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1.
吴小飞  崔金东  李旭 《甘肃科技》2013,29(8):4-5,65
建设应急避难疏散场所是国际社会应对突发事件的一项灾民安置措施,同时也是现代化大城市用于民众躲避地震、洪水、火灾、爆炸等重大自然灾害和事故的安全避难场所。唐山大地震、汶川大地震和玉树地震等灾害的灾后避难行动表明,城市必须规划建设避难疏散场所。论文调查了秦皇岛市作为主要应急避难疏散场所的公园绿地的现状,分析了秦皇岛市在应急避难疏散场所规划过程中存在的问题。  相似文献   

2.
灾后应急救助十分关键,特别是多地同时受灾情况下.为此,考虑将灾民安置与物资运输一体化规划,建立连续消耗多级应急物资调配数学模型.在此基础上,以应急系统施救成本和施救不及时损失为目标函数构建优化模型,并应用遗传算法(GA)和序列线性规划(SLP)算法相结合策略对物资调配进行优化.构造四级救灾物资调配算例模拟救灾过程.数值结果表明,使用GA全局寻优结合SLP局部寻优策略相较单一优化算法能有效找到更优解.所提出的优化策略可为灾后多级多受灾点连续消耗应急物资调度提供可行方案.  相似文献   

3.
大型公用建筑火灾时人员应急疏散评价模型研究   总被引:3,自引:0,他引:3  
应急疏散措施的优劣是评价大型公用建筑安全水平高低的重要标准之一。本文通过分析影响大型公用建筑应急疏散措施有效性的主要因素,参照相关法规及大型公用建筑应急疏散时各指标因素的层次,建立了大型公用建筑应急疏散评价模型。将该模型应用到某高校图书馆的应急疏散评价过程中,验证了模型的准确性,为建筑物火灾人员应急安全疏散提供了切实可行的参考依据。  相似文献   

4.
为了获得受灾居民到避难所总旅行成本最小的疏散路径,以天津市中心城区为例,基于替换插值机制算法,以满足城市避难所容量限制且保持避难场所空间连续性为目标,运用C#语言编写算法划分天津市中心城区公园、广场和绿地等应急避难所的服务区范围;以疏散总距离最短为目标,在不超过容量限制的条件下,确定各受灾点到达对应避难所的最佳路径,并基于SimpleMap自主开发应急疏散分析工具对路径选择进行动态模拟.结果表明:天津市中心城区共有避难所842个,避难总面积为18 802 480.87 m~2,在受灾居民疏散路径分配中有594个容量满员,248个未满员.受灾居民到达避难设施总旅行成本为3 753 036.977 km,与直接插入算法相比,替换插值算法所得结果节约旅行成本59.06%.研究结果为建设城市安全系统、制定灾后应急疏散策略提供了一定的科学参考.  相似文献   

5.
城市应急避难场所责任区划分对提高灾民疏散效率和保障灾民生命安全具有重要意义。该文综合考虑路网可达性、避难场所建设成本和承载容量等多因素,耦合地理信息系统(GIS)位置分配中的最小化设施点模型和最大化有容量限制的覆盖范围模型,构建城市应急避难场所选址和责任区划分方案,并以昆明市中心区域为例进行实证分析与模型验证。结果表明:研究区域的应急避难场所数量存在最优值,根据政府建设成本最小及避难需求分配区域利用率最高,确立了研究区域最佳应急避难场所为9个;政府需要对篆塘公园进行容量扩建,并将五华广场和胜利广场一同启用,才能使整个研究区域的避难服务效果达到最佳;其对应的避难场所责任区可划定为8个。该研究结果可对城市突发事件应急决策和救援提供支持。  相似文献   

6.
多出口室内行人出口选择行为研究   总被引:2,自引:2,他引:0  
刘泽高  陈栋  薛郁 《广西科学》2015,22(4):388-394
【目的】研究行人流在不同设定条件下选择合理出口的行为,为多出口室内行人疏散提供参考。【方法】采用元胞自动机模型,在静态场的基础上,模拟行人流在多出口室内的出口选择行为。在模型中引入出口代价,即行人选择目标出口时需要考虑的距离及其与他人竞争因素的加权平均(权重为k)。为实现出口选择机制,赋予每个出口元胞1个单元场,当行人评估出室内最小代价值的出口时,选用该出口的单元场来进行迁移。【结果】当权重k合适(区间较大)时,在初始行人分布均匀或不均匀、出口分布对称或不对称,以及在疏散过程中增加应急出口的情况下,行人都会充分利用空闲的出口,使不同的出口都聚集大致相等的人数;而且应急出口打开时间越早行人流疏散的效果越好,应急出口打开过晚时行人疏散的效果甚至会比没有应急出口的情况还差。【结论】出口代价的引入,使模型能合理地描述多出口的室内行人疏散。  相似文献   

7.
在分析现有城市应急物资分配模型的基础上,构建了一个多出救点、多受灾点、多种应急物资分配的决策模型。该模型以受灾点的系统损失最小为目标,充分考虑灾害严重程度、应急物资的重要性、受灾点对应急物资的需求紧迫程度等因素,在不完全扑灭情况下确保受灾点物资分配的公平性。最后从理论上分析最优性条件,通过算例验证了模型的有效性。  相似文献   

8.
魏诗雨  刘勇 《科学技术与工程》2020,20(33):13942-13948
为改善现有飞机火灾应急疏散研究滑梯处旅客行为分析较少及疏散方案整体性不足等情况,规划出包括舱内狭小空间、应急滑梯以及地面在内的一体化疏散通道。此外引入惶恐系数和集体关系因素对传统社会力模型进行改进,根据问卷调查充分了解人群在机上危险时刻的心理状态从而设置建模参数。用AnyLogic软件对一体化疏散流程进行模拟,分析仿真过程中拥挤点的产生原因及环境影响因素并提出合理方案,从不同风向下应急出口开放数量及人员分拣区位置设置等方面进行优化。所得研究结果完善了机上旅客疏散流程,有利于机场应急预案改进及演练。  相似文献   

9.
基于应急条件下乘客可能采取的最近疏散行为、退避疏散行为、从众疏散行为、回返疏散行为、均衡疏散行为等5种主要疏散行为对乘客吸引力的动态变化,构建了基于应急信息刺激的乘客疏散行为动态切换的3层模型体系.对不同微观行人仿真模型的优缺点进行分析,构建了融合应急行为决策模型、A*算法、社会力模型的应急疏散联合仿真体系.最后,利用实际城市轨道交通车站的应急疏散调查数据,对模型参数进行了标定,并对仿真效果进行了验证.  相似文献   

10.
针对目前国内外突发灾害事件频发、应急交通组织保障能力不足等问题,在充分考虑突发灾害对道路交通网络、交通出行行为影响的基础上,基于动态交通分配理论,结合突发灾害下的出行者疏散路线选择行为,构建了受灾区域应急疏散路线的交通信号优化控制模型,并采用并行蚁群算法对该模型进行优化求解,以提高求解速度和全局收敛能力.最后搭建了集群计算平台对该模型和算法进行模拟测试,结果表明,采用并行蚁群算法对模型进行优化求解,可以获得较好的时间性能和优化效率,满足应急交通保障系统在线决策支持的要求.  相似文献   

11.
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.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
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。  相似文献   

14.
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  相似文献   

15.
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  相似文献   

16.
17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
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.  相似文献   

20.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

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