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151.
基于政府视角的人力资本投资分析   总被引:4,自引:0,他引:4  
本文首先分析了政府在人力资本投资中的作用,然后从实现政府工作目标的角度探讨了人力资本投资的重要意义,最后提出增加人力资本投资的政策性建议.  相似文献   
152.
Institutions managing the Alaska road,rail, airport, and marine highwaytransportation system and the pipelinecorridor are evaluated for reactions toevidence of climate change. Long-termclimate warming is not a formal criterionin the decisional process of the stateDepartment of Transportation and PublicFacilities for road and airport projects,which have a short (15–25 year) life span,but is taken into account for bridgeconstruction (50–75 year life). Short- tomid-term climate effects are considered inareas with discontinuous permafrost andaffect routing, roadbed construction, andmaintenance decisions. National standardsare amended with Alaska-specific practicesfor unique cold-weather conditions.The Federal/State Joint Pipeline Office(JPO), responsible for monitoring ofpipeline safety under the federal lease andstate grant, in 2001 developed additionalstipulations to mitigate permafrost thawingand slope instability, including a `watchlist' of 200 wobbling VSMs on theTrans-Alaska Pipeline. This action appearsmore responsive to climate change effectsthan that of any other arctic institutionstudied. It can be attributed to thespecific authority of the JPO to monitorgeotechnical conditions at present and inthe future.In general, agencies tended to adoptincremental responses to evidence ofclimate change.  相似文献   
153.
再生资源产业发展中市场机制的缺陷和对策   总被引:1,自引:0,他引:1  
再生资源市场发展是再生资源产业发展的关键,但再生资源市场机制存在着一些缺陷,这些缺陷制约着再生资源市场的发展。政府应当针对再生资源市场的缺陷采取一定的对策,发挥杠杆作用,提高市场效率,但不应当支配市场主体的行为。政策的影响往往不会与政策设计的预期完全一致,在干预市场时依据一定的原则可以最大程度地减少不利影响,提高政策的积极作用。  相似文献   
154.
The 2011 Durban Adaptation Charter for Local Governments calls on local governments, worldwide, to institutionalise climate response, with the aim of minimising the impacts of climate change on local livelihoods and vulnerable communities. This paper, through the use of case studies, in-depth interviews and document review, assesses how three non-metropolitan municipalities in KwaZulu-Natal, a district municipality, and two local municipalities under its jurisdiction, are responding to this call. The results suggest that while the municipalities have adopted measures to institutionalise climate responses, the responses are relatively new and implementation is slow, complex and fraught with limitations and competing demands. Furthermore, there appears to be a lack of co-ordination of responses between the two levels of government, which has the potential to lead to duplication. Given the multi-scalar nature of climate change, emphasis on co-ordination and the inclusion of all municipal departments in the development and implementation of responses is necessary.  相似文献   
155.
经济发展方式的转变是我国化解资源环境约束、提高经济发展质量和效益、实现可持续发展的必由之路,而循环经济正是转变经济发展方式的有效途径。但实践中,有些地方政府和企业在用循环经济变革传统发展方式方面还存在种种误区,以致于严重偏离了循环经济的真正目标。通过对循环经济的目的、思路、实践、思想等内容的阐释,帮助人们准确把握循环经济要义,为积极推进经济发展方式转变提供参考。  相似文献   
156.
水葫芦用于水质污染治理的生态环境效应及其对策研究   总被引:4,自引:0,他引:4  
水葫芦净化水质的应用虽然已取得一定的成效,但是,由此却也伴生出一系列的问题。任何外来物种均是“双刃剑”,其带来的生态环境效应有利有弊。正确客观评估水葫芦这样的外来种的生态环境效应,对水葫芦生态工程净化工艺进行科学设计并逐步完善其净化系统,加强和优化生态工程的管理,从而使水葫芦达到对污染水体的最佳净化效果和对环境的最低危害程度,造福人类。  相似文献   
157.
我国畜禽养殖业存在的环境污染问题及治理对策   总被引:1,自引:0,他引:1  
畜禽养殖业环境污染问题越来越引起了人们的关注.本文概述了我国畜禽养殖业中存在的环境污染问题并从保护生态环境角度出发,提出了利用现代微生物工程应用技术和常规的处理方法相结合的治理措施。  相似文献   
158.
Brood guarding animals face many critical trade-offs. Sand goby males (Pomatoschistus minutus) build nests with larger openings during low oxygen conditions, presumably to enhance ventilation. However, this may make the nest easier for egg predators to detect and harder for guarding males to defend. Manipulating oxygen level and predator presence (a small crab) for small and large males, we found support for a parental trade-off between fanning and nest defense. An increased fanning activity resulted in less time for guarding. Small males and males in low oxygen showed a higher fanning expenditure than large males and males in high oxygen, but surprisingly, filial cannibalism did not differ between these groups. Males built larger nest openings in low than high oxygen. However, males in both high and low oxygen treatments reduced their nest opening size in the presence of a predator, again indicating an important trade-off between ventilation and nest defense.  相似文献   
159.
Sperm competition models predict that males should adjust their sperm expenditure according to the risk and/or intensity of sperm competition. In this paper, we analysed copulatory behaviour of both sexes and sperm expenditure in relation to female mating status (virgin or mated) in the freshwater crayfish Austropotamobius italicus, a species where males have been reported to feed on and remove sperm laid by other males. The same females were allowed to be inseminated sequentially by two males, and we compared the sexual behaviours of partners between the first (virgin females) and the second mating (mated females). We found that female resistance did not differ between the first and the second mating, nor males refused or took more time to mount a mated female. However, when mating with a mated female, males reached an effective copulation position significantly later. This occurred because second-mating males removed, by eating, all or most spermatophores previously deposited by first males. As removal was often incomplete, this resulted in a larger amount of sperm being deposited on female ventral parts after the second mating, although second males did not allocate more sperm to mated females than first males did. Thus, the peculiar mode of sperm competition, where males remove previously deposited sperm, and the consequent predictable strong last male prevalence in paternity likely led to the observed lack of adjustment of sperm expenditure to female mating status in this species.  相似文献   
160.
文章阐述了进行电熔镁生产含尘废气治理技术研究的必要性,通过对电熔镁生产污染治理技术措施进展情况分析,找出了技术比较先进、经济合理、处理效率较高的除尘设备,为电熔镁生产含尘废气的有效治理提供技术支持,为电熔镁企业选择合适的除尘设备提供参考.  相似文献   
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