A genetic algorithm for the job shop scheduling with a new local search using Monte Carlo method

This paper presents a methodology for applying scheduling algorithms using Monte Carlo simulation. The methodology is based on a decision support system (DSS). The proposed methodology combines a genetic algorithm with a new local search using Monte Carlo Method. The methodology is applied to the job shop scheduling problem (JSSP). The JSSP is a difficult problem in combinatorial optimization for which extensive investigation has been devoted to the development of efficient algorithms. The methodology is tested on a set of standard instances taken from the literature and compared with others. The computation results validate the effectiveness of the proposed methodology. The DSS developed can be utilized in a common industrial or construction environment.

Design optimization of cruciform specimens for biaxial fatigue loading

In order to correctly assess the biaxial fatigue material properties one must experimentally test different load conditions and stress levels. With the rise of new in-plane biaxial fatigue testing machines, using smaller and more efficient electrical motors, instead of the conventional hydraulic machines, it is necessary to reduce the specimen size and to ensure that the specimen geometry is appropriated for the load capacity installed. At the present time there are no standard specimen’s geometries and the indications on literature how to design an efficient test specimen are insufficient. The main goal of this paper is to present the methodology on how to obtain an optimal cruciform specimen geometry, with thickness reduction in the gauge area, appropriated for fatigue crack initiation, as a function of the base material sheet thickness used to build the specimen. The geometry is optimized for maximum stress using several parameters, ensuring that in the gauge area the stress is uniform and maximum with two limit phase shift loading conditions. Therefore the fatigue damage will always initiate on the center of the specimen, avoiding failure outside this region. Using the Renard Series of preferred numbers for the base material sheet thickness as a reference, the reaming geometry parameters are optimized using a derivative-free methodology, called direct multi search (DMS) method. The final optimal geometry as a function of the base material sheet thickness is proposed, as a guide line for cruciform specimens design, and as a possible contribution for a future standard on in-plane biaxial fatigue tests. © 2014, Gruppo Italiano Frattura. All rights reserved.

A Web-Based geographical information system prototype on Portuguese traditional food products

Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial Technologies

Invariant integrals applied to nematic liquid crystals with small Ericksen number and topological defects

Invariant integrals are derived for nematic liquid crystals and applied to materials with small Ericksen number and topological defects. The nematic material is confined between two infinite plates located at y = -h and y = h (h is an element of R+) with a semi-infinite plate at y = 0 and x < 0. Planar and homeotropic strong anchoring boundary conditions to the director field are assumed at these two infinite and semi-infinite plates, respectively. Thus, a line disclination appears in the system which coincides with the z-axis. Analytical solutions to the director field in the neighbourhood of the singularity are obtained. However, these solutions depend on an arbitrary parameter. The nematic elastic force is thus evaluated from an invariant integral of the energy-momentum tensor around a closed surface which does not contain the singularity. This allows one to determine this parameter which is a function of the nematic cell thickness and the strength of the disclination. Analytical solutions are also deduced for the director field in the whole region using the conformal mapping method. (C) 2013 Elsevier Ltd. All rights reserved.

X Radiation dose implications in screening patients with ferromagnetic IOFBs prior to MRI: a literary review

Patients scheduled for a magnetic resonance imaging (MRI) scan sometimes require screening for ferromagnetic Intra Orbital Foreign Bodies (IOFBs). To assess this, they are required to fill out a screening protocol questionnaire before their scan. If it is established that a patient is at high risk, radiographic imaging is necessary. This review examines literature to evaluate which imaging modality should be used to screen for IOFBs, considering that the eye is highly sensitive to ionising radiation and any dose should be minimised. Method: Several websites and books were searched for information, these were as follows: PubMed, Science Direct, Web of Knowledge and Google Scholar. The terms searched related to IOFB, Ionising radiation, Magnetic Resonance Imaging Safety, Image Quality, Effective Dose, Orbits and X-ray. Thirty five articles were found, several were rejected due to age or irrelevance; twenty eight were eventually accepted. Results: There are several imaging techniques that can be used. Some articles investigated the use of ultrasound for investigation of ferromagnetic IOFBs of the eye and others discussed using Computed Tomography (CT) and X-ray. Some gaps in the literature were identified, mainly that there are no articles which discuss the lowest effective dose while having adequate image quality for orbital imaging. Conclusion: X-ray is the best method to identify IOFBs. The only problem is that there is no research which highlights exposure factors that maintain sufficient image quality for viewing IOFBs and keep the effective dose to the eye As Low As Reasonably Achievable (ALARA).

Serviço de visualização de informação geográfica na WEB - A publicação do atlas de Portugal utilizando a especificação WEB MAP SERVICE

Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Ciência e Sistemas de Informação Geográfica

Modelização de equivalente eléctrico para rede de nervuras de folhas vegetais

A tese tem como objectivo principal a criação de um modelo equivalente eléctrico da rede de nervuras de algumas folhas vegetais e analisar o seu comportamento a estímulos eléctricos, analisando-se também a respectiva resposta em frequência. A motivação desta tese passa pela observação dos sistemas existentes na natureza. Neste caso, as folhas vegetais e analisar se são sistemas de ordem fraccionária ou não. Para a sua elaboração, fez-se uma breve abordagem à estrutura das plantas, sob o ponto de vista da botânica e elaborou-se um método de fotografia das amostras, mapeamento da rede de nervuras e medição dos segmentos que compõem essa mesma rede. A tese termina com um capítulo de resultados experimentais.

Optimal design for active damping in sandwich structures using the Direct MultiSearch method

This paper addresses the problem of optimal positioning of surface bonded piezoelectric patches in sandwich plates with viscoelastic core and laminated face layers. The objective is to maximize a set of modal loss factors for a given frequency range using multiobjective topology optimization. Active damping is introduced through co-located negative velocity feedback control. The multiobjective topology optimization problem is solved using the Direct MultiSearch Method. An application to a simply supported sandwich plate is presented with results for the maximization of the first six modal loss factors. The influence of the finite element mesh is analyzed and the results are, to some extent, compared with those obtained using alternative single objective optimization.

Web GIS to support irrigation management: a prototype for SAGRA network, Alentejo Portugal

Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial Technologies

Novos processos e produtos para o couro de base vegetal

Mestrado em Engenharia Química - Ramo Optimização Energética na Indústria Química

O futuro da web semântica e sua importância nas organizações

Trabalho realizado sob orientação do Prof. António Brandão Moniz para a disciplina “Factores Sociais da Inovação” do Mestrado Engenharia Informática realizado na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa (Portugal)

Filtering method in backlash phenomena analysis

The behavior of robotic manipulators with backlash is analyzed. Based on the pseudo-phase plane two indices are proposed to evaluate the backlash effect upon the robotic system: the root mean square error and the fractal dimension. For the dynamical analysis the noisy signals captured from the system are filtered through wavelets. Several tests are developed that demonstrate the coherence of the results.

Schem@Doc: a web-based XML schema visualizer

XML Schema is one of the most used specifications for defining types of XML documents. It provides an extensive set of primitive data types, ways to extend and reuse definitions and an XML syntax that simplifies automatic manipulation. However, many features that make XML Schema Definitions (XSD) so interesting also make them rather cumbersome to read. Several tools to visualize and browse schema definitions have been proposed to cope with this issue. The novel approach proposed in this paper is to base XSD visualization and navigation on the XML document itself, using solely the web browser, without requiring a pre-processing step or an intermediate representation. We present the design and implementation of a web-based XML Schema browser called schem@Doc that operates over the XSD file itself. With this approach, XSD visualization is synchronized with the source file and always reflects its current state. This tool fits well in the schema development process and is easy to integrate in web repositories containing large numbers of XSD files.

Plataforma web de informação automobilística

Esta dissertação enquadra-se no âmbito dos Sistemas de Informação, em concreto, no desenvolvimento de aplicações Web, como é o caso de um website. Com a utilização em larga escala dos meios tecnológicos tem-se verificado um crescimento exponencial dos mesmos, o que se traduz na facilidade com que podem ser encontradas na Internet diversos tipos de plataformas informáticas. Além disso, hoje em dia, uma grande parte das organizações possui o seu próprio sítio na Internet, onde procede à divulgação dos seus serviços e/ou produtos. Pretende-se com esta dissertação explorar estas novas tecnologias, nomeadamente, os diagramas UML - Unified Modeling Language e a concepção de bases de dados, e posteriormente desenvolver um website. Com o desenvolvimento deste website não se propõe a criação de uma nova tecnologia, mas o uso de diversas tecnologias em conjunto com recurso às ferramentas UML. Este encontra-se organizado em três fases principais: análise de requisitos, implementação e desenho das interfaces. Na análise de requisitos efectuou-se o levantamento dos objectivos propostos para o sistema e das necessidades/requisitos necessários à sua implementação, auxiliado essencialmente pelo Diagrama de Use Cases do sistema. Na fase de implementação foram elaborados os arquivos e directórios que formam a arquitectura lógica de acordo com os modelos descritos no Diagrama de Classes e no Diagrama de Entidade-Relação. Os requisitos identificados foram analisados e usados na composição das interfaces e sistema de navegação. Por fim, na fase de desenho das interfaces foram aperfeiçoadas as interfaces desenvolvidas, com base no conceito artístico e criativo do autor. Este aperfeiçoamento vai de encontro ao gosto pessoal e tem como objectivo elaborar uma interface que possa também agradar ao maior número possível de utilizadores. Este pode ser observado na maneira como se encontram distribuídas as ligações (links) entre páginas, nos títulos, nos cabeçalhos, nas cores e animações e no seu design em geral. Para o desenvolvimento do website foram utilizadas diferentes linguagens de programação, nomeadamente a HyperText Markup Language (HTML), a Page Hypertext Preprocessor (PHP) e Javascript. A HTML foi utilizada para a disposição de todo o conteúdo visível das páginas e para definição do layout das mesmas e a PHP para executar pequenos scripts que permitem interagir com as diferentes funcionalidades do site. A linguagem Javascript foi usada para definir o design das páginas e incluir alguns efeitos visuais nas mesmas. Para a construção das páginas que compõem o website foi utilizado o software Macromedia Dreamweaver, o que simplificou a sua implementação pela facilidade com que estas podem ser construídas. Para interacção com o sistema de gestão da base de dados, o MySQL, foi utilizada a aplicação phpMyAdmin, que simplifica o acesso à base de dados, permitindo definir, manipular e consultar os seus dados.

MediaAccess - componentes para acesso a informação multimédia na web

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Engenharia Informática