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981.
This paper considers the NP-hard graph problem of determining a maximum cardinality subset of vertices inducing a k-regular subgraph. For any graph G, this maximum will be denoted by α k (G). From a well known Motzkin-Straus result, a relationship is deduced between α k (G) and the independence number α(G). Next, it is proved that the upper bounds υ k (G) introduced in Cardoso et al. (J. Comb. Optim., 14, 455–463, 2007) can easily be computed from υ 0(G), for any positive integer k. This relationship also allows one to present an alternative proof of the Hoffman bound extension introduced in the above paper. The paper continues with the introduction of a new upper bound on α k (G) improving υ k (G). Due to the difficulty of computing this improved bound, two methods are provided for approximating it. Finally, some computational experiments which were performed to compare all bounds studied are reported.  相似文献   
982.
In previous work we established a closed-form optimal stocking strategy for an EPQ model with partial backordering at a constant rate β. Here we extend this work to allow for the possibility that the percentage of demand backordered will increase when production starts again. We show how our previous model can be adapted to find the optimal decision variable values for this new assumption and develop the condition that the initial value of β must meet for partial backordering to be optimal.  相似文献   
983.
We develop a multi-theoretic approach, drawing on economic, institutional, managerial power and social comparison literatures to explain the role of the external compensation consultant in the top management pay setting institutional field. Taking advantage of recent disclosure requirements in the UK, we collect data on compensation consultant use in 232 large companies. We show that consultants are a prevalent part of the CEO pay setting scene, and document evidence of all advisor use. Our econometric results show that consultant use is associated with firm size and the equity pay mix. We also show that CEO pay is positively associated with peer firms that share consultants, with higher board and consultant interlocks, and some evidence that where firms supply other business services to the firm, CEO pay is greater.  相似文献   
984.
要保持竞争力,企业必须在人员管理方面采取大幅变革当婴儿潮一代临近传统上的退休年龄,具有前瞻思维的企业正加大对领导力发展与继任规划的投入。他们着眼于加强人才储备:让企业的青  相似文献   
985.
A powerful practical solution is by far the most desired output when making decisions under the realm of uncertainty on any safety-critical marine or offshore units and their systems. With data and information typically being obtained incrementally, adopting Bayesian network (BN) is shown to realistically deal with the random uncertainties while at the same time making risk assessments easier to build and to check. A well-matched methodology is proposed to formalize the reasoning in which the focal mechanism of inference processing relies on the sound Bayes's rule/theorem that permits the logic. Expanding one or more influencing nodal parameters with decision and utility node(s) also yields an influence diagram (ID). BN and ID feasibility is shown in a marine evacuation scenario and that of authorized vessels to floating, production, storage, and offloading collision, developed via a commercial computer tool. Sensitivity analysis and validation of the produced results are also presented.  相似文献   
986.
To reduce consumer health risks from foodborne diseases that result from improper domestic food handling, consumers need to know how to safely handle food. To realize improvements in public health, it is necessary to develop interventions that match the needs of individual consumers. Successful intervention strategies are therefore contingent on identifying not only the practices that are important for consumer protection, but also barriers that prevent consumers from responding to these interventions. A measure of food safety behavior is needed to assess the effectiveness of different intervention strategies across different groups of consumers. A nationally representative survey was conducted in the Netherlands to determine which practices are likely conducted by which consumers. Participants reported their behaviors with respect to 55 different food-handling practices. The Rasch modeling technique was used to determine a general measure for the likelihood of an average consumer performing each food-handling behavior. Simultaneously, an average performance measure was estimated for each consumer. These two measures can be combined to predict the likelihood that an individual consumer engages in a specific food-handling behavior. A single "food safety" dimension was shown to underlie all items. Some potentially safe practices (e.g., use of meat thermometers) were reported as very difficult, while other safe practices were conducted by respondents more frequently (e.g., washing of fresh fruit and vegetables). A cluster analysis was applied to the resulting data set, and five segments of consumers were identified. Different behaviors may have different effects on microbial growth in food, and thus have different consequences for human health. Once the microbial relevance of the different consumer behaviors has been confirmed by experiments and modeling, the scale developed in the research reported here can be used to develop risk communication targeted to the needs of different consumer groups, as well as to measure the efficacy of different interventions.  相似文献   
987.
Zusammenfassung  Zur Bewertung von Investitionsprojekten mit mehrperiodigen Zahlungen werden die erwarteten Zahlungen mit geeigneten Kapitalkosten diskontiert. In dieser Arbeit wird gezeigt, dass die erwarteten einperiodigen Renditen nur unter bestimmten Annahmen die geeigneten Kapitalkosten darstellen. Wenn zwischen den einperiodigen Renditen Autokorrelation auftritt, ist ein zus?tzlicher Korrekturterm bei der Ermittlung der Kapitalkosten zu berücksichtigen. Im Falle unkorrelierter Renditen entspricht der stochastische Prozess der Renditen dem Prozess der Risikoaufl?sung.
Summary  In this paper it is argued that the discount rates used for the computation of the present values of an investment project with cash-flows to be realized over several years have to be adjusted when the one-period returns of the investment project are autocorrelated. The formula of the correct discount rate is deduced. In the case of uncorrelated returns of the investment, the stochastic process of the returns and of the cost of capital are closely related to the process of the arrival of information over time.
Ich danke zwei anonymen Gutachtern für wertvolle Verbesserungsvorschl?ge an einer früheren Version des Aufsatzes sowie dem Verein zur F?rderung der Zusammenarbeit zwischen Lehre und Praxis am Finanzplatz Hannover e.V. für seine Unterstützung.  相似文献   
988.
Constructive-developmental theory is a stage theory of adult development that focuses on the growth and elaboration of a person's ways of understanding the self and the world. In this article we review how the constructive-developmental frameworks of Kegan [Kegan, R. (1982). The evolving self: Problem and process in human development. Cambridge, MA: Harvard University Press], Torbert [Torbert, W. R. (1987). Managing the corporate dream: Restructuring for long-term success. Homewood, IL: Dow Jones-Irwin.], and Kohlberg [Kohlberg, L. (1969). Stage and sequence: The cognitive developmental approach to socialization. In D. Goslin (Ed.), Handbook of socialization: Theory and research. New York: Rand McNally] have been applied in the theoretical and empirical literature on leadership and management. Although the literature has produced a number of propositions, the notion that a leader's order of development should impact his or her leadership effectiveness or managerial performance has generated the most research. We found mixed support for this proposition as well as a number of limitations in the research in general. To have a greater impact on the leadership field, constructive-developmental theory needs to generate more robust research, to link more clearly with on-going streams of leadership research, and to explore the contribution of aspects of the theory beyond individual order of development.  相似文献   
989.
990.
The proximity concept is used in many different ways in the literature. These dimensions of proximity are, however, defined and measured in many different (sometimes even contradictory) ways, show large amounts of overlap, and often are under‐ or over‐specified. The goal of this paper is to specify the different dimensions of proximity relevant in inter‐organizational collaboration more precisely and to provide definitions of these dimensions. The research presented contributes to reducing the ambiguity of the proximity concept as used in the literature. Based on the above, the following research question is addressed in this paper: ‘Which dimensions of proximity are relevant in inter‐organizational collaboration and how are they defined?’ A systematic literature review is presented in order to disentangle the dimensions of the proximity concept. Based on this literature review, three dimensions of proximity relevant in inter‐organizational collaboration are distinguished: geographical proximity, organizational proximity and technological proximity. Examples (case studies) from the literature are used to illustrate the current conceptual ambiguity as well as to clarify how the proposed dimensions of proximity reduce this conceptual ambiguity.  相似文献   
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