons deux stratégies de pénalité pour traiter les contraintes d'assemblage en cours d'optimisation. Ces deux stratégies sont comparées et illustrées par des applications telles que la maximisation d'isotropie de manipulateurs parallèles. Suivant les mêmes stratégies, l'optimisation géométrique des systèmes multicorps est alors étudiée. Cependant, vu la plus grande complexité, nous proposons de relaxer le problème en combinant deux approches de modélisation : une formulation en termes de corps rigides et une autre en termes de liens extensibles. Ceci nous mène à une stratégie en deux étapes qui est alors appliquée avec succès pour la synthèse de mécanismes. A travers ces applications, on a mis en évidence l'existence d'optimums locaux multiples. Dès lors, plutôt que de se focaliser sur l'unique optimum global, nous avons développé des méthodes originales afin de rechercher et proposer plusieurs solutions locales pour le problème de conception. Cette approche est baptisée "optimisation morphologique". Elle permet au concepteur de choisir finalement la meilleure solution parmi plusieurs optimums locaux en utilisant des critères supplémentaires de conception. De telles techniques d'optimisation morphologique ouvrent les portes pour l'optimisation topologique des systèmes multicorps qui demeure un challenge motivant pour des recherches futures.

Optimization plays a central role in the control and operation of electricity power networks. In this thesis we focus on two very important optimization problems in power systems. The first is the optimal power flow problem (OPF). This is an old and well-known nonconvex optimization problem in power system. The existence of local solutions of OPF has been a question of interest for decades. Both local and global solution techniques have been put forward to solve OPF problem but without any documented cases of local solutions. We have produced test cases of power networks with local solutions and have collected these test cases in a publicly available online archive (http://www.maths.ed.ac.uk/optenergy/LocalOpt/), which can be used now by researchers and practitioners to test the robustness of their solution techniques. Also a new nonlinear relaxation of OPF is presented and it is shown that this relaxation in practice gives tight lower bounds of the global solution of OPF. The second problem considered is how to split a network into islands so as to prevent cascading blackouts over wide areas. A mixed integer linear programming (MILP) model for islanding of power system is presented. In recent years, islanding of power networks is attracting attention, because of the increasing occurrence and risk of blackouts. Our proposed approach is quite flexible and incorporates line switching and load shedding. We also give the motivation behind the islanding operation and test our model on variety of test cases. The islanding model uses DC model of power flow equations. We give some of the shortcomings of this model and later improve this model by using piecewise linear approximation of nonlinear terms. The improved model yields good feasible results very quickly and numerical results on large networks show the promising performance of this model.

Presentació d'un nou model de "Trade-Off" d'estructura òptima de capital d'una empresa. La innovació consisteix a incloure una simplificació de la fórmula de distància a la fallida de Merton (1974) realitzada per Bystrom (2006), per a determinar la taxa d'interès de l'empresa. D'aquest mode s'inclou un efecte dinàmic del palanquejament sobre la taxa d'interès, la qual cosa afecta el cost del deute i la taxa de descompte utilitzada i que s'expressa com un increment o disminució de la probabilitat de fallida de l'empresa. A l'unir aquest resultat a la pèrdua i valor de bons "ferralla" (publicat per Altman & Suresh, 2007), s'obté l'actual valor net del cost de fallida que es manifesta com a percentatge del valor del deute. El model desenvolupat s'ha aplicat a les empreses que van integrar al 2007 el DJIA, que calcula nivells estimats de deute per a aquestes empreses entre l'any 1996 i l'any 2006. Posteriorment, el deute estimat s'acara amb el deute real de l'empresa amb l'ús de la prova estadística de Mann-Whitney. Els resultats obtinguts indiquen que el 63% de les companyies comparades no mostren una diferència estadísticament significativa entre el deute estimat i el real. / Presentamos un nuevo modelo de “Trade-Off” de estructura óptima de capital de una empresa. La innovación consiste en incluir una simplificación de la fórmula de distancia a la quiebra de Merton (1974) realizada por Bystrom (2006), para determinar la tasa de interés de la empresa. Así incluimos un efecto dinámico del apalancamiento sobre la tasa de interés, el cual afecta al coste de la deuda y a la tasa de descuento utilizada expresándose como un incremento o disminución de la probabilidad de quiebra de la empresa. Al unir este resultado a la perdida e valor de bonos “chatarra” (publicado por Altman & Suresh, 2007), obtenemos el valor presente neto del coste de quiebra expresado como porcentaje del valor de la deuda. El modelo desarrollado es aplicado a las empresas que integraron en el 2007 el DJIA, calculando niveles estimados de deuda para dichas empresas entre el año 1996 y el año 2006. La deuda estimada es luego comparada con la deuda real de la empresa utilizando la prueba estadística de Mann-Whitney. Los resultados obtenidos indican que el 63% de las compañías comparadas no muestran una diferencia estadísticamente significativa entre la deuda estimada y la real. / We introduce a new Trade-Off model of capital structure. the innovation introduced is a simplification of Merton's (1974) distance to bankruptcy done by Bystrom(2006), to calculate the company's interest rate. Thus we include a dynamic effect of leverage on the interest rate, which affects both the cost of debt and de discount rate of the model. when we add this to the discounted value of distressed bonds (published by Altman & Suresh, 2007), we get the net present value of the cost of bankruptcy as a percentage of the value of the debt. We applied the model to the companies in the DJIA in 2007, calculating estimated debt levels for each company between the years of 1996 and 2006. the estimated debt was then compared with the actual debt using the Mann-Whitney statistical test. The results indicated that, on 63% of the compared companies, there is no statistically significant difference between the estimated debt and the actual debt.

Background Children are influencing the family’s decision making process regarding food products. The children’s spending power is increasing and they become consumers in an early age. By influencing the parents, the children make them buy products that they had not planned to buy or make the parents avoid products that they usually would have bought. Online food shopping is increasing in Sweden and the home delivery grocery bag is the category of online food that has increased the most from 2010 to 2011. Familyfood Optima AB is one of the home delivery grocery bags companies that deliver grocery bags in the south of Sweden. Purpose The purpose of this thesis is to find how children affect their parents’ behavior of purchasing home delivery grocery bags. Method To understand how children affect their parents in the decision of home delivery grocery bags a qualitative approach was used where twelve semi-structured interviews were held. Seven of the interviews were held with customers to Familyfood Optima AB. Four interviews were held with non-customers that had been customers to Familyfood Optima AB and one interview was held with a respondent that never had been a customer of a home delivery grocery bag company. Conclusion Children are influencing their parents in the decision to purchase home delivery grocery bags. They also influence the parents in the decision of whether or not to continue purchasing the home delivery grocery bag. The decision of purchasing a home delivery grocery bag depends on the children’s influence and the extent of the parent’s yielding. To influence their parents, the child use both direct and indirect influence techniques and three of the five bases of power. The children’s influence is also dependent on the child’s age and the influence from peers.

Many real-life problems such as distributed meeting scheduling, mobile frequency allocation and resource allocation can be solved using multi-agent paradigms. Distributed constraint satisfaction problems (DisCSPs) is a framework for describing such problems in terms of related subproblems, called a complex local problem (CLP), which are dispersed over a number of locations, each with its own constraints on the values their variables can take. An agent knows the variables in its CLP plus the variables (and their current value) which are directly related to one of its own variables and the constraints relating them. It knows little about the rest of the problem. Thus, each CLP is solved by an agent which cooperates with other agents to solve the overall problem. Algorithms for solving DisCSPs can be classified as either systematic or local search with the former being complete and the latter incomplete. The algorithms generally assume that each agent has only one variable as they can solve DisCSP with CLPs using “virtual” agents. However, in large DisCSPs where it is appropriate to trade completeness off against timeliness, systematic search algorithms can be expensive when compared to local search algorithms which generally converge quicker to a solution (if a solution is found) when compared to systematic algorithms. A major drawback of local search algorithms is getting stuck at local optima. Significant researches have focused on heuristics which can be used in an attempt to either escape or avoid local optima. This thesis makes significant contributions to local search algorithms for DisCSPs. Firstly, we present a novel combination of heuristics in DynAPP (Dynamic Agent Prioritisation with Penalties), which is a distributed synchronous local search algorithm for solving DisCSPs having one variable per agent. DynAPP combines penalties on values and dynamic agent prioritisation heuristics to escape local optima. Secondly, we develop a divide and conquer approach that handles DisCSP with CLPs by exploiting the structure of the problem. The divide and conquer approach prioritises the finding of variable instantiations which satisfy the constraints between agents which are often more expensive to satisfy when compared to constraints within an agent. The approach also exploits concurrency and combines the following search strategies: (i) both systematic and local searches; (ii) both centralised and distributed searches; and (iii) a modified compilation strategy. We also present an algorithm that implements the divide and conquer approach in Multi-DCA (Divide and Conquer Algorithm for Agents with CLPs). DynAPP and Multi-DCA were evaluated on several benchmark problems and compared to the leading algorithms for DisCSPs and DisCSPs with CLPs respectively. The results show that at the region of difficult problems, combining search heuristics and exploiting problem structure in distributed constraint satisfaction achieve significant benefits (i.e. generally used less computational time and communication costs) over existing competing methods.

L'énergie est une ressource clé dans les systèmes commandés en réseau, en particulier dans les applications concernant les réseaux sans fil. Cette thèse étudie comment économiser l'énergie dans les capteurs sans fil avec une co-Conception contrôle et communication. Cette thèse examine les techniques et les approches existantes qui sont utilisées pour économiser l'énergie d'un point de vue de la communication et du contrôle. Cet étude est organisée selon une architecture de communication par couches couvrant de bas en haut les couches Physique, Liaison, Réseau, et Application. Puis, à partir de la conclusion que la puce radio est un important consommateur d'énergie, une loi conjointe de gestion des modes radio et de contrôle en boucle fermée est établie. La gestion des modes radio exploite les capacités de la puce radio à communter dans des modes de basses consommation pour économiser l'énergie, et d'adapter la puissance de transmission aux conditions du canal. Il en résulte un système de contrôle basé sur des événements où le système fonctionne en boucle ouverte à certains moments. Un compromis naturel apparaît entre l'économie d'énergie et les performances de contrôle. La loi conjointe est établie avec une formulation de contrôle optimal utilisant la Programmation Dynamique. Cette thèse résout le problème optimal dans les deux cas d'horizon infini et fini. La stabilité du système en boucle fermée est étudiée avec la formulation Input-To-State Stability (ISS). La principale conclusion de cette thèse, également illustrée dans la simulation, est que la conception à travers différentes couches dans les systèmes commandés en réseau est essentielle pour économiser l'énergie dans les noeuds sans fil. / Energy is a key resource in Networked Control Systems, in particular in applications concerning wireless networks. This thesis investigates how to save energy in wireless sensor nodes with control and communication co-Design. This thesis reviews existing techniques and approaches that are used to save energy from a communication and a control point of view. This review is organized according to the layered communication architecture covering from bottom to top the Physical, Data Link, Network, and Application layers. Then, from the conclusion that the radio chip is an important energy consumer, a joint radio-Mode management and feedback law policy is derived. The radio-Mode management exploits the capabilities of the radio chip to switch to low consuming radio-Modes to save energy, and to adapt the transmission power to the channel conditions. This results in an event-Based control scheme where the system runs open loop at certain time. A natural trade-Off appears between energy savings and control performance. The joint policy is derived in the framework of Optimal Control with the use of Dynamic Programming. This thesis solves the optimal problem in both infinite and finite horizon cases. Stability of the closed loop system is investigated with Input-To-State Stability framework. The main conclusion of this thesis, also shown in simulation, is that cross-Layer design in Networked Control System is essential to save energy in the wireless nodes.

This master thesis emphasizes the importance of aviation meteorological data for flight planning and for making inflight strategic decisions. It describes conventional ways of obtaining meteorological data before and during the flight. It provides the overview of alternative ways of acquiring weather related information. The master thesis compares how hazardous meteorological phenomena - thunderstorms, turbulence and icing - are displayed within the described commercial products.

[pt] As metodologias de projeto estrutural foram fortemente influenciadas pelo advento da computação. Os avanços nas áreas de análise numérica, como o método dos elementos finitos, e os softwares de Desenho Assistido por Computador, literalmente ajudaram a moldar o mundo como ele é hoje. Implementações computacionais das técnicas de otimização estrutural, como a otimização topológica, permitem a determinação das estruturas base, gerando uma grande quantidade de projetos novos, mais eficientes, com o potencial de mudar drasticamente o futuro das aeronaves, automóveis, edifícios, etc. Introduzir restrições de tensão na otimização topológica tradicional permite a obtenção de soluções mais seguras e confiáveis que se assemelhem mais à estrutura final. Contudo, isto não é uma tarefa trivial, apresentando várias dificuldades conceituais e numéricas. Nesta dissertação, as principais questões deste problema são discutidas e as técnicas presentes hoje na literatura são revisadas e criticadas quanto aos seus desempenhos. A principal contribuição deste trabalho é uma nova técnica baseada no Método do Lagrangiano Aumentado que lida eficientemente com um grande número de restrições. Em contraste com os métodos existentes, que são dependentes do problema e da malha, a abordagem proposta apresenta poucos parâmetros que precisam ser ajustados a cada novo caso. Para avaliar suas potencialidades, desenvolveu-se um código em MATLAB, eficaz e robusto. Diversos exemplos representativos, incluindo problemas de larga escala, são apresentados. Finalmente, as soluções obtidas, incluindo algumas complicações inesperadas, são discutidas detalhadamente e sugestões para trabalhos futuros são propostas. / [en] Structural design methodologies were strongly influenced by the advent of computing. The advances in numerical analyses, such as the finite element method, and Computer Aided Design software have literally helped shape the engineering world as it is today. Structural optimization methods such as topology optimization aim to take the next step by letting the computer guide the design, in order to achieve new and more eficient designs. This approach has the potential to change the future of various industries, including aircraft, automobile, construction, etc. The introduction of stress constraints on traditional topology optimization allows for safer and more reliable solutions that will more closely resemble the final structure. The successful solution of this problem poses several conceptual and numerical dificulties. Thus this dissertation details the main issues of this problem and reviews the current techniques discussed in the literature including some critiques of their performance. The main contribution of this work is a novel technique based on the Augmented Lagrangian method that can eficiently handle a large number of constraints. In contrast to existing methods which are both problem- and mesh-dependent, the presented approach contains only a few parameters which need to be adjusted for each new case. In order to verify the technique s capabilities, a user friendly MATLAB code was developed that is both effective and robust. Several representative examples, including large-scale problems, are presented. Finally, the solutions obtained here, including some unexpected complications, are thoroughly discussed and suggestions for future work are also addressed.