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城市安全问题伴随着城市的产生而出现,近年来随着城市化进程在全球范围迅猛推进,城市安全问题显得尤为重要与紧迫。资本、人口向城市大量集聚,城市物质空间结构和城市社会结构巨变,城市整体建成环境及其依托的自然生态环境恶化趋势明显,城市安全脆弱度增大,当代城市安全面临新的挑战。西方发达国家对当代城市安全问题的新动向极为关注,对城市安全观念作了深入全面的拓展研究。从城市安全动态发展的视角,对相关文献进行梳理与总结,考察当代西方城市安全观念研究变迁态势,以期为我国城市安全问题的研究深化提供有益的借鉴和启示,推动我国城市化进程的健康和可持续发展。 相似文献
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费陈;赵亮;贺拥亮;李银城;徐嵩 《现代防御技术》2025,53(1):1-10
针对复杂城市环境下无人机目标打击问题;引入一种基于电鳗觅食优化算法的无人机目标打击方法。该方法首先设置稀疏环境无敌防守和密集环境有敌防守2种场景并设计相应的约束条件和航迹优化代价函数以符合城市环境飞行需求;然后通过电鳗觅食优化算法(electric eel foraging optimization;EEFO)为无人机规划出一条合理的目标打击轨迹;最后得到其飞行轨迹和适应度值;并与SO;SCA;WOA;MFO;HHO 5种算法进行对比。实验结果表明;在稀疏环境无敌防守场景下EEFO算法比其他五种算法具有更高的轨迹规划效率和稳定性;消耗的航迹代价最小且收敛更快;在密集环境有敌防守场景下EEFO算法与其他5种算法相比;所规划出的目标打击轨迹最优且消耗的航迹代价收敛趋势更好;任务完成度最高;具有更好的表现。 相似文献
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传统的城市环境理念主要是针对城市在发展过程中的污染问题,即解决城市“三废”造成的环境问题。本文以自然生态原则为依据,从生态学的角度研究建筑设计的准则、设计的道德基础和技术经济的合理性,探讨人、建筑、自然三位和谐一体,构建可持续的人类居住环境. 相似文献
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何翊 《中国人民武装警察部队学院学报》2007,23(12):59-63
工业社会的城市灾害突出的表现为各式各样的环境公害,城市环境恶化日益引起人们的普遍关注。城市是一个国家和地区政治、经济、文化的中心,又是人口、财富、信息的聚散地,正是现代化城市的这种特征造成了一旦发生灾害就会导致灾难。城市灾害的防治和减灾事关一个城市的存亡。传统的城市灾害的特点表现为人员伤亡惨重、经济损失巨大、社会影响广泛等。进入21世纪,随着城市化进程的加快,城市灾害表现出了许多新的形式。例证了几种城市灾害,并分析了导致这些城市灾害的各种原因,寻求解决城市灾害的有效途径。 相似文献
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Andrea Beccaro 《Small Wars & Insurgencies》2018,29(2):207-228
ISIS (the Islamic State of Iraq and Syria) has become a key political and military actor in the Middle East and in North Africa. This essay aims at outlining ISIS warfare through an analysis of its operations in the frame of hybrid warfare theory proposed by Frank Hoffman. Therefore, the paper deals with: the role of terrorist tactics in ISIS warfare and the relationship between terrorism and insurgency; ISIS use of technology, mainly with regard to suicide attacks and to drones; and the relevance of urban warfare. Finally, the paper highlights how ISIS operates and the most threatening features of its warfare. 相似文献
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Despite problems of violence domestically, Brazil has played a key leadership role as part of MINUSTAH peacekeeping operations in Haiti since 2004. This article addresses how Brazil's international military engagement is shaping domestic approaches to urban security, and what may be the implications of the use of military strategies, operations, and norms to address issues of public security in Brazilian cities. It is argued that current approaches toward urban security employing military-trained peacekeepers actually represent a continuation of old paradigms, yet these recent militarised approaches are likely evolving into newer and potentially more accountable forms by constraining indiscriminate use of force and establishing a positive state presence in marginal urban areas. As such, the article connects long-established issues of dealing with urban violence in Latin America with ongoing debates in the United States and beyond about post-counterinsurgency approaches to increasingly urban conflict settings. It reflects on potential lessons to be learned from the Latin American perspective, while showing also how these have changed over the last decade. The article concludes that despite the potential utility of force in some urban conflict settings, this approach could entail a normative shift towards legitimising forceful containment of violence, and hinder democratic consolidation in Brazil. 相似文献
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杨欣 《中国人民武装警察部队学院学报》2014,(8):46-48
通过对城市交通隧道火灾形势、原因及危害性的分析,指出现行《建筑设计防火规范》对城市交通隧道消防设计指导存在不详之处,应进一步明确避难设施、自动灭火系统及火灾自动报警系统等方面的设计要求,由此提出了通过进一步修订现有"处方式"规范,结合性能化消防设计,科学合理解决城市交通隧道面临的防火问题的有效方案。 相似文献
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In the literature two common macroscopic evacuation planning approaches exist: The dynamic network flow approach and the Cell–Transmission–Based approach. Both approaches have advantages and disadvantages. Many efficient solution approaches for the dynamic network flow approach exist so that realistic problem instances can be considered. However, the consideration of (more) realistic aspects (eg, density dependent travel times) results in non‐linear model formulations. The Cell‐Transmission‐Based approach on the other hand considers realistic traffic phenomena like shock waves and traffic congestion, but this approach leads to long computational times for realistic problem instances. In this article, we combine the advantages of both approaches: We consider a Cell‐Transmission‐Based Evacuation Planning Model (CTEPM) and present a network flow formulation that is equivalent to the cell‐based model. Thus, the computational costs of the CTEPM are enormously reduced due to the reformulation and the detailed representation of the traffic flow dynamics is maintained. We investigate the impacts of various evacuation scenario parameters on the evacuation performance and on the computational times in a computational study including 90 realistic instances. 相似文献