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991.
The aim of this work is to be a useful instrument for helping finance practitioners on the selection of suitable mutual fund portfolios. The portfolio selection problem is characterized by imprecision and/or vagueness inherent in the required data and more generally, in the context where investors have to make decisions. In order to mitigate these problems, a three stage model has been proposed based on a multi-index model and considering several market scenarios described in an imprecise way by an expert. The proposed fuzzy model allows the Decision Maker to select, by means of an outranking method, a suitable portfolio taking into account the uncertainty related to the market scenarios and the imprecision and/or vagueness associated with the model data.  相似文献   
992.
In this paper we develop a segmentation scheme for digital images based upon an iterative binary coloring technique that takes into account changing behavior of adjacent pixels. The output is a hierarchical structure of images which allows a better understanding of complex images. In particular, we propose two algorithms that should be considered as image preprocessing techniques.  相似文献   
993.
Literature on ambidexterity emphasizes the need for both exploration and exploitation. Large firms usually choose to implement structural ambidexterity to separate both activities. We here focus on an extreme case of such structural partitioning implemented as a secret skunkworks project in a large French automotive company. A qualitative survey using both primary and secondary data shows that the major basic and initial characteristics of a skunkworks (i.e. secrecy, urgency, and autonomy) created favorable conditions for the technological exploration. However, exploitation failed due to precisely those same characteristics coupled with the fact that the project did not respond to a specific market demand: The skunkworks suffered from what we call the "Robinson Crusoe effect." We therefore contribute to the literature on skunkworks, which have remained understudied in the academic literature, as well as on ambidexterity, by showing how the interrelation between different factors is crucial for structural ambidexterity to be successful  相似文献   
994.
995.
Turnover turned over: an expanded and positive perspective   总被引:4,自引:0,他引:4  
The negative impact of turnover is well documented in the literature. This paper examines turnover with a unique, positive focus. Turnover is reviewed, not only from the standpoint of the organizational theorist, but with economic, sociological, and psychological/social psychological perspectives. Often ignored benefits of turnover are noted.  相似文献   
996.
997.
Noel D Uri 《Omega》1977,5(4):463-472
It has recently been shown that the Box-Jenkins approach to forecasting time series is superior to an econometric approach over a relatively short horizon. The results here support this contention. A combination of the two approaches, however, proves to be clearly superior to either one separately. By taking account of changes in economic and weather related variables in a time series model, improved forecasts are obtained.  相似文献   
998.
Much recent discussion of corporate social responsibility has concerned operationality. Many activities subsumed under corporate social responsibility can be shown to be public or partially public goods. The theory of public goods can clarify and explain some complex problems of operationalizing the social responsibility doctrine. An examination of philanthropy provides some behavioral applications.  相似文献   
999.
One of the most difficult problems in teaching social services has to do with the development of an analytic framework for an understanding of the delivery of social services within the community. This paper examines a particular systems framework that allows the student to conceptualize and evaluate what services are being delivered, what specific inputs and connections of agency with community act to produce this service, and what changes in the system may be possible. The model allows ready connection with practice, policy, and research components of the curriculum.  相似文献   
1000.

Protective capacity is the 'extra' capacity placed at non-bottleneck resources to absorb random disruptions in planned levels of performance so that the bottleneck resource continues to be effectively utilized. A full factorial experiment with a simulation model was conducted to explore issues associated with the quantity and location of processing variance in a five-station manufacturing cell. The cell's performance was measured using both mean flow time ( MFT ) and bottleneck shiftiness ( SHIFT ) for 3 patterns of variance for the non-bottlenecks at 5 different levels of variation. In order to investigate the importance of the quantity of added capacity on the variation both a low level of protective capacity (10%) and a high level (50%) were considered. The results indicate that having the higher variation work centres close to the bottleneck provides reduced MFT and SHIFT . The performance measures improved at both the low and high setting of protective capacity.  相似文献   
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