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181.
随着机动车数量不断增长,车辆尾气排放对人们的影响也在加剧,本文以沈阳市某住宅小区地下停车场的车辆尾气排放实测数据与环评工作中常用的经验预测公式进行比较,分析计算尾气污染物的各预测公式的准确程度;同时,对预测值进行评价时,采用不同空气质量标准得出的达标结论有所不同,以此比较不同标准的适用性,为该类项目的环评提供参考。 相似文献
182.
近年来,全球和区域碳模拟与同化反演系统(简称“碳同化系统”)快速发展,并被广泛应用于不同时空尺度的碳通量和碳汇估算、碳排放量校核研究中,为支撑全球碳盘点提供了关键技术手段。文章回顾了国内外主要碳同化系统的发展历程和应用案例,总结了当前常见的全球和区域碳同化系统的结构和特点,包括使用的大气传输模式、同化方法、空间分辨率等内容;探讨了当前常见模型系统应用中的关键问题、不足与发展方向,以期为碳同化系统应用于我国环境管理和气候变化工作提供参考。 相似文献
183.
Emerging sensors, computers, network technologies, and connected platforms result potentially in an immeasurable collection of data within plant operations. This creates the possibility of solving problems innovatively. Because most of the data appear to be unstructured or semi-structured, organizations shall design and adopt new strategies. Further, workflow architectures with data analytics are needed including machine learning tools and artificial intelligence techniques before proto-type solutions can be developed. We shall discuss several prospects of using (big) data analytics integrated with cloud services to produce solutions for improving plant operations. The paper outlines the vision and a systematic framework highlighting the data analytics lifecycle in the area of plant operation, process safety, and environmental protection. Four rather diverse example case studies are demonstrated including (1) deep learning-based predictive maintenance monitoring modeling, (2) Natural Language Processing (NLP) for mining text, (3) barrier assessment for dynamic risk mapping (DRA), and (4) correlation development for sustainability indicators. It further discusses the challenges in both research and implementation of proposed solutions in the industry. It is concluded that a well-balanced integrated approach including machine supporting decisions integrated with expert knowledge and available information from various key resources is required to enable more informed policy, strategic, and operational risk decision-making leading to safer, reliable and more efficient operations. 相似文献
184.
Marcela Rojas Felipe Quintero Witold F. Krajewski 《Journal of the American Water Resources Association》2020,56(4):568-585
This paper explores the performance of the analysis‐and‐assimilation configuration of the National Water Model (NWM) v1.0 in Iowa. The NWM assimilates streamflow observations from the United States Geological Survey (USGS), which increases the performance but also limits the available data for model evaluation. In this study, Iowa Flood Center Bridge Sensors (IFCBS) data provided an independent nonassimilated dataset for evaluation analyses. The authors compared NWM outputs for the period between May 2016 and April 2017, with two datasets: USGS streamflow and velocity observations; Stage and streamflow data from IFCBS. The distribution of Spearman rank correlation (rs), Nash–Sutcliffe efficiency (E), and Kling–Gupta efficiency (KGE) provided quantification of model performance. We found the performance was linked with the spatial scale of the basins. Analysis at USGS gauges showed the strongest performance in large (>10,000 km2) basins (rs = 0.9, E = 0.9, KGE = 0.8), with some decrease at small (<1,000 km2) basins (rs = 0.6, E = ?0.25, KGE = ?0.2). Analysis with independent IFCBS observations was used to report performance at large basins (rs = 0.6, KGE = 0.1) and small basins (rs = 0.2, KGE = ?0.4). Data assimilation improves simulations at downstream basins. We found differences in the characterization of the model and observed data flow velocity distributions. The authors recommend checking the connection of USGS gauges and NHDPlus reaches for selected locations where performance is weak. 相似文献
185.
在气象污染方面,不同区域气象环境污染不同,各个地区的信息关联性微弱,导致现地区气象环境污染指数测量设备无法对其他区域污染信息准确检测,因此,本文通过提出以物联网技术为支持的跨区域气象环境污染监测系统,提出软硬件设计方式,系统以分层、模块、网络结构的物联网,通过以HMP45D传感器为基础的污染信息采集系统及以S3C2410处理器为基础的信息处理系统组成,各系统可单独运作,且系统设计MMA7260传感节点加速器加入到节点中,克服跨区域导致的湿度传感器误差,设计防治信号冲突软件,确保系统实用性。 相似文献
186.
本文首先介绍了数据仓库的应用特点,如面向主题、集成化、数据不可更新、数据随时间的变化而变化等,然后明确提出了环境保护工程中建立数据仓库的意义,主要包括有利于强化环境保护信息化建设、有利于顺应环境保护新形势发展需求、有利于实现环保保护科学决策等,最后重点总结了环境保护工程中建立数据仓库的具体应用,主要体现在环境信息数据仓库的钻取查询、环境信息数据仓库评价和预测处理、互联网信息平台技术联机管理系统等,实现数据仓库的顺利构建,将其应用价值充分发挥出来,进而给予环境保护工程强有力的实施保证。 相似文献
187.
为了探讨三维变分法(3DVAR)对成渝城市群冬季PM2.5重污染模拟的改善效果,采用3DVAR对成渝城市群2017年12月至2018年1月的空气质量数值模拟结果进行资料同化,对比评估嵌套网格空气质量预报模式(NAQPMS)原始数据与同化再分析数据的准确率,并分析成渝重污染特征。研究结果显示,3DVAR在PM2.5、PM10和NO2的同化实验中均取得较好的改善效果,成渝地区检验站点各污染物相关系数(r)的平均提升比例依次为44%、90%和332%,r改善的站点占检验站点总数的比例分别为98%、100%和82%;检验站点均方根误差(RMSE)的平均下降比例分别为15%、37%和31%,RMSE改善的站点占检验站点总数的比例为65%、98%和84%。与原始模拟结果相比,同化结果能够更准确地反映成渝地区冬季重污染期间的PM2.5和PM10空间分布特征。 相似文献
188.
Environmental information disclosure programs seek to motivate firms to reduce their environmental impact. A variety of environmental impacts are reported in these programs and often this information is aggregated into a composite environmental index (CEI) for easier communication. The challenge is to create a meaningful index that allows environmental performance to be compared over time and space without ambiguity. In this paper, we argue that it is important to develop a cardinally meaningful and standardized CEI and use a nonparametric frontier approach to constructing such an index. This approach has the advantage to handle issues associated with data irregularity and the mixed measurability of underlying variables. We apply this approach to constructing a CEI for evaluating the environmental performance of manufacturing facilities in different industrial sectors in Los Angeles based on data from the toxic release inventory. We show how the CEI can be used to improve facility-level environmental performance. A sensitivity analysis is conducted with respect to the uncertainty in data accuracy, which demonstrates the robustness of the nonparametric frontier approach in constructing meaningful environmental indices. 相似文献
189.
190.
多部门协作模式下的生态环境监测体系研究 总被引:1,自引:0,他引:1
阐述了建立多部门协作机制,构建生态环境监测大数据平台,实现生态环境监测信息集成共享的背景及意义。通过分析青海省生态环境监测工作现状及存在的问题,提出了构建多部门协作模式下生态环境监测体系的思路和建议。 相似文献