地下水库调蓄能力综合评价的指标体系与模糊集方法   总被引：2，自引：0，他引：2       下载免费PDF全文

郑德凤  王本德  年廷凯 《水科学进展》2005,16(5):720-725

从维护生态平衡与水资源可持续开发利用的角度定义了地下水库的调蓄能力,提出地下水库调蓄能力综合评价的指标体系。并在模糊模式识别理论与模型的基础上,去除指标间的相关性,建立一种适合于对多指标体系的地下水库调蓄能力进行综合评价的多层模糊模式识别交叉迭代模型。实例应用表明,该模型具有能同时考虑定性与定量指标,又能将迭代结果与决策者经验知识相结合来确定多指标权重的优点,便于推广应用。  相似文献   

公路和城市街渠机动车大气污染物扩散模式发展综述   总被引：2，自引：0，他引：2  

彭军  张明  王体健 《南京气象学院学报》2005,28(3):423-432

随着城市机动车数量的增加，机动车尾气污染已经成为城市污染物的重要来源。研究机动车尾气扩散规律，可为公路建设，车流量控制，街道大气污染的监测、评价与防治提供科学依据。对公路机动车污染物扩散模型的发展进行了回顾，详细论述了高斯模式、数值模式、统计模式等模式的发展历程及其目前存在的问题，并比较了几种典型模式的性能优劣及其各种条件下的适用性。随后对城市街渠峡谷机动车污染物扩散模型进行专述，指出了街渠峡谷模式研究的难点在于街渠流场模拟，介绍了国外最新街渠流场研究方法。最后提出了当前机动车大气污染物扩散模型存在的主要困难，展望了其解决途径和发展的方向。  相似文献   

合肥市夏季热岛特征研究   总被引：8，自引：1，他引：8  

石春娥王兴荣  吴必文何彬芳吴息  陈万隆 《南京气象学院学报》2005,28(5):672-678

根据2002牟夏季高温期间合肥市城市小气候考察的资料，分析了合肥市夏季城市热岛特征以及热岛强度的历史变化。结果表明：1）合肥市夏季热岛强度的日变化与冬季明显不同，夏季晴天一天中热岛强度只出现一个峰值，其基本特征与Oke提出的理想状态下的城市热岛强度日变化的模式曲线非常相似，而冬季与高纬地区的加拿大卡尔加里城市的热岛强度日变化特征接近。这反映了冬、夏两季人类活动、能源消耗量的不同；2）随着城市范围的扩大和城市绿化工程的实施，合肥市热岛面积、分布形状有了一定的改变，但主要分布特征和强度基本没有变化。  相似文献   

城市热岛效应监测方法研究进展   总被引：16，自引：0，他引：16  

肖荣波  欧阳志云  张兆明  王效科  李伟峰  郑华 《气象》2005,31(11):3-6

城市热岛效应是一种由于城市建筑及人们活动导致的热量在城区空间范围内聚集的现象,是城市气候最明显的特征之一.由于城市热岛影响因素以及相互关系的复杂性,为了精确细致地描述其时空分布,人们采用了多种方法来研究城市热岛现象,主要归纳为：气象站法、定点观测法、运动样带法、遥感测定法以及模拟预测等.最后,认为各种测定方法都存在一定的缺陷,建议多种测定方法综合运用.  相似文献   

地下导线随盾构推进逐段接测中的可靠性检验     

高俊强  潘庆林 《现代测绘》2005,28(1):17-19

盾构法施工的要点是需要在井下布设高精度的控制支导线，当我们根据盾构推进进度对导线接测时，由于观测条件、观测方法、观测仪器基本相同，但观测、的成果往往会存在一定的差异，有时我们无法直接判断成果的正确与否，此时，采用测量平差中的统计检验的方法来分析这些观测数据，可以取得比较满意的结果。  相似文献   

可控深度电法对水平柱体和垂直界面的计算和实验     

包本刚  黄志平 《地质与勘探》2002,38(2):71-74

球状地球体可控深度电法的效应系数可近似地全面表达可控深度电法和各种效应。通过点源二度体的电算模拟实验，证明了该方法在水平柱状体和地下存在电阻率垂直界面的条件下，也是有效的。  相似文献   

Ground‐shaking mapping for a scenario earthquake considering effects of geological conditions: a case study for the 1995 Hyogo‐ken Nanbu,Japan earthquake     

Kazuo Fujimoto  Saburoh Midorikawa 《地震工程与结构动力学》2002,31(12):2103-2120

In order to examine the applicability of ground‐shaking mapping techniques to a near‐field earthquake, a peak ground velocity map of the 1995 Hyogo‐ken Nanbu, Japan earthquake computed from seismic zoning methods that consider the effects of geological conditions is compared with the actual observed intensity map. When computing the ground‐shaking map, the site amplification at each site is calculated in terms of the average shear‐wave velocity of the ground estimated from the corresponding geomorphological conditions. This map shows a relatively good agreement with the observed intensity map. However, the computations provide smaller values for certain disastrous areas of the earthquake, where the effects on ground motion of a deep, irregular underground structure have been reported. The effect of such structures on site response is examined implementing 2D FEM analyses, thereby being also incorporated into the method. Results considering the effect of the irregular underground structure show better agreement with the observed intensity map. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

MAPGIS管网开发平台的设计   总被引：3，自引：1，他引：3  

曾文  张德津 《地球科学》2002,27(3):250-254

设计了一个通用的管线信息系统开发平台。该开发平台构筑于大型GIS基础软件MAPGIS之上，具有完备的数据模型，强大的数据包容能力。采用多层次体系结构，包含网络数据管理与网络分析、管网工作区管理、专业管网工作区管理、管网工程管理、管网实用服务工具包、管网管理类库和控件库等多个模块。该开发平台同时支持API和组件接口，二次开发便利灵活，可以较好地满足管网应用系统的。在该平台基础上已开发出多个成功的管网信息系统，证明它具有广泛的应用前景。  相似文献   

The fall and rise of metropolitan government in Copenhagen     

Hans Thor Andersen  Frank Hansen  John Jørgensen 《GeoJournal》2002,58(1):43-52

In this paper it is argued that the re-establishment of a metropolitan government in the Greater Copenhagen Area in 2000 (Greater Copenhagen Authority) is not to be seen as a return to the kind of regional, coordinative authority (Greater Copenhagen Council) that was abolished in the Thatcherite climate of the 1980s. Throughout the 1980s and 1990s new forms of urban governance, entrepreneurialism and a higher national priority to the capital region were introduced, which changed the conditions under which the new metropolitan government is operating. This `contextualization' of the analysis of the two generations of metropolitan government points to the fact that typologies of metropolitan government, such as the one put forward by Sharpe (1995), often lacks analytical cogency. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Milan: The city of constant renewal     

Anna Trono  Maria Chiara Zerbi 《GeoJournal》2002,58(1):65-72

Traditional models of urban development are no longer adequate to describe current metropolitan transformations. These are now at the centre of a debate concerning management and administration. In Italy, delays in resolving problems of urban and metropolitan government, despite the legal framework provided by Law 142/90, have weighed heavily on the larger urban areas of the country: Rome, Naples, Milan, which have not been able to tackle the issue of metropolitan government. Recent legislation, while not providing a pre-defined institutional solution, allows separate administrative districts to collectively establish metropolitan institutions of `variable geometry'. The Milan urban area is not one city, but a system of mutually-dependent cities, linked to each other and the rest of the world by a transport network still requiring much investment. The vitality of its economic structure (especially its small firms) is held back by seriously inadequate infrastructure and low external economic efficiency. The provincial capital may boast `historic centrality' but the most interesting potential for development is to be found on the periphery and in the administrative districts immediately surrounding it, in the recovery of derelict industrial areas and dormitory towns established in the 1950s and 1960s, especially to the north. Recovery of derelict areas, green areas, and better transport links within the urban area and with the outside world are the key elements in the reorganization of `Greater Milan'. In this situation of rapid transformation the most appropriate political strategies involve negotiated planning. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献