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191.
简要介绍国外(美国)遥感测量技术在汽车排气检测领域的应用,并通过对广州市道路实车试验采集的数据进行机动车排放调查和IAVI项目评估,结果表明这些排放调查和评估工作是可行的,结果是可靠的。 相似文献
192.
This article discusses developments in the area of product service systems (PSS) and the need to facilitate the proliferation of the PSS approach through public policies. The article argues that policies that establish the framework conditions for environmental improvement are preferable to detailed legislation as they favour environmentally superior PSS. However, there is also a need for more specifically targeted policy measures that stimulate knowledge creation and dissemination in the PSS area. This article suggests that informative policy measures should be used by authorities and reviews the results from the functional programme of the Swedish EPA as an example of this type of policy. 相似文献
193.
ABSTRACT: The National Regulatory Research Institute has recommended the merger of small rural water districts in the United States. Success at bringing about merger of these districts, which contain fewer than 3,500 customers, has been highly limited. The subject of this paper is a demonstration project that may act as a catalyst to achieve the desired goal of regionalization. A computerized hydraulic data management program (CHDMP) was developed for a case study in Nelson County, Kentucky. University professors, graduate students, and two water utilities’ staffs cooperated in network analysis employing computer hardware and software. The utilities’ staffs were taught the science and technology of hydraulic model preparation, simulation, and analysis for the case study distribution systems. As an integrated system, the model contained 294 pipes, 234 nodes, six pumps, and 11 tanks. Each utility's problem areas were identified and some of the individual and mutual benefits of hydraulic planning were illustrated. A dialogue resulted between the managers. Each manager described his goals and agreed that, although political merger was not feasible at the present time, future economic factors could be a definite influence in reversing that decision. 相似文献
194.
甲型流感病毒H5N1的siRNA设计 总被引:1,自引:0,他引:1
选用了甲型流感病毒10个毒株(全序列)和一个2004年越南毒株(部分序列),采用自己编写的计算机程序sRNAFinder,对每个毒株的6个RNA片段的6个编码序列进行了siRNA设计.结合系统发育重建方法,利用sR-NAFinder的共有序列分析功能,对得到的6101个siRNA分子进行了计算机筛选.结果表明,设计的siRNA的分子,针对np和pb1应该是最有效的,而针对ha和na的siRNA分子设计,需要疾病流行期毒株的最新测序数据;从ns1的数据不能获得很保守的、可作为预防治疗药物的siRNA分子.图1表4参16 相似文献
195.
Markus Kirkilionis 《Environmental Modeling and Assessment》1997,2(4):297-306
The paper discusses the importance of understanding structural perturbations of models used in mathematical biology, where we mainly focus on ecology and dynamical systems. We describe first briefly the classical modeling strategy and the derivation of model structures. Structural perturbations are then discussed, mainly in the framework of ODEs. We give some examples how insights obtained from this type of model could be transfered to other kinds of models. Finally we propose an alternative modeling strategy characterized by a systematic investigation of a models neighbourhood in an appropriately chosen model class. 相似文献
196.
Qingyu Zhang Juwang Fan Weidong Yang Fang Ying Zhen Bao Yi Sheng Cheng Lin Xuan Chen 《环境科学学报(英文版)》2018,30(9):197-206
In this study, the influences of accumulated mileage(deterioration) and technological changes(emission standards) on emission factors(EFs) of regulated pollutants(CO, HC, and NO_x) from gasoline passenger vehicles were investigated based on Inspection and Maintenance(I/M) data using the chassis dynamometer method. The accumulated mileage of passenger vehicles was significantly linearly correlated with vehicle age. For most cases,the average EFs of CO, HC and NO_x were significantly linearly correlated with accumulated mileage, indicating that emission deterioration had a significant impact on pollutant EFs.Implemented emission standards markedly influenced the EFs of regulated pollutants, and EFs markedly decreased with progressing emission standards. The present study also compared EFs of regulated pollutants between this study and the International vehicle emission(IVE) model, and marked differences in EFs were seen with variations in emission standards, vehicle types and accumulated mileage; NO_x EFs in this study were higher than in the IVE model. The results provide new insight into estimating regulated pollutant emissions using the IVE model. 相似文献
197.
This paper is an effort to establish a lower bound on the economic value of the Columbia and Snake Rivers to the State of Washington, so as to assess the economic consequences of diversion of waters of these rivers to other geographic regions. The uses recognized in this paper are for power generation and irrigation, although the dynamic-programming model constructed is capable of incorporating, with minor changes, returns from other uses of the rivers when the economic data can be obtained. 相似文献
198.
本文系统分析和总结了美国在洪泛平原管理中的经验教训,研究了减灾措施、行为反应及国家长期减灾目标等方面的内容,从综合的角度提出了统一的国家减灾计划。 相似文献
199.
改建铁路沪汉蓉通道襄樊至安康段增建第二线铁路原设计增建第二线线路全长361.824km,其中Dzk67+480-D zk79+480段有12km经过武当山风景名胜区。为相应国家环境保护的号召,为了尽量减少工程建设对武当山风景名胜景区古建筑群的影响,工程在选线过程中绕避古建筑群,以隧道隐蔽工程穿过,且对原生态环境影响最小。 相似文献
200.
环境污染源信息管理系统的开发 总被引:2,自引:1,他引:1
污染源数据是重要的基础环境数据。为了配合全国污染源普查,全面掌握环境污染现状,提高对污染源数据的管理效率,利用Visual Basic和Microsoft Acess数据库相结合的技术,开发了环境污染源信息管理系统。进行了管理系统和数据库的总体设计、结构构建和操作界面设计。根据用户需求,利用Vb控件和SQL语句设计了六大功能模块,实现了对污染数据进行编辑、浏览、查询、统计分析和打印输出等功能。为企业制定节能减排的环保决策提供有力的技术支持。 相似文献