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101.
Federal, state, and local governments use a variety of incentives to induce consumer adoption of hybrid-electric vehicles. We study the relative efficacy of state sales tax waivers, income tax credits, and non-tax incentives and find that the type of tax incentive offered is as important as the generosity of the incentive. Conditional on value, sales tax waivers are associated with more than a ten-fold increase in hybrid sales relative to income tax credits. In addition, we examine how adoption varies with fuel prices. Rising gasoline prices are associated with greater hybrid vehicle sales, but this effect operates almost entirely through high fuel-economy vehicles. By comparing consumer response to sales tax waivers and estimated future fuel savings, we estimate an implicit discount rate of 14.6% on future fuel savings.  相似文献   
102.
Focusing specifically on regulation of coal-fired power plants, we examine how technological innovation by early adopters influences the timing of new environmental regulation in non-innovating countries. We build a general equilibrium model of an open economy to identify the political-economy determinants of regulation. With a newly created dataset of SO2 and NOx regulations for coal-fired power plants and a patent-based measure of the technology frontier, we estimate the determinants of environmental regulation diffusion. Our findings support the hypothesis that international economic integration eases access to environmentally friendly technologies and leads to earlier adoption, ceteris paribus, of regulation in non-innovating countries. However, we also find evidence that domestic trade protection promotes earlier adoption allowing shifts of regulatory costs to domestic consumers. Furthermore, international market power permits large countries to shift costs to foreign consumers. Other political economy factors, such as the quality of domestic coal, are also important determinants.  相似文献   
103.
遥感技术在湖泊水质监测中的应用   总被引:1,自引:0,他引:1  
环境污染遥感监测技术具有监测范围广、速度快、成本低,且便于进行长期的动态监测等优点,是实现宏观、快速、连续、动态地监测环境污染的有效方法,已成为湖泊环境动态变化监测的重要技术手段.湖泊水质遥感监测是基于经验、统计分析或水质参数的光谱特征,选择遥感波段数据与地面实测水质参数数据进行数学分析,建立水质参数反演模型实现的.在运用遥感技术对湖泊进行水质监测的方法中有传统方法和神经网络模型.与传统方法相比,神经网络模型有较强的水质识别的容错性,水质状况识别的可信度.今后,神经网络模型、高光谱遥感技术以及RS与GIS、GPS的结合运用等将是遥感技术在此领域中的发展方向.  相似文献   
104.
地震烈度包络线的遥感与GIS方法快速生成   总被引:7,自引:1,他引:7  
地震烈度包络线通常用地面调查宏观地震影响和破坏现象来划分。本文介绍在完成国家“八五”科技攻关项目中,突破常规调查方法,采用遥感与GIS技术,在室内针对震害遥感影像完成震害分类分级,进而通过人机对话完成地震烈度包络线的快速生成的方法和技术。运用该技术以唐山地震区作模拟试验表明:遥感与GIS技术快速生成的高烈度包络线,不仅使大量实地调查变为室内遥感应用分析,时效提高了10倍,而且其轮廓形状更趋客观实际。  相似文献   
105.
Measurements of primary productivity and its heterogeneity based on satellite images can provide useful estimates of species richness and distribution patterns. However, species richness at a given site may depend not only on local habitat quality and productivity but also on the characteristics of the surrounding landscape. In this study we investigated whether the predictions of species richness of plant families in northern boreal landscape in Finland can be improved by incorporating greenness information from the surrounding landscape, as derived from remotely sensed data (mean, maximum, standard deviation and range values of NDVI derived from Landsat ETM), into local greenness models. Using plant species richness data of 28 plant families from 440 grid cells of 25 ha in size, generalized additive models (GAMs) were fitted into three different sets of explanatory variables: (1) local greenness only, (2) landscape greenness only, and (3) combined local and landscape greenness. The derived richness–greenness relationships were mainly unimodal or positively increasing but varied between different plant families, and depended also on whether greenness was measured as mean or maximum greenness. Incorporation of landscape level greenness variables improved significantly both the explanatory power and cross-validation statistics of the models including only local greenness variables. Landscape greenness information derived from remote sensing data integrated with local information has thus the potentiality to improve predictive assessments of species richness over extensive and inaccessible areas, especially in high-latitude landscapes. Overall, the significant relationship between plants and surrounding landscape quality detected here suggests that landscape factors should be considered in preserving species richness of boreal environments, as well as in conservation planning for biodiversity in other environments.  相似文献   
106.
Barry Kirwan   《Safety Science》2001,37(2-3):77-107
In 1997 a workshop was held on the subject of how to cope with accelerating technologies. These are industries such as aviation, air traffic control and biotechnology, amongst others, where the rate of technological development is significant. A number of papers were presented from a range of viewpoints and in a variety of different industrial contexts. The papers ranged from theoretical models to help understand the process of acceleration and its impact on organisational learning, to practical analyses of future potential risks in specific accelerating industries such as air traffic control. The aim of the papers and the workshop as a whole was to provide insight into the problems associated with accelerating technologies, and thereby derive measures to control or cope with such acceleration. The problems arising from acceleration, as predicted by the theoretical models and evidenced by experiences in accelerating industries (e.g. aviation) are manifold. Two examples of particular problems are unforeseen risks in an industry (a lack of forward vision), and a failure to learn adequately (i.e. in time) from incidents occurring in an organisation (a lack of constructive hindsight). There is also an incipient danger of society being driven by technology rather than being led by social needs. Even if each technology ultimately becomes ‘ultra-safe’, it will nevertheless have its own ‘event horizon’, limiting useful further progress. Each of the papers from the workshop is summarised and integrated into a three-part synopsis of the workshop. This covers the context of accelerating technologies, modelling their impacts, and deriving coping strategies. Four of the papers are included in their entirety as separate papers in their own right in this special issue of Safety Science.  相似文献   
107.
青藏铁路景观视觉管理系统研究   总被引:8,自引:0,他引:8  
铁路建设需要设置取(弃)土场、砂石料点、施工营地等工程场地,这些工程场地如果设计不合理,必将对沿线景观造成破坏,进而对视觉产生强烈的冲击。该文参考美国林务局的“视觉管理系统(VisualManagementSystem,VMS)”和美国土地管理局的“视觉管理(VisualResourcesMana-gement,VRM)”,利用遥感(RS)和地理信息系统(GIS)技术,结合新建青藏铁路沿线景观特点和工程场地的位置、面积、所处的坡度、相对于铁路的距离、沿铁路方向的长度以及相对于本底景观的对比度,建立了新建青藏铁路沿线的景观视觉管理系统,定量分析和评价了铁路建设工程可能对高原景观带来的冲击,并为修改和重新设计工程场地提出了指导性建议。  相似文献   
108.
An optimized code for the near real-time retrieval of line of sight, temperature and volume-mixing ratio profiles of five key species (O3, H2O, HNO3, CH4 and N2O) from infrared limb spectra recorded by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS) experiment on board the ENVISAT-1 satellite was developed as part of an ESA-supported study. In this code line of sight and temperature are retrieved simultaneously among themselves, but sequentially with respect to the volume-mixing ratio of the five key species. The sequential retrieval leaves unaccounted the mapping of line of sight and temperature errors in the retrieved volume-mixing ratio of the constituents. This paper illustrates an algorithm that provides the a-posteriori evaluation of temperature and line-of-sight-induced error on the retrieved volume-mixing ratio of the MIPAS key species. It is shown that in most cases temperature and line-of-sight-induced error provides a significant contribution to the total volume-mixing ratio error. The variability of this error as a function of latitude, season and atmospheric model is also analyzed.  相似文献   
109.
Observations of air pollutants were conducted in remote Japanese islands (Oki Island and Okinawa Island) in early spring to clarify the extent of trans-boundary air pollution from the Asian continent. A three-dimensional Eulerian model calculation, which included parameters on emission, transport and transformation of sulfur oxides, nitrogen oxides and ammonia, was performed to compile sulfate isosurface concentrations over the observational sites. Concentrations of non-sea-salt sulfate (nss-SO42−) of greater than 10 μg m−3 were observed at Oki after the northeastward passage of low-pressure systems in the Sea of Japan. At these times, the weather showed a typical winter pattern and air pollutants over China were transported southeastward to Japan with the northwesterly wind. The model calculation reproduced the observed variations of nss-SO42− concentration well, except for one case in which the model calculation could not reproduce the extremely low nss-SO42− concentration observed on 8 March. In Hedo (Okinawa Island), we observed long-lasting (3 days) medium concentrations of nss-SO42− (approximately 5 μg m−3). Although the model reproduced these observed medium concentrations well, in general the observed results were reproduced better for Oki than for Hedo. Under the synoptic weather conditions of early spring, high concentrations of nss-sulfate were sometimes transported to these remote Japanese islands from areas of continental Asia with a strong outflow of air pollutants.  相似文献   
110.
医院安全保障体系的技术构成包括安全的诊疗救护技术、后勤供养技术和安全保卫技术。其技术特点是以人为本 ,服务健康 ,应急性强 ,发展迅速 ,互相影响。本文提出了医院安全保障体系改革的构想和建立医院安全保障体系中应考虑的技术因素。  相似文献   
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