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Online learning method for predicting air environmental information used in agricultural robots
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作者 Yueting Wang Minzan Li +3 位作者 Ronghua Ji Minjuan Wang Yao Zhang Lihua Zheng 《International Journal of Agricultural and Biological Engineering》 SCIE 2024年第5期206-212,共7页
Air environmental information plays an important role during plant growth and reproduction, prompt and accurate prediction of atmospheric environmental data is helpful for agricultural robots to make a timely decision... Air environmental information plays an important role during plant growth and reproduction, prompt and accurate prediction of atmospheric environmental data is helpful for agricultural robots to make a timely decision. For efficiency, an online learning method for predicting air environmental information was presented in this work. This method combines the advantages of convolutional neural network (CNN) and experience replay technique: CNN is used to extract features from raw data and predict atmospheric environmental information, experience replay technique can store environmental data over some time and update the hyperparameters of CNN. To validate the effects of this method, this online method was compared with three different predictive methods (including random forest, multi-layer perceptron, and support vector regression) using a public dataset (Jena). According to results, a suitable sample sequence size (e.g., 16) has a smaller number of training sessions and stable results, a larger replay memory size (e.g., 200) can provide enough samples to capture useful features, and 6 d of historical information is the best setting for training predictor. Compared with traditional methods, the method proposed in this study is the only method applied for various conditions. 展开更多
关键词 online learning method conventional neural network real-time prediction air environmental information
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Investigating the Air Quality Parameters in Louisiana’s Industrial Corridor: A Baton Rouge Case Study
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作者 Oluwafemi Awolesi Peter G. Oni +5 位作者 Oluwatoyin K. Adekoya Seyi B. Adekoya Oluwafeyikemi D. Ogunmusi Fatemeh Ghafari Abosede Oje Odunayo Lawal 《Journal of Geoscience and Environment Protection》 2024年第7期139-164,共26页
In a local context, sustainable development entails utilizing the current resources—material and immaterial, measurable and immeasurable, popular and unpopular—of the community in a manner that avoids overexploitati... In a local context, sustainable development entails utilizing the current resources—material and immaterial, measurable and immeasurable, popular and unpopular—of the community in a manner that avoids overexploitation and ensures intergenerational equity. This approach prioritizes the safety and health of local citizens, placing communal productivity above corporate profitability. This research aims to assess air quality surrounding 28 chemical industry sites in Baton Rouge, Louisiana, to understand the environmental and health impacts of industrial pollutants, with a focus on environmental justice. Air quality pollutants, including PM2.5, PM10, O3, NO2, CO, and SO2, were monitored for 75 days during the Summer, using the BreezoMeter app. Python, Mapize, and QGIS software technologies were utilized for data analysis and visualization. Findings indicate a reduction in NO2 and CO levels, compared to existing literature. However, the persistent challenge of particulate matter suggests areas for further environmental management efforts. Additionally, the research suggests a significant disparity in air pollution exposure, probably affecting marginalized communities. Although the nature of the study might not fully capture annual pollution trends, the findings highlight the urgent need for the chemical industry to adopt efficient production methods and for policymakers to enhance air quality standards and enforcement, particularly in pollution-sensitive areas. The disproportionate impact of air pollution on vulnerable communities calls for a more inclusive approach to environmental justice, ensuring equitable distribution of clean air benefits and community involvement in pollution management decisions. 展开更多
关键词 air Quality Monitoring Chemical Industry Pollution environmental Justice Health Implications Particulate Matter Case Study
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Questionnaire Research on Indoor Environment Quality i n China 被引量:3
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作者 朱能 刘俊杰 《Transactions of Tianjin University》 EI CAS 2003年第2期157-160,共4页
With 1 185 pi eces of questionnaire, it is found that in China, people take fresh air, odor, e tc., as well as indoor air temperature, humidity, as the most important indoor a ir parameters. It is also found that ther... With 1 185 pi eces of questionnaire, it is found that in China, people take fresh air, odor, e tc., as well as indoor air temperature, humidity, as the most important indoor a ir parameters. It is also found that there is a significant sensitivity differen ce in indoor environment between southerners and northerners in China. People fr om different regions have different demands for their working and living environ ment. Therefore, as a good design of air conditioning system, it is strongly rec ommended that the different demands of people from different regions should be t aken into consideration. 展开更多
关键词 indoor air environment QUESTIONNairE thermal comfort
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Big Data Analytics with Artificial Intelligence Enabled Environmental Air Pollution Monitoring Framework 被引量:1
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作者 Manar Ahmed Hamza Hadil Shaiba +5 位作者 Radwa Marzouk Ahmad Alhindi Mashael M.Asiri Ishfaq Yaseen Abdelwahed Motwakel Mohammed Rizwanullah 《Computers, Materials & Continua》 SCIE EI 2022年第11期3235-3250,共16页
Environmental sustainability is the rate of renewable resourceharvesting, pollution control, and non-renewable resource exhaustion. Airpollution is a significant issue confronted by the environment particularlyby high... Environmental sustainability is the rate of renewable resourceharvesting, pollution control, and non-renewable resource exhaustion. Airpollution is a significant issue confronted by the environment particularlyby highly populated countries like India. Due to increased population, thenumber of vehicles also continues to increase. Each vehicle has its individualemission rate;however, the issue arises when the emission rate crosses thestandard value and the quality of the air gets degraded. Owing to the technological advances in machine learning (ML), it is possible to develop predictionapproaches to monitor and control pollution using real time data. With thedevelopment of the Internet of Things (IoT) and Big Data Analytics (BDA),there is a huge paradigm shift in how environmental data are employed forsustainable cities and societies, especially by applying intelligent algorithms.In this view, this study develops an optimal AI based air quality prediction andclassification (OAI-AQPC) model in big data environment. For handling bigdata from environmental monitoring, Hadoop MapReduce tool is employed.In addition, a predictive model is built using the hybridization of ARIMAand neural network (NN) called ARIMA-NN to predict the pollution level.For improving the performance of the ARIMA-NN algorithm, the parametertuning process takes place using oppositional swallow swarm optimization(OSSO) algorithm. Finally, Adaptive neuro-fuzzy inference system (ANFIS)classifier is used to classify the air quality into pollutant and non-pollutant.A detailed experimental analysis is performed for highlighting the betterprediction performance of the proposed ARIMA-NN method. The obtainedoutcomes pointed out the enhanced outcomes of the proposed OAI-AQPCtechnique over the recent state of art techniques. 展开更多
关键词 SUSTAINABILITY environmental air quality predictive model pollution monitoring statistical models artificial intelligence
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Analysis of the Ambient Air Quality of Tarlac City: Baseline Data for Environmental Management Plan 被引量:1
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作者 Xyris Gerard A. Fernandez Lolita V. Sicat Maria Elena D. David 《材料科学与工程(中英文A版)》 2011年第1X期64-70,共7页
关键词 环境管理计划 空气质量分析 基准数据 空气污染物 环境空气监测 城市中心 呼吸系统疾病 总悬浮微粒
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Analysis of the relationship between environmental policies and air quality during major social events
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作者 Ruiliang Zhang Guoqing Shi 《Chinese Journal of Population,Resources and Environment》 2016年第3期167-173,共7页
Based on an analysis of major recent social events in China,such as the 2008 Beijing Olympic Games,2010 Shanghai World Expo,2014 Nanjing Youth Olympic Games,and 2014 Beijing Asia Pacific Economic Cooperation Conferenc... Based on an analysis of major recent social events in China,such as the 2008 Beijing Olympic Games,2010 Shanghai World Expo,2014 Nanjing Youth Olympic Games,and 2014 Beijing Asia Pacific Economic Cooperation Conference,mandatory,temporary,and indemnificatory quantitative policies aimed at protecting air quality,which were carried out by both central and local governments,made substantial contributions to changes and improvements in air quality.To some extent,the findings show that command and control measures play a significant role in protecting air quality,while the law and economic and voluntary environmental safeguard measures do not during major social events.Therefore,it reminds us the air quality could and will improve not only during major social events but also in the regular days if we implement appropriate environmental policies and safeguard measures. 展开更多
关键词 Major social events environmental policy air quality command and control measures
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Oxidation Performance of Ytterbium Disilicate/Silicon Environmental Barrier Coating via Optimized Air Plasma Spraying 被引量:1
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作者 Yingjie Jian Yanfei Wang +1 位作者 Rongjun Liu Fan Wan 《Journal of Materials Science and Chemical Engineering》 2021年第4期19-26,共8页
<div style="text-align:justify;"> Environmental barrier coatings (EBCs) play a critical role in mitigating the degradation of SiC<sub>f</sub>/SiC ceramic matrix composites (CMCs) in complex... <div style="text-align:justify;"> Environmental barrier coatings (EBCs) play a critical role in mitigating the degradation of SiC<sub>f</sub>/SiC ceramic matrix composites (CMCs) in complex combustion environment, and improve the service life of thermal engine components. In this paper, by adjusting the parameters of atmospheric plasma spraying (APS), the spraying process of ytterbium disilicate (Yb<sub>2</sub>Si<sub>2</sub>O<sub>7</sub>) under a lower power has been optimized. A two-layer EBC system consisting of ytterbium disilicate and silicon is prepared on the SiC<sub>f</sub>/SiC composite substrate by using optimized technological parameters. The thermal resistance and water oxygen corrosion resistance of such two-layer EBC system are investigated. The results indicate that the current ytterbium disilicate/silicon EBC system exhibits good phase stability, excellent water vapor and oxygen corrosion resistance. However, the exposed silicon bonding layer tends to generate an excessive thermal growth oxide (TGO) layer known as SiO<sub>2</sub>, leading to an early spallation of the coating. </div> 展开更多
关键词 environmental Barrier Coating air Plasma Spraying Ytterbium Disilicate SiCf/SiC Composites
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Analysis of the Game for the Air Pollution in the Perspective of the Amendment about Environmental Law
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作者 Yang Yang 《Meteorological and Environmental Research》 CAS 2014年第10期22-24,共3页
The haze has become the necessary thing to talk about everywhere for the Chinese people nowadays and the main report object in the news. It becomes increasingly urgent to develop the circular economy and build a beaut... The haze has become the necessary thing to talk about everywhere for the Chinese people nowadays and the main report object in the news. It becomes increasingly urgent to develop the circular economy and build a beautiful China. But there exists secretly a game between the central and local governments when the air protection is enforced. The central government calls for implementing the total control system of the key pollutant emission,but the local governments are blandly ignoring the central government's requirement as they have to face the pressures of the assessment and performance. And the games among the local governments at the same level and between the governments and enterprises lead that the existing incentive policy through the legislation is inefficiency in China. The amendment about Environmental Law has laid foundation of the legal system for it. 展开更多
关键词 The amendment about environmental Law The game air pollution China
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Research on Decision Support System (DSS) of Atmospheric Environment Management in Anhui Province Based on Air Quality Forecasting
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作者 Geng Tianzhao Ji Mian +4 位作者 Zhu Yu Wang Huan Dong Hao Zhao Xuhui Cheng Long 《Meteorological and Environmental Research》 CAS 2018年第4期61-65,共5页
With the atmospheric stereoscopic monitoring, air quality forecasting and decision of environment management as the main line, and comprehensive management system as the guidance, five platforms including infrastruct... With the atmospheric stereoscopic monitoring, air quality forecasting and decision of environment management as the main line, and comprehensive management system as the guidance, five platforms including infrastructure, technological support, monitoring and early monitoring, decision support and information services were established. These platforms have 15 subsystems, including stereoscopic monitoring network, visual business consultation, high-performance computing environment, comprehensive management of atmospheric data, emission inventories of pollu-tion sources, evaluation tools of atmospheric models, monitoring and management of air pollution, forecasting and early warning of air quality, diag-nostic analysis of atmospheric environment, tracking of air pollution sources, emergency management of air pollution, conformity management of air quality, comprehensive display of information, releasing of information to external networks, and releasing of information by mobile networks. The decision support system (DSS) of atmospheric environment management could realize an integration business system of 11 air quality forecast - heavy pollution weather warning - diagnosis of pollution causes (dynamic analysis of pollution sources) -air quality conformity planning (air pollu-tion emergency management) -evaluation of forecasting and warning results (evaluation pf management measures) -air quality forecasting" and provide the technical support for the prevention and control of atmosphere pollution in Anhui province. 展开更多
关键词 Atmospheric stereoscopic monitoring air quality forecasting Decision of environmental management
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空空导弹海洋大气自然环境试验研究 被引量:1
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作者 张艳辉 史明丽 黄帅军 《装备环境工程》 CAS 2024年第3期11-15,共5页
针对空空导弹随航母服役需求和海洋大气自然环境适应性风险,结合相关标准和研制经验,对空空导弹海洋大气自然环境试验方案设计流程、方法及要点进行了研究。提出了一套空空导弹海洋大气自然环境试验方案,可用于指导新研型号科学有效地... 针对空空导弹随航母服役需求和海洋大气自然环境适应性风险,结合相关标准和研制经验,对空空导弹海洋大气自然环境试验方案设计流程、方法及要点进行了研究。提出了一套空空导弹海洋大气自然环境试验方案,可用于指导新研型号科学有效地开展自然环境试验,为回答空空导弹海洋大气自然环境适应性指标提供了支撑。空空导弹应系统策划海洋大气自然环境试验,以尽早暴露问题,实现产品设计改进,为上舰环境适应性的提高奠定基础。同时,还应大力开展自然加速环境试验技术和动态自然环境试验技术研究工作。 展开更多
关键词 空空导弹 海洋大气 自然环境试验 试验剖面
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北京市环境空气样品外照射辐射水平与空气质量的关系
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作者 白斌 孟庆华 +7 位作者 王欢 王宏芳 孔玉侠 冯泽臣 俞君 孙亚茹 朱维杰 马永忠 《首都公共卫生》 2024年第3期159-162,共4页
目的探讨大气气溶胶颗粒物外照射辐射水平与空气质量的关系,及时发现环境中可能存在的放射性污染,为建立人群健康监护体系和有效的污染防控策略提供技术基础。方法在北京市东城区某院5层设置固定的环境空气监测点,使用Snow White大流量... 目的探讨大气气溶胶颗粒物外照射辐射水平与空气质量的关系,及时发现环境中可能存在的放射性污染,为建立人群健康监护体系和有效的污染防控策略提供技术基础。方法在北京市东城区某院5层设置固定的环境空气监测点,使用Snow White大流量采样器收集2024年1—2月期间28个监测日的大气气溶胶样品,每日连续20~24 h采样,使用TBM-3S型测量监测仪测量样品滤膜表面的空气比释动能率,分析样品的辐射水平与当日空气质量指数(AQI)、PM_(2.5)和PM_(10)的变化关系。结果2024年1—2月随机抽取28个监测日空气样品的外照射辐射水平范围值为2.10~7.18μGy/h,平均值为(4.72±1.28)μGy/h,样品外照射辐射水平与AQI、PM_(2.5)和PM_(10)的相关系数R2分别为0.0329、0.0135和0.044。2017年38个监测日样品外照射辐射水平范围值为2.52~6.83μGy/h,平均值为(4.46±1.29)μGy/h,2024和2017年两组样品外照射辐射水平比较,差异无统计学意义(t=0.008,P>0.05)。结论北京市大气气溶胶滤膜样品外照射辐射水平与空气质量无直接关系。空气样品外照射辐射水平是环境空气放射性污染监测的可靠指针,应持续进行监测。 展开更多
关键词 环境空气 外照射 辐射水平 空气质量
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中国城市PM_(2.5)污染暴露不平等及其驱动因素——基于Theil指数和LMDI分解 被引量:1
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作者 马本 秦露 夏天辰 《中国环境科学》 EI CAS CSCD 北大核心 2024年第1期555-566,共12页
聚焦大气污染物PM_(2.5),对2015~2021年污染物浓度进行人口规模赋权,构建中国城市PM_(2.5)污染暴露水平指标,基于GINI系数和Theil指数测度污染暴露不平等,并按城市行政层级、省份进行差异分解;基于对数平均迪氏指数分解法(LMDI),分别对... 聚焦大气污染物PM_(2.5),对2015~2021年污染物浓度进行人口规模赋权,构建中国城市PM_(2.5)污染暴露水平指标,基于GINI系数和Theil指数测度污染暴露不平等,并按城市行政层级、省份进行差异分解;基于对数平均迪氏指数分解法(LMDI),分别对污染暴露水平、不平等程度进行驱动因素分解,探究其变化背后的社会经济因素.结果表明:中国城市PM_(2.5)污染暴露不平等总体温和,GINI系数保持在0.2以内且呈递减趋势.不同行政级别城市间未表现出污染暴露不平等,而省际差异对污染暴露不平等的贡献达68.4%;总体上能源的污染暴露乘数、政府绿色支出能耗强度是PM_(2.5)污染暴露水平的主要抑制因素,对污染暴露水平的驱动贡献超过60%.政府支出结构、支出规模、经济发展和人口因素对PM_(2.5)污染暴露起促增作用,但各因素在不同层级的城市间具有异质性;能源的污染暴露乘数、绿色支出能耗强度对不平等的动态抑制作用弱化,主要依靠能源绿色化的治污策略面临挑战.据此提出更好发挥政府作用,持续降低中国PM_(2.5)污染暴露水平,实现环境公共服务更加均等化的政策启示. 展开更多
关键词 大气质量 污染暴露水平 环境不平等 泰尔指数 动态因素分解 PM_(2.5)
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Air Pollution Prediction in Warri and Its Environs Using Quality Parameters
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作者 Akinyemi Olufemi Ogunkeyede Chinonso Oliver Mbaoma +2 位作者 Aluya Duncan Iyogbon Adedoyin Ayorinde Adebayo Efe Jeffery Isukuru 《International Journal of Geosciences》 2023年第6期531-546,共16页
Air pollution is a major environmental problem in the Niger Delta Area (NDA) of Nigeria primarily due to oil and gas-related operational activities. Identifiable sources of air pollution in the NDA include gas flaring... Air pollution is a major environmental problem in the Niger Delta Area (NDA) of Nigeria primarily due to oil and gas-related operational activities. Identifiable sources of air pollution in the NDA include gas flaring, vehicle emissions from internal combustion engines, crude oil pollution, etc. The aim of this research is to evaluate the concentration of air pollutants from crude oil-related activities using air quality parameters in Warri during seasons peculiar to the area of study. The Warri metropolis, one of Nigeria’s largest oil cities, was the sampling region under research in this study. An Aeroqual handheld mobile multi-gas monitor fitted with different sensors of (Carbon Monoxide (CO), air quality multi-meter for Particulate Matter (PM<sub>2.5</sub> and PM<sub>10</sub>), Volatile Organic (VOC), Sulphur dioxide (SO<sub>2</sub>), Ammonia (NH<sub>3</sub>), Methane (CH<sub>4</sub>), and air quality index (AQI), was used for the collection of air quality parameter. Linear regression was used to create the model, which was then used to predict the extent of pollution in the locations of study. The average mean concentrations of air pollutants such as CO, NO<sub>2</sub>, CH<sub>4</sub>, VOC, NH<sub>4</sub>, and SO<sub>2</sub> were measured at all sampling sites during wet and dry seasons. The results showed that the levels of these pollutants were above the WHO permissible limits for the majority of the air quality parameters studied in all sixteen locations. The concentration levels of most of the pollutants were higher in the dry season than in the rainy season. The study also found that the pollutants were mainly from fossil fuel combustion and road traffic emissions. Overall, the research provided monitoring data for all air quality pollutants under investigation in the study area and demonstrated that these concentrations exceed regulatory guidelines. 展开更多
关键词 GEOSTATISTICS air Pollution Fossil Fuel Combustion environmental Monitoring
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2020年重庆市居民空气污染相关环境健康知识、态度、行为现状及影响因素分析
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作者 叶丹 赵怡楠 +2 位作者 闫旭 樊琳 王先良 《环境卫生学杂志》 2024年第11期949-954,共6页
目的 探索重庆市居民空气污染相关环境健康知识、态度、行为的现状及影响因素。方法 于2022年采用立意抽样的方法,通过新媒体微信公众平台发布自我设计的《空气污染居民环健康知信行现状调查问卷》,面向重庆市18~60岁常驻居民开展重污... 目的 探索重庆市居民空气污染相关环境健康知识、态度、行为的现状及影响因素。方法 于2022年采用立意抽样的方法,通过新媒体微信公众平台发布自我设计的《空气污染居民环健康知信行现状调查问卷》,面向重庆市18~60岁常驻居民开展重污染天气公众知信行调查。运用卡方检验、多因素Logistic回归方法分析居民空气污染相关环境健康知识、态度、行为水平差异及影响因素。结果 共调查重庆市的巴南区、北碚区、九龙坡区等15个市辖区居民2 300名,回收问卷2 300份,其中有效问卷2 264份,20.01%的被调查者问卷评分超过70分;不同年龄、不同文化程度、不同职业人群之间的环境健康知信行水平存在差异(χ^(2)分别为177.47、210.26和29.1,P<0.001)。其中文化程度和年龄是影响人群环境健康知信行水平的重要因素。以文化程度为小学及以下的居民为参照,文化程度为初高中、大专及以上的居民具备环境健康知信行水平的OR值分别为3.06和7.28(P<0.001);以年龄≤20岁的居民为参照,年龄在21~30岁和31~45岁的居民环境健康知信行水平的OR值分别为8.97和6.14。结论 2020年重庆市居民空气污染相关环境健康知信行水平有待提高,文化程度和年龄是影响人群环境健康知信行水平的重要因素。 展开更多
关键词 环境健康 空气污染 知信行 防护干预
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针对连续暴露因素的广义倾向评分方法在环境健康领域中的应用
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作者 杜婧 高燕琳 李刚 《环境卫生学杂志》 2024年第1期13-18,共6页
目的介绍针对连续暴露因素的广义倾向评分(GPS)方法原理,探索其在环境健康领域中的应用,为测量环境健康风险提供有效工具。方法利用北京市“空气污染与人群健康队列研究”基线调查数据(2017—2018年),评价针对连续暴露因素的GPS方法在... 目的介绍针对连续暴露因素的广义倾向评分(GPS)方法原理,探索其在环境健康领域中的应用,为测量环境健康风险提供有效工具。方法利用北京市“空气污染与人群健康队列研究”基线调查数据(2017—2018年),评价针对连续暴露因素的GPS方法在大气污染对健康效应估计中的应用效果。结果应用针对连续暴露水平的GPS方法后,不同暴露水平人群的混杂因素均衡性得到明显改善。PM_(2.5)暴露每增加10μg/m^(3),高血压患病的风险增加比例从原来的10.3%上升到11.9%。结论针对连续暴露水平的GPS方法在一定程度上为大气污染与健康的关联研究提供更准确的流行病学证据。 展开更多
关键词 广义倾向评分 环境健康 大气污染 混杂因素 高血压
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空间站舱内微量有害气体状态评价和流转分析
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作者 杨润泽 王传增 +4 位作者 卞强 周国栋 刘向阳 吴志强 杨松林 《航天器环境工程》 CSCD 2024年第3期283-289,共7页
文章聚焦于中国空间站长期在轨运行中微量有害气体的整体状态和控制情况,阐述了微量有害气体随舱内物质循环向冷凝水回收净化以及CO_(2)去除和还原等环节流转的规律。通过在轨状态分析、地面比对评估试验结果和流转特性分析,说明中国空... 文章聚焦于中国空间站长期在轨运行中微量有害气体的整体状态和控制情况,阐述了微量有害气体随舱内物质循环向冷凝水回收净化以及CO_(2)去除和还原等环节流转的规律。通过在轨状态分析、地面比对评估试验结果和流转特性分析,说明中国空间站各净化系统对舱内微量污染物成分进行了有效控制,舱内空气中微量有害气体浓度保持在较低水平。研究旨在为后续微量有害气体净化环节的运行和监测提供指导。 展开更多
关键词 中国空间站 舱内环境控制 微量有害气体 空气净化 评估试验
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惯例转移要素分析:来自京津冀地区大气污染治理利基项目间学习的实证研究
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作者 王江 王丽娟 《东北大学学报(社会科学版)》 CSSCI 北大核心 2024年第2期48-57,128,共11页
针对项目间学习的惯例转移进行研究,梳理了惯例转移的概念及内涵,从理论上探讨惯例转移与内外部环境、知识能力以及团队互动之间的相互作用。基于主成分分析和随机森林模型,构建影响惯例转移的重要因素组合,通过对要素的相互作用和关系... 针对项目间学习的惯例转移进行研究,梳理了惯例转移的概念及内涵,从理论上探讨惯例转移与内外部环境、知识能力以及团队互动之间的相互作用。基于主成分分析和随机森林模型,构建影响惯例转移的重要因素组合,通过对要素的相互作用和关系的定量化分析,以评价惯例转移难易程度。通过2015—2019年京津冀大气污染治理惯例转移定量分析,发现惯例转移受不同环境要素影响,并且处在不断进化的学习过程中。知识资源、经济环境对于多数惯例转移是重要的、起作用的要素,易于在其他环境中发生转移,而末端型治理增加了知识资源(通用知识)的转移难度。自然资源和自然环境等要素是惯例转移过程的主要冲突因素,使惯例难以在其他环境中发生转移。 展开更多
关键词 惯例转移 项目间学习 大气污染治理 要素分析 环境要素组合
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基于硅酸镁前处理富集的气相色谱-串联质谱分析方法检测空气中9种挥发性N-亚硝胺 被引量:1
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作者 杨振 何婷婷 +2 位作者 张忠堂 徐晨 陈武炼 《分析科学学报》 CAS CSCD 北大核心 2024年第3期350-355,共6页
针对空气中N-亚硝胺检测困难、成本高的问题,通过硅酸钠对廉价的无定形二氧化硅进行刻蚀,与硫酸镁反应得到硅酸镁负载填料,将其装入柱管制得N-亚硝胺捕集器,与气相色谱-串联质谱(GC-MS/MS)联用建立了一种检测空气中9种挥发性N-亚硝胺的... 针对空气中N-亚硝胺检测困难、成本高的问题,通过硅酸钠对廉价的无定形二氧化硅进行刻蚀,与硫酸镁反应得到硅酸镁负载填料,将其装入柱管制得N-亚硝胺捕集器,与气相色谱-串联质谱(GC-MS/MS)联用建立了一种检测空气中9种挥发性N-亚硝胺的分析方法。本方法前处理步骤简单,富集后的洗脱液即可进入仪器分析。对影响方法回收率的色谱柱类型、升温程序、定性定量离子对和洗脱溶剂等参数进行了优化。在最佳实验条件下,9种挥发性N-亚硝胺的线性范围为50~5 000 ng/m^(3),最低检出限为11 ng/m^(3)。在实际空气样品检测中,9种挥发性N-亚硝胺回收率为96.8%~105.6%,RSD为3.8%~8.8%。这表明,以该易制备、低成本的硅酸镁负载填料填充的小柱,能替代价格昂贵的商品化亚硝胺捕集器(94.7%~103.2%),且与普适性更强的GC-MS/MS联用建立的检测方法,能够应用于空气中9种挥发性亚硝胺的检测。 展开更多
关键词 硅酸镁修饰的二氧化硅 气相色谱-串联质谱 挥发性N-亚硝胺 空气环境监测
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面向空天地一体化网络的数字孪生技术架构及应用 被引量:1
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作者 李媛 费泽松 +3 位作者 晁子云 黄靖轩 李斌 郑重 《移动通信》 2024年第1期95-102,共8页
详细探讨了数字孪生技术在空天地一体化通信中的具体架构,以及网络优化方面的应用。将数字孪生分为虚拟空天地一体化网络和智能决策层。虚拟网络是对物理空天地通信网的精准映射,支持实时监控和测试验证功能。在智能决策层,通过环境感... 详细探讨了数字孪生技术在空天地一体化通信中的具体架构,以及网络优化方面的应用。将数字孪生分为虚拟空天地一体化网络和智能决策层。虚拟网络是对物理空天地通信网的精准映射,支持实时监控和测试验证功能。在智能决策层,通过环境感知与业务预测实现网络优化。最后,验证了面向空天地一体化的数字孪生技术在动态通信网络优化中的巨大潜力,为网络优化的未来发展提供了创新思路。 展开更多
关键词 数字孪生技术 空天地一体化网络 环境感知 业务预测 网络优化
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安徽省三市大气污染物和绿地暴露对初治结核病患者病亡率的影响
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作者 赵嘉文 张永忠 +5 位作者 李振华 毛毅铖 张菁菁 胡成洋 张秀军 阚晓红 《中国防痨杂志》 CAS CSCD 北大核心 2024年第1期75-84,共10页
目的:探讨大气污染物和绿地暴露对初治结核病患者治疗期间病亡率的影响,从环境监测层面上为结核病患者的健康管理提供科学依据。方法:收集安徽省合肥市、淮南市、黄山市2015年1月1日至2020年12月31日的29519例初治结核病患者的数据。通... 目的:探讨大气污染物和绿地暴露对初治结核病患者治疗期间病亡率的影响,从环境监测层面上为结核病患者的健康管理提供科学依据。方法:收集安徽省合肥市、淮南市、黄山市2015年1月1日至2020年12月31日的29519例初治结核病患者的数据。通过环境监测站收集大气污染物细颗粒物[空气动力学直径≤2.5μm的颗粒(particulate matter with an aerodynamic diameter≤2.5μm,PM_(2.5))]、可吸入颗粒物[空气动力学直径≤10μm的颗粒(particulate matter with an aerodynamic diameter≤10μm,PM_(10))]、一氧化碳(CO)、二氧化氮(NO_(2))数据。应用Cox比例风险模型计算大气污染物暴露与初治结核病患者病亡率的风险比(HR)及其95%置信区间(95%CI),同时结合绿地暴露进行亚组分析。结果:29519例结核病患者中,有369例(1.25%)在治疗期间死亡。多因素Cox回归分析结果显示,PM_(2.5)每增加10μg/m^(3),患者的死亡风险上升15.6%(HR=1.156,95%CI:1.146~1.165),PM_(10)每增加10μg/m^(3),患者的死亡风险上升18.3%(HR=1.183,95%CI:1.176~1.190),CO每增加0.10 mg/m^(3),患者的死亡风险上升6.7%(HR=1.067,95%CI:1.060~1.074),NO_(2)每增加10μg/m^(3),患者的死亡风险上升2.8%(HR=1.028,95%CI:1.019~1.037)。将绿地暴露按照四分位数(Q_(1)~Q_(4))由低到高进行分组后,大气污染物对病亡率的影响随绿地暴露的提升逐渐降低[以PM_(2.5)为例,其在250 m和500 m缓冲区归一化植被指数对病亡率的HR值,Q_(1)分别为1.218(95%CI:1.197~1.240)和1.231(95%CI:1.210~1.253),Q_(4)分别下降至1.125(95%CI:1.106~1.146)和1.138(95%CI:1.118~1.159)]。结论:大气污染物暴露是初治结核病患者治疗期间的危险因素,更高的绿化程度能够降低因暴露于大气污染物所导致的死亡风险。 展开更多
关键词 结核 空气污染物 环境暴露 回顾性研究 因素分析 统计学
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