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Many researchers have explored the advantages of modular product design, its design methods and its effects on product performance. Modular design is, for example, required for product platform, mass customization and postponement in order to achieve greater product variety and differentiation. However, a few empirical studies explicitly examine how to coordinate modular product design in a managerial way. This paper addresses it by conducting multiple case studies with six companies which have successfully adopted modular product design for five years. Seven critical factors are explored in the management of modular product design. These are pre-defined product advantage, selectively used design rules, module definition, system integration, technological newness, internal communication, and supplier and customer involvement. While most of the literature studies the technical dimension of modular design within a firm, this study focuses on the managerial side across the supply chain. It gives new insights on how to manage modular product design and proposes future research opportunities.  相似文献   
43.
Use of similar or identical antibiotics in both human and veterinary medicine has come under increasing scrutiny by regulators concerned that bacteria resistant to animal antibiotics will infect people and resist treatment with similar human antibiotics, leading to excess illnesses and deaths. Scientists, regulators, and interest groups in the United States and Europe have urged bans on nontherapeutic and some therapeutic uses of animal antibiotics to protect human health. Many regulators and public health experts have also expressed dissatisfaction with the perceived limitations of quantitative risk assessment and have proposed alternative qualitative and judgmental approaches ranging from "attributable fraction" estimates to risk management recommendations based on the precautionary principle or on expert judgments about the importance of classes of compounds in human medicine. This article presents a more traditional quantitative risk assessment of the likely human health impacts of continuing versus withdrawing use of fluoroquinolones and macrolides in production of broiler chickens in the United States. An analytic framework is developed and applied to available data. It indicates that withdrawing animal antibiotics can cause far more human illness-days than it would prevent: the estimated human BENEFIT:RISK health ratio for human health impacts of continued animal antibiotic use exceeds 1,000:1 in many cases. This conclusion is driven by a hypothesized causal sequence in which withdrawing animal antibiotic use increases illnesses rates in animals, microbial loads in servings from the affected animals, and hence human health risks. This potentially important aspect of human health risk assessment for animal antibiotics has not previously been quantified.  相似文献   
44.
Models of Neurotoxicity: Extrapolation of Benchmark Doses in Vitro   总被引:4,自引:0,他引:4  
In risk assessment, no observed exposure level (NOAEL) and benchmark dose (BMD) are usually derived either from epidemiological studies in humans or from animal experiments. In many in vitro studies, concentration-effect/response curves have been analyzed using different mathematical models finalized to the identification of EC50. In the present article, we propose a model to fit dose-response curves in vitro. The BMD approach has been used to compare the cell viability (MIT assay) of different rat (C6 and PC12, glial and neuronal, respectively) and human cell lines (D384 and SK-N-MC, glial and neuronal, respectively) after 24-hour exposure to the following neurotoxic substances: manganese chloride (MnCl2), methyl-mercury (Me-Hg), and the enantiomers of styrene oxide (SO). For all rat and human cell lines, the potency of the examined compounds was: MnCl2 < S-SO < R-SO < Me-Hg. A preliminary comparison with in vivo toxicity data for these substances gave rise to consistent results. Whereas a reasonable agreement between in vitro and in vivo data has been found for Mn and styrene oxide, a wide scatter of LOAEL has been reported for Me-Hg and these appear to be either much higher or lower than the BMD for the MIT assay we observed in vitro.  相似文献   
45.
Bridging Scholarship in Management: Epistemological Reflections   总被引:1,自引:1,他引:1  
If the relevance gap in management research is to be narrowed, management scholars must identify and adopt processes of inquiry that simultaneously achieve high rigour and high relevance. Research approaches that strive for relevance emphasize the particular at the expense of the general and approaches that strive for rigour emphasize the general over the particular. Inquiry that attains both rigour and relevance can be found in approaches to knowledge that involve a reasoned relationship between the particular and the general. Prominent among these are the works of Ikujiro Nonaka and John Dewey. Their epistemological foundations indicate the potential for a philosophy of science and a process of inquiry that crosses epistemological lines by synthesizing the particular and the general and by utilizing experience and theory, the implicit and the explicit, and induction and deduction. These epistemologies point to characteristics of a bridging scholarship that is problem-initiated and rests on expanded standards of validity. The present epistemological reflections are in search of new communities of knowing toward the production of relevant and rigorous management knowledge.  相似文献   
46.
In this paper we estimate a bargaining model of government formation in parliamentary democracies. We use the estimated structural model to conduct constitutional experiments aimed at evaluating the impact of institutional features of the political environment on the duration of the government formation process, the type of coalitions that form, and their relative stability.  相似文献   
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48.
How can we best allocate limited defensive resources to reduce terrorism risks? Dillon et al.'s Antiterrorism Risk-Based Decision Aid (ARDA) system provides a useful point of departure for addressing this crucial question by exhibiting a real-world system that calculates risk reduction scores for different portfolios of risk-reducing countermeasures and using them to rank-order different possible risk mitigation alternatives for Navy facilities. This comment points out some potential limitations of any scoring system that does not take into account risk externalities, interdependencies among threats, uncertainties that are correlated across targets, and attacker responses to alternative allocations of defensive resources. In at least some simple situations, allocations based on risk reduction scores and comparisons can inadvertently increase risks by providing intelligent attackers with valuable information, or they can fail to reduce risks as effectively as nonscoring, optimization-based approaches. These limitations of present scoring methods present exciting technical challenges and opportunities for risk analysts to develop improved methods for protecting facilities and infrastructure against terrorist threats.  相似文献   
49.
Modular product design and internal integration are commonly adopted by manufacturers to improve operational performance. A number of studies argue that the adoption of product modularity significantly alters organization design, which affects the impact of internal integration on competitive capabilities. This paper thus aims to empirically explore the individual effects as well as interaction effects of product modularity and internal integration on competitive capabilities. The competitive capabilities studied in this paper include product innovativeness, low price, product quality, delivery, flexibility and customer services. After analysing the data from 251 Hong Kong manufacturers through moderated multiple regression analysis, the study found that better internal integration can significantly improve product innovativeness, product quality, delivery, flexibility and customer services, while a high level of product modularity enhances product innovativeness, flexibility and customer services. More importantly, the study shows that internal integration and product modularity can interact to improve product innovativeness and product quality. These results enhance our understanding of the interaction of product design and organizational coordination.  相似文献   
50.
Objective. This article uses Cox proportional hazards models to explain departures from the U.S. Courts of Appeals from 1954–2004. I argue that reforms to pension eligibility and financial incentives in 1984 extended opportunities for voluntary departures and strategic behavior, and that reasons for quitting (whether political, personal, or institutional) differed among types of departures and over time. Methods. The data represent all judge‐years from 1954–2004. Both the full period and 1954–1983 and 1984–2004 subperiods are examined. Results. The effects of political factors are limited to partial retirements and suggest judges' recognition of contentious confirmation politics since the 1980s. Personal and institutional variables dominate outright departures. Conclusions. Explanations for departures from the circuit bench differ both by type and over time. Scholars and policymakers should refine arguments regarding judicial turnover and its causes.  相似文献   
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