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71.
ABSTRACT

The drive range of electric vehicle (EV) is one of the major limitations that impedes its universalism. A great deal of research has been devoted to drive range improvement of EV, an accurate and efficiency energy consumption estimation plays a crucial role in these researches. However, the majority of EV’s energy consumption estimation models are based on single motor EV, these models are not suitable for dual-motor EVs, which are composed of more complex transmission mechanisms and multiple operating modes. Thus, an energy consumption estimation model for dual-motor EV is proposed to estimate battery power. This article focuses on studying the operating modes and system efficiency in each operating mode. The limitation of working area of each mode ensures the vehicle dynamic performance, then PSO algorithm is adopted to optimize the torque (speed) distribution between two motors to improve the system efficiency in the coupled driving mode. Finally, the energy consumption estimation model is established by multiple linear regression (MLR). The result shows that the proposed model has a high precision in energy consumption estimation of dual-motor EV.  相似文献   
72.
In this article, the systems for the collection and intermediate processing of used beverage cans (UBCs) are compared and analyzed, focusing on the time taken and the cost of processing, the energy consumption, and the emissions of CO2, SO x , and NO x , during the process. We found that cases where the UBCs were crushed in the discharging process gave better results, and how the UBCs were collected was the most important factor. It was more desirable to treat UBCs in one place than in two places. When the transportation distance was longer, the pressed form of UBCs was more convenient. When the transportation distance was short, the original form, the crushed form, and the shredded form of UBCs were all suitable. That is, the contribution of the transportation process to the evaluation was large when the transport distance was long, and the contribution of the treatment process was large when the transport distance was short.  相似文献   
73.
In order to improve the process performance regarding the removal of organics, nitrogen, and an odor-causing compound (sulfide) contained in domestic wastewater, an entrapped-mixed-microbial cell (EMMC) with and without humic substances for both fixed and moving carrier reactors and conventional suspended growth culture (i.e. conventional activated sludge process) were investigated simultaneously. Both synthetic (simulated to the organics concentration of general domestic sewage) and actual domestic wastewater were investigated under operational conditions of 12 h of hydraulic retention time (HRT) with 1 h of aeration and 1 h of non-aeration, and 6 h of HRT with continuous aeration, at a room temperature of 25 +/- 2 degrees C. It was found that entrapping humic substances in the EMMC carriers had no impact on the removal of organics, nitrogen, and the odor-producing compound. Additionally, the performance of the EMMC moving carrier system for the removal of these pollutants is similar to that of the EMMC fixed carrier system. In general, the EMMC associated systems which provide high solids retention time achieve a better removal of chemical oxygen demand (COD), nitrogen, and the odor-producing substance than the suspended growth system for both HRTs of 6 h (continuous aeration) and 12 h (1 h of aeration and 1 h of non-aeration). Both the fixed and moving carrier EMMC processes, therefore, have the potential for improvement or replacement of the existing conventional activated sludge process with regard to improving the effluent qualities (such as COD, nitrogen and odor-producing compound) for reuse/disposal.  相似文献   
74.
组合优化的能源消费量预测模型   总被引:1,自引:0,他引:1  
田峻山  俞奇勇  张帆 《资源开发与市场》2007,23(10):893-895,954
针对非等间距灰色系统预测中存在误差较大的问题,结合序列本身的特点,利用世界能源消费的历史数据,采用3种灰色预测模型与神经网络进行组合优化,建立了灰色神经网络的能源消费量组合预测模型。实证分析结果表明,提高了模型的拟合和预测精度,拓宽了应用范围。该模型可对能源的消费趋势进行预测,为科学分析能源结构提供依据。  相似文献   
75.
The purpose of this study is to shed light on the connection between income, dwelling type, tenure type and city living, in terms of both a household’s energy saving behaviours and direct residential energy consumption. This study employs data from the Household Energy Consumption Survey, Australia. Using a seemingly unrelated regression (SUR) system of equations the results reveal some key mechanisms which may allow householders to realise lower levels of energy consumption and hence lower carbon emissions. The results indicate that there are characteristics unique to living in a city that are linked to higher levels of direct residential energy consumption. On a number of measures (e.g. household income, tenure type and dwelling type), the results point to a lower likelihood of engaging in energy saving behaviours in cities. Also, depending on the number of energy saving behaviours, these actions have the potential to more than offset higher direct residential energy consumption of householders residing in separate houses. Coupled with these findings renters, a more vulnerable social group, are found to be significantly disadvantaged, suffering from a much lower adaptive capacity. Specifically, householders who rent their home are 77% less likely to have solar electricity. A result which may reflect differences in access to opportunity. Further, householders who rent are less likely to engage in energy saving actions. A finding which may reflect difference in ontological security and the greater psychological burden associated with undertaking energy saving behaviours (a barrier) borne by renters not shared with home owners.  相似文献   
76.
武钢三烧区域改建了二台大连三洋蒸汽型双效溴化锂吸收式制冷机。叙述了该改建项目的主机选型、参数选定、设计特点等。  相似文献   
77.
This paper aims to identify the main driving force for changes of total primary energy consumption in Beijing during the period of 1981-2005. Sectoral energy use was investigated when regional economic structure changed significantly. The changes of total primary energy consumption in Beijing are decomposed into production effects, structural effects and intensity effects using the additive version of the logarithmic mean Divisia index (LMDI) method. Aggregate decomposition analysis showed that the major contributor of total effect was made by the production effect followed by the intensity effect, and the structural effect was relatively insignificant. The total and production effects were all positive. In contrast, the structural effect and intensity effect were all negative. Sectoral decomposition investigation indicated that the most effective way to slow down the growth rate of total primary energy consumption (TPEC) was to reduce the production of the energy-intensive industrial sectors and improving industrial energy intensity. The results show that in this period, Beijing's economy has undergone a transformation from an industrial to a service economy. However, the structures of sectoral energy use have not been changed yet, and energy demand should be increasing until the energy-intensive industrial production to be reduced and energy intensity of the region reaches a peak. As sequence energy consumption data of sub-sectors are not available, only the fundamental three sectors are considered: agriculture, industry and service. However, further decomposition into secondary and tertiary sectors is definitely needed for detailed investigations.  相似文献   
78.
This article analyzes China's coal consumption changes since 1991 and proportion change of coal consumption to total energy consumption. It is argued that power, iron and steel, construction material, and chemical industries are the four major coal consumption industries, which account for 85% of total coal consumption in 2005. Considering energy consumption composition characteristics of these four industries, major coal demand determinants, potentials of future energy efficiency improvement, and structural changes, etc., this article makes a forecast of 2010s and 2020s domestic coal demand in these four industries. In addition, considering such relevant factors as our country's future economic growth rate and energy saving target, it forecasts future energy demands, using per unit GDP energy consumption method and energy elasticity coefficient method as well. Then it uses other institution's results about future primary energy demand, excluding primary coal demand, for reference, and forecasts coal demands in 2010 and 2020 indirectly. After results comparison between these two methods, it is believed that coal demands in 2010 might be 2620-2850 million tons and in 2020 might be 3090-3490 million tons, in which, coal used in power generation is still the driven force of coal demand growth.  相似文献   
79.
为了更有效地执行我国能效等级评价标准和降低办公能耗,着重讨论了打印设备的能源效率评价。通过收集的数据来分析打印机能效限定值及相应的能效等级标准的测试方法测试过程中的关键点。通过引入计算模型和介绍测量典型能耗分析法(TEC),操作模式功率法(OM)的步骤和检测方法。对检测需要注意的项目以及有效降低电力能源消耗提出对应的方案和建议。  相似文献   
80.
智能电能表功耗测量是一项重要的试验项目,介绍了电能表功耗测量仪和连接,着重分析了功耗测量系统软件的设计。该软件用于功耗测量数据采集,分析了其中的关键技术,给出了Lab VIEW设计框图。该软件实现了智能电能表功耗数据的自动化测量。  相似文献   
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