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881.
882.
Strategy research has often taken a product-centered perspective. When firms compete in environments characterized by accelerating product life cycles, mass customization, and technological discontinuities, a product-centered perspective on strategy may help explain a firm’s current competitive advantage. However, this perspective adds little guidance in making strategies that create competitive advantage in the future. In this paper, we present a perspective in which dynamic environments require firms to focus on (1) building market-driven, technological, and integration competencies, not a stream of product improvements, and (2) decoupling these competencies from current products in order to create and exploit new opportunities. We discuss the perspective of products as a temporary integration of market and technology trajectories. Research propositions are presented and future implications are discussed.  相似文献   
883.
We investigate lifting, i.e., the process of taking a valid inequality for a polyhedron and extending it to a valid inequality in a higher dimensional space. Lifting is usually applied sequentially, that is, variables in a set are lifted one after the other. This may be computationally unattractive since it involves the solution of an optimization problem to compute a lifting coefficient for each variable. To relieve this computational burden, we study sequence independent lifting, which only involves the solution of one optimization problem. We show that if a certain lifting function is superadditive, then the lifting coefficients are independent of the lifting sequence. We introduce the idea of valid superadditive lifting functions to obtain good aproximations to maximum lifting. We apply these results to strengthen Balas' lifting theorem for cover inequalities and to produce lifted flow cover inequalities for a single node flow problem.  相似文献   
884.
Generational analysis considers the differences in world view and attitude between various generations of Americans and uses this information to develop insight and business strategies. The much discussed generation gap between the Baby Boomers and their elders during the 1960s and 1970s is equaled or exceeded by the differences between Generations X and Y and the Boomers. Generation X physicians will be coming into practice over the next two decades. Successful medical leaders must understand Gen-Xers to create clinical environments that meet their unique needs and concerns. This article describes some of the philosophical and attitudinal differences between the generations and what these differences may mean to the future of medicine and health care organizations.  相似文献   
885.
A risk assessment was conducted to determine the likelihood of certain health risks resulting from exposure to soils and food crops contaminated with polychlorinated biphenyl (PCBs). PCBs have contaminated soils, river sediments, and air in the past as a result of industrial activities at a capacitor plant located in the City of Serpukhov, Russian Federation. This risk assessment and suggestions for remediation are designed to aid in decision-making efforts by a joint Russian-American research team developing a community, national, and international response to industrial contamination. Bobovnikova et al. (The Science of the Total Environment 139/140, 357-364, [1993]) have reported that PCBs are elevated in soils and sediments, breast milk, and locally grown foods in the Serpukhov area. Data from these and other investigators have been used in this risk assessment to calculate a potential cancer risk resulting from exposure to PCBs. Our assessment indicates that members of the local population may be at increased risk of cancer, and possibly other adverse health effects, as a result of PCB contamination of their environment. Because previously unassessed environmental contamination is a common problem in the former Soviet Republics, as well as many other areas of the world, we believe this type of evaluation, using known methods, can serve as a model for assessment efforts in other parts of the globe and result in remediative efforts in regions constrained by faltering economies.  相似文献   
886.
This article presents arguments for the development of generic assessment endpoints for ecological risk assessment. Generic assessment endpoints would be ecological entities and attributes that are assumed to be worthy of protection in most contexts. The existence of generic assessment endpoints would neither create a requirement that they be used in every assessment nor preclude the use of other assessment endpoints. They would simply be a starting point in the process of identifying the assessment endpoints for a particular assessment. They are needed to meet legal mandates, to provide a floor for environmental degradation, to provide some consistency in environmental regulation, as exemplars for site- or project-specific assessment endpoints, to allow development of methods and models, to give risk managers the courage to act, for screening and site-independent assessments, to support environmental monitoring, to facilitate communication, and to avoid paralysis by analysis. Generic assessment endpoints should include not only a list of entities and attributes, but also explanations of each endpoint, guidance on their use and interpretation, and measures and models that could be used to estimate them.  相似文献   
887.
Richard L. Reece, MD, interviewed Robert J. Hudson, MD, on April 24, 2000 to discuss his experiences as a physician executive who has made the career transition from practicing physician to managed care executive to biotech entrepreneur. Along the way, he's hired and fired others, and been fired himself. Painful as it is, many physician executives' career realities include being fired. Organizations, after all, are living organizations--they grow, wither, and molt. And as they molt, organizations shed and regrow new skin. What do physician executives do when they've been fired? They go through their own cycle and retreat, reflect, and re-emerge, often reinventing themselves as they go. An essential part of this process is looking within to plumb likes and dislikes, strengths and weaknesses, nightmares and dreams, and positive and negative experiences. For most executives, out of these experiences has come a circle of friends and a Rolodex. Start by reaching out to the circle, by going through your Rolodex, and you can broadcast the news of your rebirth.  相似文献   
888.
The turbulent state of health care and the rapid changes that show no sign of abating point to many career-related challenges for physician executives. How can you predict the impact of these changes on your career? What measures can be taken to prevent any negative impact of change? And how can you prevail when dealt a negative blow like job loss? The signs that foreshadow the unraveling of a physician executive's career are described. The warning signs are: Not keeping up with change, losing your influence; getting negative feedback; turning your "concerns" into complaints; the economy working against you; and being blindsided because we think leaders operate logically. Being proactive puts more control in your hands and leaves less to chance. You can prevent being blindsided if you: develop your people skills; get comfortable and involved with e-business; stay abreast of health care trends; pick up the pace; and develop "You, Inc." There is a final component to prevailing over adverse circumstances--find your work-related passion and apply it to your career.  相似文献   
889.
This paper presents an overview of the literature on union commitment. The aim is to survey the main approaches, findings and implications of the research. The nature and dimensionality of union commitment are examined, and the antecedents and consequences of union commitment are discussed in detail, including a review of the implications for union participation. There is also a discussion of the possibility of dual commitment to union and employer, and of the 'multiple constituencies' view of commitment. An attempt is made to link the union commitment findings to the wider industrial relations literature on, for example, why people join unions and the 'union renewal' thesis. The article concludes by discussing the implications of the literature for union–management relationships and for unions themselves, and with some suggestions for future research.  相似文献   
890.
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