CIEG - Artigos de Revistas Internacionais com Arbitragem Científica

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http://hdl.handle.net/10437/11092

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    The East Atlantic Bluefin Tuna Fisheries: Stock Collapse or Recovery?
    (The University of Chicago Press, 2006) Brasão, Ana; Bjorndal, Trond; Escola de Ciências Económicas e das Organizações
    A discrete time, multi-gear, and age structured bio-economic model is developed for the East Atlantic bluefin tuna fisheries, a paradigmatic example of the difficulties faced in managing highly migratory fish stocks. The model is used to analyse alternative management strategies for the Regional Fisheries Management Organisation (RFMO) managing this fishery, and to investigate some of the policy implications. For the various scenarios, the optimal stock level varies between 500–800,000 tonnes, which compares with a stock level of 150,000 tonnes in 1995. In other words, there is a very strong case for rebuilding the stock. Moreover, the sustainability of the stock is threatened unless a recovery programme is implemented; indeed, the alternative may be stock collapse. Second, to rebuild the stock, Draconian measures are called for: either outright moratoria over fairly lengthy periods, or possibly a more gradual approach to steady state given by a Total Allowable Catch (TAC) at a low level for an extended period of time. Third, the cost of inefficient gear structure is very high indeed.
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    The challenges of the IS/IT projects in the healthcare sector
    (IGI Global, 2019) Gomes, Jorge; Romão, Mário; Escola de Ciências Económicas e das Organizações
    Essentially, the purpose of investment in information systems and information technology (IS/IT) is to improve the operational efficiency of the organizations, reducing costs and improving levels of quality. Thus, many traditional appraisal techniques are used to evaluate tangible benefits, which are based on direct project costs. Since the 1980s, IS/IT has positioned itself as a strategic tool that through flexibility and innovative ways can produce superior performance. The health sector has sought to improve its effectiveness and efficiency by adopting IS/IT solutions to increase the quality of services, namely patient safety, organizational efficiency, and end-user satisfaction. Hospitals are complex organizations, and this complexity magnifies the opportunity for inevitable human errors. A poorly integrated system can decrease operational efficiency and reduce the quality of healthcare services. The issue remains controversial, as evidenced by several articles. The authors noticed that emergent technologies may offer opportunities to those who can exploit them effectively.
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    A system dynamics-based simulation experiment for testing mental model and performance effects of using the balanced scorecard
    (John Wiley & Sons, 2009-01) Capelo, Carlos; Dias, João Ferreira; Escola de Ciências Económicas e das Organizações
    This study develops a theoretical model that explains the effectiveness of the balanced scorecard approach by means of a system dynamics and feedback learning perspective. Presumably, the balanced scorecard leads to a better understanding of context, allowing managers to externalize and improve their mental models. We present a set of hypotheses about the influence of the balanced scorecard approach on mental models and performance. A test based on a simulation experiment that uses a system dynamics model is performed. The experiment included three types of parameters: financial indicators; balanced scorecard indicators; and balanced scorecard indicators with the aid of a strategy map review. Two out of the three hypotheses were confirmed. It was concluded that a strategy map review positively influences mental model similarity, and mental model similarity positively influences performance.
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    A Feedback Learning and Mental Models Perspective on Strategic Decision Making
    (Springer, 2009-04) Capelo, Carlos; Dias, João Ferreira; Escola de Ciências Económicas e das Organizações
    This study aims to be a contribution to a theoretical model that explains the effectiveness of the learning and decision-making processes by means of a feedback and mental models perspective. With appropriate mental models, managers should be able to improve their capacity to deal with dynamically complex contexts, in order to achieve long-term success. We present a set of hypotheses about the influence of feedback information and systems thinking facilitation on mental models and management performance. We explore, under controlled conditions, the role of mental models in terms of structure and behaviour. A test based on a simulation experiment with a system dynamics model was performed. Three out of the four hypotheses were confirmed. Causal diagramming positively influences mental model structure similarity, mental model structure similarity positively influences mental model behaviour similarity, and mental model behaviour similarity positively influences the quality of the decision
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    Systems thinking: learning or driving?
    (ISTCE Business School, 2007-04) Capelo, Carlos; Dias, João Ferreira; Escola de Ciências Económicas e das Organizações
    The ability to foresee how behaviour of a system arises from the interaction of its components over time - i.e. its dynamic complexity – is seen an important ability to take effective decisions in our turbulent world. Dynamic complexity emerges frequently from interrelated simple structures, such as stocks and flows, feedbacks and delays (Forrester, 1961). Common sense assumes an intuitive understanding of their dynamic behaviour. However, recent researches have pointed to a persistent and systematic error in people understanding of those building blocks of complex systems. This paper describes an empirical study concerning the native ability to understand systems thinking concepts. Two different groups - one, academic, the other, professional – submitted to four tasks, proposed by Sweeney and Sterman (2000) and Sterman (2002). The results confirm a poor intuitive understanding of the basic systems concepts, even when subjects have background in mathematics and sciences.
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    Public sector shared services and the lean methodology : implications on military organizations
    (Edições Universitárias Lusófonas, 2020) Costa, Renato Lopes da; Resende, Tiago; Dias, Álvaro Lopes; Pereira, Leandro; António, Nelson Santos; Escola de Ciências Económicas e das Organizações
    During the economic and financial crisis, private and public organizations were subject to a constant reduction in costs and resources. Public shared service models felt compelled to adopt the Lean methodology with the aim of reducing costs, reducing waste and increasing employee satisfaction with the provision of quality services. Against this background, this article aims to evaluate the impact of the implementation of Shared Services and the inherent benefits of lean management in the Military Store, Contact Center, Post Office and Internal Portal used by the Portuguese Air Force. Using a case study methodology, this study portrays the elimination of waste and the optimization of existing human and financial resources. After the implementation in 2015, it is still possible now to verify that there is some resistance to change, and the fact that we are dealing with a hierarchical organization justifies this disadvantage. The implementation and operation of all services in their entirety allowed the optimization of resources and the simplification of processes, resulting in the elimination of duplicate tasks.