可计算一般均衡(CGE)模型与环境政策分析

CGE模型是进行环境政策分析的理想工具，实际上CGE模型也是唯一胡可能精确评估环境政策社会成本的分析手段。本文介绍了在环境政策分析中应用CGE模型的基本思路和不同类型；回顾了CGE模型在环境政策分析中的应用领域及国内应用现状；指出今后的环境政策分析中应用的CGE模型应该更多地结合经济体的现实特征，其发展方向则体现在三个方面；在分析环境政策社会成本的同时也考虑这些政策的社会效益、分析环境政策的分配效应、加强区域CGE模型在环境政策分析中的应用。     

Comparison between the Chinese EIA Guidelines for Air Dispersion Modelling and the Advanced Air Dispersion Model ADMS

1 INTRODUCTION According to the Environmental Protection Law of P.R. China, and the Environmental Protection Management Method on Construction Projects the Technical Guidelines for Environmental Impact Assessment (EIA) (HJ/T 2.1~2. 3-93) have defined how environmental impact assessment should be carried out for construction projects, in terms of the general principle, methodology, contents and requirements. Technical Guidelines for Environmental Impact Assessment on the Atmosphe…     

马尔柯夫预测模型在环境预测中的应用

马尔柯夫预测模型利用系统的现在状态和发展方向去预测系统将来可能状态的概率。它在选择污染治理策略，环境状态变化的可能方向及发展趋势预测等方面地产可应用，其预测结果为某事件实现的概率即可能程度。     

基于修正场模型的区域空间结构演变及空间整合〖HT2”SS〗——以泛长江三角洲为例

随着长江三角洲经济发展及其面临问题,长三角泛化已成为必然,研究泛长三角空间结构演变有利于正确认识和把握其空间发展态势,从而为泛长三角区域一体化进程提供问题依据。以场强模型为基石,根据扩散理论,构建了场对数扩散效应模型,从城市场这一新视角分析了泛长三角区域空间演进过程。泛长三角城市影响区自改革开放以来经历了疏点-“之”-“几”-“皮皮虾”-“鳊鱼”5种空间形态;根据这一空间形态极其演变规律提炼出疏点类型、散块类型、条带类型、团块类型、板块类型五种空间结构类型;在此基础上,由“以点建轴,以轴布面”思想,以产业结构整体升级为引导,对泛长三角区域进行空间整合,形成由三级中心城市、三级发展轴线以及内核城市群、邻接城市群和外缘城市群组成的核心-边缘结构三级产业城市群。     

北京冬季雾霾频发期VOCs源解析及健康风险评价

采用低温固体吸附采样、热脱附-气相色谱-质谱联用的方法对北京冬季雾霾频发期空气中挥发性有机物(VOCs)进行了连续监测,对以雾霾期为标志划分的4个阶段的VOCs浓度水平与组成变化特征进行了分析研究,利用正矩阵因数分解模型(positive matrix factorization,PMF)对VOCs的可能来源进行解析,并进行了健康风险评价.结果表明,VOCs的日均浓度为332.34μg·m~(-3),苯系物和卤代烃在研究区域大气环境的VOCs中含量占主导地位;冬季雾霾的主要污染物排放源为溶剂/涂料使用及机动车尾气排放;区域所检出的致癌性VOCs的致癌风险均超过了EPA给出的风险限值.     

循环经济发展评价的生态效率测算模型及应用

生态效率是基于可持续发展的思想,鉴于循环经济发展和实际环境的需求,通过构建循环经济发展评价的生态效率测算模型,针对循环经济中资源和环境2个重要方面,选择实例进行模型的应用。所选择研究对象经过测算,生态效率在"十一五"期间呈现波动上升,在5年时间增长了1.1倍,但仍处于末端治理为主的循环经济发展阶段,较为客观地反映了当地循环经济的发展轨迹。通过相关分析和说明,为循环经济发展评价提供生态效率分析这一方案选择。     

Performance of CH4MOD wetland for the case study of different regions of natural Chinese wetland

Reliable national estimates of CH₄ emissions from natural wetlands depend on model validation based on site observations. We therefore evaluated the performance of the CH4MOD_wetland model in simulating CH₄ emissions from 11 representative wetland sites in five regions of China. Model performance analysis showed that this method effectively simulates differences in the CH₄ fluxes between different sites and regions. The model efficiency for estimating the daily CH₄ fluxes in the northeastern China (NE), Inner Mongolia and northwestern China (NW), the North China plain and the Middle-Lower Yangtze Plain (E) and the Qinghai Tibetan Plateau (SW) was 0.51, 0.20, 0.52 and 0.65, respectively. The efficiency for estimating the annual mean CH₄ fluxes in southern China (S) was 0.99. Systematic negative deviation between the simulated and observed CH₄ emissions existed in all regions, especially in the NW region, which had a mean deviation (RMD) value of − 36.7%. On the national scale, the root mean square error (RMSE), the RMD, the model efficiency (EF) between the simulated and observed seasonal values were 28.7%, − 7.8% and 0.93, respectively. The CH₄ emissions showed the highest sensitivity to air temperature in the NE and SW regions, and to water table depth in the E region. Based on the sensitivity analysis, future climate warming and wetting are likely to increase the wetland CH₄ emissions at different levels in all regions of China.     

The separation of reinforced cementitious composites with a stream-line cutting tool

The paper provides a model for the cutting of reinforced concrete members with stream-line cutting tools. The model is an extended version of the energy model originally developed by Momber and Kovacevic (1995) for hydro-abrasive machining. The model allows the stepwise calculation of the energy absorbed during the cutting of the two parts of the compound - steel bar and matrix material. Hydro-abrasive cutting tests on different cementitious composites are performed in order to verify the numerical results. It is shown that the cutting process can be subdivided into four cutting stages whose locations depended on the energy locally available at the erosion site.     

Methodology for Developing Flood Rule Curves Conditioned on El Niño‐Southern Oscillation Classification1

Lee, Se‐Yeun, Alan F. Hamlet, Carolyn J. Fitzgerald, and Stephen J. Burges, 2011. Methodology for Developing Flood Rule Curves Conditioned on El Niño‐Southern Oscillation Classification. Journal of the American Water Resources Association (JAWRA) 47(1):81‐92. DOI: 10.1111/j.1752‐1688.2010.00490.x Abstract: Regional climate varies on interannual and decadal time scales that in turn affect annual streamflows, flood risks, and reservoir storage deficits in mid‐summer. However, these variable elements of the climate system are generally not included in water resources operating policies that attempt to preserve a balance between flood risk and other water resources system objectives. A methodology for incorporating El Niño‐Southern Oscillation (ENSO) information in designing flood control curves is investigated. An optimization‐simulation procedure is used to develop a set of ENSO‐conditioned flood control rule curves that relate streamflow forecasts to flood control evacuation requirements. ENSO‐conditioned simulated flood risk and storage deficits under current operating policy are used to calibrate a unique objective function for each ENSO classification. Using a case study for the Columbia River Basin, we demonstrate that ENSO‐conditioned flood control curves constructed using the optimization‐simulation procedure consistently reduce storage deficits at a number of interrelated projects without increasing flood risk. For the Columbia Basin, the overall improvements in reservoir operations are relatively modest, and (in isolation) might not motivate a restructuring of flood control operations. However, the technique is widely applicable to a wide range of water resources systems and/or different climate indices.