On optimal location with treshold requirements

The optimal location of services is one of the most important factors that affects service quality in terms of consumer access. On theother hand, services in general need to have a minimum catchment area so as to be efficient. In this paper a model is presented that locates the maximum number of services that can coexist in a given region without having losses, taking into account that they need a minimum catchment area to exist. The objective is to minimize average distance to the population. The formulation presented belongs to the class of discrete P--median--like models. A tabu heuristic method is presented to solve the problem. Finally, the model is applied to the location of pharmacies in a rural region of Spain.

Supermarket key attributes and location decisions: A comparative study between British and Spanish consumers

The Maximum Capture problem (MAXCAP) is a decision model that addresses the issue of location in a competitive environment. This paper presents a new approach to determine which store s attributes (other than distance) should be included in the newMarket Capture Models and how they ought to be reflected using the Multiplicative Competitive Interaction model. The methodology involves the design and development of a survey; and the application of factor analysis and ordinary least squares. Themethodology has been applied to the supermarket sector in two different scenarios: Milton Keynes (Great Britain) and Barcelona (Spain).

Location of hubs in a competitive environment

We offer a formulation that locates hubs on a network in a competitiveenvironment; that is, customer capture is sought, which happenswhenever the location of a new hub results in a reduction of thecurrent cost (time, distance) needed by the traffic that goes from thespecified origin to the specified destination.The formulation presented here reduces the number of variables andconstraints as compared to existing covering models. This model issuited for both air passenger and cargo transportation.In this model, each origin-destination flow can go through either oneor two hubs, and each demand point can be assigned to more than a hub,depending on the different destinations of its traffic. Links(``spokes'' have no capacity limit. Computational experience is provided.

On certain greedoid polyhedra, partially indexable scheduling problems and extended restless bandit allocation indices

We present a polyhedral framework for establishing general structural properties on optimal solutions of stochastic scheduling problems, where multiple job classes vie for service resources: the existence of an optimal priority policy in a given family, characterized by a greedoid(whose feasible class subsets may receive higher priority), where optimal priorities are determined by class-ranking indices, under restricted linear performance objectives (partial indexability). This framework extends that of Bertsimas and Niño-Mora (1996), which explained the optimality of priority-index policies under all linear objectives (general indexability). We show that, if performance measures satisfy partial conservation laws (with respect to the greedoid), which extend previous generalized conservation laws, then theproblem admits a strong LP relaxation over a so-called extended greedoid polytope, which has strong structural and algorithmic properties. We present an adaptive-greedy algorithm (which extends Klimov's) taking as input the linear objective coefficients, which (1) determines whether the optimal LP solution is achievable by a policy in the given family; and (2) if so, computes a set of class-ranking indices that characterize optimal priority policies in the family. In the special case of project scheduling, we show that, under additional conditions, the optimal indices can be computed separately for each project (index decomposition). We further apply the framework to the important restless bandit model (two-action Markov decision chains), obtaining new index policies, that extend Whittle's (1988), and simple sufficient conditions for their validity. These results highlight the power of polyhedral methods (the so-called achievable region approach) in dynamic and stochastic optimization.

Planeamento de Experiências: Modelos e desafios dos Planos em Blocos Incompletos

O principal objetivo de um Planeamento de Experiências reside essencialmente na procura de relações entre variáveis e na comparação de níveis de fatores, recorrendo ao tratamento estatístico dos dados recolhidos. A utilização de blocos no Planeamento de Experiências é fundamental, pois permite reduzir ou eliminar a variabilidade introduzida por fatores que podem influenciar a experiência mas que não interessam e/ou não foram explicitamente incluídos durante o planeamento. Neste trabalho apresentamos os resultados do estudo e investigação dos Planos em Blocos Incompletos Equilibrados (BIBD), Planos em Blocos Incompletos Equilibrados com repetição de blocos (BIBDR) e Planos em Blocos Incompletos com blocos de diferentes dimensões (VBBD). Exploramos algumas propriedades e métodos de construção destes planos e ilustramos, sempre que possível, com exemplos. Tendo como base o planeamento em blocos, apresentamos uma aplicação dos BIBDR na área da Educação com o objetivo de comparar cinco domínios do pensamento algébrico de uma amostra de alunos do 1º ano do ensino superior em Cabo Verde. Para a análise dos dados da amostra foi utilizado o software R, versão 2.12.1. Pudemos constatar que existem diferenças significativas entre alguns dos domínios do pensamento algébrico, nomeadamente entre os domínios da Generalização da Aritmética e Tecnicismo Algébrico com os restantes domínios. Recomendamos a escolha de uma amostra mais representativa constituída por alunos de todas as instituições superiores de Cabo Verde.

Locating emergency services with different priorities: The priority queuing covering location problem

Previous covering models for emergency service consider all the calls to be of the sameimportance and impose the same waiting time constraints independently of the service's priority.This type of constraint is clearly inappropriate in many contexts. For example, in urban medicalemergency services, calls that involve danger to human life deserve higher priority over calls formore routine incidents. A realistic model in such a context should allow prioritizing the calls forservice.In this paper a covering model which considers different priority levels is formulated andsolved. The model heritages its formulation from previous research on Maximum CoverageModels and incorporates results from Queuing Theory, in particular Priority Queuing. Theadditional complexity incorporated in the model justifies the use of a heuristic procedure.

Population based resource allocation: The use of hybrid risk adjustment

The emphasis on integrated care implies new incentives that promote coordinationbetween levels of care. Considering a population as a whole, the resource allocation systemhas to adapt to this environment. This research is aimed to design a model that allows formorbidity related prospective and concurrent capitation payment. The model can be applied inpublicly funded health systems and managed competition settings.Methods: We analyze the application of hybrid risk adjustment versus either prospective orconcurrent risk adjustment formulae in the context of funding total health expenditures for thepopulation of an integrated healthcare delivery organization in Catalonia during years 2004 and2005.Results: The hybrid model reimburses integrated care organizations avoiding excessive risktransfer and maximizing incentives for efficiency in the provision. At the same time, it eliminatesincentives for risk selection for a specific set of high risk individuals through the use ofconcurrent reimbursement in order to assure a proper classification of patients.Conclusion: Prospective Risk Adjustment is used to transfer the financial risk to the healthprovider and therefore provide incentives for efficiency. Within the context of a National HealthSystem, such transfer of financial risk is illusory, and the government has to cover the deficits.Hybrid risk adjustment is useful to provide the right combination of incentive for efficiency andappropriate level of risk transfer for integrated care organizations.

Planeamento de experiências : modelos e desafios dos planos em blocos incompletos

The main purpose of an Experimental Design resides mainly in the search for relationships between variables and in comparing levels of factors, using statistical treatment of collected data. The use of blocks in Experimental Design is essential because it allows reducing or eliminating the variability introduced by factors that can influence the experience but are not of main interest and/or were not explicitly included during experiments. In this work we present the results of the study and research of Balanced Incomplete Block Designs (BIBD), Balanced Incomplete Block Designs with repeated blocks (BIBDR) and the Incomplete Blocks Designs with blocks with different dimensions (VBBD). We explore some properties and construction methods of such designs and illustrate, when possible, with examples. Based on Block Designs, we present an application of BIBDR in Education, with the aim of comparing five domains of algebraic thinking in a sample of 1st year students of higher education in Cape Verde. For the analysis of sample data, the software R was used, version 2.12.1. We observed that significant differences exist between some of the domains of algebraic thinking, especially among the domains of Generalization of Arithmetic and Algebraic Technicality with the remaining areas. For a more representative sample, we recommend a bigger sample consisting of students from all higher institutions of Cape Verde.

TREINO NÃO SUPERVISIONADO DE MODELOS ACÚSTICOS PARA RECONHECIMENTO DE FALA

Esta tese resume os trabalhos desenvolvidos na área de processamento automático de fala com o objetivo de incrementar a quantidade de recursos linguísticos disponíveis para o português europeu. O estágio de desenvolvimento e a aplicação das tecnologias de fala para uma língua estão relacionados com a quantidade e a qualidade de recursos disponíveis para esta língua. Poucas línguas apresentam, no domínio público e livre, todos os recursos necessários para desenvolver as tecnologias de fala. A língua portuguesa, como muitas outras, tem escassez de recursos públicos e livres, o que pode dificultar o desenvolvimento e a aplicação de tecnologias de fala que incorporam esta língua. Os trabalhos descritos nesta tese apresentam uma abordagem para criar bases de dados de fala, recorrendo apenas aos recursos do domínio público e livres, partindo de sinais multimédia sem transcrições ortográficas ou fonéticas. É apresentada uma solução para aproveitar a grande disponibilidade de material multimédia existente no domínio público (podcasts por exemplo) e selecionar segmentos de fala adequados para treinar modelos acústicos. Para isso, foram desenvolvidos vários sistemas para segmentar e classificar automaticamente os noticiários. Estes sistemas podem ser combinados para criar bases de dados de fala com transcrição fonética sem a intervenção humana. Foi desenvolvido um sistema de conversão automático de grafemas para fonemas que se apoia em regras fonológicas e modelos estatísticos. Esta abordagem híbrida é justificada pelos desenvolvimentos de algoritmos de aprendizagem automática aplicados a conversão de grafemas para fonemas e pelo fato do português apresentar uma razoável regularidade fonética e fonológica bem como uma ortografia de base fonológica. Com auxílio deste sistema, foi criado um dicionário de pronunciação com cerca de 40 mil entradas, que foram verificadas manualmente. Foram implementados sistemas de segmentação e de diarização de locutor para segmentar sinais de áudio. Estes sistemas utilizam várias técnicas como a impressão digital acústica, modelos com misturas de gaussianas e critério de informação bayesiana que normalmente são aplicadas noutras tarefas de processamento de fala. Para selecionar os segmentos adequados ou descartar os segmentos com fala não preparada que podem prejudicar o treino de modelos acústicos, foi desenvolvido um sistema de deteção de estilos de fala. A deteção de estilos de fala baseia-se na combinação de parâmetros acústicos e parâmetros prosódicos, na segmentação automática e em classificadores de máquinas de vetores de suporte. Ainda neste âmbito, fez-se um estudo com o intuito de caracterizar os eventos de hesitações presentes nos noticiários em português. A transcrição fonética da base de dados de fala é indispensável no processo de treino de modelos acústicos. É frequente recorrer a sistemas de reconhecimento de fala de grande vocabulário para fazer transcrição automática quando a base de dados não apresenta nenhuma transcrição. Nesta tese, é proposto um sistema de word-spotting para fazer a transcrição fonética dos segmentos de fala. Fez-se uma implementação preliminar de um sistema de word-spotting baseado em modelos de fonemas. Foi proposta uma estratégia para diminuir o tempo de resposta do sistema, criando, a priori, uma espécie de “assinatura acústica” para cada sinal de áudio com os valores de todos os cálculos que não dependem da palavra a pesquisar, como a verosimilhanças de todos os estados dos modelos de fonemas. A deteção de uma palavra utiliza medidas de similaridade entre as verosimilhanças do modelo da palavra e do modelo de enchimento, um detetor de picos e um limiar definido por forma a minimizar os erros de deteção. Foram publicados vários recursos para a língua portuguesa que resultaram da aplicação dos vários sistemas desenvolvidos ao longo da execução desta tese com especial destaque para o sistema de conversão de grafemas para fonemas a partir do qual se publicaram vários dicionários de pronunciação, dicionários com as palavras homógrafas heterofónicas, dicionário com estrangeirismos, modelos estatísticos para a conversão de grafemas para fonemas, o código fonte de todo sistema de treino e conversão e um demonstrador online.

Sistemas da qualidade no ensino superior : contributos para modelos de melhoria da qualidade e responsabilidade social

A gestão das Instituições de Ensino Superior está a ser repensada num contexto de globalização tendo em conta a missão destas, a responsabilidade e a sua cultura (ou culturas), impondo-se novos modelos de gestão e governação. A Qualidade e a Responsabilidade Social do Ensino Superior constituem um tema pertinente e actual. As transformações estruturais que as sociedades atravessam aconselham e justificam da parte do Ensino Superior uma atitude consentânea com as necessidades daquelas. Os desafios que, as Instituições de Ensino Superior enfrentam, exigem novas perspectivas estratégicas e nova visão perante cenários de incerteza que surgem a nível mundial, desempenhando a liderança um papel fundamental na qualidade destas instituições. Neste sentido, lança-se no presente estudo, a seguinte questão: Que Modelos de Gestão e Governação contribuem para a melhoria da Qualidade no Ensino Superior? A metodologia utilizada para a realização deste estudo passa pelo delineamento de uma estratégia com cinco fases: elaboração de um plano ajustável à evolução do trabalho, levantamento do estado da arte de uma forma gradual, trabalho de pesquisa e criação, escrita da tese e análise crítica e reflexão. Para além de outros aspectos relevantes no domínio do Ensino Superior, foram estudados diversos modelos, Modelos de Excelência, modelos para implementação de Sistemas de Gestão da Qualidade, Gestão Ambiental, Gestão da Segurança e Saúde do Trabalho, Gestão de Risco; entre outros. Criaram-se diversos Indicadores de Responsabilidade Social neste contexto e foi feito um estudo piloto no âmbito da Responsabilidade Social em Instituições de Ensino Superior. Por último, destacaram-se as conclusões que decorrem do estudo piloto efectuado, bem como reflexões que surgem da investigação teórica realizada. O estudo piloto efectuado permitiu concluir, por exemplo, que existem indícios de algum alheamento no seio das Instituições às temáticas relacionadas com os princípios éticos e com a educação ambiental. Por outro lado, uma grande parte dos indivíduos inquiridos disseram não ter qualquer opinião quando confrontados com questões sobre Participação Social Responsável, Investigação Socialmente Útil e Gestão Social do Conhecimento. Conclui-se que as questões para as pessoas ainda são muito vagas, daí que, faça sentido o debate de todas estas questões, bem como estudos que contribuam para uma mudança de paradigma relativamente à educação, e em particular no Ensino Superior, com vista à qualidade, num sentido abrangente.

Sistemas da qualidade no ensino superior : contributos para modelos de melhoria da qualidade e responsabilidade social

The management of Higher Education Institutions is being rethought, with the mission and culture of the institutions changing due to globalization, resulting in new models of management and governance. The quality of Higher Education and its obligations to society are of current importance. The structural changes that the society has gone through requires a response in higher education that matches the changing needs of the society. Higher Education Institutions require new perspectives and a new strategic vision to cope with the uncertainty arising at a global scale, and this plays a role in their quality and whether they are leading institutions. Thus the following question arises: Which forms of management and governance contribute to the improvement of quality in higher education? The methodology for this study was designed with five stages: preparation of a plan of work within the thesis, the gradual progression to understanding the up-to-date understanding of Higher Education Research, generating research hypotheses and creating further understanding, writing the thesis with critical analysis and reflection. In addition to other relevant issues in higher education, different models were studied: Models of excellence, Models for implementation of Quality Management Systems, Environmental Management, Occupational Health and Safety Management, Risk Management, among others. Several indicators of Social Responsibility were created in this context and a pilot study was conducted in the area of Social Responsibility in Higher Education Institutions. Finally the conclusions resulting from the pilot study are presented and questions arising from the theoretical research are discussed. For example, the pilot study showed that there are indicators of a lack of understanding within the institutions to issues related to ethical and environmental education. Moreover, a large proportion of respondents said individuals have no opinion when confronted with questions on Responsible Social Involvement and Social Research and Social Management of Useful Knowledge. It is concluded that people have a vague awareness of these issues, so these concepts are new to them.

Sistemas da qualidade no ensino superior : contributos para modelos de melhoria da qualidade e responsabilidade social

The management of Higher Education Institutions is being rethought, with the mission and culture of the institutions changing due to globalization, resulting in new models of management and governance. The quality of Higher Education and its obligations to society are of current importance. The structural changes that the society has gone through requires a response in higher education that matches the changing needs of the society. Higher Education Institutions require new perspectives and a new strategic vision to cope with the uncertainty arising at a global scale, and this plays a role in their quality and whether they are leading institutions. Thus the following question arises: Which forms of management and governance contribute to the improvement of quality in higher education? The methodology for this study was designed with five stages: preparation of a plan of work within the thesis, the gradual progression to understanding the up-to-date understanding of Higher Education Research, generating research hypotheses and creating further understanding, writing the thesis with critical analysis and reflection. In addition to other relevant issues in higher education, different models were studied: Models of excellence, Models for implementation of Quality Management Systems, Environmental Management, Occupational Health and Safety Management, Risk Management, among others. Several indicators of Social Responsibility were created in this context and a pilot study was conducted in the area of Social Responsibility in Higher Education Institutions. Finally the conclusions resulting from the pilot study are presented and questions arising from the theoretical research are discussed. For example, the pilot study showed that there are indicators of a lack of understanding within the institutions to issues related to ethical and environmental education. Moreover, a large proportion of respondents said individuals have no opinion when confronted with questions on Responsible Social Involvement and Social Research and Social Management of Useful Knowledge. It is concluded that people have a vague awareness of these issues, so these concepts are new to them.

Sistemas da qualidade no ensino superior : contributos para modelos de melhoria da qualidade e responsabilidade social

The management of Higher Education Institutions is being rethought, with the mission and culture of the institutions changing due to globalization, resulting in new models of management and governance. The quality of Higher Education and its obligations to society are of current importance. The structural changes that the society has gone through requires a response in higher education that matches the changing needs of the society. Higher Education Institutions require new perspectives and a new strategic vision to cope with the uncertainty arising at a global scale, and this plays a role in their quality and whether they are leading institutions. Thus the following question arises: Which forms of management and governance contribute to the improvement of quality in higher education? The methodology for this study was designed with five stages: preparation of a plan of work within the thesis, the gradual progression to understanding the up-to-date understanding of Higher Education Research, generating research hypotheses and creating further understanding, writing the thesis with critical analysis and reflection. In addition to other relevant issues in higher education, different models were studied: Models of excellence, Models for implementation of Quality Management Systems, Environmental Management, Occupational Health and Safety Management, Risk Management, among others. Several indicators of Social Responsibility were created in this context and a pilot study was conducted in the area of Social Responsibility in Higher Education Institutions. Finally the conclusions resulting from the pilot study are presented and questions arising from the theoretical research are discussed. For example, the pilot study showed that there are indicators of a lack of understanding within the institutions to issues related to ethical and environmental education. Moreover, a large proportion of respondents said individuals have no opinion when confronted with questions on Responsible Social Involvement and Social Research and Social Management of Useful Knowledge. It is concluded that people have a vague awareness of these issues, so these concepts are new to them.

Planeamento de experiências : modelos e desafios dos planos em blocos incompletos

The main purpose of an Experimental Design resides mainly in the search for relationships between variables and in comparing levels of factors, using statistical treatment of collected data. The use of blocks in Experimental Design is essential because it allows reducing or eliminating the variability introduced by factors that can influence the experience but are not of main interest and/or were not explicitly included during experiments. In this work we present the results of the study and research of Balanced Incomplete Block Designs (BIBD), Balanced Incomplete Block Designs with repeated blocks (BIBDR) and the Incomplete Blocks Designs with blocks with different dimensions (VBBD). We explore some properties and construction methods of such designs and illustrate, when possible, with examples. Based on Block Designs, we present an application of BIBDR in Education, with the aim of comparing five domains of algebraic thinking in a sample of 1st year students of higher education in Cape Verde. For the analysis of sample data, the software R was used, version 2.12.1. We observed that significant differences exist between some of the domains of algebraic thinking, especially among the domains of Generalization of Arithmetic and Algebraic Technicality with the remaining areas. For a more representative sample, we recommend a bigger sample consisting of students from all higher institutions of Cape Verde.