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31.
法律的制定是一系列力量共同作用的结果,其中既有动力,也有压力和阻力。认真厘清和分析转基因生物安全立法的动力、压力和阻力,有利于推进转基因生物安全的立法进程、提高转基因生物安全法的立法质量。  相似文献   
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对珠江三角河网地带存在严重的路桥衔接处路面沉降差问题的原因进行了分析,指出目前设计规范存 在的不足,提出了解决该问题的建议,并介绍处理该问题的工程实践方法.  相似文献   
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This paper identifies which benchmarking databases are available for small- to medium-sized enterprises and the best way to conduct a benchmarking project given the limiting factors which exist at the present time. First, the meaning of benchmarking and performance measures, and their importance to an enterprise are explained. Second, frameworks for the identification of critical performance measures are considered. Third, different types of industrial benchmarking are identified and defined. Fourth, publicly accessible databases are critically reviewed against the requirements of industrial benchmarking. Fifth, the results of the critical review are presented in tabular form. Sixth, conclusions are drawn as how best to proceed with a benchmarking project at the present time. Seventh, recommendations for how best to address the issues raised by the critical review are presented.  相似文献   
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The relative performance of a component of a series system in two different environments is considered. The conditional probability of the failure of the system due to the failure of the specified component given that the system failed before time t is regarded as a measure of relative importance of the component to the system. A U-statistic test for checking the equality of the relative importance of the component to the system in two different environments against the alternative that the relative importance is smaller in one of the environments, is proposed. Some simulation results for estimating the power of the test are reported. The proposed test is applied to one real data set and it is seen that a different aspect of the data is brought out by this comparison than that by the comparisons of the absolute importance functions such as the subsurvival functions, considered in earlier studies.  相似文献   
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In this paper the Jackknife estimate of covariance of two Kaplan–Meier integrals with covariates is introduced. Its strong consistency is established under mild conditions. Several applications of the estimator are discussed.  相似文献   
39.
Multi-state models (MSMs) are useful to analyze survival data when, besides the event of main interest, one or more intermediate states of the individual are identified. These models take the several existing states and the possible transitions among them into account. At the same time, covariate effects on each transition intensity may be investigated separately and, therefore, MSMs are more flexible than the standard Cox proportional hazards model. In this work, we use MSMs to investigate the impact of the quality of a transplanted kidney for a group of patients at the Hospital Universitario Central de Asturias. Specifically, we use an illness-death model to study the evolution of patients with kidney disease who received a renal transplant after a dialysis period. The intermediate state is defined as the failure of the received organ, while the terminating state is the death of the patient. In order to increase the potential number of organs available for transplant, the standards of quality for the transplanted kidneys were relaxed (the new criteria are labeled expanded criteria), and these ‘expanded kidneys’ were transplanted in appropriate candidates (older patients, with higher prevalence of diabetes mellitus). Results suggest that the expanded kidneys have a minor effect on survival, while both the kidney mortality and the risk of death increase with the patient's age and the serum creatinine and serum hemoglobin levels.  相似文献   
40.
Unit level linear mixed models are often used in small area estimation (SAE), and the empirical best linear unbiased prediction (EBLUP) is widely used for the estimation of small area means under such models. However, EBLUP requires population level auxiliary data, atleast area specific aggregated values. Sometimes population level auxiliary data is either not available or not consistent with the survey data. We describe a SAE method that uses estimated population auxiliary information. Empirical results show that proposed method for SAE produces an efficient set of small area estimates.  相似文献   
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