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811.
The maritime industry provides an interesting case study of the design and implementation of drug-testing programs in the transportation industry during the 1980s. It is clear that such programs were designed and implemented less because of empirical evidence of safety problems than for political reasons. The results in the maritime industry are indicative of a program that is expensive to operate, intrusive with regard to employee privacy, and which will have little or no impact on safety. Focusing such programs on the issue of impairment rather than on the issue of drug usage per se is likely to improve the outcome of the programs. Although, despite common belief, there is little evidence that drug usage or the “drug problem” in U.S. society as a whole had gotten worse in the preceding years (Schonsheck, 1989, 250–251).  相似文献   
812.
Too often companies fall into a trap when developing a list of performance specifications for a new product. Milton Rosenau calls this the best-of-the-best specification trap. The problem arises whenever a company bases a specification on the combination of the best single features observed in available competitive products. When this happens, the new product's design is driven by competition and is not derived from a unique market insight. This may not provide the basis for a sustainable advantage. Sometimes, rumors of competitive improvements may even lead to sudden changes in the specification, creating delays in the development process. A far better goal is to develop a specification that responds to an unrecognized and unfilled user need, one that adds high value to users. His points are illustrated with several examples.  相似文献   
813.
814.
Agricultural trade impasses have again frustrated the GATT process. Interest in preferential/regional trading blocs is increasing. the paper probes the theoretical and empirical consequences of preferential arrangements instead of multilateral liberalization. It concludes that in a second-best world preferential arrangements could either improve or decrease global welfare. For agricultural trade, previous experience suggests that in regional groupings such as the EC trade diversion exceeded trade creation. This results from trade distorting domestic policies. Prospects for liberalization of agricultural trade under either GATT or preferential arrangements are limited. the consequences for small agricultural exporters are not positive.  相似文献   
815.
This paper concerns the behavior of gold and silver prices on a daily, weekly and monthly time span during January 1970 to December 1989. The methodology consists of extracting the predictive power of time series of changes in past prices for obtaining optimal forecasts for next-period changes in prices. Optimizations are made in the context of information theory via minimizing the degree of diversity between the actual and predicted changes in prices. This methodology has merit in that it does not rest on, generally speaking, unacceptable assumptions regarding the shape of the distribution, stationarity of variance or its existence. The behavior of gold and silver prices are studied during peak to trough and trough to peak of the business cycles over 1970–1989. It is generally shown that information contained in past prices of gold and silver does not allow one to predict next-period changes in prices in the short run. However, longer-term predictions are possible. This study further reveals that as the length of the time interval expands, gold prices exhibit a higher degree of dependency on past prices than silver.  相似文献   
816.
817.
The recent revival of interest in the issue of limiting auditors' liability raises questions about the potential effect of such a limitation on auditors' performance. This paper considers the consequences of limited liability from the perspectives of contracting theory and economic arguments. We examine the potential effect of a reduction in auditors' liability on the standard of care or quality of service they provide, emphasising the "calculus of negligence" concept used by Australian courts. We consider the potential impact of reduced liability on the auditor's decision to shirk responsibilities (the moral hazard problem) and on the value placed on audit services. The analysis shows that placing a statutory cap on auditors' liability has the potential to reduce the effectiveness of bonding mechanisms; provide an avenue for divergent behaviour; lower the level of care provided by auditors; and decrease the value of audit services.  相似文献   
818.
819.
820.
The effects of exogenous water and salts on lipid oxidation in ground beef were determined. Deionized water, salts, or both, were added to treatment samples. Salts used were sodium chloride, potassium chloride and sodium sulphate, all at 3% concentration. The Thiobarbituric acid (TBA) test was used to assess lipid oxidation. Addition of water at a 10% or 20% level had no effect on rancidity. Sodium chloride and potassium chloride reduced TBA numbers. Adding water to those samples containing potassium chloride and sodium sulphate raised moisture content.  相似文献   
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