城市内涝风险分析模型系统开发与应用

为了全面客观评估城市排水管网的排水能力、预防城市内涝灾害的发生,基于EPA SWMM 与 ArcEngine,结合等流时线法与水量平衡原理,开发了城市内涝风险分析模型系统(USRAMS)。阐述了USRAMS的原理与功能,说明了利用USRAMS进行管网排水能力评估与内涝风险分析的方法,并验证了USRAMS的适用性;对沧州市进行了现状管网排水能力评估和城市内涝风险分析,以主题图的形式准确直观地表达了瓶颈管段位置以及城市内涝风险的分布情况。实例证明,USRAMS地表产汇流模块只需径流系数与汇水时间2个参数,较好地适应了中国当前情况,二维地表淹水模拟采用水量平衡原理,计算稳定、快速,其模型结果可为城市内涝防治与雨水管网系统的规划改造提供一定参考。     

基于MIKE URBAN的典型北方城区防洪排涝模拟

由于气候变化及城镇化进程加快，城市内涝问题愈加严峻. 为优化城市排水管理，有效减少内涝损失，以河北邯郸主城东区局部为研究区，计算了区域典型设计雨型，利用MIKE URBAN模型，模拟并判定了区域不同降雨情景下区域内涝分布情况，解析区域易涝点，进而模拟评估了不同管径排水管网负荷情况. 结果表明:随着重现期增加，区域检查井溢流的数量、区域最长积水时间以及最大积水深度都有所增加，区域管网超负荷面积增大；并且在10 、20 a重现期暴雨情景下，单纯扩增管径起到的径流缓解作用较少. 研究结果可为极端暴雨下区域洪涝预警部署以及城市排水系统改造提供技术支撑.      

多尺度多模型的梯级水库优化调度决策支持系统

梯级水库群优化调度因来水预报不确定性强、水库群优化变量维数高、决策评估目标多等特点,一直是学术界和工程界的研究热点.本文分析了不同时间尺度的水文预报模型与优化调度模型的基本特征与数据需求,建立了多尺度多模型的梯级水库优化调度决策支持系统.该决策支持系统将数值天气预报的有效预报期(15d)作为短期调度模块与中长期调度模块的时间分界.短期调度模块采用数值天气预报降水量和数字流域模型预测未来15d的日径流过程,使用预报结果进行短期的梯级水库优化调度;中长期调度模块采用基于自回归和遥相关的组合预报模型,预报未来1年的月径流过程,用于中长期的优化调度.本文采用面向服务的软件架构(SOA),将年、月和日尺度的预报和调度模型集成,构建决策支持系统,可以实现多时间尺度的水情滚动预报和梯级水库优化调度.本系统在黄河上游干流梯级水库群和大通河流域梯级水库进行试验应用,结果表明该系统能够快速集成分析相关水情数据,开展梯级水库优化调度演算,及时为决策者提供清晰有效的决策辅助信息.     

InfoWorks ICM排水管网模型在实际中的应用

采用InfoWorks ICM排水管网模拟软件,建立排水管网模型,通过对内涝风险的模拟,对现有排水设施进行内涝风险评估,综合分析排水系统排水能力及抵御内涝风险的能力.     

对城市排水系统存在的问题及改造的探讨

城市排水系统是城市基础设施建设的重要组成部分,主要由排水管网和污水处理厂组成。但是由于技术、经济等方面的原因,排水系统的建设普遍存在着一定的问题,不仅严重影响着城市的正常生活与生产,严重时还会造成极大的经济损失,因此,研究城市排水管网系统存在的问题,积极采取有效措施,降低城市内涝发生的机率,对于保障城市可持续发展具有重要意义。     

基于多水源供水系统的计算机优化调度

基于多水源供水SCADA(Supcrvision Control And Data Acquisition)系统,通过建立水量预测模型、管网状态模型和水泵耗电模型,实现了给水调度由人工经验向计算机优化调度.经过对优化调度的结果分析证明:在保证供水水量和水压的情况下,计算机优化调度能节约能耗,降低供水成本.经实践,经济效益十分明显.     

SWMM在雨水排水系统规划设计中的应用

对城市排水系统进行系统的模拟计算,可以为城市排水系统规划方案的调整与优化提供理论指导.以合肥市滨湖区塘西河雨水排水系统规划为例,讨论了美国环保局开发的暴雨径流管理模型(SWMM)的应用情况,主要选取超载节点和管道的模拟结果进行管网分析,找出城市排水管网系统的“瓶颈”,以此为基础进行雨水排水系统规划方案的调整,达到缓解城市积水的目的.研究中使用的方法具有一定的通用性,可以为实际的城市雨水排水系统规划设计提供依据.     

合肥市局部区域雨水管网风险分析

对雨水管网进行风险分析,可以为减少城市内涝风险提供科学的决策依据.文章介绍了风险分析的理论和方法,根据管网运行特点和模型模拟所能提供的技术支持,确定以节点超载功能系数和节点超载时间为风险指标.以合肥市某区域雨水排水系统规划为例,采用模糊综合评价法进行雨水管网运行风险半定量研究,演示了雨水管网运行风险评价的全过程.研究中使用的方法具有一定的通用性,有利于寻找切实有效的方法全面提高城市排水系统的安全性能.     

城市内涝预警系统研究——以开封市“7·20”特大暴雨应用效果为例

基于城市基础信息资料精细化程度和模型模拟不精准影响风险预报效果的问题，提出将多元时间序列ARIMAX模型应用于积水监测站的内涝预报，以便更精准地预测积水深度及变化过程；用多普勒雷达降水临近预报和数值模式降水预报产品，驱动积涝预报模型，建立城市内涝风险预警系统.结果表明，该系统在河南开封“7·20”特大暴雨临近时段（0～2 h）内涝风险预报效果较好，短时段（3～12 h）仍有较高的参考价值，能够为城市防汛和应急提供较好的技术支撑.     

苏州河沿岸合流制系统雨天溢流频率及其启示

合流系统雨天溢流污染问题在全世界受到广泛关注．上海市苏州河沿岸合流系统在截流倍数仅1．5～3倍的情况下,溢流频率明显低于设计预期与国外的报道．为此,借助排水系统水力模型对上海市典型合流制排水系统进行分析．结果表明：上海市排水系统相互连通,管道坡度平坦,管网存储能力大,加上大面积流域的降雨时空分布差异性,赋予了合流系统巨大的调节能力,导致实际年溢流次数少于设计估算值及类似条件下日本合流系统的相应值．上海市合流系统的溢流污染负荷并不比分流制系统溢流污染负荷大,在控制雨天面源污染上具有更大优势．研究结果可为今后同类地区排水体制的选择提供参考．     

An Index mechanism for multi-scale view in spatial databases

There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3～4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰～ -7.8‰, PDB) and matrix dolomites (-6.6‰～ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084～0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078～0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.     

A computer generator for randomly layered structures

AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…     

Perspherical Approaches for Electrons in Atoms and Charged Excitons in Quantum Wells

Instead of following Fock’s expansion,we solve the Schrodinger equation for some quantum mechanical manybody systems such as electrons in atoms and charged excitons in quantum wells in a similar way in hyperspherical coordinates by expanding the wave functions into orthonormal complete basis sets of the hyperspherical hannonics(HHs)of hyperangles and generalized Laguerre polynomials(GLPs)of the hyperradius.This leads the equation to     

Advances in broadband wireless communications under high-mobility scenarios

Future mobile communication systems aim at providing very high data transmission rates, even in high-mobility scenarios such as high-speed wheel-track trains, maglev trains, highway vehicles, airplanes, guided missiles or spacecraft. A particularly important commercial application is the strong and increasing worldwide demand for high- speed broadband wireless communications （up to 574.8 km/ h test speeds or 380 km/h commercial speeds） in railways, providing data, voice and video services for applications such as onboard entertainment services to passengers, train control, train dispatch, train sensor status handling and sur- veillance. In such high-mobility scenarios, there are a number of communication challenges, including fast hand- over, location updating, high-speed channel modeling, estimation and equalization, anti-Doppler spreading tech- niques, fast power control, and dedicated network architec- ture. Because signal transmission in very high-speed scenarios will inevitably experience serious deterioration, it is imperative to develop key broadband mobile communi- cation techniques for such high-speed vehicles.     

Wuhan University Journal of Natural Sciences TOTAL CONTENTS

<正>~~     

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。     

Scale-based spatial data model for GIS

Being the primary media of geographical information and the elementary objects manipulated, almost all of maps adopt the layer-based model to represent geographic information in the existent GIS. However, it is difficult to extend the map represented in layer-based model. Furthermore, in Web-Based GIS, It is slow to transmit the spatial data for map viewing. In this paper, for solving the questions above, we have proposed a new method for representing the spatial data. That is scale-based model. In this model we represent maps in three levels: scale-view, block, and spatial object, and organize the maps in a set of map layers, named Scale-View, which associates some given scales.Lastly, a prototype Web-Based GIS using the proposed spatial data representation is described briefly.     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to