105 research outputs found

    Modified Fuzzy FMEA Application in the Reduction of Defective Poultry Products

    Get PDF
    Failure mode and effects analysis (FMEA) consists of the famous qualitative management methods used for improvements in management processes. This paper aims to determine the factors of defective products in the processing of poultry products in the industry. The causes of problems have been analyzed by systematic brainstorming of specialist consensus in the evaluation of problems to achieve unanimity on the violence level. The FMEA method uses the risk priority number (RPN), which indicates the priorities of risk problems and can evaluate three components: severity, occurrence and detection. Sometimes, this risk assessment leads to the wrong priorities. Therefore, we propose fuzzy FMEA methods for priority ranking of RPN and efficiently reducing poultry product defects, which are established based on fuzzy systems followed by comparison with conventional FMEA. The results indicate that the fuzzy FMEA method can efficiently and feasibly reduce poultry product defects

    A new risk prioritization model for reliability assessment in design phase of new products 

    Get PDF
    Trabalho final de mestrado para obtenção do grau de mestre em Engenharia MecânicaNowadays, companies take very seriously the subject of product quality, and make great efforts to guarantee that a reliable product is deployed into the market. Early detection of product faults is less costly and easier to correct. Therefore, companies tend to proceed with reliability tasks along all product development stages, such as Failure Modes and Effects Analysis (FMEA) which is a well-known tool used to identify failure modes and thus enhance system reliability through the development of suitable correction actions. Few companies have the resources to tackle all failure modes so they resort to prioritization methodologies in order to focus on the most critical ones. The most commonly prioritization methodology used worldwide is the Risk Priority Number (RPN). However, it has been raised by scientific community awareness towards RPN shortcomings that may result in misleading prioritization outcomes. Despite all the critics, conventional RPN is still utilized worldwide for prioritization of failure modes, probably due to its simplicity. In this study, it is proposed an alternative computation model (RPN beta - RPNb) for risk prioritization, which attempts to maintain application simplicity while eliminating some of conventional RPN shortcomings – 1) No consideration of risk drivers’ relative importance, 2) repetition of RPN values through different risk drivers’ combinations, 3) non-continuity of RPN values scale, and 4) high sensitiveness to variations in risk drivers scoring. Companies cannot rely on ineffective methodologies to support the decision-making, and implementation of corrective action for reliability improvement is not an exception. It is of utmost importance to replace the utilization of conventional RPN for failure modes prioritization. Based on a comparative analysis of a case study, RPNb presents itself as an apparently robust alternative, capable of delivering sustained results, adjustable to industry/area specific characteristics, through a straightforward computation mode.Atualmente, as empresas tratam a questão da qualidade de produtos com seriedade, e procedem a grandes esforços para colocar no mercado produtos fiáveis. Neste sentido, as empresas promovem tarefas com vista o aumento da fiabilidade durante todo o ciclo de vida do produto. A Análise de Modos de Falha e Efeitos (FMEA) é uma ferramenta usada a nível mundial na identificação de modos de falha e assim promover o aumento da fiabilidade através da implementação de ações corretivas. São poucas as empresas que possuem os recursos necessários para retificar todos os modos de falha identificados, e como tal recorrem a metodologias de priorização de modo a orientar esforços nos mais críticos. A metodologia de priorização mais comum é o Número Prioritário de Risco (RPN). No entanto, este tem sido alvo de críticas por parte da comunidade científica devido à existência de lacunas que podem levar a resultados enganadores. Apesar das críticas, o RPN convencional é ainda utilizado mundialmente na priorização de modos de falha, provavelmente devido à sua simplicidade. Neste estudo, é proposto um modelo de computação alternativo (RPNb) para priorização de risco com vista a eliminação de algumas lacunas do RPN convencional – Não consideração da importância relativa dos parâmetros de risco; Repetição dos valores de RPN através de diferentes combinações dos parâmetros de risco; Nãocontinuidade da escala RPN; Elevada sensibilidade a variações na pontuação dos parâmetros de risco – e a manutenção da simplicidade de aplicação. Na procura pela melhoria da fiabilidade, as empresas não devem suportar a tomada de decisão em metodologias pouco eficazes. Assim, é importante promover a substituição do RPN convencional na priorização de modos de falha. Neste sentido, e com base no caso de estudo, o RPNb é uma alternativa aparentemente robusta, capaz de fornecer resultados coerentes, ajustadável às características da indústria/área, através de um modelo simples.N/

    Considering stakeholders’ preferences for scheduling slots in capacity constrained airports

    Get PDF
    Airport slot scheduling has attracted the attention of researchers as a capacity management tool at congested airports. Recent research work has employed multi-objective approaches for scheduling slots at coordinated airports. However, the central question on how to select a commonly accepted airport schedule remains. The various participating stakeholders may have multiple and sometimes conflicting objectives stemming from their decision-making needs. This complex decision environment renders the identification of a commonly accepted solution rather difficult. In this presentation, we propose a multi-criteria decision-making technique that incorporates the priorities and preferences of the stakeholders in order to determine the best compromise solution

    Fuelling the zero-emissions road freight of the future: routing of mobile fuellers

    Get PDF
    The future of zero-emissions road freight is closely tied to the sufficient availability of new and clean fuel options such as electricity and Hydrogen. In goods distribution using Electric Commercial Vehicles (ECVs) and Hydrogen Fuel Cell Vehicles (HFCVs) a major challenge in the transition period would pertain to their limited autonomy and scarce and unevenly distributed refuelling stations. One viable solution to facilitate and speed up the adoption of ECVs/HFCVs by logistics, however, is to get the fuel to the point where it is needed (instead of diverting the route of delivery vehicles to refuelling stations) using "Mobile Fuellers (MFs)". These are mobile battery swapping/recharging vans or mobile Hydrogen fuellers that can travel to a running ECV/HFCV to provide the fuel they require to complete their delivery routes at a rendezvous time and space. In this presentation, new vehicle routing models will be presented for a third party company that provides MF services. In the proposed problem variant, the MF provider company receives routing plans of multiple customer companies and has to design routes for a fleet of capacitated MFs that have to synchronise their routes with the running vehicles to deliver the required amount of fuel on-the-fly. This presentation will discuss and compare several mathematical models based on different business models and collaborative logistics scenarios

    Management: A continuing literature survey with indexes

    Get PDF
    This bibliography lists 782 reports, articles, and other documents introduced into the NASA scientific and technical information system in 1977. The citations, and abstracts when available, are reproduced exactly as they appeared originally in IAA and STAR, including the original accession numbers from the respective announcement journals. Topics cover the management of research and development contracts, production, logistics, personnel, safety, reliability and quality control citations. Includes references on: program, project and systems management; management policy, philosophy, tools, and techniques; decisionmaking processes for managers; technology assessment; management of urban problems; and information for managers on Federal resources, expenditures, financing, and budgeting

    Sustainable Smart Cities and Smart Villages Research

    Get PDF
    ca. 200 words; this text will present the book in all promotional forms (e.g. flyers). Please describe the book in straightforward and consumer-friendly terms. [There is ever more research on smart cities and new interdisciplinary approaches proposed on the study of smart cities. At the same time, problems pertinent to communities inhabiting rural areas are being addressed, as part of discussions in contigious fields of research, be it environmental studies, sociology, or agriculture. Even if rural areas and countryside communities have previously been a subject of concern for robust policy frameworks, such as the European Union’s Cohesion Policy and Common Agricultural Policy Arguably, the concept of ‘the village’ has been largely absent in the debate. As a result, when advances in sophisticated information and communication technology (ICT) led to the emergence of a rich body of research on smart cities, the application and usability of ICT in the context of a village has remained underdiscussed in the literature. Against this backdrop, this volume delivers on four objectives. It delineates the conceptual boundaries of the concept of ‘smart village’. It highlights in which ways ‘smart village’ is distinct from ‘smart city’. It examines in which ways smart cities research can enrich smart villages research. It sheds light on the smart village research agenda as it unfolds in European and global contexts.

    A Statistical Approach to the Alignment of fMRI Data

    Get PDF
    Multi-subject functional Magnetic Resonance Image studies are critical. The anatomical and functional structure varies across subjects, so the image alignment is necessary. We define a probabilistic model to describe functional alignment. Imposing a prior distribution, as the matrix Fisher Von Mises distribution, of the orthogonal transformation parameter, the anatomical information is embedded in the estimation of the parameters, i.e., penalizing the combination of spatially distant voxels. Real applications show an improvement in the classification and interpretability of the results compared to various functional alignment methods
    • …
    corecore