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971.
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973.
Nontariff Barriers and Trade Liberalization   总被引:2,自引:0,他引:2  
This article shows that governments have no incentive to introduce nontariff barriers (NTBs) when they are free to set tariffs but they do when tariffs are determined cooperatively. Quotas are preferred to antidumping restrictions so that the model is consistent with a progression from using tariffs only to quotas and then to antidumping constraints (when quotas are eliminated). There is a corresponding narrowing of the range of industries affected by trade restrictions. Simulating the model, the degree of tariff liberalization and of replacement of tariffs by NTBs are shown to depend on industry characteristics in line with stylized facts.  相似文献   
974.
The use of average qualitative concordance between two bioassay endpoints is considered, with emphasis directed at agreement between rats and mice from results of long-term carcinogenicity studies. It is noted that concordance varies as a function of the underlying potency or toxicity of the chemicals over which the averaging is performed. Thus, the averaging process dilutes large observed concordances from potent chemicals, and possibly inflates lower observed concordances from weakly active chemicals. Stratification over some measure of potency is suggested as a method for taking these effects into account. Statistical simulations of concordance analyses limited to low-potency ranges are employed to examine the concordance measure in greater detail. It is seen that at low potencies, observed concordance is consistently underestimated, reaching maximum levels of only about 80%.  相似文献   
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Refinements of methods for life cycle impact assessment (LCIA) are directed at removing unjustified simplifications and quantifying and reducing uncertainties in results. The amount of uncertainty reduction that is actually achieved through LCIA method refinement depends on the structure of the life cycle inventory model. We investigate the general structure of inventory models using an economic input/output (I/O) life cycle assessment model of the U.S. economy. In particular, we study the results of applying a streamlining algorithm to the I/O LCA model. The streamlining algorithm retains only those "branches" of the process tree that are jointly required to account for a specified fraction of the total impacts upstream of each point in the tree. We examine the implications of these "tree pruning" results for site-informed LCIA. Percentiles are presented for U.S. commodities and several important pollutants, for the share of total upstream emissions contributed by the set of processes in each supply tier, that is, each set of processes that directly supply inputs to another set of processes Capturing at least 90% of the total direct plus upstream emissions for criteria air pollutants and toxic releases for at least 75% of the commodities in the U.S. economy requires full modeling of direct emissions plus the first five supply tiers. The requirements for capturing a high percentage (e.g., >80%) of total emissions vary widely across products or commodities. To capture more than 60% of total emissions for more than half of all commodities requires models with more than 4,000 process instances. To well characterize the total impacts of products, life cycle impact assessment methods must characterize foreground process impacts in a site-informed way and mean impacts of far-removed processes in an unbiased way.  相似文献   
977.
Popular strategies for reform have come directly from the private sector in what is perhaps the most profound redefinition of public administration since the field first emerged as an identifiable specialty. The purpose of this paper is to examine the context out of which these reforms have grown, the challenges that have arisen as a result, and cases where private sector reform strategies have been successfully (and sometimes unsuccessfully) applied in human resource management (HRM). We discuss the benefits and hazards of many of the reforms and conclude that restoring a measure of confidence in the legitimate role of the civil service is essential for nations dealing with the challenges of globalization.  相似文献   
978.
Emphasis on community-based treatment, along with the development of effective psychotropic medication, has resulted in a major shift in treatment methods for individuals with severe mental illness over the past several years. The primary strategies emphasized in current psychiatric rehabilitation efforts include the strengthening of (a) client skills and competencies and (b) environmental supports. The purpose of this article is to discuss successful psychiatric rehabilitation models and their impact on the social integration of people with severe mental illness.  相似文献   
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