Investigation of effects of hazard geometry and mitigation strategies on community resilience under tornado hazards using an Agent-based modeling approach

A large number of communities are impacted annually by the increasing frequency of tornado hazards resulting in damage to the infrastructure as well as disruption of community functions.The effect of the hazard geometry(center and angle of tornado path as well as the tornado width)is studied herein on how it influences the recovery of physical and social systems within the community.Given that pre-disaster preparedness including mitigation strategies(e.g.,retrofits)and policies(e.g.,insurance)is crucial for increasing the resilience of the community and facilitating a faster recovery process,in this study,the impact of various mitigation strategies and policies on the recovery trajectory and resilience of a typical US community subjected to a tornado is investigated considering different sources of uncertainties.The virtual testbed of Centerville is selected in this paper and is modeled by adopting the Agent-based modeling(ABM)approach which is a powerful tool for conducting community resilience analysis that simulates the behavior of different types of agents and their interactions to capture their interdependencies.The results are presented in the form of recovery time series as well as calculated resilience indices for various community systems(lifeline networks,schools,healthcare,businesses,and households).The results of this study can help deepen our understanding of how to efficiently expedite the recovery process of a community.

Agent-Based Network Modeling Study of Immune Responses in Progression of Ulcerative Colitis

Ulcerative colitis, an inflammatory bowel disease, is a chronic inflammatory disorder that results in ulcers of the colon and rectum without known etiology. Ulcerative colitis causes a huge public health care burden particularly in developed countries. Many studies suggest that ulcerative colitis results from an abnormal immune response against components of cornrnensal rnicrobiota in genetically susceptible individuals. However, understanding of the disease mechanisms at cellular and molecular levels remains largely elusive. In this paper, a network model is developed based on our previous study and computer simulations are perforrned using an agent-based network modeling to elucidate the dynamics of immune response in ulcerative colitis progression. Our modeling study identifies several important positive feedback loops as a driving force for ulcerative colitis initiation and progression. The results demonstrate that although immune response in ulcerative colitis patients is dominated by anti-inflarnrnatory/regulatory cells such as alternatively activated rnacrophages and type II natural killer T cells, proinflarnrnatory cells including classically activated rnacrophages, T helper 1 and T helper 17 cells, and their secreted cytokines tumor necrosis factor-α, interleukin-12, interleukin-23, interleukin-17 and interferon-γ remain at certain levels （lower than those in Crohn＇s disease, another inflammatory bowel disease）. Long-terrn exposure to these proinflarnrnatory components, causes rnucosal tissue damage persistently, leading to ulcerative colitis. Our simulation results are qualitatively in agreement with clinical and laboratory measurements, offering novel insight into the disease mechanisms.

基于OPM与ABMS的体系架构驱动仿真方法

建模与仿真在武器装备体系研制的全过程中都发挥着非常重要的作用,但是对于如何从体系架构中提取仿真所需的数据从而驱动构造仿真系统运行的研究还比较少,无法发挥架构驱动仿真的优势。采用OPM(ObjectProcess Methodology)对武器装备体系架构进行描述,通过一定的方法从体系架构中提取ABMS(Agent Based Modeling and Simulation)仿真所需的数据,从而支持仿真的运行,继而实现利用ABMS分析武器装备体系架构并对武器装备体系的能力进行评估。

建筑施工安全绩效与安全投入关系的ABM模拟

为探索安全投入方案优化方法,在Netlogo软件环境下,构建代理模型(ABM),基于津浙2省市建筑工程项目实地调研数据,采用蒙特卡罗方法对ABM模型进行重复仿真模拟,完成安全投入指标敏感性排序,探讨安全投入与安全绩效变化趋势。研究表明:安全投入增加能有效提升大多数安全绩效,但边际递减效应明显,其中,安全预防费用对安全绩效的影响能力最强,且与安全工程费用和安全员薪酬间存在明显的协同效应;安全工程费用的作用,受限于事故死亡人数这一安全绩效指标,存在佩尔兹曼效应;就总投入而言,存在经济最优值。

基于ABM仿真的实时市场结算不平衡费用分析

随着中国电力市场改革进程的深化,首批电力现货试点地区陆续完成了按现货价格结算的工作。然而在实际结算过程中出现了大量结算不平衡费用,影响了市场的公平和效率。如何在市场设计阶段充分预估结算不平衡费用从而降低市场风险、提高市场效率是市场设计者需要重点关注的方向。文中从实时平衡市场中结算机制及市场主体交互行为的角度开展结算不平衡费用仿真分析。首先,提取与结算不平衡费用紧密联系的平衡市场要素。然后,基于主体代理模型(ABM)仿真方法建立平衡市场仿真模型,市场主体采用强化学习算法制定参与市场交易的交互策略。最后,通过算例详细分析了平衡服务提供商策略行为、不平衡结算价格机制和新能源免考核区间对结算不平衡费用的影响。

Simulation Technology of Environmental Impacts by Zero-energy Residential Buildings Based on Emergy Analysis Method

This paper presents a simulation technology of environmental impact for the building. By emergy analysis method,emergy costs of building( or construction engineering) can be calculated in the life cycle. It includes the engineering cost, environmental cost and social cost of building. Through integrating GIS technology with multi-agent technology,life cycle substance and energy metabolism of building( construction engineering) can be simulated and their environmental influence can be dynamically displayed. Based on the case study of entries works‘Sunny Inside'by Xiamen University in 2013 China International Solar Decathlon Competition,we discovered the changing pattern of surrounding environmental impact from waste streams of the zero-energy building and ordinary construction. The simulation results verified and showed the Odum principles of maximum power. This paper provides a new research perspective and integration approach for the environmental impact assessment in building and construction engineering. The result will help decision-making in design and construction engineering scheme.

Agent-based modeling in urban and architectura research： A brief literature review

Agent-based modeling （ABM） is an emerging modeling approach. In the past two decades, agent-based models have been increasingly adapted by social scientists, especially scientists in urban and geospatial studies, as an effective paradigm for framing the underlying problems of complex and dynamic processes. As a result, the literature of ABM research is growing rapidly, covering a diverse range of topics. This paper presents a systematic literature review of ABM research, and discusses both theoretical issues such as ABM definition and architecture, and practical issues such as ABM applications and development platforms. A comprehensive and up-to-date bibliography is presented.

Agent-based Modeling and Simulation for the Electricity Market with Residential Demand Response

Currently,critical peak load caused by residential customers has attracted utility companies and policymakers to pay more attention to residential demand response(RDR)programs.In typical RDR programs,residential customers react to the price or incentive-based signals,but the actions can fall behind flexible market situations.For those residential customers equipped with smart meters,they may contribute more DR loads if they can participate in DR events in a proactive way.In this paper,we propose a comprehensive market framework in which residential customers can provide proactive RDR actions in a day-ahead market(DAM).We model and evaluate the interactions between generation companies(GenCos),retailers,residential customers,and the independent system operator(ISO)via an agent-based modeling and simulation(ABMS)approach.The simulation framework contains two main procedures—the bottom-up modeling procedure and the reinforcement learning(RL)procedure.The bottom-up modeling procedure models the residential load profiles separately by household types to capture the RDR potential differences in advance so that residential customers may rationally provide automatic DR actions.Retailers and GenCos optimize their bidding strategies via the RL procedure.The modified optimization approach in this procedure can prevent the training results from falling into local optimum solutions.The ISO clears the DAM to maximize social welfare via Karush-Kuhn-Tucker(KKT)conditions.Based on realistic residential data in China,the proposed models and methods are verified and compared in a large multi-scenario test case with 30,000 residential households.Results show that proactive RDR programs and interactions between market entities may yield significant benefits for both the supply and demand sides.The models and methods in this paper may be used by utility companies,electricity retailers,market operators,and policy makers to evaluate the consequences of a proactive RDR and the interactions among multi-entities.

A multilevel and dynamic model of intragroup conflict and decision making:application of agent-based modeling

Although intragroup conflict has both multilevel and dynamic natures,less attention has been paid to establishing a holistic model of intragroup conflict that emerges across levels and unfolds over time.To address this research gap,we extend the multilevel view of intragroup conflict(Korsgaard et al.2008)to develop a multilevel and dynamic model of intragroup conflict that explicitly includes(1)the role of time and(2)the feedback loop to encompass the dynamic aspect of intragroup conflict.We further instantiate the extended model in the context of team decision-making.To achieve this and systematically examine the complex relationships,we use agentbased modeling and simulation(ABMS).We directly investigate how two types of intragroup conflict—task and relationship conflict—interplay with cross-level antecedences,interrelate and develop over time,and affect team outcomes.This study adds to the intragroup conflict research by extending the field with multilevel and dynamic views.

北京市大型医院空间优化与再配置的计算实验研究

医疗资源的合理布局是构建高质量医疗体系的重要基础。随着北京疏解工作的全面启动,以往高度集中布局的北京医疗资源需要重新配置。如何实现优质医疗资源空间布局的优化,既要解决“看病难、看病贵”,还不能加剧北京的“大城市病”,这是疏解面临的新课题。研究以计算社会科学的方法为基础,北京医疗资源疏解为背景,开发基于agent的城市医疗资源空间配置和布局的计算实验平台,讨论“点轴放射”模式和“组团”模式等不同布局情景下居民的居住选择和就医行为,“动态”观察和评估不同模式在平常和应急两种状态下资源配置的合理性和有效性。计算实验结果表明,“点轴放射”模式的医院布局在空间分布上更加均匀,能够随着人口的迁移互动逐渐形成自己的服务半径,效果略好于“组团”模式。然而,在灾情疫情等应急情形下,“组团”模式的医疗资源配置表现要显著好于“点轴放射”模式。研究表明,基于agent的建模和计算实验方法能够为利用真实数据建立现实模型展开这类布局事前研究和规划提供坚实的基础。

Agent-based simulation of alternative classroom evacuation scenarios

Due to the growing number of emergency accidents occurring around students, evacuation issues have become significantly important for both school officials and architects. Simply following construction codes cannot ensure that a building＇s layout is suitable for evacuation behaviors; therefore, to discover the suitable planning schemes, we have introduced an agentbased simulation model via Netlogo to investigate the interrelationships between evacuation efficiency and classroom layouts. Before conducting modeling experiments, both the simulation structure and the sensitivity to its parameter settings are examined by validation research and sensitivity analysis. Furthermore, to demonstrate the importance of conducting fire drills with students, two different types of behavior rules are designed to reflect the distinctive characteristics of students evacuating without instructions and students evacuating in good order. The general comparison results show us that the classroom layout with two exits shortens students＇ evacuation time, and the premeditated behavior rules, meaning that students who follow preset instructions to arrange their activities, not only escape faster but also have some advantages in ensuring their safety during the evacuation process. Moreover, at the end of this paper, several methods of improving this simulation model are proposed for more complex research in the future.

Agent行为建模与仿真研究的热点与趋势——基于CiteSpace图谱量化分析

目的:比较国内外Agent行为建模与仿真研究热点与趋势,为我国研究者更有效地应用Agent行为建模与仿真提供参考依据。方法:运用CiteSpace5.7R5软件对中国知网和Web of Science核心合集数据库2011年1月1日至2021年3月31日中有关Agent行为建模与仿真研究的文献进行图谱量化分析。结果:共检索到有效中文文献864篇、英文文献2323篇,国内发文量整体呈下降趋势,国外发文量整体呈上升趋势,发文量高的国家集中在发达国家,国外研究前沿已经延伸到物理学、金融学、哲学、生物学、物流学、人工智能等方面。国内研究热点主要集中在社会学、物理学、网络模型等方面。结论:Agent行为建模与仿真研究的应用范围较广泛,与国际相比国内Agent行为建模与仿真研究还存在一定的差距,研究深度和广度有待进一步拓展,国内应参考国际Agent行为建模与仿真研究的热点及前沿,探索适合我国特色的Agent行为建模与仿真系统体系,以促进我国Agent行为建模与仿真的发展。

Model construction and numerical simulation of arterial remodeling after stent implantation with variations of cell concentration

Differences in concentration of molecules can cause different molecular diffusion.This issue has not been well studied in the vascular remodeling process with regards to is-stent restenosis.This study designed and built a model to explore the effect of differences in vascular cell concentration on vascular remodeling.Finite element analysis(FEA)models and the agent-based models(ABMs)were established to simulate the damage and proliferation process of vascular smooth muscle cells(VSMCs)caused by coronary artery stent implantation.The FEA model simulated the expansion of the stent in the coronary artery,the tensile stress was captured and imported into the ABM,and the damaged VSMCs proliferated to reduce their damage level.VSMCs were randomly distributed within a defined domain,and the number of VSMCs in a unit volume(or area)was defined as the concentration of VSMCs.VSMCs with the smallest concentration of VSMCs will preferentially proliferate,which simulates the cell proliferation affected by the concentration of VSMCs.The results showed that after stent implantation,VSMCs proliferated gradually from the severely damaged stent area to the lumen until the artery reached a steady state.By comparison,the loss of arterial lumen and the number of newly grown VSMCs were greater in the presence of the concentration than in its absence.Cells made full use of the lumen space under the influence of concentration differences,so the concentration was of great significance to vascular remodeling.

基于Swarm的股权拍卖机制设计与仿真研究

基于多主体的建模仿真方法,运用particle swarm optimization(PSO)群体智能算法模拟信息交互条件下外部投资者估价变化的学习机制和演化规律,在机制设计的基础上,建立了实现风险投资退出的股权拍卖模型.在Swarm平台上对股权拍卖模型的仿真分析表明,所设计的股权拍卖机制能够显著地提高风险投资家的收益,并能帮助风险投资家预测外部投资者的估价和拍卖参与度的变化.对股权拍卖模型的参数仿真发现,风险投资家可以通过引入更多的外部投资者参与股权拍卖来进一步提高自己的收益;即便外部投资者过度强化单一学习能力,最终也可以得到相对理想的股权拍卖结果.本文的研究可以为风险投资家的策略选择提供参考依据.

Complexity Science and Cyber Operations: A Literature Survey

Complexity science is an interdisciplinary scientific field that analyzes systems as holistic entities consisting of characteristics beyond the sum of a system’s individual elements.This paper presents current research across the literature promoting cyber security as a complex adaptive system.We introduce complex systems concepts and fields of study,and deliver historical context,main themes,and current research relevant to cyber operations.Examples of cyber operations research leveraging agent-based modeling demonstrate the power of computational modeling grounded in complex systems principles.We discuss cyber operations as a scientific field,define current shortfalls for scientific rigor,and provide examples of how a complexity science foundation can further research and practice across a variety of cyber-based efforts.We propose standard definitions applicable to complex systems for cyber professionals and conclude with recommendations for future cyber operations research.