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971.
972.
Kjetil Fagerholt Marielle Christiansen Lars Magnus Hvattum Trond A.V. Johnsen Thor J. Vabø 《Omega》2010
This paper presents a decision support methodology for strategic planning in tramp and industrial shipping. The proposed methodology combines simulation and optimization, where a Monte Carlo simulation framework is built around an optimization-based decision support system for short-term routing and scheduling. The simulation proceeds by considering a series of short-term routing and scheduling problems using a rolling horizon principle where information is revealed as time goes by. The approach is flexible in the sense that it can easily be configured to provide decision support for a wide range of strategic planning problems, such as fleet size and mix problems, analysis of long-term contracts and contract terms. The methodology is tested on a real case for a major Norwegian shipping company. The methodology provided valuable decision support on important strategic planning problems for the shipping company. 相似文献
973.
Managers and supervisors are thought to affect their followers' attitudes and behaviour. Within leadership research, behaviour of leaders and managers is usually considered as the independent variable whilst followers' reactions are considered the dependent variable. In this study, we reverse this order and investigate the degree to which the evaluation of leadership is a result of followers' perceptions and attributions. In order to corroborate and extend previous experimental research, a field study was conducted to analyse the influence of followers' personality and perceived leader personality on followers' perception of leadership within an organizational setting. The results provide further evidence that followers' personality influences the perception of transformational leadership and commitment to the supervisor. Moreover, the perception of leaders' personality was related to the perception of leadership and commitment to the supervisor. The finding that the perception of supervisors' personality mediates both the relationship between followers' personality and the perception of leadership and commitment provides support for the similarity hypothesis. Results are discussed in the light of feedback and leader development. 相似文献
974.
This study empirically investigates the safeguarding effect of (1) administrative control, (2) a dominant power position and (3) relational norms, on opportunistic behaviour of suppliers, by means of a survey among 624 information and communication technology professionals in Dutch municipalities. The findings indicate that individual effectiveness of relational norms, particularly in terms of flexibility and solidarity, was most prominent. Administrative control and power did not show a significant impact on supplier opportunism in our sample. Research into the simultaneous use of several safeguards against opportunism generated the finding that different relational norms fortify each other's safeguarding effect. Furthermore, we demonstrate that supplier opportunism is only mitigated by a dominant power position when the buyer does not exploit its favourable position and the buyer does not behave opportunistically. Hence, power seems to have a safeguarding effect only when it is not used. 相似文献
975.
This article is based on a quantitative risk assessment (QRA) that was performed on a radioactive waste disposal area within the Western New York Nuclear Service Center in western New York State. The QRA results were instrumental in the decision by the New York State Energy Research and Development Authority to support a strategy of in‐place management of the disposal area for another decade. The QRA methodology adopted for this first of a kind application was a scenario‐based approach in the framework of the triplet definition of risk (scenarios, likelihoods, consequences). The measure of risk is the frequency of occurrence of different levels of radiation dose to humans at prescribed locations. The risk from each scenario is determined by (1) the frequency of disruptive events or natural processes that cause a release of radioactive materials from the disposal area; (2) the physical form, quantity, and radionuclide content of the material that is released during each scenario; (3) distribution, dilution, and deposition of the released materials throughout the environment surrounding the disposal area; and (4) public exposure to the distributed material and the accumulated radiation dose from that exposure. The risks of the individual scenarios are assembled into a representation of the risk from the disposal area. In addition to quantifying the total risk to the public, the analysis ranks the importance of each contributing scenario, which facilitates taking corrective actions and implementing effective risk management. Perhaps most importantly, quantification of the uncertainties is an intrinsic part of the risk results. This approach to safety analysis has demonstrated many advantages of applying QRA principles to assessing the risk of facilities involving hazardous materials. 相似文献
976.
Travis William Reynolds Ann Bostrom Daniel Read M. Granger Morgan 《Risk analysis》2010,30(10):1520-1538
In 1992, a mental‐models‐based survey in Pittsburgh, Pennsylvania, revealed that educated laypeople often conflated global climate change and stratospheric ozone depletion, and appeared relatively unaware of the role of anthropogenic carbon dioxide emissions in global warming. This study compares those survey results with 2009 data from a sample of similarly well‐educated laypeople responding to the same survey instrument. Not surprisingly, following a decade of explosive attention to climate change in politics and in the mainstream media, survey respondents in 2009 showed higher awareness and comprehension of some climate change causes. Most notably, unlike those in 1992, 2009 respondents rarely mentioned ozone depletion as a cause of global warming. They were also far more likely to correctly volunteer energy use as a major cause of climate change; many in 2009 also cited natural processes and historical climatic cycles as key causes. When asked how to address the problem of climate change, while respondents in 1992 were unable to differentiate between general “good environmental practices” and actions specific to addressing climate change, respondents in 2009 have begun to appreciate the differences. Despite this, many individuals in 2009 still had incorrect beliefs about climate change, and still did not appear to fully appreciate key facts such as that global warming is primarily due to increased concentrations of carbon dioxide in the atmosphere, and the single most important source of this carbon dioxide is the combustion of fossil fuels. 相似文献
977.
Fabio Lopez Chiara Di Bartolo Tommaso Piazza Antonino Passannanti Jörg C. Gerlach Bruno Gridelli Fabio Triolo 《Risk analysis》2010,30(12):1857-1871
International regulatory authorities view risk management as an essential production need for the development of innovative, somatic cell‐based therapies in regenerative medicine. The available risk management guidelines, however, provide little guidance on specific risk analysis approaches and procedures applicable in clinical cell therapy manufacturing. This raises a number of problems. Cell manufacturing is a poorly automated process, prone to operator‐introduced variations, and affected by heterogeneity of the processed organs/tissues and lot‐dependent variability of reagent (e.g., collagenase) efficiency. In this study, the principal challenges faced in a cell‐based product manufacturing context (i.e., high dependence on human intervention and absence of reference standards for acceptable risk levels) are identified and addressed, and a risk management model approach applicable to manufacturing of cells for clinical use is described for the first time. The use of the heuristic and pseudo‐quantitative failure mode and effect analysis/failure mode and critical effect analysis risk analysis technique associated with direct estimation of severity, occurrence, and detection is, in this specific context, as effective as, but more efficient than, the analytic hierarchy process. Moreover, a severity/occurrence matrix and Pareto analysis can be successfully adopted to identify priority failure modes on which to act to mitigate risks. The application of this approach to clinical cell therapy manufacturing in regenerative medicine is also discussed. 相似文献
978.
979.
980.
B.J. Hicks S.J. Culley C.A. McMahon P. Powell 《Journal of Engineering and Technology Management》2010,27(1-2):52-73
The benefits of integrated enterprise-wide information systems (IS), such as Enterprise Resource Planning (ERP) systems, are widely accepted. The implementation of such systems in large organisations is established with many in their second or third generation. However, in small to medium-sized enterprises (SMEs) the maturity and extent of their IS infrastructure is less clear. In engineering SMEs, this infrastructure needs to support not only business processes but also the activities of design and manufacture.In this case study, our goal is to provide a better understanding of current IS infrastructure, the functional elements of IS infrastructure, integration and expenditures are explored in ten engineering SMEs. A model of IS functionality is developed and used to identify and classify functional elements within the firms and to compare and contrast the IS infrastructures. The findings are contrasted with the SME literature and conclusions and implications developed. 相似文献