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21.
生态美学--自然生态与文化生态的平衡   总被引:3,自引:0,他引:3  
生态美学包括自然生态与文化生态两大系统 ,而各自又有其分支系统 ,保持各系统的生态平衡以及两大系统之间的平衡对于审美与艺术的发生、价值构成有重大意义。在人与自然逐渐隔离的今天 ,生态美学的使命就是追求更深刻意义上的天人合一 ,人与自然的和谐 ,自然生态与文化生态的平衡与统一  相似文献   
22.
可持续发展理论的经济学反思   总被引:15,自引:2,他引:13  
由于可持续发展理论自身存在着一定的缺陷 ,使得这一理论在实践中实施效果不佳。在对可持续发展的概念、可持续发展与外部性的关系、生态成本等基本问题进行反思的基础上 ,提出在可持续发展的实施过程中要区分两类不同的问题。对于代内的现期环境问题可采取科斯手段与庇古手段来加强治理 ,而对于代际累积的生态问题则需要通过强化制度安排和政策引导来予以解决。  相似文献   
23.
21世纪西部大开发决不单纯是经济增长问题 ,它比经济增长应有更高的目标。人类社会在经历农业文明和工业文明之后 ,必然向生态文明社会发展。因此 ,西部大开发再不能走“先污染 ,后治理”的资源经济老路。以人为本是关键 ,建设生态经济是根本。  相似文献   
24.
高新技术企业价值与企业生命周期   总被引:1,自引:0,他引:1  
评估高新技术企业的价值要从其价值驱动因素入手,但高新技术企业在不同的生命周期阶段具有不同的价值驱动因素。因此,分析高新技术企业在生命周期各阶段的价值驱动因素以及相对应的价值评估方法,可以为高新技术企业的价值评估提供几点有益的启示。  相似文献   
25.
This paper examines local authority social workers' decision‐making when considering referrals of children, where the concerns are on the margin of child protection procedures. In doing so, it describes the findings of a qualitative research study undertaken in the policy context of attempts to ‘refocus’ social work practice in the late 1990s and early twenty‐first century. Data collection involved interviews with social workers and parents in 23 cases. Conclusions are that referrals were evaluated on the basis of five key factors, specificity, severity, risk, parental accountability and corroboration, the use of which determined whether an initial assessment or an investigation of alleged abuse took place. The analysis builds on previous work in the child protection field, but demonstrates how the application of these factors differs between cases of child concern and cases of child protection. Policy implications concern the complexity of decision‐making in the uncertain context of limited referral information and it is proposed that the simplistic notion of a continuum of abuse is now outdated. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
26.
Because of the inherent complexity of biological systems, there is often a choice between a number of apparently equally applicable physiologically based models to describe uptake and metabolism processes in toxicology or risk assessment. These models may fit the particular data sets of interest equally well, but may give quite different parameter estimates or predictions under different (extrapolated) conditions. Such competing models can be discriminated by a number of methods, including potential refutation by means of strategic experiments, and their ability to suitably incorporate all relevant physiological processes. For illustration, three currently used models for steady-state hepatic elimination--the venous equilibration model, the parallel tube model, and the distributed sinusoidal perfusion model--are reviewed and compared with particular reference to their application in the area of risk assessment. The ability of each of the models to describe and incorporate such physiological processes as protein binding, precursor-metabolite relations and hepatic zones of elimination, capillary recruitment, capillary heterogeneity, and intrahepatic shunting is discussed. Differences between the models in hepatic parameter estimation, extrapolation to different conditions, and interspecies scaling are discussed, and criteria for choosing one model over the others are presented. In this case, the distributed model provides the most general framework for describing physiological processes taking place in the liver, and has so far not been experimentally refuted, as have the other two models. These simpler models may, however, provide useful bounds on parameter estimates and on extrapolations and risk assessments.  相似文献   
27.
人才测评及其功能和发展   总被引:8,自引:0,他引:8       下载免费PDF全文
人才测评的发展是经济建设和社会发展的必然要求 ,为此本文讨论了人才测评的功能、特性以及今后的发展方向 ,明确了人才测评在整体性人力资源开发和管理中的重要意义  相似文献   
28.
A quantitative criterion for ranking the different scenarios of nuclear and radiological terrorism has been developed. The aim of the model is not to predict terroristic events but only to indicate which scenario has the higher utility from the point of view of a terroristic organization in terms of balance between factors favoring and discouraging the attack, respectively. All these factors were quantified according to a scoring system that takes into account the logarithmic relationship between perceptions and stimuli. The criterion was applied to several scenarios, each of which was modeled in a simple but not trivial way in order to estimate the expected damage in terms of probable life losses from both radiative and nonradiative effects. The outcome from the ranking method indicates that the attractive scenario appears to be the detonation of a low yield improvised nuclear device in the metropolitan area of a major city.  相似文献   
29.
PSC朗读评分中的语音缺陷问题   总被引:1,自引:0,他引:1  
在2002年12月《普通话水平测试大纲》修订工作征求意见稿中,我们发现它增加了对短文朗读中语音缺陷扣分的规定。短文朗读中的"语音缺陷"在《普通话水平测试大纲》现行评分标准中一直处于被忽视的地位。笔者同意征求意见稿的观点,对短文朗读中存在的"语音缺陷"应该扣分。短文朗读中存在的"语音缺陷"不能归入语音错误,也不能把它们划入"方言语调"的范围,应该把它们并入"方言色彩"的测试中。为此,笔者提出了短文朗读里语音缺陷的评分办法。  相似文献   
30.
The benchmark dose (BMD) is an exposure level that would induce a small risk increase (BMR level) above the background. The BMD approach to deriving a reference dose for risk assessment of noncancer effects is advantageous in that the estimate of BMD is not restricted to experimental doses and utilizes most available dose-response information. To quantify statistical uncertainty of a BMD estimate, we often calculate and report its lower confidence limit (i.e., BMDL), and may even consider it as a more conservative alternative to BMD itself. Computation of BMDL may involve normal confidence limits to BMD in conjunction with the delta method. Therefore, factors, such as small sample size and nonlinearity in model parameters, can affect the performance of the delta method BMDL, and alternative methods are useful. In this article, we propose a bootstrap method to estimate BMDL utilizing a scheme that consists of a resampling of residuals after model fitting and a one-step formula for parameter estimation. We illustrate the method with clustered binary data from developmental toxicity experiments. Our analysis shows that with moderately elevated dose-response data, the distribution of BMD estimator tends to be left-skewed and bootstrap BMDL s are smaller than the delta method BMDL s on average, hence quantifying risk more conservatively. Statistically, the bootstrap BMDL quantifies the uncertainty of the true BMD more honestly than the delta method BMDL as its coverage probability is closer to the nominal level than that of delta method BMDL. We find that BMD and BMDL estimates are generally insensitive to model choices provided that the models fit the data comparably well near the region of BMD. Our analysis also suggests that, in the presence of a significant and moderately strong dose-response relationship, the developmental toxicity experiments under the standard protocol support dose-response assessment at 5% BMR for BMD and 95% confidence level for BMDL.  相似文献   
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