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101.
102.
General Motors had enjoyed global operations that were based on exports, acquisitions, joint ventures and strategic alliances throughout the 20th century. Its global-programme strategy appeared assured. However, the carmaker came unstuck when it came to creating a large-scale collaborative effort involving its own internal units. The Delta Small Car Program, involving three fully internal GM units, was terminated after its goals failed to materialise. The carmaker’s long-standing cultural tradition of autonomy for its units was what made collaboration between them difficult. We examine this GM global programme, placing it in its historical context. Our primary database consists of the perceptions and experiences offered to us by a cross-section of programme participants. By examining partner integration at the working level, we identify insights and offer recommendations pertaining to venture structure and dynamics and their role in venture success.  相似文献   
103.
Let G=(V,E) be a graph. A set of vertices S?V is a total restrained dominating set if every vertex is adjacent to a vertex in S and every vertex of $V-\nobreak S$ is adjacent to a vertex in V?S. The total restrained domination number of G, denoted by γ tr (G), is the smallest cardinality of a total restrained dominating set of G. A support vertex of a graph is a vertex of degree at least two which is adjacent to a leaf. We show that $\gamma_{\mathit{tr}}(T)\leq\lfloor\frac{n+2s+\ell-1}{2}\rfloor$ where T is a tree of order n≥3, and s and ? are, respectively, the number of support vertices and leaves of T. We also constructively characterize the trees attaining the aforementioned bound.  相似文献   
104.
The risk perception research is widely focused on children as targets of risk. To date, very few studies have consulted with the impacted group to assess the perceptions of risk associated with the exposures of interest. Much less research has investigated the experiences of children at risk for anaphylaxis, their concerns, and the psychosocial stresses associated with risk. The present study explores the perceptions and experiences of Ontario students with anaphylaxis, and their parents regarding school as a safe place in order to inform school policy around risk management and coping. A “child‐centered” analytical framework incorporating illustrative techniques within interpretative analysis is outlined. Five prominent themes: (a) social and environmental barriers to safety, (b) coping strategies, (c) emotional burden of responsibility, (d) balance of responsibility (transitions), and (e) redefining “normal” are discussed. Results found that “child‐centered” techniques empowered children in a process that is meaningful and relevant to their lives. A preliminary framework for understanding what risk means to children highlighted the differences in how they cope in the public sphere of school.  相似文献   
105.
Mixed Levels of Uncertainty in Complex Policy Models   总被引:3,自引:0,他引:3  
The characterization and treatment of uncertainty poses special challenges when modeling indeterminate or complex coupled systems such as those involved in the interactions between human activity, climate and the ecosystem. Uncertainty about model structure may become as, or more important than, uncertainty about parameter values. When uncertainty grows so large that prediction or optimization no longer makes sense, it may still be possible to use the model as a behavioral test bed to examine the relative robustness of alternative observational and behavioral strategies. When models must be run into portions of their phase space that are not well understood, different submodels may become unreliable at different rates. A common example involves running a time stepped model far into the future. Several strategies can be used to deal with such situations. The probability of model failure can be reported as a function of time. Possible alternative surprises can be assigned probabilities, modeled separately, and combined. Finally, through the use of subjective judgments, one may be able to combine, and over time shift between models, moving from more detailed to progressively simpler order-of-magnitude models, and perhaps ultimately, on to simple bounding analysis.  相似文献   
106.
107.
This study examines perception of various business practices of Russian and American managers. Using data collected from 136 Russian managers and 252 American managers we found that cross-national differences account for many differences between perceptions of business practices. Implications for managerial practice are discussed. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
108.
European food retailers have increased their scale and scope while concentrating sales into large stores. Strategic implications include the need for scale to compete and organisational relationships to move from supply push to demand pull retailing. Consequences are different for private label and for branded manufacturers, who must respond to the demands of retail supply chains whilst retaining control of product development. Further concentration in both sectors is likely. Consumers are more mobile, but more captive to the retailer in store. Public policy makers are challenged to find new measures of retail power and both allow for innovation and ensure equitable shopping opportunities.  相似文献   
109.
In this paper, we propose a spatial model for the initiation of cracks in the bone cement of hip replacement specimens. The failure of hip replacements can be attributed mainly to damage accumulation, consisting of crack initiation and growth, occurring in the cement mantle that interlocks the hip prosthesis and the femur bone. Since crack initiation is an important factor in determining the lifetime of a replacement, the understanding of the reasons for crack initiation is vital in attempting to prolong the life of the hip replacement. The data consist of crack location coordinates from five laboratory experimental models, together with stress measurements. It is known that stress plays a major role in the initiation of cracks, and it is also known that other unmeasurable factors such as air bubbles (pores) in the cement mantle are also influential. We propose an identity-link spatial Poisson regression model for the counts of cracks in discrete regions of the cement, incorporating both the measured (stress), and through a latent process, any unmeasured factors (possibly pores) that may be influential. All analysis is carried out in a Bayesian framework, allowing for the inclusion of prior information obtained from engineers, and parameter estimation for the model is done via Markov chain Monte Carlo techniques.  相似文献   
110.
The success of interventions designed to address important issues in social and medical science is best addressed by randomized experiments. With human beings there are often complications, however, such as noncompliance and missing data. Such complications are often addressed by statistically invalid methods of analysis, in particular, intention-to-treat and per-protocol analyses. Here we address these two complications using a statistically valid approach based on principal stratification with a fully Bayesian analysis. This analysis is applied to a randomized trial of a potentially important intervention designed to reduce the transmission of bacterial colonization between mothers and their infants through vaginal delivery in South Africa: the Prevention of Perinatal Sepsis (PoPs).  相似文献   
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