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1.
Although China committed to reduce its energy and emission intensity, the allocation of such national targets in the provincial level is still a political negotiation process and lack of a systematic principle from the perspective of efficiency. This paper proposes an allocation principle based on the efficiency levels. The efficiency levels are estimated by employing a stochastic frontier analysis approach and the links between energy intensity and efficiency are constructed. The results show that energy efficiency change is not the major contributor to energy intensity reduction. Furthermore, this analysis indicates that (i) the efficiency-based allocation can distribute reduction burdens among regions smoothly compared to the intensity-based allocation; and (ii) the national target of emission intensity reduction can be achieved solely through efficiency measures.  相似文献   
2.
In recent years,the damage of Apocheima Cinerarius Erschoff in Xinjiang province has seriously threatened the survival and green barrier function of natural Populus euphratica.Due to the large coverage and high tree body of Populus euphratica,traditional monitoring methods are difficult to meet the requirement of rapid monitoring of pest.In this study,the NDVI time series data set of Xiamale forestry in Xinjiang Bachu was reconstructed from the MODIS data from 2014 to the first half of 2017,and the NDVI time series curves were further fitted by three filters.It is found that the S\|G filter can preserve more details of the original curve,and the global fitting can weaken the heterogeneity effectively,so that the vegetation coverage space is better.Through the analysis of the NDVI time series data of the aircraft control area and the comparison with catastrophe point of the non\|flight zone,it is found that the aircraft biological agent means has obvious and continual effects on the controlling of insect pests.proven by the investigation of pest’s population on the ground..The results showed that it was feasible to analyse the insect pests by using the time series of Populus euphratica NDVI.  相似文献   
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张波  杨勇  夏泽宇 《硅酸盐通报》2021,40(7):2200-2208
通过32个加固柱及4个对比柱试件的轴压性能试验,研究了钢带间距、层数对承载力及变形能力的影响。试验结果表明,混凝土圆柱试件经预应力钢带加固后,不仅可以提高柱的轴压承载力,还能使加固柱具有良好的变形能力,可有效改善其轴压性能。在试验研究的基础上,分析了预应力钢带加固混凝土柱轴压受力机理,提出了预应力钢带加固混凝土圆柱极限强度模型,计算值与试验值吻合程度较好。  相似文献   
5.
为了实现更高精度的大坝变形预报,提出了一种大坝变形的XGBoost-LSTM变权组合预测模型,即首先引入XGBoost模型和LSTM模型对大坝变形分别进行分析预测,然后采用变权组合方法将二者的分析预测结果进行有机融合,进而得到最终预测结果。以某混凝土重力坝为例,首先通过与随机森林、ELMAN以及逐步回归分析各模型的对比研究,论证了XGBoost与LSTM应用于大坝变形预测的优越性;进一步地,XGBoost与LSTM的变权组合预测效果相较于各单一模型取得了较大程度的提升,且相较于二者的等值赋权组合提升优势更加显著,变形预测结果与工程实际情况更加吻合,具有较好的适用性和可推广价值。  相似文献   
6.
国外抽水蓄能电站的运营模式和电价机制   总被引:3,自引:0,他引:3  
介绍和分析国外抽水蓄能电站的运营模式和电价机制,着重分析了日本、英国、美国的情况,指出日本是弱化电量竞争、强化容量效益的租赁制;英国的抽水蓄能电价机制相当于一种两部制;美国的机制随各州电力市场模式的不同而有所不同,但总体上仍体现容量和电量这2部分收益。结合我国节约能源、保护环境的形势,得出了适度发展抽水蓄能电站是必要的、迫切需要制定符合国情的抽水蓄能电价机制和确定抽水蓄能电站经济效益的量化评价标准是抽水蓄能电价机制的核心问题的结论。  相似文献   
7.
区域良性水循环的探讨和示范   总被引:3,自引:0,他引:3  
区域良性水循环的核心内容是节水、雨水利用和中水回用(包括污水处理)的集成应用,开源节流相结合,通过水的循环利用,提高用水效率,争取达到零排放的目标。本文在区域良性水循环理论研究的基础上,选择北京市怀柔应急水源地进行示范,完成了节水、办公楼及路面的雨水收集和利用系统,中水处理及回用系统,绿地灌溉系统的集成应用,提出了小区域水资源高效利用、零排放的良性循环模式。在示范区内,下雨时路面不产生积水,生活污水被全部处理和应用,绿地灌溉均采用处理后的水,植物长势良好,充分体现了水在小区域的良性循环,该模式对整个北京市的大区域良性水循环的建立具有一定的借鉴和示范作用。  相似文献   
8.
能源是人类社会文明演进的前提和基础,能源发展是生态文明建设的重要组成部分,能源生产利用方式的变革创新是经济社会转型升级的关键。本文阐述了生态文明与能源变革的社会作用,分析了我国能源发展与发达国家之间的差距及存在问题,并根据未来国际能源发展总体趋势,阐述了我国能源发展面临的挑战和机遇。结合能源需求预测分析,指出我国能源变革的必要性,为我国生态文明建设与能源发展和变革提供战略决策及参考依据。  相似文献   
9.
《Energy Policy》2005,33(3):279-287
Eastern Coastal areas of China have been developing rapidly since the implementation of reforms and the opening of China's economic markets in 1978. As in most areas of the world, this rapid economic growth has been accompanied by large increases in energy consumption. China's coal-dominated energy structure has resulted in serious ecological and environmental problems. Exploiting renewable energy resources and introducing Renewables Portfolio Standard (RPS) are some of the most important approaches towards optimising and sustaining the energy structure of China. This paper discusses international experiences in the implementation of RPS policies and prospects for using these policies to encourage renewable energy development in China, establishes a concise definition of renewable resources, differentiating between the broad definition (which includes hydro over 25 MW in size) from the narrow definition (which limits the eligibility of hydro to below 25 MW in size), and quantitatively analyses the potential renewable energy target. The research shows that: (1) Under the narrow hydro definition the renewable energy target would be 5.1% and under the broad hydro definition it would be 18.4%. (2) Western China has contributed 90.2% of the total renewable electricity generation in the country (if big and medium hydropowers are not included). Including big and medium hydropower, the figure is 63.8%. (3) Eastern electricity companies can achieve their quota by buying Tradable Renewable Energy Certificates (TRCs or Green Certificates) and by exploiting renewable energy resources in Western China. The successful implementation of the RPS policy will achieve the goal of sharing the benefits and responsibilities of energy production between the different regions of China.  相似文献   
10.
阐述了巴西、阿根廷、古巴节能产品质量监管的基本情况,系统分析对比了巴西、阿根廷、古巴以及欧美等国的照明产品质量监管体系的特点和有益经验。在此基础上,提出了建立健全我国照明产品质量监管体系的若干建议。  相似文献   
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