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81.
Bengt Sundén Tor Sköldheden 《International Communications in Heat and Mass Transfer》1985,12(5):559-566
An experimental investigation of heat transfer and pressure drop from a new type of corrugated channels is presented. The investigation has been carried out for Reynolds numbers in the range of for one corrugated and one smooth channel. It is found that the heat transfer from the corrugated channel is up to 3.5 times higher than for the smooth one. The pressure drop is however large (5 – 6 times the value of a smooth channel) and it is suggested that the corrugation height and length should be altered in order to balance the increases in heat transfer and pressure drop. 相似文献
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This paper analyzes the welfare economics of three arrangements for purchasing health insurance: competitive markets in which consumers are free to choose among options with different levels of coverage and prices; systems with compulsory partial pooling which permit private firms to sell supplementary coverage; and government-run pools that purchase comprehensive coverage at a single price for all consumers. Competitive insurance markets are assumed to face the problem of 'adverse selection'. This refers to a situation in which the insurer cannot observe characteristics of individuals that affect the cost of insurance and that are known to the individuals. Competitive markets with adverse selection are not efficient because low risks cannot purchase comprehensive insurance coverage. However, government-run pools with comprehensive coverage are an inefficient solution to the problem of adverse selection. Compulsory partial coverage may represent an attractive alternative to both competitive markets and comprehensive pools. We discover two situations when government intervention of this type will succeed: when there are not many high risks in the population, and when the risk types are similar. We discuss the implications of these results for health insurance programs in several countries. Our results also have implications for the allocation of public funds for disease-prevention projects. A project targeted at high risks will produce external benefits for low risks, even though they are not directly affected by the program. However, a successful project might eliminate the market for private insurance; in this case the government should consider mandating partial insurance coverage. 相似文献
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Postoperative ventilatory depression is common in patients who have received intravenous and inhalational anesthetic agents. Prompt assessment and treatment of ventilatory depression are essential to minimize morbidity and mortality. 相似文献
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