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21.
九、功能分析RCM研究的主要目标是保证系统能完成设计的功能,这种功能只有按生产工序所规定的操作水平加工才能实现。功能分析的目的是确定由系统和子系统所完成的主要功能和辅助功能。RCM研究的第一阶段的合乎逻辑的一项任务是有关系统功能的详细分类。首项任务就是功能分析。  相似文献   
22.
A method of combining survey data and Dairy Herd Improvement Association (DHIA) records to achieve low cost farm trials is presented. Farm trials and surveys of current practices and production responses are useful to identify yield gaps between expectations predicted from experimental findings and actual field results. Different management schemes can be ranked using subjective probabilities and stochastic dominance to enhance successful implementation of research findings and to increase the feedback between researchers, extension workers, and producers. A survey of current masitis control practices and expected milk yield response is the example. Combining survey results with DHIA records allowed estimating the relationship between somatic cell counts (SCC) and milk yield. Eliciting beliefs about the relationship between SCC and milk yield showed that producers agreed with predictions from the statistical model. Subjective probabilities about SCC and mastitis control practices showed that our sample of experts and producers consistently ranked the different practices but extension agents had no consensus about the the most or least effective ones.  相似文献   
23.
Transition patterns from school to work differ considerably across OECD countries. Some countries exhibit high youth unemployment rates, which can be considered an indicator of the difficulty facing young people trying to integrate into the labour market. At the same time, education is a time‐consuming process, and enrolment and dropout decisions depend on expected duration of studies as well as on job prospects with and without completed degrees. One way to model entry into the labour market is by means of job‐search models, where the job arrival hazard is a key parameter in capturing the ease or difficulty in finding a job. Standard models of job search and education assume that skills can be upgraded instantaneously (and mostly in the form of on‐the‐job training) at a fixed cost. This paper models education as a time‐consuming process, a concept which we call time‐to‐educate, during which an individual faces the trade‐off between continuing education and taking up a job.  相似文献   
24.
This study investigated the relationship between perception of environmental uncertainty (PEU) and environmental scanning behavior of Chief Executive Officers of 47 manufacturing firms in Nigeria. The results indicated that perceived uncertainty in the environment was significantly higher for the task environment sectors than for the remote environment sectors; and as perceived uncertainty increased in a sector of the environment, scanning frequency and scanning interests also increased. The results were compared with those of prior research in the area of environmental scanning. The results show both the economic and political legal sectors of the environment to be more salient for Nigerian manufacturing executives than for their American counterparts.  相似文献   
25.
This paper studies federal auctions for wildcat leases on the Outer Continental Shelf from 1954 to 1970. These are leases where bidders privately acquire (at some cost) noisy, but equally informative, signals about the amount of oil and gas that may be present. We develop tests of rational and equilibrium bidding in a common values model that are implemented using data on bids and ex post values. We also use data on tract location and ex post values to test the comparative static prediction that bidders may bid less aggressively in common value auctions when they expect more competition. We find that bidders are aware of the "winner's curse" and their bidding is largely consistent with equilibrium.  相似文献   
26.
The general design for the real-time electricity market presented in this paper optimizes and prices both real and reactive power simultaneously in an AC setting, where all assets—generation, load and transmission—are allowed to bid and are financially settled at the locational price times energy consumed or produced. The result is that transmission lines are compensated for both capacity and admittance, providing incentives for efficient operation of transmission-related assets such as FACTS devices, if price-taking behavior is assumed. Losses are incorporated into the design and become an operating cost for transmission. The market design is shown to be revenue neutral and, under some assumptions, nonconfiscatory.   相似文献   
27.
The United States (US) exports more than US$6 billion in agricultural commodities to the European Union(EU) each year, but one issue carries the potential to diminish this trade: use of biotechnology in food production. The EU has adopted more stringent policies towards biotechnology than the US. Understanding differences in European and American policies towards genetically modified (GM) foods requires a greater understanding of consumers’ attitudes and preferences. This paper reports results from the first large‐scale, cross‐Atlantic study to analyse consumer demand for genetically modified food in a non‐hypothetical market environment. We strongly reject the frequent if convenient assumption in trade theory that consumer preferences are identical across countries: the median level of compensation demanded by English and French consumers to consume a GM food is found to be more than twice that in any of the US locations. Results have important implications for trade theory, which typically focuses on differences in specialization, comparative advantage and factor endowments across countries, and for on‐going trade disputes at the World Trade Organization.  相似文献   
28.
This paper investigates whether the macroeconomic performance of a small- open economy depends on the choice of exchange rate regimes. Hong Kong and Taiwan - two economies with many similar macroeconomic characteristics, but different in their choices of exchange rate regimes - provide a good setting to study the relation between the choice of exchange rate regime and macro-economic performance. We examine the basic facts of growth and inflation and the coefficients' stability of their vector autoregression (VAR), as well as cyclical characters of other aggregate variables in Hong Kong and Taiwan. Our empiric finding indicates that macroeconomic performance is not systematically related to exchange rate regimes.  相似文献   
29.
Recent accounting scandals have brought focus on the role of management in financial statement manipulation. This focus on micro-behavior does not capture the complexities of earnings management. Taking an institutional rather than agency theory approach, earnings management is posited as a decoupled behavior. A behavior that results from not only agency-based motivations of self-interests, but also regulative, normative, and cultural-cognitive legitimacy pressures. Conformity to the central logic of “maximizing shareholder value” found in the “US financial market” institutional field provides the context in which to explore earnings management as a decoupled behavior. Insights for earnings management include the blending of agency and institutional theory perspectives to gain a more complete understanding of the behavior and the positing of a continuum of earnings management conducive to this merger. Institutional theory benefits from exploring the nesting in multiple institutional fields.  相似文献   
30.
In the 1980s a number of large corporations restructured their diversified businesses through divestitures. It is hypothesized that restructuring activity focused on firms at intermediate levels of diversification (e.g., related-linked) which have a mixture of related and unrelated business units. Results confirm this hypothesis which explains that such mixed corporate strategies create organizational and control inefficiencies in managing both related and unrelated types of business units. Restructured firms were also found to move towards two types of different internal capital markets (related and unrelated). Most restructuring firms moved toward lower levels of diversification (e.g., related-constrained), although some moved toward higher levels of diversification (e.g., unrelated business). Also, this study finds restructuring firms that changed their corporate strategy by reducing diversified scope increased their R&D intensity. Firms that restructured and increased their diversified scope decreased R&D intensity. This result suggested a partial substitution between diversification and R&D activity.  相似文献   
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