Modelagem e simulação de sistema logístico de distribuição de carne de frango

O sistema logístico para distribuição de produtos acabados caracteriza-se pela integração dos serviços de comunicação, transporte e financeiros com a finalidade de atender às demandas do consumidor final. Estima-se que no estado do Espírito Santo, o consumo de carne de frango seja de 44,4 quilos per capita por ano. Para atender a esta demanda, o estado conta com matadouros-frigoríficos distribuídos pelo seu território, bem como, com a participação de outras empresas localizadas no país. Em sistemas de transportes, são característicos Problemas de Roteamento de Veículos (VRP), que precisam ser estudados, caracterizados e otimizados, normalmente, através de rotinas computacionais, que permitem avaliar maior quantidade de variáveis. O presente trabalho teve por objetivo caracterizar um VRP de um matadouro-frigorífico da região do Sul do Espírito Santo e desenvolver um aplicativo computacional que seja suporte para os gestores de logística, servindo para avaliar e propor rotas, e analisar parâmetros logísticos do processo de distribuição de produtos. No desenvolvimento do aplicativo computacional foi necessário caracterizar o sistema logístico da empresa, coletar e analisar os dados das operações logísticas, desenvolver as rotinas computacionais que representassem o sistema em estudo, verificar a confiabilidade dos resultados fornecidos pelo aplicativo, validá-lo e então, poder realizar as experimentações. O aplicativo desenvolvido permitiu reproduzir dados do sistema estudado e avaliar rotas segundo parâmetros logísticos. Pode-se concluir que o aplicativo computacional desenvolvido é útil aos gestores de logística, permitindo a avaliação das rotas praticadas e de novas configurações de rotas.

Reducing fuel consumption through modular vehicle architectures

By identifying energy waste streams in vehicles fuel consumption and introducing the concept of lean driving systems, a technological gap for reducing fuel consumption was identified. This paper proposes a solution to overcome this gap, through a modular vehicle architecture aligned with driving patterns. It does not address detailed technological solutions; instead it models the potential effects in fuel consumption through a modular concept of a vehicle and quantifies their dependence on vehicle design parameters (manifesting as the vehicle mass) and user behavior parameters (driving patterns manifesting as the use of a modular car in lighter and heavier mode, in urban and highway cycles). Modularity has been functionally applied in automotive industry as manufacture and assembly management strategies; here it is thought as a product development strategy for flexibility in use, driven by environmental concerns and enabled by social behaviors. The authors argue this concept is a step forward in combining technological solutions and social behavior, of which eco-driving is a vivid example, and potentially evolutionary to a lean, more sustainable, driving culture.

Knee muscle strength, balance and functional independence in persons with stroke

Purpose: to investigate the relationship between knee muscle strength, balance and functional independence within the first month after stroke. Relevance: cerebral vascular disease is one of the main causes of morbidity, disability and mortality in developed countries. Problems with movement control are frequent after stroke. Lower limb weakness and impaired balance are common problems that are related with the risk of falls and are likely to interfere with the ability to perform daily life activities. Physiotherapy intervention usually starts early after stroke and addresses impairments related to movement and posture in order to improve motor recovery and restore function.

Muscle strength, balance and functional independence in persons with stroke

Cerebral vascular disease is one of the main causes of morbidity, disability and mortality in developed countries. Problems with movement control are frequent after stroke. Lower limb weakness and impaired balance are common problems that are related with the risk of falls and are likely to interfere with the ability to perform daily life activities. Physiotherapy intervention usually starts early after stroke and addresses impairments related to movement and posture in order to improve motor recovery and restore function. Purpose: to investigate the relationship between knee muscle strength, balance and functional independence within the first month after stroke.

MASDSheGATS – Scheduling System for Dynamic Manufacturing Environments

This chapter addresses the resolution of scheduling in manufacturing systems subject to perturbations. The planning of Manufacturing Systems involves frequently the resolution of a huge amount and variety of combinatorial optimisation problems with an important impact on the performance of manufacturing organisations. Examples of those problems are the sequencing and scheduling problems in manufacturing management, routing and transportation, layout design and timetabling problems.

Energy efficient scheduling for cluster-tree wireless sensor networks with time-bounded data flows: application to IEEE 802.15.4/ZigBee

Cluster scheduling and collision avoidance are crucial issues in large-scale cluster-tree Wireless Sensor Networks (WSNs). The paper presents a methodology that provides a Time Division Cluster Scheduling (TDCS) mechanism based on the cyclic extension of RCPS/TC (Resource Constrained Project Scheduling with Temporal Constraints) problem for a cluster-tree WSN, assuming bounded communication errors. The objective is to meet all end-to-end deadlines of a predefined set of time-bounded data flows while minimizing the energy consumption of the nodes by setting the TDCS period as long as possible. Sinceeach cluster is active only once during the period, the end-to-end delay of a given flow may span over several periods when there are the flows with opposite direction. The scheduling tool enables system designers to efficiently configure all required parameters of the IEEE 802.15.4/ZigBee beaconenabled cluster-tree WSNs in the network design time. The performance evaluation of thescheduling tool shows that the problems with dozens of nodes can be solved while using optimal solvers.

Using remote labs to serve different teacher's needs a case study with VISIR and RemotElectLab

Remote Laboratories are an emergent technological and pedagogical tool at all education levels, and their widespread use is an important part of their own improvement and evolution. This paper describes several issues encountered on laboratorial classes, on higher education courses, when using remote laboratories based on PXI systems, either using the VISIR system or an alternate in-house solution. Three main issues are presented and explained, all reported by teachers that gave support to students use of remote laboratories. The first issue deals with the need to allow students to select the actual place where an ammeter is to be inserted on electric circuits, even incorrectly, therefore emulating real world difficulties. The second one deals with problems with timing when several measurements are required at short intervals, as in the discharge cycle of a capacitor. And the last issue deals with the use of a multimeter in DC mode when reading AC values, a use that collides with the lab settings. All scenarios are presented and discussed including the solution found for each case. The conclusion derived from the described work is that the remote laboratories area is an expanding field, where practical use leads to improvement and evolution of the available solutions, requiring a strict cooperation and information sharing between all actors, i.e. developers, teachers and students.

Integration of e-learning systems with repositories of learning objects

This paper describes a communication model to integrate repositories of programming problems with other e-Learning software components. The motivation for this work comes from the EduJudge project that aims to connect an existing repository of programming problems to learning management systems. When trying to use the existing repositories of learning objects we realized that they are mainly specialized search engines and lack features for integration with other e-Learning systems. With this model we intend to clarify the main features of a programming problem repository, in order to enable the design and development of software components that use it. The two main points of this model are the definition of programming problems as learning objects and the definition of the core functions exposed by the repository. In both cases, this model follows the existing specifications of the IMS standard and proposes extensions to deal with the special requirements of automatic evaluation and grading of programming exercises. In the definition of programming problems as learning objects we introduced a new schema for meta-data. This schema is used to represent meta-data related to automatic evaluation that cannot be conveniently represented using the standard: the type of automatic evaluation; the requirements of the evaluation engine; or the roles of different assets - tests cases, program solutions, etc. In the definition of the core functions we used two different web services flavours - SOAP and REST - and described each function as an operation for each type of interface. We describe also the data types of the arguments of each operation. These data types consist mainly on learning objects and their identifications, but include also usage reports and queries using XQuery.

"Gestão Oficinal no Setor Automóvel” - Caso de estudo na AMC, Lda.

A indústria automóvel no que respeita à gestão oficinal de qualidade é uma referência de dimensão e nível mundial. O constante avanço da indústria automóvel, o ciclo de vida dos produtos (automóveis) cada vez mais curtos e a competitividade entre empresas, requer uma procura constante de novas ferramentas de melhoria na gestão oficinal. Neste trabalho, centrado na gestão oficinal no setor automóvel, procuram-se introduzir novas abordagens que visem combater o decréscimo da rentabilidade neste setor. Como se depreende do exposto anteriormente, o objetivo principal desta dissertação é propor e avaliar (validar) propostas de melhoria que visem o aumento da rentabilidade financeira da empresa AMC – Auto Mecânica de Cambra, Lda. Com vista à prossecução deste objetivo foram definidos os seguintes objetivos intercalares na AMC: - Análise e levantamento dos problemas; - Identificação de potenciais causas; - Formulação de ações de propostas de melhoria na gestão da empresa; - Programação das ações e avaliação de resultados alcançados; A estrutura definida nesta dissertação após a sua introdução no capítulo 1 centra-se no capítulo 2 na apresentação da empresa AMC, com a descrição dos problemas levantados atendendo às vertentes mais críticas. Seguidamente, no capítulo 3, com ferramentas de análise de problemas, serão encontradas as causas raiz destes problemas. Posteriormente no capítulo seguinte serão criados planos de ações para a resolução das causas. No capítulo 4 as ações serão implementadas e avaliadas para garantir a sua eficácia e eficiência. Por fim, no capítulo 5 são descritas as conclusões e os desenvolvimentos futuros enquadráveis com a melhoria contínua da AMC. Como conclusão, este trabalho, mostra que várias propostas de melhoria implementadas trouxeram ganhos efetivos para a empresa e que futuras propostas são potencialmente válidas num futuro próximo. Esta dissertação com ligação direta à AMC tem igualmente dados que podem ser extrapolados e adaptados a outras empresas do mesmo setor. O objetivo principal deste estudo é a análise e o levantamento dos problemas com a utilização de ferramentas tais como: Benchmarking, Diagrama causa-efeito, ciclo PDCA, análise de SWOT e indicadores operativos da oficina.

Transporte internacional rodoviário de mercadorias: projecto de optimização operacional

No âmbito do estágio curricular realizado na DSV Transitários, surgiu a oportunidade de estar inserida em duas das áreas funcionais da empresa: durante o primeiro mês, no departamento comercial e nos restantes meses no departamento ROAD (rodoviário Internacional) no qual me foi proporcionado a oportunidade de desempenhar funções de Operacional de Tráfego Rodoviário Internacional. Desta forma, surge o desafio de integrar na equipa de operacionais ROAD da DSV, por forma a contribuir ativamente para a rotina da empresa e paralelamente analisar os processos operacionais do departamento, bem como, identificar todos os pontos que necessitem de melhoria. Após estar inserida neste sector, compreendi que a grupagem de mercadorias desempenha um papel fundamental neste departamento, na medida em que, quando desenvolvida de uma forma eficiente, pode traduzir-se numa atividade de extremo valor. A dinâmica diária desta atividade exige que os operadores de tráfego respondam de uma forma rápida e flexível aos problemas, apresentando soluções eficazes às solicitações do mercado. Para isso, é importante encontrar mecanismos capazes de os auxiliar na tomada decisões operacionais.

Sectors and routes in solid waste collection

Collecting and transporting solid waste is a constant problem for municipalities and populations in general. Waste management should take into account the preservation of the environment and the reduction of costs. The goal with this paper is to address a real-life solid waste problem. The case reveals some general and specific characteristics which are not rare, but are not widely addressed in the literature. Furthermore, new methods and models to deal with sectorization and routing are introduced, which can be extended to other applications. Sectorization and routing are tackled following a two-phase approach. In the first phase, a new method is described for sectorization based on electromagnetism and Coulomb’s Law. The second phase addresses the routing problems in each sector. The paper addresses not only territorial division, but also the frequency with which waste is collected, which is a critical issue in these types of applications. Special characteristics related to the number and type of deposition points were also a motivation for this work. A new model for a Mixed Capacitated Arc Routing Problem with Limited Multi-Landfills is proposed and tested in real instances. The computational results achieved confirm the effectiveness of the entire approach.

Electromagnetism based approach to Sector design in Waste Collection

For efficient planning of waste collection routing, large municipalities may be partitioned into convenient sectors. The real case under consideration is the municipality of Monção, in Portugal. Waste collection involves more than 1600 containers over an area of 220 km2 and a population of around 20,000 inhabitants. This is mostly a rural area where the population is distributed in small villages around the 33 boroughs centres (freguesia) that constitute the municipality. In most freguesias, waste collection is usually conducted 3 times a week. However, there are situations in which the same collection is done every day. The case reveals some general and specific characteristics which are not rare, but are not widely addressed in the literature. Furthermore, new methods and models to deal with sectorization and routing are introduced, which can be extended to other applications. Sectorization and routing are tackled following a three-phase approach. The first phase, which is the main concern of the presentation, introduces a new method for sectorization inspired by Electromagnetism and Coulomb’s Law. The matter is not only about territorial division, but also the frequency of waste collection, which is a critical issue in these types of applications. Special characteristics related to the number and type of deposition points were also a motivation for this work. The second phase addresses the routing problems in each sector: new Mixed Capacitated Arc Routing with Limited Multi-Landfills models will be presented. The last phase integrates Sectoring and Routing. Computational results confirm the effectiveness of the entire novel approach.

Implementation of an IoT-based Sensor Network Integrating IoT-based Sensor Networks with Large-Scale Message Distribution

As technology advances not only do new standards and programming styles appear but also some of the previously established ones gain relevance. In a new Internet paradigm where interconnection between small devices is key to the development of new businesses and scientific advancement there is the need to find simple solutions that anyone can implement in order to allow ideas to become more than that, ideas. Open-source software is still alive and well, especially in the area of the Internet of Things. This opens windows for many low capital entrepreneurs to experiment with their ideas and actually develop prototypes, which can help identify problems with a project or shine light on possible new features and interactions. As programming becomes more and more popular between people of fields not related to software there is the need for guidance in developing something other than basic algorithms, which is where this thesis comes in: A comprehensive document explaining the challenges and available choices of developing a sensor data and message delivery system, which scales well and implements the delivery of critical messages. Modularity and extensibility were also given much importance, making this an affordable tool for anyone that wants to build a sensor network of the kind.

A public transport bus assignment problem: parallel metaheuristics assessment

Combinatorial Optimization Problems occur in a wide variety of contexts and generally are NP-hard problems. At a corporate level solving this problems is of great importance since they contribute to the optimization of operational costs. In this thesis we propose to solve the Public Transport Bus Assignment problem considering an heterogeneous fleet and line exchanges, a variant of the Multi-Depot Vehicle Scheduling Problem in which additional constraints are enforced to model a real life scenario. The number of constraints involved and the large number of variables makes impracticable solving to optimality using complete search techniques. Therefore, we explore metaheuristics, that sacrifice optimality to produce solutions in feasible time. More concretely, we focus on the development of algorithms based on a sophisticated metaheuristic, Ant-Colony Optimization (ACO), which is based on a stochastic learning mechanism. For complex problems with a considerable number of constraints, sophisticated metaheuristics may fail to produce quality solutions in a reasonable amount of time. Thus, we developed parallel shared-memory (SM) synchronous ACO algorithms, however, synchronism originates the straggler problem. Therefore, we proposed three SM asynchronous algorithms that break the original algorithm semantics and differ on the degree of concurrency allowed while manipulating the learned information. Our results show that our sequential ACO algorithms produced better solutions than a Restarts metaheuristic, the ACO algorithms were able to learn and better solutions were achieved by increasing the amount of cooperation (number of search agents). Regarding parallel algorithms, our asynchronous ACO algorithms outperformed synchronous ones in terms of speedup and solution quality, achieving speedups of 17.6x. The cooperation scheme imposed by asynchronism also achieved a better learning rate than the original one.

A critical review of the possible benefits associated with homeopathic medicine

OBJECTIVE: To evaluate the recent scientific research progress on homeopathy. METHODOLOGY: Homeopathy was evaluated in terms of its clinical research; in vitro research, and physical foundations. The Medline database was the main reference source for the present research, concerning data of approximately the last 10 years. Secondary references (not available in this database) were obtained by means of direct requests to authors listed in the primary references. RESULTS: Clinical studies and in vitro research indicate the inefficacy of homeopathy. Some few studies with positive results are questionable because of problems with the quality and lack of appropriate experimental controls in these studies. The most recent meta-analyses on the topic yielded negative results. One of the few previous meta-analyses with positive results had serious publication bias problems, and its results were later substantially reconsidered by the main authors. The sparse in vitro homeopathic research with positive results has not been replicated by independent researchers, had serious methodological flaws, or when replicated, did not confirm the initial positive results. A plausible mechanism for homeopathic action is still nonexistent, and its formulation, by now, seems highly unlikely. CONCLUSIONS: As a result of the recent scientific research on homeopathy, it can be concluded that ample evidence exists to show that the homeopathic therapy is not scientifically justifiable.