70 research outputs found

    Selecting a Flexible Manufacturing System Using Multiple Criteria Analysis

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    This paper describes a visually interactive decision support framework designed to aid the decision maker, typically top management, in selecting the most appropriate technology and design, when planning a flexible manufacturing system (FMS). The framework can be used in the pre-investment stage of the planning process, after the decision in principle has been made to build an FMS. First, both qualitative and quantitative criteria are used to narrow the set of alternative system configurations under consideration down to a small number of most attractive candidates. After this pre-screening phase, a multiobjective programming model is formulated for each remaining configuration, allowing the manager to explore and evaluate the costs and benefits of various different scenarios for each configuration separately by experimenting with different levels of batch sizes and production volumes. The system uses visual interaction with the decision maker, graphically displaying the relevant tradeoffs between such relevant performance criteria as investment and production costs, manufacturing flexibility, production volume and investment risk, for each scenario. Additional criteria, when relevant, can be included as well. The ease of use and interpretation and the flexibility make the proposed system a powerful analytical tool in the initial FMS design process. The insights gained from experimenting with the different scenarios form the basis of understanding the anticipated impact of techno-economic factors on the performance of the FMS configuration, and provide valuable information for the implementation stage of building the FMS. An example using real data from a case study in the Finnish metal product industry is provided to illustrate the methodology

    A Nonlinear Multicriteria Model for Strategic FMS Selection Decisions

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    The strategic decision of selecting an optimal flexible manufacturing system (FMS) configuration is a complicated question which involves evaluating tradeoffs between a number of different, potentially conflicting criteria such as annual production volume, flexibility, production and investment costs, and average throughput of the system. Recently, several structured approaches have been proposed to aid management in the FMS selection process. While acknowledging the nonlinear nature of a number of the relationships in the model, notably between batch size and the number of batches produced of each part, these studies used linear simplifications to illustrate the decision dynamics of the problem. These linear models were shown to offer useful analytical tools in the FMS pre-design process. Due to the nonlinearities of the true relationships, however, the tradeoffs between the criteria could not fully be explored within the linear framework. This paper builds on the two-phase decision support framework proposed by Stam and Kuula (1989), and uses a modified nonlinear multicriteria formulation to solve the problem. The software used in the illustration can easily be implemented, is user-interactive and menu-driven. The methodology is applied to real data from a Finnish metal product company, and the results are compared with those obtained in previous studies

    Transboundary Air Pollution in Europe: An Interactive Multicriteria Tradeoff Analysis

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    In this paper. the acid rain problem in Europe is discussed, stressing the transboundary tradeoffs between abatement costs of sulphur emission reduction and corresponding deposition levels in the different countries. An interactive decision support methodology is proposed which utilizes a powerful nonlinear multicriteria software package to evaluate various scenarios and tradeoffs. The concepts are illustrated using previously published data. The results from the tradeoff analysis show that reasonable deposition levels can be reached with limited transfers of funds between countries. The extent of these transfers can be controlled by selecting appropriate target levels for the criteria across countries

    Health service use and costs associated with fluoroquinolone-related tendon injuries

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    Y The aim of this study was to assess costs and health service use associated with tendon injuries after the use of fluoroquinolone antimicrobialsin Finland during 2002-2012. This retrospective observational study included data from the Finnish Pharmaceutical Insurance Pool's pharmaceutical injury claims. In total, 145 compensated claimants aged >= 18 years presenting tendon injuries after the use of fluoroquinolones (FQs) were included in the study. Outcomes of interest were the number of outpatient visits to primary, secondary, tertiary, and private healthcare services, hospital days, rehabilitation and their costs. Regression models were used to analyze the impact of patient characteristics on hospital days, as well as the relationship between patient characteristics and tendon ruptures. Direct costs of a tendon injury averaged 14,800euro and indirect costs were estimated to be 9,077euro for employed claimants. Fifty-one percent of the claimants were hospitalized, with an average duration of 21 days. Hospitalization was the costliest form of health service use with an average of 9,915euro per hospital episode. Hospital days and direct costs increased with the severity of the injury. Tendon ruptures, in particular bilateral ruptures, required substantially more hospital days and their direct costs were significantly higher than those of uncomplicated tendinitis. Concurrent use of oral corticosteroids and increasing age were associated with a higher likelihood of tendon ruptures. Although rare, FQ-related tendon injuries can result in considerable costs and health service use. Medical staff should remain vigilant when prescribing FQs, especially in groups at increased risk for tendon injuries.Peer reviewe

    Fluoroquinolone-related adverse events resulting in health service use and costs : A systematic review

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    Background and objectives Adverse events (AEs) associated with the use of fluoroquinolone antimicrobials include Clostridium difficile associated diarrhea (CDAD), liver injury and seizures. Yet, the economic impact of these AEs is seldom acknowledged. The aim of this review was to identify health service use and subsequent costs associated with ciprofloxacin, levofloxacin, moxifloxacin, norfloxacin and ofloxacin -related AEs. Methods A literature search covering Medline, SCOPUS, Cinahl, Web of Science and Cochrane Library was performed in April 2017. Two independent reviewers systematically extracted the data and assessed the quality of the included studies. All costs were converted to 2016 euro in order to improve comparability. Results Of the 5,687 references found in the literature search, 19 observational studies, of which five were case-controlled, fulfilled the inclusion criteria. Hospitalization was an AE-related health service use outcome in 17 studies. Length of hospital stay associated with AEs varied between <5 and 45 days. The estimated cost of an AE episode ranged between 140 and 18,252 (sic). CDAD was associated with the longest stays in hospital. Ten studies reported AE-related length of stays and five evaluated costs associated with AEs. Due to the lack of published literature, health service use and costs associated with many high-risk FQ-related AEs could not be evaluated. Conclusions Because of the wide clinical use of fluoroquinolones, in particular serious fluoroquinolone-related AEs can have substantial economic implications, in addition to imposing potentially devastating health complications for patients. Further measures are required to prevent and reduce health service use and costs associated with fluoroquinolone-related AEs. Equally, better-quality reporting and additional published data on health service use and costs associated with AEs are needed.Peer reviewe

    Selecting a Flexible Manufacturing System using Multiple Criteria Analysis

    Get PDF
    A visual interactive decision support framework designed to aid the decision-maker, typically top management, in selecting the most appropriate technology and design when planning a flexible manufacturing system (FMS) is described. The framework can be used in the preinvestment stage of the planning process, after the decision in principle has been made to build an FMS. First, both qualitative and quantitative criteria are used to narrow the set of alternative system configurations under consideration down to a small number of most attractive candidates. After this prescreening phase, a multiobjective programming model is formulated for each remaining configuration, allowing the manager to explore and evaluate the costs and benefits of various different scenarios for each configuration separately by experimenting with different levels of batch sizes and production volumes. The system uses visual interaction with the decision-maker, graphically displaying the relevant trade-offs between such relevant performance criteria as investment and production costs, manufacturing flexibility, production volume and investment risk, for each scenario. Additional criteria, when relevant, can also be included. The ease of use and interpretation and the flexibility make the proposed system a powerful analytical tool in the initial FMS design process. The insights gained from experimenting with the different scenarios form the basis of understanding the anticipated impact of techno-economic factors on the performance of the FMS configuration, and provide valuable information for the implementation stage of building the FMS. An example using real data from a case study in the Finnish metal product industry is provided to illustrate the methodology

    Social relationships, child poverty, and children's life satisfaction

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    Child subjective well-being is determined by various personal, social, and contextual factors. Few studies have found reliable differences in the prediction power of these factors; however, the results vary especially when it comes to sociodemographic factors, such as the effect of child’s socioeconomic background on life satisfaction. This paper examines how poverty and social relationships affect the perceived life satisfaction of Finnish schoolchildren. Drawing on survey data of Finnish schoolchildren, from grades 5, 7, and 9 (n = 1793), linear regression was used to test how life satisfaction would be associated with socio-demographic variables, poverty, and child–parent and peer relationships. The results emphasize the complex nature of the determinants of children’s life satisfaction. The greatest unique contribution for change of life satisfaction was made by the time spent with mother (β(p) = 0.189). Overall, the model showed a good fit (R2 19.9). These findings have important implications for family policies and services that promote good parenting and positive parent–child relationships. Furthermore, this study highlights relational well-being as a key determinant of children’s life satisfaction.</p

    Transboundary Air Pollution in Europe: An Interactive Multicriteria Tradeoff Analysis

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    In this report, the acid rain problem in Europe is discussed, stressing the transboundary tradeoffs between abatement costs of sulphur emission reduction and corresponding deposition levels in the different countries. An interactive decision support methodology is proposed which utilizes a powerful nonlinear multicriteria software package to evaluate various scenarios and tradeoffs. This methodology provides a more appropriate tool for policy making than single-objective minimization of costs with given target deposition levels, because in the latter the tradeoffs cannot be analyzed directly. The results from a tradeoff analysis using previously published data suggest that reasonable deposition levels can be reached with limited transfers of funds between countries. The extent of these transfers can be controlled by selecting appropriate target levels for the criteria across countries

    Business students' value priorities and attitudes towards sustainable development

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    Business students of today are future executives in companies and governments. Therefore, their education for sustainability needs to be carefully considered. However, very little is known about business students in terms of their value priorities and attitudes towards sustainable development. Value priorities guide attitudes, but they are more abstract and long-lasting. Teachers who understand their students' value priorities and attitudes could develop and customize their teaching accordingly. Our goal in this study is to measure business students' value priorities and their attitudes towards sustainability. We compare the results obtained from students in a university business school with a comparable nationwide sample. Our results show that there are differences in almost all values among business students and the comparable sample, in particular in universalism and power. Interestingly, attitudes to sustainable development are equally or even more favorable among business students. As a theoretical contribution in the field of education for sustainability we combined Sterling's three levels of sustainability education into our considerations and suggest that the evolvement of students' values and sustainability attitudes measured regularly should be reflected against them or a corresponding categorization. (C) 2020 The Authors. Published by Elsevier Ltd

    Using big data to explore worldwide trends in objective sleep in the transition to adulthood

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    Background: Development induces changes in sleep, and its duration has been reported to change as a function of aging. Additionally, sleep timing is a marker of pubertal maturation, where during adolescence, the circadian rhythm shifts later. Typically, this is manifested in a later sleep onset in the evening and later awakening in the morning. These changes across development seem to be universal around the world but are unlikely to persist into adulthood. Methods: This study utilized accelerometer data from 17,355 participants aged 16-30 years (56% female) measured by validated Polar wearables over a 14-day period. We compared sleep duration, chronotype (sleep midpoint) and weekend catch-up (ie, social jetlag) sleep across ages and regions over 242,948 nights. Results: The data indicate a decline in sleep duration as well as a dramatic shift in sleep onset times throughout adolescence. This continues well into early adulthood and stabilizes nearer age 30. Differences in sleep duration across ages were significant, and ranged from 7:53 h at age 16 to 7:29 h at age 30 in the sample. Additionally, there was a clear difference between females and males throughout adolescence and young adulthood: girls had longer sleep duration and earlier timed sleep in the current study. Differences in sleep were found between regions across the world, and across European areas. Conclusions: Both sleep duration and sleep timing go through a clear developmental pattern, particularly in early adulthood. Females had an earlier sleep midpoint and obtained more sleep. Regional differences in sleep occurred across the world. Crown Copyright (C) 2019 Published by Elsevier B.V. All rights reserved.Peer reviewe
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