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基于车联网的轻型汽油车排放估计
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作者 胡杰 曾德昌 +2 位作者 孙自圆 韦天文 黎业辉 《物流技术》 2017年第9期160-166,共7页
针对目前汽油车排放无法实施有效远程监控的问题,提出了一种基于车联网的汽油车排放估计方法。选用径向基神经网络作为排放估计模型建立的基础,以速度、加速度和发动机功率作为模型的输入量,以不同工况的仿真数据为训练样本,采用资源分... 针对目前汽油车排放无法实施有效远程监控的问题,提出了一种基于车联网的汽油车排放估计方法。选用径向基神经网络作为排放估计模型建立的基础,以速度、加速度和发动机功率作为模型的输入量,以不同工况的仿真数据为训练样本,采用资源分配网络算法(RAN)确定隐层节点数,通过剪枝策略简化网络,以改进的粒子群算法(MPSO)对网络参数进行全局最优搜索优化模型。结合自主研发的车辆信息远程采集系统实现远程数据采集,将远程采集的状态数据导入排放估计模型实现远程排放估计。最后,通过车辆实际道路排放测试实验,将排放估计模型输出结果实验数据对比分析,验证了该排放估计方法的有效性。 展开更多
关键词 车联网 RBF神经网络 排放估计
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基于改进支持向量机的公共建筑碳排放量估计研究
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作者 吴彬锋 黄剑 +2 位作者 杨世旺 詹子仪 汪力 《环境科学与管理》 CAS 2024年第9期21-25,46,共6页
目前,进行公共建筑碳排放量估计时,存在估计精度低和模型稳定性差的问题,对此,提出基于改进支持向量机的公共建筑碳排放量估计研究方法。首先,分析公共建筑碳排放量的影响因素,并对采集到的公共建筑碳排放数据展开预处理;然后,建立支持... 目前,进行公共建筑碳排放量估计时,存在估计精度低和模型稳定性差的问题,对此,提出基于改进支持向量机的公共建筑碳排放量估计研究方法。首先,分析公共建筑碳排放量的影响因素,并对采集到的公共建筑碳排放数据展开预处理;然后,建立支持向量机模型,并基于人工鱼群算法对支持向量机参数进行优化。最后将优化后的正则化参数和宽度参数代入支持向量机中,得到公共建筑碳排放量。实验结果表明,所提方法的PCC系数最高达到0.81,MAE最低值为0.08,MAPE最低值为19%,由此可见所提方法可精准的完成碳排放量估计,同时具有较高的稳定性。 展开更多
关键词 支持向量机 人工鱼群算法 公共建筑 参数优化 排放估计
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基于比功率法的信号控制交叉口排队车辆尾气排放估计 被引量:17
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作者 高云峰 胡华 《中国公路学报》 EI CAS CSCD 北大核心 2015年第4期101-108,共8页
为了优化信号控制参数以降低机动车在交叉口上的尾气排放,分别根据排队车辆的减速工况、怠速工况、加速工况,按照比功率法建立了一种新颖的反推估计方法,定量估计信号控制交叉口前排队车辆的尾气排放总量,并建立了信号控制参数优化的尾... 为了优化信号控制参数以降低机动车在交叉口上的尾气排放,分别根据排队车辆的减速工况、怠速工况、加速工况,按照比功率法建立了一种新颖的反推估计方法,定量估计信号控制交叉口前排队车辆的尾气排放总量,并建立了信号控制参数优化的尾气排放评价依据,最后应用建立的模型对某个单点定时信号控制交叉口前排队车辆的尾气排放进行了估计。研究结果表明:该方法能依据比功率计算公式反推出加速过程和减速过程经历的所有比功率区间对应的时间长度;可根据车辆的到达和离去特征、信号配时参数计算每周期的总停车次数和平均停车延误,以此作为受信号控制影响的停车车辆总数及怠速工况对应的时间长度;应用该方法估计尾气排放是可行的。 展开更多
关键词 交通工程 尾气排放估计 反推估计 排队车辆 定时信号控制
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LDAR检测对石油化工挥发性有机物排放影响
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作者 车达 《中国仪器仪表》 2023年第9期69-72,共4页
LDAR技术是根据动态循环封闭处置作业模式,预估出石化企业VOCs比例的排放等级,它是建立与原油泄漏评价作业相一致的管理规范。以设备的各个检测周期评估分析为出发点,对在该周期中出现的各项数据展开分析,并与检测周期中的范围相联系,... LDAR技术是根据动态循环封闭处置作业模式,预估出石化企业VOCs比例的排放等级,它是建立与原油泄漏评价作业相一致的管理规范。以设备的各个检测周期评估分析为出发点,对在该周期中出现的各项数据展开分析,并与检测周期中的范围相联系,对年排放量的总体影响比例进行计算,并与企业发展的VOCs总排放价值标准要求相结合,对其进行分析,确定在该过程中对其进行密封点要素的评估和配置,再进行相应的调整,从而制定出与实际操作相一致的标准要求。根据测定后的废气比例,对扬程进行了预估。在维修作业中,应注重提升LDAR数据释放的准确性,降低各类安全风险,并调节材料损耗。 展开更多
关键词 低辐射雷达 监测阶段 排放估计
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煤焦化生产过程甲烷排放初步研究 被引量:3
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作者 何秋生 范晓周 +4 位作者 王新明 钱天伟 郭勇义 盛国英 傅家谟 《地球与环境》 CAS CSCD 北大核心 2009年第3期254-257,共4页
本研究选取山西省具有代表性的焦化厂,通过在废气排放烟囱上采集燃烧室废气和装煤/出焦废气,初步研究了煤焦化过程甲烷排放特征。结果显示燃烧室废气中CH4占∑(CH4+NMHC)的比例远高于装煤和出焦废气。基于EPA AP-42排放因子的计算方法,... 本研究选取山西省具有代表性的焦化厂,通过在废气排放烟囱上采集燃烧室废气和装煤/出焦废气,初步研究了煤焦化过程甲烷排放特征。结果显示燃烧室废气中CH4占∑(CH4+NMHC)的比例远高于装煤和出焦废气。基于EPA AP-42排放因子的计算方法,煤焦化三个工段的CH4排放因子为228.5±56.1g/t。结合中国机械炼焦炉焦炭产量,2004年中国机械炼焦CH4排放为0.03Tg/a,占中国总CH4排放的0.1%,可能是山西省除煤炭开采外的重要甲烷排放源,该值还需再进一步的工作中完善和验证。 展开更多
关键词 焦化生产 甲烷 排放估计
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中国稻田甲烷排放研究进展 被引量:37
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作者 蔡祖聪 《土壤》 CAS CSCD 北大核心 1999年第5期266-269,共4页
本文简要地介绍了我国稻田甲烷排放研究的最近进展。分析稻田甲烷排放观察结果表明,在我国冬季排水良好的稻田中,冬季降水量与稻田甲烷排放量存在极显著的指数关系。将我国稻田划分成冬季排水良好与冬季灌水二类,并分别估计其甲烷排... 本文简要地介绍了我国稻田甲烷排放研究的最近进展。分析稻田甲烷排放观察结果表明,在我国冬季排水良好的稻田中,冬季降水量与稻田甲烷排放量存在极显著的指数关系。将我国稻田划分成冬季排水良好与冬季灌水二类,并分别估计其甲烷排放量为4 .21 和3.39Tg CH4 。面积占12 % 的冬灌田排放的甲烷占总排放量(7 .60TgCH4) 的45 % 。 展开更多
关键词 稻田 甲烷排放 排放估计 中国
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澳大利亚核算与报告温室气体排放的审计实践及其借鉴 被引量:1
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作者 张艳芳 陈楠 倪东生 《财会通讯》 北大核心 2022年第5期151-155,161,共6页
十九届四中全会指出要加强生态环境监测和评价制度,强化节能减排等约束性指标管理。加强对核算和报告温室气体排放估计与预测的审计是顺应这一目标的战略需求。澳大利亚审计署对核算和报告温室气体排放估计与预测的审计实践对我国开展... 十九届四中全会指出要加强生态环境监测和评价制度,强化节能减排等约束性指标管理。加强对核算和报告温室气体排放估计与预测的审计是顺应这一目标的战略需求。澳大利亚审计署对核算和报告温室气体排放估计与预测的审计实践对我国开展温室气体审计具有较好的借鉴意义。本文从九个方面分析了澳大利亚核算和报告温室气体排放的审计重点,在此基础上提出我国的温室气体排放审计路径应从加快推进对核算和报告温室气体排放估计和预测的审计、重点加强对核算和报告温室气体排放估计与预测管理流程的审计、着力加强对核算和报告温室气体排放估计与预测管理部门领导履责情况的审计三个方面进行优化。 展开更多
关键词 温室气体排放 审计清单估计排放 预测核算和报告
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Estimation of the Aircraft CO_2 Emissions of China's Civil Aviation during 1960-2009 被引量:1
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作者 HE Ji-Cheng XU Yu-Qing 《Advances in Climate Change Research》 SCIE 2012年第2期99-105,共7页
Based on data collected by Chinese Civil Aviation Statistic Center, the annual CO2 emissions of aircrafts during 1960-2009 were calculated, and the emission intensity and its dynamic characteristics were analyzed. The... Based on data collected by Chinese Civil Aviation Statistic Center, the annual CO2 emissions of aircrafts during 1960-2009 were calculated, and the emission intensity and its dynamic characteristics were analyzed. The results show that the total CO2 emissions of aircrafts in China increased from 120×10^3 t in 1960 to 41.44×10^6 t in 2009. The CO2 emission intensity decreased from 2.9 kg (converted t kra)-1 in 1960 to 0.96 kg (converted t km)-1 in 2009 at an average rate of 0.04 kg (converted t km)-I per year. The average share of CO2 emissions of aircrafts on the total CO2 emissions from the sector of transportation, storage and post was 6.6% during 1980-2005, and 0.25% on the total emissions from fossil fuel combustion during 1971-2008. 展开更多
关键词 China civil aviation energy consumption of aircraft C02 emissions
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Anthropogenic Direct Radiative Forcing of Tropospheric Ozone and Aerosols in 1850 and 2000 Estimated with IPCC AR5 Emissions Inventories 被引量:6
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作者 CHANG Wen-Yuan LIAO Hong 《Atmospheric and Oceanic Science Letters》 2009年第4期201-207,共7页
This study estimates direct radiative forcing by tropospheric ozone and all aerosols between the years 1850 and 2000, using the new IPCC AR5 (the Intergovernmental Panel on Climate Change Fifth Assessment Report) em... This study estimates direct radiative forcing by tropospheric ozone and all aerosols between the years 1850 and 2000, using the new IPCC AR5 (the Intergovernmental Panel on Climate Change Fifth Assessment Report) emissions inventories and a fully coupled chemistry-aerosol general circulation model. As compared to the previous Global Emissions Inventory Activity (GEIA) data, that have been commonly used for forcing estimates since 1990, the IPCC AR5 emissions inventories report lower anthropogenic emissions of organic carbon and black carbon aerosols and higher sulfur and NOx emissions. The simulated global and annual mean burdens of sulfate, nitrate, black carbon (BC), primary organic aerosol (POA), secondary organic aerosol (SOA), and ozone were 0.79, 0.35, 0.05, 0.49, 0.34, and 269 Tg, respectively, in the year 1850, and 1.90, 0.90, 0.11, 0.71, 0.32, and 377 Tg, respectively, in the year 2000. The estimated annual mean top of the atmosphere (TOA) direct radiative forcing of all anthropogenic aerosols based on the AR5 emissions inventories is -0.60 W m^-2 on a global mean basis from 1850 to 2000. However, this is -2.40 W m-2 when forcing values are averaged over eastern China (18-45°N and 95-125°E). The value for tropospheric ozone is 0.17 W m^-1 on a global mean basis and 0.24 W m^-2 over eastern China. Forcing values indicate that the climatic effect of aerosols over eastern China is much more significant than the globally averaged effect. 展开更多
关键词 IPCC AR5 emissions inventories AEROSOLS tropospheric ozone direct radiative forcing
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Estimation of CO_2 Emissions of Locomotives in China(1975-2005) 被引量:1
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作者 Jicheng He Yaozeng Li 《Advances in Climate Change Research》 SCIE 2010年第1期40-45,共6页
Based on annual statistical data collected by the Chinese Railway Statistic Center, the CO2 emissions of locomotives during 1975-2005 were calculated and the emission intensity and its dynamic characteristics were ana... Based on annual statistical data collected by the Chinese Railway Statistic Center, the CO2 emissions of locomotives during 1975-2005 were calculated and the emission intensity and its dynamic characteristics were analyzed. The results show that the CO2 emissions of steam locomotives decreased while that of diesel locomotives increased with time, due to the continuous shift from steam to diesel and electric locomotives. The total CO2 emissions of steam and diesel locomo- tives in China decreased from 42.23 Mt in 1975 to 16.40 Mt in 2005. The emission intensity of CO2 from the two kinds of locomotives decreased at an average rate of 2.4 g (converted t kin)-1 per year. The percentage of the CO2 emissions of locomotives to the total CO2 emissions in the sector of transportation, storage and post in China also decreased persistently from 1980 to 2005. 展开更多
关键词 LOCOMOTIVES CO2 emission emission intensity
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Estimate of China's energy carbon emissions peak and analysis on electric power carbon emissions 被引量:6
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作者 WANG Zhi-Xuan ZHANG Jing-Jie +2 位作者 PAN Li YANG Fan SHI Li-Na 《Advances in Climate Change Research》 SCIE 2014年第4期181-188,共8页
China's energy carbon emissions are projected to peak in 2030 with approximately 110% of its 2020 level under the following conditions: 1) China's gross primary energy consumption is 5 Gtce in 2020 and 6 Gtce in 2... China's energy carbon emissions are projected to peak in 2030 with approximately 110% of its 2020 level under the following conditions: 1) China's gross primary energy consumption is 5 Gtce in 2020 and 6 Gtce in 2030; 2) coal's share of the energy consumption is 61% in 2020 and 55% in 2030; 3) non-fossil energy's share increases from 15% in 2020 to 20% in 2030; 4) through 2030, China's GDP grows at an average annual rate of 6%; 5) the annual energy consumption elasticity coefficient is 0.30 in average; and 6) the annual growth rate of energy consumption steadily reduces to within 1%. China's electricity generating capacity would be 1,990 GW, with 8,600 TW h of power generation output in 2020. Of that output 66% would be from coal, 5% from gas, and 29% from non-fossil energy. By 2030, electricity generating capacity would reach 3,170 GW with 11,900 TW h of power generation output. Of that output, 56% would be from coal, 6% from gas, and 37% from non-fossil energy. From 2020 to 2030, CO2 emissions from electric power would relatively fall by 0.2 Gt due to lower coal consumption, and rela- tively fall by nearly 0.3 Gt with the installation of more coal-fired cogeneration units. During 2020--2030, the portion of carbon emissions from electric power in China's energy consumption is projected to increase by 3.4 percentage points. Although the carbon emissions from electric power would keep increasing to 118% of the 2020 level in 2030, the electric power industry would continue to play a decisive role in achieving the goal of increase in non-fossil energy use. This study proposes countermeasures and recommendations to control carbon emissions peak, including energy system optimization, green-coal-fired electricity generation, and demand side management. 展开更多
关键词 Energy consumption Growth rate Carbon emissions peak Electric power development
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Fatigue Crack Initiation Sizing Using Acoustic Emission
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作者 Azadeh Keshtgar Mohammad Modarres 《Journal of Civil Engineering and Architecture》 2017年第12期1112-1122,共11页
One of the major concerns in structures is early detection of a growing crack to prevent fracture, predict remaining useful life, schedule maintenance and reduce costly downtimes. AE (acoustic emission) is a non-des... One of the major concerns in structures is early detection of a growing crack to prevent fracture, predict remaining useful life, schedule maintenance and reduce costly downtimes. AE (acoustic emission) is a non-destructive testing method with potential applications for locating and monitoring fatigue cracks. This paper focuses on in-situ monitoring of structural health, specifically detection of small crack growth and crack initiation in structures using AE technology. A probabilistic AE-based model for small fatigue cracks was developed and the uncertainties of the model were estimated. The paper discusses the methodology used, experimental approach, results obtained and predictive models developed.The developed model can be used to evaluate the integrity of structures and assess structural health by estimating the probability density function of the length of detected cracks. The outcome of this research has significant potential to be used for in-situ monitoring and evaluation of structural integrity. 展开更多
关键词 Structural integrity FATIGUE crack initiation acoustic emission RELIABILITY
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A Contribution to a Better Understanding of Global Land Grabbing's Impact on Employment and Environmental Threats
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作者 Laura Castellucci Marco Arbia 《Journal of Agricultural Science and Technology(A)》 2017年第1期1-10,共10页
In the last two decades, the global interest on farmland grew at a remarkable pace. As a consequence, million hectares of land exchanged hands. The ways the transfers happened combined with their geographic concentrat... In the last two decades, the global interest on farmland grew at a remarkable pace. As a consequence, million hectares of land exchanged hands. The ways the transfers happened combined with their geographic concentration in Sub-Saharian Africa, have earned the phenomenon the name of "land grab". The agricultural sector considered a "sunset industry" when commodities prices were declining, is now attractive to financial investors. These foreign investments may be good as they may improve agricultural productivity or instead bad as they may benefit only financial investors. Some results in terms of environmental and local communities' worsening conditions have already emerged. This paper aims to investigate what drives the big size transfers of land, to empirically estimate their effects in terms of local employment and to assess the environmental effects produced by the rapid transformation in the use of vast amount of land in terms of CO2 emissions. It is also proposed to use the estimation in terms of local employment impact as a way of distinguishing between foreign direct investment and land grabbing. 展开更多
关键词 Land grabbing foreign direct investment land use change CONTRACTS land rights CO2 emissions.
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