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731.
732.
国外光伏发电并入智能电网发展探讨 总被引:1,自引:0,他引:1
智能电网是未来电网发展的主要趋势。随着人们对环境保护的重视,如何将风能、太阳能等可再生能源大规模接入电网已经成为智能电网下一阶段的研究方向。介绍了国外光伏发电技术发展,概述了国外对光伏发电并入智能电网的最新研究,提出了光伏并网发电面临的问题以及相关建议,为我国未来光伏并网发电的实施提供参考。 相似文献
733.
A. G. Venetsanos D. Vlachogiannis A. Papadopoulos J. G. Bartzis S. Andronopoulos 《Water, Air, & Soil Pollution: Focus》2002,2(5-6):325-337
Remote sensing instruments may be used to make measurements of emission levels from individual vehicles under realdriving conditions. In designing such an instrument, that will identify the gross polluters, the CFD modelling approach has been used to study the effects of the parameters involved on the characteristics of the exhaust gas plume. The analysis was performed using the ADREA-HF code in open space, street canyon and tunnel environments, with sensitivity parameters the car speed and meteorological conditions. The calculations have been performed in a moving coordinate system, with the car and site geometry being fully resolved. A discussion is given on the effects of the various parameters affecting the design of the instrument. 相似文献
734.
The concept of a recycling system aiming at the recovery of resources from manufactured articles is proposed. The system integrates electronic labels for product identification and internet for global data exchange. A prototype for the recycling of electric motors has been developed, which implements a condition-based recycling decision system to automatically select the environmentally and economically appropriate recycling strategy, thereby opening a potential market for second-hand motors and creating a profitable recycling process itself. The project has been designed to evaluate the feasibility of electronic identification applied on a large number of motors and to validate the system in real field conditions. 相似文献
735.
Abdul-Wahab SA 《Environmental management》2004,34(3):372-382
The CAL3QHC model was used to predict carbon monoxide (CO) concentrations from motor vehicles at an existing urban intersection (Star Cinema in Muscat area, Oman). The CO concentrations predicted from the model were compared with those measured in the field. Predicted average CO concentrations were found to compare favorably with measured values obtained at all eight receptors considered within the modeled intersection. In general, the comparison indicates good agreement with some underprediction for CO. For receptor 6, the model overpredicts the average CO concentration. This overprediction is associated with the presence of trees and green area in the location of receptor 6. In general, the measurements and the model results indicated that the highest CO concentrations were found to occur close to the intersection and, hence, a decrease in the concentration levels was seen as the distance from the road increased. The results indicated that the levels of CO were well below the ambient air quality standard and that probably no health risk was present in areas adjacent to the star cinema intersection. However, the predicted worst-case 1-h CO concentrations assuming inversion atmospheric stability conditions (class F) and wind speed of 1 m/s indicated that the levels of CO were close to or higher than the Omans National Ambient Air Quality Standards (NAAQS) value of 35 ppm at all receptors considered. The results of this study are useful in transport development and traffic management planning.Published online. 相似文献
736.
电场、磁场和电磁场的环境问题 总被引:2,自引:1,他引:2
针对近年来越来越突出的输变电工程电磁环境纠纷等问题,从电磁场理论的角度,对电场、磁场和电磁场的传播及特性进行分析,以求正确地分析与解释电磁场辐射问题,减少误解和随之产生的不必要纠纷. 相似文献
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739.
The 2006 end-of-life vehicles (ELVs) directive target for the recycled and reused material content of an ELV has been undertaken using the current recovery infrastructure within the UK. The current expectation is that the conformance for the 2006 recycling target will be mainly achieved using existing post-fragmentation separation technologies rather than manually disassembling vehicles into their constituent materials. With the economic pressure of the current legislative targets weighing heavily on end-of-life stakeholders, and the further increase of recycling levels for 2015, it is important to understand “when” and “if” manual dismantling activities become economically viable within a dramatically changing vehicle recovery industry. This paper describes a method of costing the dismantling of specific makes and models of vehicle due for retirement in 2015, and discusses the economic implications of such practice and possible strategic directions for pre-fragmentation vehicle recovery. 相似文献
740.
Steve H. Hanke John J. Boland 《Journal of the American Water Resources Association》1972,8(3):446-458
ABSTRACT The generation of electric energy in steam-electric power plants is accompanied by the discharge of large quantities of waste heat into the environment. In most cases, this heat is released into natural bodies of water at temperatures relatively close to ambient. In certain locations, such as the Chesapeake Bay, discharges of waste heat may triple in the next decade. It is expected that past practices of thermal discharge, if continued into the future, will result in significant damages to other legitimate users of the water resource, both present and future. This paper reviews the economic causes of these potential damages, and describes the role of public policy as one of removing such causes through regulation incentive or intervention. Possible public policies are reviewed, including prohibition, standards, various types of dollar incentives such as taxes and subsidies, marketable effluent permits, and direct government investment. The innovative power plant siting program recently adopted in Maryland is also discussed. It is concluded that no statements can be made regarding the comparative efficiency or effectiveness of the various policies at the present state of knowledge. It is recommended that policy-makers adopt mixed strategies, preserving as many options as possible for dealing with similar problems in the future. 相似文献