城市突发事件中基于事故演变的救援需求决策模型及其优化求解

针对城市突发事件中待救点对应急救援物资的需求状态随着事故的演变而发生变化的情况,将待救点对应急救援物质的需求设计成马尔可夫决策过程,并提出一种动态的物资调配策略,构建救援物资需求决策模型,然后通过花朵授粉算法进行优化求解。某市突发地震应急物资调配实例证明,本文方法能够给出合理的救援需求满足策略,使得待救点对物资的需求更低,需求变化更加平稳。花朵授粉算法对模型求解的效果相比粒子群算法和萤火虫算法有更快的收敛速度和更优的求解结果。     

基于Leslie种群模型的城市流浪猫数量模型研究

城市中日益增多的流浪猫正在成为一个人们关注的问题.其种群个体数量有不同的模型可用于描述,这里应用Leslie种群模型建立了城市雌性流浪猫数量模型,并在此基础上推导了整体数量模型;分析了随时间发展流浪猫数量的性态.根据有关资料数据,给出模型算例,预测了发展趋势.     

中原城市群竞争力评价研究

在构建的城市群竞争力评价指标体系的基础上,采用SPSS15.0统计分析软件,运用主成分分析法对中原城市群的竞争力进行研究,分析了中原城市群竞争力的现状、优势及其存在的问题,并提出了具体的解决问题的对策措施.     

FIVE ISLANDS EFFECTS OF SHANGHAI URBAN CLIMATE

By combining the anthropogenic condition (the change of urban surface nature, the emission of anthropogenic heat and pollutant) and the weather condition (the large-scale air circulation and local weather situation), the author clarified the formative processes, features and relationship of the five islands (heat island, dry island, moisture island, rain island and turbidity island) effects of Shanghai urban climate. This research is not only important to the theoretical problem of how the man's activities influence the climate, but also provides scientific basis for urban weather prediction, urban air pollution protection and urban design.     

一种包含递归的核回归估计的回归预测模型

本文首先构造了包含递归的核回归的回归模型 ,然后将其应用于湖南省城镇居民消费性支出 ,提高了拟合度 ,减少了预测误差     

新疆城市经济区划分研究

运用因子分析法对新疆１９个市及６８个城关进行了综合实力指数评价及等级层次划分,在此基础上,以７条国道为主,６９条省道为辅,模拟城市之间的经济联系网络,计算出中心城市外部效应场划分指数,得出新疆各中心城市的经济影响区范围,最后根据经济影响区界限,参照现实情况及发展动态,将新疆划分为七个城市经济区。     

A Fractional Factorial Design Applied to the Optimization of Microwave- and Ultrasound-Assisted Acid Leaching Methods for Heavy Metals Determination in Sludges by Flame Atomic Absorption Spectrometry

Abstract

The sampling performance of C₁₈ cartridges coated with DNPH has been studied for twenty four C₁-C₉ carbonyls in experiments involving sampling of parts per billion levels of carbonyls in urban air. indoor air and laboratory experiments. The cartridge background carbonyl content in thirty six batches of cartridges averaged 85, 137 and 155 nanogram/cartridge for formaldehyde, acetaldehyde and acetone, respectively, and was below analytical detection for all other carbonyls. Carbonyl-DNPH derivative recovery from the cartridge was complete in the first elution with 2 mL acetonitrile, and this for twenty four carbonyls at concentrations of 0.02–73 μg carbonyl/cartridge. Studies carried out using two cartridges in series showed no breakthrough, for the sixteen carbonyls tested, at concentrations of 0.10–49 μg carbonyl/cartridge and volumes of air sampled = 6–370 L. Average relative standard deviations (RSD) for replicate analyses were 0.20–13.2% for twenty one carbonyls. Average RSD for co-located samples were 0.9–16.2% for eighteen carbonyls. Comparison of RSD for replicates and RSD for co-located samples for thirteen carbonyls indicated that the overall method precision was limited by sampling precision rather than by analytical precision.     

Estimation of Atmospheric Dust Deposition on Plant Leaves Based on Spectral Features

Urban atmospheric dust is a significant problem and becoming a considerable pollution source in many cities. This study was based on a comparison of spectral reflectance on the surfaces of dusty and clean leaves. A significant linear relationship (r = 0.811) correlation between the dust weight and near-infrared band region (700–1000 nm) was found through analysis of the spectral data. This relationship obtained from near-infrared band regions, based on the main effects and cluster and interval analysis, was more distinct and stable than that of blue, green, red, and middle-infrared band regions. Thus, the use of near-infrared band data is a reliable method to estimate the amount of dust deposition on plant leaves. A regression model (R² = 64.3%) was constructed based on dust deposition on plant leaves and a near-infrared ratio. The model proved to be accurate as regards an estimation of dust weight, based on a comparison of residuals (normal distribution) and accuracy tests (slope = 0.8437). This model could provide a methodological basis for spatial dust distribution analysis and has the potential for evaluating air pollution levels.     

高架路匝道附近的交叉口交通流分析

考虑高架路匝道附近的交叉口交通流问题．所采用的模型是经修正的一维管流交通流模型,在运动方程中引入了弛豫项．基于该模型,对上海市内环线的武宁路匝道附近的交通流进行了案例分析,着重对主干道上的右转车辆干扰效应进行了数值模拟,所得结果与实测数据相当符合．分析表明,右转车辆对主干道的“挤压”效应是引起某些交叉口交通拥塞的重要原因,而设置在繁华路口的高架路匝道加剧了这种拥塞状况。     

Analytical Standards and Methods for the Determination of Polynuclear Aromatic Hydrocarbons in Environmental Samplest

Abstract

Standard reference materials (SRM's) have been produced, certified, and issued by the United States National Bureau of Standards (NBS) since 1905. NBS currently issues more than 1000 SRM's of various types, including nuclear materials, rubber, clinical and environmental trace metal standards. The most recent addition to this group is a series of environmental trace organic materials with certified concentrations of selected polynuclear aromatic hydrocarbons (PAH), phenols, and N-heterocyclic compounds. Until recently, trace organic SRM's were non-existent due to the lack of analytical methodology necessary for certification. Details concerning the analytical methods developed and used for certification of the concentrations of several PAH in SRM's 1580 (Organics in Shale Oil), 1644 (Generator Columns for PAH in water), 1647 (PAH in Acetonitrile), and 1649 (Urban Particulate Matter) are given along with some suggested uses for these SRM's.