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This work extends recent research in the development of a number of direct search methods in nonlinear integer programming. The various algorithms use an extension of the well-known FORTRAN MINOS code of Murtagh and Saunders as a starting point. MINOS is capable of solving quite large problems in which the objective function is nonlinear and the constraints linear. The original MINOS code has been extended in various ways by Murtagh, Saunders and co-workers since the original 1978 landmark paper. Extensions have dealt with methods to handle both nonlinear constraints, most notably MINOS/AUGMENTED and integer requirements on a subset of the variables(MINTO). The starting point for the present thesis is the MINTO code of Murtagh. MINTO is a direct descendant of MINOS in that it extends the capabilities to general nonlinear constraints and integer restrictions. The overriding goal for the work described in this thesis is to obtain a good integer-feasible or near-integer-feasible solution to the general NLIP problem while trying to avoid or at least minimize the use of the ubiquitous branch-and-bound techniques. In general, we assume a small number of nonlinearities and a small number of integer variables.Some initial ideas motivating the present work are summarised in an invited paper presented by Murtagh at the 1989 CTAC (Computational Techniques and Applications) conference in Brisbane, Australia. The approach discussed there was to start a direct search procedure at the solution of the continuous relaxation of a nonlinear mixed-integer problem by first removing integer variables from the simplex basis, then adjusting integer-infeasible superbasic variables, and finally checking for local optimality by trial unit steps in the integers. This may be followed by a reoptimization with the latest point as the starting point, but integer variables held fixed. We describe ideas for the further development of Murtagh’s direct search method. Both the old and new approaches aim to attain an integer-feasible solution from an initially relaxed (continuous) solution. Techniques such as branch-and-bound or Scarf’s neighbourhood search [84] may then be used to obtain a locally optimal solution. The present range of direct search methods differs significantly to that described by Murtagh, both in heuristics used and major and minor steps of the procedures. Chapter 5 summarizes Murtagh’s original approach while Chapter 6 describes the new methods in detail.Afeature of the new approach is that some degree of user-interaction (MINTO/INTERACTIVE) has been provided, so that a skilled user can "drive" the solution towards optimality if this is desired. Alternatively the code can still be run in "automatic" mode, where one of five available direct search methods may be specified in the customary SPECS file. A selection of nonlinear integer programming problems taken from the literature has been solved and the results are presented here in the latter chapters. Further, anewcommunications network topology and allocation model devised by Berry and Sugden has been successfully solved by the direct search methods presented herein. The results are discussed in Chapter 14, where the approach is compared with the branch-and-bound heuristic.

This work extends recent research in the development of a number of direct search methods in nonlinear integer programming. The various algorithms use an extension of the well-known FORTRAN MINOS code of Murtagh and Saunders as a starting point. MINOS is capable of solving quite large problems in which the objective function is nonlinear and the constraints linear. The original MINOS code has been extended in various ways by Murtagh, Saunders and co-workers since the original 1978 landmark paper. Extensions have dealt with methods to handle both nonlinear constraints, most notably MINOS/AUGMENTED and integer requirements on a subset of the variables(MINTO). The starting point for the present thesis is the MINTO code of Murtagh. MINTO is a direct descendant of MINOS in that it extends the capabilities to general nonlinear constraints and integer restrictions. The overriding goal for the work described in this thesis is to obtain a good integer-feasible or near-integer-feasible solution to the general NLIP problem while trying to avoid or at least minimize the use of the ubiquitous branch-and-bound techniques. In general, we assume a small number of nonlinearities and a small number of integer variables.Some initial ideas motivating the present work are summarised in an invited paper presented by Murtagh at the 1989 CTAC (Computational Techniques and Applications) conference in Brisbane, Australia. The approach discussed there was to start a direct search procedure at the solution of the continuous relaxation of a nonlinear mixed-integer problem by first removing integer variables from the simplex basis, then adjusting integer-infeasible superbasic variables, and finally checking for local optimality by trial unit steps in the integers. This may be followed by a reoptimization with the latest point as the starting point, but integer variables held fixed. We describe ideas for the further development of Murtagh’s direct search method. Both the old and new approaches aim to attain an integer-feasible solution from an initially relaxed (continuous) solution. Techniques such as branch-and-bound or Scarf’s neighbourhood search [84] may then be used to obtain a locally optimal solution. The present range of direct search methods differs significantly to that described by Murtagh, both in heuristics used and major and minor steps of the procedures. Chapter 5 summarizes Murtagh’s original approach while Chapter 6 describes the new methods in detail.Afeature of the new approach is that some degree of user-interaction (MINTO/INTERACTIVE) has been provided, so that a skilled user can "drive" the solution towards optimality if this is desired. Alternatively the code can still be run in "automatic" mode, where one of five available direct search methods may be specified in the customary SPECS file. A selection of nonlinear integer programming problems taken from the literature has been solved and the results are presented here in the latter chapters. Further, anewcommunications network topology and allocation model devised by Berry and Sugden has been successfully solved by the direct search methods presented herein. The results are discussed in Chapter 14, where the approach is compared with the branch-and-bound heuristic.

Šiame darbe kuriamas įrankis, kuris padėtų nustatyti, kurios morfologinės žymos savybės yra svarbios sprendžiant lietuvių kalbos morfologinio daugiareikšmiškumo problemą. Morfologinio daugiareikšmiškumo problema išsprendžiama tuomet, kai pagal kontekstą vienam žodžiui priskiriama viena morfologinė žyma. Darbe naudojamas tekstynas, kurį sudaro daugiau nei 1.200.000 žodžių. Tekstyne žodžiams morfologines žymas nustatė ekspertas, o visos galimos žodžio morfologinės žymos buvo sugeneruotos su pagalbiniu įrankiu. Morfologinio daugiareikšmiškumo problemoms spręsti suprogramuotas ir taikytas Viterbi algoritmas, randantis tikėtiniausią sakinį atitinkančią kalbos dalių seką pagal sukurtus bigramų ar trigramų kalbos modelius. Atlikus testavimą naudojant dešimt kartų kryžminį patikrinimą, pasiekti toki rezultatai: • 90,10% – tikslumas, kuris parodo ar teisingai priskirta morfologinė žyma daugiareikšmiams žodžiams; • 96,39% – bendras tikslumas, kuris skaičiuojamas įtraukiant ir tuos žodžius, kurie turėjo tik vieną morfologinę žymą. / In this research was developed tool, which helps to determine, which morphological mark attributes are important when solving problem of morphological ambiguity in Lithuanian language. Morphological ambiguity problem is solved, when one word is matched with one morphological mark. Research uses corpus, which contains over than 1.200.000 words. Morphological marks in the corpus were assigned by expert and list of all possible morphological marks was generated with other utility. There was developed and applied Viterbi algorithm to solve morphological ambiguity problem, which finds the most expected path of part of speeches by created bigram or trigram speech models. Testing was implemented using cross validation with 10 folds. There was achieved these results: • 90,10% – accuracy, which shows if morphological mark was correctly match with ambiguous word; • 96,39% – total accuracy, which calculated when included non-ambiguous words.

Šio bakalauro darbo tikslas - realizuoti tiesioginės paieškos metodą (lyderio ir pasekėjo uždaviniui). Šiam tikslui pasiekti buvo nagrinėjama tiesioginio paieškos metodo (lyderio ir pasekėjo uždaviniui) matematinė formuluotė ir algoritmas pateikti Dali Zhang ir Gui-Hua Lin darbe„Dviejų lygių tiesioginės paieškos metodas lyderio – pasekėjo uždaviniui ir taikymams“ (angl. „Bilevel Direct Search Method for Leader – Follower Equilibrium Problems and Applications“). Darbo metu buvo sukurta programa, realizuojanti metodą, metodas pritaikytas oligopolinės rinkos modeliui (deterministiniam, nedeterministiniam, stochastiniam) spręsti, taip pat metodas pritaikytas oligopolinės rinkos modeliui, kai algoritmo parametrai generuojami atsitiktinai. / The purpose of this bachelor work – to realize the Direct Search Method (for Leader - Follower problem). To achieve this aim was analyzed the mathematical formulation of direct search method and algorithm that were submitted at paper of Dali Zhang and Gui-Hua Lin „Bilevel Direct Search Method for Leader – Follower Equilibrium Problems and Applications“. During this work was developed a program for realizing the method. The method was adapted for oligopolistic market model (deterministic, non-deterministic, stochastic), also, method was adapted for oligopolistic market model, when the parameters of algorithm are generated randomly.

Made available in DSpace on 2015-04-11T14:02:37Z (GMT). No. of bitstreams: 1 Aurelio Menezes.pdf: 945467 bytes, checksum: 1703733b16c0af4b0b95b32aa95aa34e (MD5) Previous issue date: 2012-08-22 / Large databases have been very common nowadays. These databases allow access to a huge amount of information. However, this scenario leads the task of finding a specific information among such a large amount of information, become very difficult. Systems of Information Retrieval (IR) have been widely used to sole this kind of problem. Among the many problems caused by the large amount of information available on databases, there is the problem related to competence searching. This problem occurs in the following context, given a profile, described as a set of competencies, one looks for finding researchers with similar profiles. In this work, we describe an IR method which provides support to find researchers taking into account competence information retrieved from a database a desired competency profile, the proposed method provides the curriculums more similar to the desired profile. The experiments were conducted using three proposed strategies: Sum of Similarities, Production and Borda Count. The results achieved show that the proposed successfully accomplishes its objective / Grandes bases de dados tem sido muito comum hoje em dia e tem permitido o acesso a uma grande quantidade de informação. Por outro lado, esse cenário torna dificil a tarefa de encontrar uma informação específica no meio de uma grande quantidade de informação. Sistemas de Recuperação de Informação (RI) têm sido largamente empregados para a solucionar este tipo de problema. Dentre os problemas ocasionados pela grande quantidade de informação disponível em bases de dados, existe o problema da busca de competências. Este problema ocorre no seguinte contexto, dado um perfil, descrito na forma de um conjunto de competências, procura-se descobrir pesquisadores com perfis similares. Este trabalho descreve um método de RI que fornece apoio à busca de pesquisadores a partir de informações sobre competências extraídas de uma base de currículos Lattes. Assim, dada uma consulta especificando um perfil de competência desejada, são selecionados os currículos com maior grau de similaridade com este perfil. Após a execução de experimentos em três estratégias propostas: Soma de Similaridades, Produção e Contagem de Borda, os resultados indicam o sucesso do método proposto

Today's modern aerospace systems exhibit strong interdisciplinary coupling and require a multidisciplinary, collaborative approach. Analysis methods that were once considered feasible only for advanced and detailed design are now available and even practical at the conceptual design stage. This changing philosophy for conducting conceptual design poses additional challenges beyond those encountered in a low fidelity design of aircraft. This thesis takes some steps towards bridging the gaps in existing technologies and advancing the state-of-the-art in aircraft design. The first part of the thesis proposes a new Pareto front approximation method for multiobjective optimization problems. The method employs a hybrid optimization approach using two derivative free direct search techniques, and is intended for solving blackbox simulation based multiobjective optimization problems with possibly nonsmooth functions where the analytical form of the objectives is not known and/or the evaluation of the objective function(s) is very expensive (very common in multidisciplinary design optimization). A new adaptive weighting scheme is proposed to convert a multiobjective optimization problem to a single objective optimization problem. Results show that the method achieves an arbitrarily close approximation to the Pareto front with a good collection of well-distributed nondominated points. The second part deals with the interdisciplinary data communication issues involved in a collaborative mutidisciplinary aircraft design environment. Efficient transfer, sharing, and manipulation of design and analysis data in a collaborative environment demands a formal structured representation of data. XML, a W3C recommendation, is one such standard concomitant with a number of powerful capabilities that alleviate interoperability issues. A compact, generic, and comprehensive XML schema for an aircraft design markup language (ADML) is proposed here to provide a common language for data communication, and to improve efficiency and productivity within a multidisciplinary, collaborative environment. An important feature of the proposed schema is the very expressive and efficient low level schemata. As a proof of concept the schema is used to encode an entire Convair B58. As the complexity of models and number of disciplines increases, the reduction in effort to exchange data models and analysis results in ADML also increases. / Ph. D.

Bakgrund: Den tilltagande oron för vår planets välmående har medfört ett ökat samhällsfokus på hållbar utveckling. Det är av vikt att företag engagerar sig i hållbar utveckling delvis eftersom de orsakar många hållbarhetsrelaterade problem, och delvis eftersom de har de resurser som krävs för att lösa problemen. För att påverka hållbar utveckling behöver företag driva fram hållbara innovationer för att förändra deras produkter, processer och affärsmodeller. Forskningsfältet gällande hållbara innovationer är dock i en initial uppbyggnadsfas, och därmed behövs fler studier. Framförallt är forskningsområdet i behov av fler kvalitativa studier som belyser hur hållbara innovationer utvecklas på företagsnivå. Syfte: Syftet med uppsatsen är att öka förståelsen för hur hållbarhet införlivas i företags innovationsprocesser. Metod: En kvalitativ studie med åtta respondenter fördelade över sju semistrukturerade intervjuer. Slutsatser: Studien visar på tre faktorer som behövs för att skapa en organisationskultur där lärande uppmuntras. De tre faktorerna är hållbarhetsramverk, tillit till anställdas förmåga samt frihet i att utforma arbetsprocesser. Tillsammans leder faktorerna till att skapa en lärande kultur som driver införlivande av hållbarhet i innovationsprocessen. Studien visar också att tvärfunktionella grupper behöver skapas i de initiala faserna av innovationsprocessen. De tvärfunktionella grupperna bör tillåtas inneha ett explorativt idésökande som arbetssätt. Det explorativa sökandet efter innovationer kan ske internt inom företagen eller genom externa samarbeten. / Background: The increasing concern for our planet’s well-being has induced an increased focus on sustainable development. It is of importance for companies to engage in sustainable development, partly since they are the reason for many sustainability-related issues, and partly because they have the resources required to solve the issues. In order to affect sustainable development, companies need to develop sustainable innovations to change their products, processes and business models. However, the research field concerning sustainable innovations is still in its infancy stage and therefore requires more research. In particular, the research field is in need of more qualitative research which refers to how sustainable innovations are developed on a company level. Purpose: The aim of this study is to increase the understanding of how sustainability can be incorporated into the innovation process. Method: A qualitative study with eight respondents distributed across seven semi-structured interviews. Findings: The study points out three factors that are essential when creating an organizational culture which encourage learning. The three factors are sustainable framework, trust in the employees’ abilities and lastly freedom for employees to form their work processes. Together the factors create a learning culture that drives the incorporation of sustainability into the innovation process. The study also pinpoints the need of creating cross-functional groups in the initial phases of the innovation process. The cross-functional teams should be encouraged to use an exploratory search method. An exploratory search for innovation can be conducted within the corporation or through external collaborations.

This research encompasses the automated design and structural optimization of reinforced concrete slab frame bridges, considering investment costs and environmental impacts. The most important feature of this work is that it focusses on realistic and complete models of slab frame bridges rather than on optimization of only individual members or sections of a bridge. The thesis consists of an extended summary of publications and three appended papers. In the first paper, using simple assumptions, the possibility of applying cost-optimization to the structural design of slab frame bridges was investigated. The results of the optimization of an existing constructed bridge showed the potential to reduce the investment cost of slab frame bridges. The procedure was further developed in the second paper. In this paper, automated design was integrated to a more refined cost-optimization methodology based on more detailed assumptions and including extra constructability factors. This procedure was then applied to a bridge under design, before its construction. From the point of view of sustainability, bridge design should not only consider criteria such as cost but also environmental performance. The third paper thus integrated life cycle assessment (LCA) with the design optimization procedure to perform environmental impact optimization of the same case study bridge as in the second paper. The results of investment cost and environmental impact optimization were then compared. The obtained results presented in the appended papers highlight the successful application of optimization techniques to the structural design of reinforced concrete slab frame bridges. Moreover, the results indicate that a multi-objective optimization that simultaneously considers both environmental impacts and investment cost is necessary in order to generate more sustainable designs. The presented methodology has been applied to the design process for a time-effective, sustainable, and optimal design of concrete slab frame bridges. / <p>QC 20170316</p>

O presente trabalho apresenta a identificação de parâmetros de motor de indução linear tubular para a extração de petróleo, denominado de MATÆOS -- Motor Assíncrono Tubular para Aplicação na Extração de Óleo Subterrâneo. O primeiro passo para a identificação de parâmetros do motor foi a implementação da bancada de testes com o seu sistema de controle e supervisório. O modelo adotado corresponde à situação de operação em regime estacionário e consiste no circuito contendo resistores e indutores tradicionalmente utilizado para representar motores de indução. A identificação dos parâmetros foi realizada por meio de um procedimento de otimização tomando por base o balanço de potência do motor. Para isso, em função dos parâmetros do modelo, definiu-se e minimizou-se uma medida de erro entre as potências medidas e as calculadas pelo modelo para um conjunto pré-fixado de escorregamentos. A solução desse problema de otimização foi obtida por meio de uma busca exaustiva, uma vez que o número de variáveis independentes do problema é pequeno e uma região contendo o ponto de mínimo é conhecida com razoável confiança. Os resultados obtidos indicam que os valores dos parâmetros nominais a quente apresentam algumas diferenças em relação àqueles produzidos pelo método de identificação. Essas diferenças se devem possivelmente a variações nas características térmicas do motor e a erros introduzidos pelos instrumentos de medida. O modelo identificado apresentou uma menor disponibilidade de força e um pior rendimento quando comparado com os valores de projeto do modelo nominal a quente. Apesar disto, verificou-se uma boa proximidade entre a curva característica do modelo e as obtidas experimentalmente. / This work presents the identification of parameters of the tubular linear induction motor for the extraction of oil, called MATÆOS - which is the Portuguese acronym for Asynchronous Tubular Motor for Application to Subterranean Oil Extraction. The first step to the identification of the motor parameters was the implementation of the supervisory and control system for the test bench. The model, which is the usual one containing resistors and inductors, represents the motor operating in steady-state. The parameter identification problem was written as an optimization problem based on the motor power balance. An error between the measured power and the one given by the model was defined and minimized with respect to the model parameters in correspondence to a given set of slipping frequencies. The numerical solution to this problem was obtained by an exhaustive search algorithm. This choice was made because the number of independent variables is small and a region containing the solution is known with a significant degree of confidence. The results obtained show that the nominal values of the model parameters differ slightly from those produced by the identification method. Possibly, such differences are due to the variations in the model caused by temperature changes and to the measurement errors. The identified model presented both a lower available force and a worst efficiency when compared to the nominal design values for the warm motor. Despite this the characteristic curve of the model was quite close to the nominal design one.