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231.
Perception of Ecological Risk to Water Environments   总被引:12,自引:1,他引:12  
This paper examines lay and expert perceptions of the ecological risks associated with a range of human activities that could adversely affect water resource environments. It employs the psychometric paradigm pioneered in characterizing perceptions of human health risks, which involves surveys to obtain judgments from subjects about risk items in terms of several important characteristics of the risks. The paper builds on a previous study that introduced ecological risk perception. This second study employs a larger, more diverse sample, a more focused topic area, and comparisons between lay and expert judgments. The results confirm that a small set of underlying factors explain a great deal of variability in lay judgments about ecological risks. These have been termed Ecological Impact, Human Benefits, Controllability , and Knowledge. The results are useful in explaining subjects' judgments of the general riskiness of, and need for regulation of, various risk items. The results also indicate several differences and areas of agreement among the lay and expert samples that point to potential key issues in future ecological risk management efforts for water resources.  相似文献   
232.
On the basis of discussion and analysis during and following an ATSDR science panel on the bioavailability of mercury in soils, it is apparent that the default assumption of 100% relative bioavailability for mercury-contaminated soils is excessively conservative. However, current knowledge does not allow the development of default assumptions or guidelines for determining relative bioavailability of mercury in soils. Until such default assumptions or guidelines can be developed, site-specific assays of bioavailability, preferably using either animal bioassays or validated in vitro techniques, may provide the best approach for estimating soil-mercury bioavailability.  相似文献   
233.
Effective supply chain management (SCM) has become a potentially valuable way of securing competitive advantage and improving organizational performance since competition is no longer between organizations, but among supply chains. This research conceptualizes and develops five dimensions of SCM practice (strategic supplier partnership, customer relationship, level of information sharing, quality of information sharing, and postponement) and tests the relationships between SCM practices, competitive advantage, and organizational performance. Data for the study were collected from 196 organizations and the relationships proposed in the framework were tested using structural equation modeling. The results indicate that higher levels of SCM practice can lead to enhanced competitive advantage and improved organizational performance. Also, competitive advantage can have a direct, positive impact on organizational performance.  相似文献   
234.
The purpose of ISO 9001:2000 Quality Management System (QMS) is to provide businesses with a model to grow systematically while assuring the quality of their products. The validity of ISO 9001:2000 QMS stems, largely, from the fact that the best minds worldwide have contributed to its development and maintenance, and the fact that many companies have reported real business gains because of its implementation. Unfortunately, many small businesses fail to survive due to the absence or lack of adequate system for managing quality. An obvious recommendation would be to implement ISO 9001:2000 QMS. Nevertheless, small businesses often cite lack of resources and time as the main reasons for not implementing ISO 9001:2000 QMS.  相似文献   
235.
This paper presents findings of a survey on manufacturing strategy practices adopted by the Indian machinery manufacturing companies (IMMC). Based on the survey, three companies have been selected for detailed case studies. Their experiences in the manufacturing strategy process are analyzed. Although the companies represented diversity in terms of product type, sales volume, and geographic location, they share several commonalties including use of advanced manufacturing technologies and use of several improvement techniques. The process of strategy formulation varied among the companies in terms of participants, complexity and degree of formalization. Competitive priorities, order winners and critical success factors are also identified for these companies. Based on strategic manufacturing issues, manufacturing competence index and business performance index for the companies has been worked out.  相似文献   
236.
Many theories on organizational change depart from the assumption of change for the better, that is, change in order to gain a stronger position in relation to its competitors, to become more effective or efficient, or at least to improve the organization. It is our idea that the theories developed on this basis are biased. Contrasting to this dominant approach, this article gives a longitudinal analysis of the development in an organization in decline. It is directed at explaining the downfall of a Dutch province. In the medieval empire of Charlemagne it was one of the most powerful duchies of Europe. Later it became one of the seven provinces in the powerful Dutch Republic, and nowadays it has lost nearly all its tasks and functions. Departing from neo-institutional theory this paper seeks the major causes for this downfall and specifies some of the relations in the theoretical model of punctuated equilibrium. It concludes that the historical institutional dynamics can be seen as a self-enforcing process in which punctuations can be explained by the increasing distance between individual preferences within the organization, and the pressures originating from developments in the environment.Dr. M.S. de Vries is professor in Public Administration at the Radboud University Nijmegen. Address: Thomas van Aquinostraat 5 (room 5.1.56). P.O. Box 9108, 6500 HK Nijmegen, The Netherlands, tel;++31 24 3615691.  相似文献   
237.
We examine the impact of firm-level governance structure on the innovation and internationalization strategies of emerging market firms. We propose that in the case of emerging market firms, governance is a response to the prevailing institutional environment and affects the innovation and internationalization strategies of firms. Based on a longitudinal sample of 16,337 firm-year observations of Indian listed firms over a year time period from 2002 to 2009, we find a positive effect of family ownership and group affiliation on R&D intensity and new foreign investments. Institutional ownership also positively affects new foreign investments, but has no effect on R&D intensity. Further, we find that R&D intensity interacts with family ownership, institutional ownership and group affiliation in affecting new foreign investments.  相似文献   
238.
In the production planning and control of discrete-parts manufacture, aggregation of parts into families, on the basis of similarity, is carried out to ease both long-horizon planning and short-horizon scheduling. Additional advantages are related to those of group technology (GT), such as simplifying the flow of parts and tools and reducing both set-up and production costs. The problem of formally forming part families is presented and discussed. Previous work is reviewed and assessed. Two solution approaches, one based on a location model, the other on simulated annealing, are presented and compared along with test results. The location formulation, which results in an integer programming model solved by Lagrangian relaxation, proved capable of producing solutions of excellent quality, but only for relatively small problem instances. In contrast, simulated annealing, which is a general heuristic approach to combinatorial optimization, produced solutions of comparable quality and could handle realistically large problem instances. However, careful design of the simulated annealing algorithm is crucially important. An effective design is presented.  相似文献   
239.
Schoen R  Landale NS  Daniels K 《Demography》2007,44(4):807-820
Using the first (1995) and third (2001-2002) waves of the Add Health survey, we examine women 's family transitions up to age 24. Only a third of all women marry, and a fifth of those marriages dissolve before age 24. Three out of eight women have afirst birth, with a substantial majority of those births outside of marriage: 66% for whites, 96% for blacks, and 72% for Mexican Americans. Cohabitation is the predominant union form; 59% of women cohabit at least once by age 24. Most cohabitations are short lived, with approximately one in five resulting in a marriage. We summarize the family and relationship experience of women up to age 24 in terms offour categories, each accounting for roughly a quarter of all women. Category 1 has the women who remain single nonparents. Category 2 has the early marriers, women whose marriage is not preceded by a first birth. Category 3 has those who become single parents. Category 4 has the women who cohabit at least once, but who do not marry or have a birth by age 24. The strictly ordered transitions of the 1950s are long gone and have been replaced by a variety of paths to adulthood.  相似文献   
240.
Black is not always black. Subtle distinctions in skin tone translate into significant differences in outcomes. Data on more than 15,000 households interviewed during the 1860 US federal census exhibit sharp differences in wealth holdings between white, mulatto, and black households in the urban South. We document these differences, investigate relationships between wealth and recorded household characteristics, and decompose the wealth gaps to examine the returns to racial characteristics. The analysis reveals a distinct racial hierarchy. Black wealth was only 20% of white wealth, but mulattoes held nearly 50% of whites’ wealth. This advantage is consistent with colourism, the favouritism shown to those of lighter complexion.
Christopher S. RuebeckEmail:
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