Complex adaptive system theory,agent-based modeling,and simulation in dominant technology formation

Dominant technology formation is the key for the hightech industry to“cross the chasm”and gain an established foothold in the market(and hence disrupt the regime).Therefore,a stimulus-response model is proposed to investigate the dominant technology by exploring its formation process and mechanism.Specifically,based on complex adaptive system theory and the basic stimulus-response model,we use a combination of agent-based modeling and system dynamics modeling to capture the interactions between dominant technology and the socio-technical landscape.The results indicate the following:(i)The dynamic interaction is“stimulus-reaction-selection”,which promotes the dominant technology’s formation.(ii)The dominant technology’s formation can be described as a dynamic process in which the adaptation intensity of technology standards increases continuously until it becomes the leading technology under the dual action of internal and external mechanisms.(iii)The dominant technology’s formation in the high-tech industry is influenced by learning ability,the number of adopting users and adaptability.Therein,a“critical scale”of learning ability exists to promote the formation of leading technology:a large number of adopting users can promote the dominant technology’s formation by influencing the adaptive response of technology standards to the socio-technical landscape and the choice of technology standards by the socio-technical landscape.There is a minimum threshold and a maximum threshold for the role of adaptability in the dominant technology’s formation.(iv)The socio-technical landscape can promote the leading technology’s shaping in the high-tech industry,and different elements have different effects.This study promotes research on the formation mechanism of dominant technology in the high-tech industry,presents new perspectives and methods for researchers,and provides essential enlightenment for managers to formulate technology strategies.

Emulating a System Dynamics Model with Agent-Based Models: A Methodological Case Study in Simulation of Diabetes Progression

An agent-based simulation model hierarchy emulating disease states and behaviors critical to progression of diabetes type 2 was designed and implemented in the DEVS framework. This model was built to approximately reproduce some essential findings that were previously reported for a rather complex model of diabetes progression. Our models are translations of basicelements of this previously reported system dynamics model of diabetes. The system dynamics model, which mimics diabetes progression over an aggregated US population, was disaggregated and reconstructed bottom-up at the individual (agent) level. Four levels of model complexity were defined in order to systematically evaluate which parameters are needed to mimic outputs of the system dynamics model. The four estimated models attempted to replicate stock counts representing disease states in the system dynamics model while estimating impacts of an elderliness factor, obesity factor and health-related behavioral parameters. Health-related behavior was modeled as a simple realization of the Theory of Planned Behavior, a joint function of individual attitude and diffusion of social norms that spread over each agent’s social network. Although the most complex agent-based simulation model contained 31 adjustable parameters, all models were considerably less complex than the system dynamics model which required numerous time series inputs to make its predictions. All three elaborations of the baseline model provided significantly improved fits to the output of the system dynamics model, although behavioral factors appeared to contribute more than the elderliness factor. The results illustrate a promising approach to translate complex system dynamics models into agent-based model alternatives that are both conceptually simpler and capable of capturing main effects of complex local agent-agent interactions.

An agent-based model of agricultural land expansion in the mountain forest of Timor Island,Indonesia

The Mutis-Timau Forest Complex,located on Timor Island,Indonesia,is a mountainous tropical forest area that gradually decreases due to deforestation and forest degradation.Previous modelling studies based on patterns indicate that deforestation primarily occurs at lower elevations and near the boundaries of forests and settlements,often associated with shifting cultivation by local farmers.This study adopts a process-based modelling approach,specifically the agent-based model,to simulate land changes,particularly farmers'expansion of agricultural land around the Mutis mountain forest.The underlying concept of this agent-based approach is the interaction between the human and environmental systems.Farmers,representing the human system,interact with the land,which represents the environmental system,through land use decision-making mechanisms.The research was conducted in the Community Forest of the Timor Tengah Utara District,one of the sites within the Mutis-Timau Forest Complex with the highest deforestation rate.Land use change simulations were performed using agent-based modelling from 1999 to 2030,considering the socio-economic conditions of farmers,spatial preferences,land use decisions,and natural transitions.The results revealed that the agricultural area increased by 14%under the Business as Usual scenario and 5%under the Reducing Emission from Deforestation and Forest Degradation scenario,compared to the initial agricultural area of 245 hectares.The probability of farmers deciding to extend agricultural activities was positively associated with the number of livestock maintained by farmers and the size of the village area.Conversely,the likelihood of farmers opting for agricultural extensification decreased with an increase in the area of private land and the farmer's age.These findings are crucial for the managers of the Mutis-Timau Forest Complex and other relevant stakeholders,as they aid in arranging actions to combat deforestation,designing proper forest-related policies,and providing support for initiatives such as reducing emissions from deforestation and forest degradation programs or further incentive schemes.

基于MATLAB的汽车ABS液压制动仿真

ABS液压制动系统作为汽车制动系统的重要组成部分,对于汽车的制动性能和安全性有着至关重要的影响.基于此,设计一种基于MATLAB的汽车ABS液压制动仿真系统,并对带ABS的汽车和不带ABS的汽车进行液压制动仿真对比分析.结果表明,ABS能够缩减制动刹车距离,确保汽车制动时行驶更具安全性.

An agent-based simulation with NetLogo platform to evaluate forward osmosis process(PRO Mode)

Forward osmosis(FO), as an emerging technology, is influenced by different factors such as operating conditions,module characteristics, and membrane properties. The general aim of this study was to develop a suitable(flexible,comprehensive, and convenient to use) computational tool which is able to simulate osmosis through an asymmetric membrane oriented in pressure retarded osmosis(PRO) mode in a wide variety of scenarios. For this purpose, an agent-based model was created in NetLogo platform, which is an easy-to-use application environment with graphical visualization abilities and well suited for modeling a complex system evolving over time. The simulation results were validated with empirical data obtained from literature and a great agreement was observed. The effect of various parameters on process performance was investigated in terms of temperature,cross-flow velocity, length of the module, pure water permeability coefficient, and structural parameter of the membrane. Results demonstrated that the increase in all parameters, except structural parameter of the membrane and the length of module led to the increase of average water flux. Moreover, nine different draw solutes were selected in order to assess the influence of net bulk osmotic pressure difference between the draw solution(DS) and feed solution(FS)(known as the driving force of FO process) on water flux. Based on the findings of this paper, the performance of FO process(PRO mode) can be efficiently evaluated using the NetL ogo platform.

Simulation of Intermediate State Absorption Enhancement in Rare-Earth Ions by Polarization Modulated Femtosecond Laser Field

We extend the third perturbation theory to study the polarization control behavior of the intermediate state absorption in Nd^（3＋）ions. The results show that coherent interference can occur between the single-photon and three-photon excitation pathways, and depends on the central frequency of the femtosecond laser field. Moreover,single-photon and three-photon absorptions have different polarization control efficiencies, and the relative weight of three-photon absorption in the whole excitation processes can increase with increasing the laser intensity.Therefore, the enhancement or suppression of the intermediate state absorption can be realized and manipulated by properly designing the intensity and central frequency of the polarization modulated femtosecond laser field.This research can not only enrich theoretical research methods for the up-conversion luminescence manipulation of rare-earth ions, but also can provide a clear physical picture for understanding and controlling multi-photon absorption in a multiple energy level system.

基于ADAMS和Simulink联合仿真的ABS控制算法研究

为了减少车辆控制系统的开发时间和费用,联合仿真方法受到越来越多的重视。它结合了不同软件的优点,可以在设计阶段验证控制算法对车辆性能的影响。建立了ADAMS和Simulink的联合仿真模型,在各种工况下对防抱制动系统(ABS)的常用控制方法——逻辑门限值方法进行了验证。仿真结果与实验数据进行了对比,证明联合仿真方法对ABS系统设计切实可行。该方法大大提高了ABS匹配的效率。

基于AMESim与Simulink/Stateflow的汽车ABS联合建模与仿真研究

通过建立AMESim与Simulink/Stateflow的汽车ABS联合仿真模型,模仿了4独立通道制动系统的整车模型在低附着制动工况下的制动过程。AMESim与Simulink/Stateflow联合建模构成的4轮整车制动模型可以考虑更多因素对汽车实际运行工况的影响。仿真结果显示,该模型能很好的模拟真实的制动工况,缩短制动距离与节约制动时间,且易于变更参数以缩短设计周期。

基于Simulink/Stateflow的汽车ABS混合建模与仿真

汽车防抱死制动系统(ABS)是一种很关键的汽车主动安全技术。本文采用基于有限状态机的系统仿真方法,采用Simulink和Stateflow模块混合建模,对ABS模型中的连续系统和离散系统进行仿真。仿真结果表明,该混合仿真系统能比较真实地反映汽车ABS系统的实际工作过程,显著缩短制动距离,提高安全性。

基于MATLAB/Simulink的汽车ABS建模与分析

阐述了汽车防抱死制动系统(ABS)的工作原理,依据动力学的理论,在:MATLAB/Simulink模块中构建汽车ABS的数学模型,并在模型中加入PID调节环节。分析不同路况下车轮的滑移率与附着系数的关系,得到最佳滑移率。以保持最佳滑移率为目标对ABS模型进行仿真分析,利用汽车动力学的基本理论对所得结果进行评价。

基于Matlab/Simulink的汽车ABS系统的建模与仿真

以单轮车辆为研究对象,在Matlab/Simulink的环境下建立整车数学模型、双线性轮胎模型、液压制动系统模型和滑移率计算模型,设计PID控制器,对所建立的汽车ABS数学模型进行仿真研究,得出仿真曲线,并将仿真结果与无ABS作用时的制动结果进行对比。结果表明,建立的ABS数学模型可靠,能达到较为理想的制动效果。

基于Simulink/Stateflow的三轴车辆ABS系统仿真

车辆防抱死系统(ABS)是一种使用率较高的车辆主动安全技术。民用市场上ABS使用率已经达到80%,大幅度提高了车辆的安全行驶性能,但是ABS系统在军用装甲轮式车辆的运用较少。本文建立了基于某三轴轮式装甲车辆建立了制动器模型、轮胎模型、垂直载荷模型,组成了整车模型。然后利用Simulink/Stateflow建立以滑移率和角加速度为逻辑控制参量,在不同附着系数的路面上ABS制动器模型。给定初值条件,在一定门限值条件下对ABS模型进行仿真,得到仿真结果表明该仿真系统能够较为真实地反映车辆ABS系统的实际工作过程,有效的缩短制动距离,提高安全性。

基于ADAMS和Simulink的ABS和EBD的联合仿真

利用虚拟样机软件对装有ABS、EBD的整车的制动性能进行仿真。首先建立了整车的动力学模型，通过Control模块接口建立模型联合仿真的输入输出参数，在Matlab／simulink下建立以滑移率为逻辑门限的控制策略，对分别装有ABS和EBD的整车直线制动过程进行了联合仿真，得到EBD具有较好的制动稳定性。

COVID-19 transmission in U.S.transit buses:A scenario-based approach with agent-based simulation modeling(ABSM)

The transit bus environment is considered one of the primary sources of transmission of the COVID-19(SARSCoV-2)virus.Modeling disease transmission in public buses remains a challenge,especially with uncertainties in passenger boarding,alighting,and onboard movements.Although there are initial findings on the effectiveness of some of the mitigation policies(such as face-covering and ventilation),evidence is scarce on how these policies could affect the onboard transmission risk under a realistic bus setting considering different headways,boarding and alighting patterns,and seating capacity control.This study examines the specific policy regimes that transit agencies implemented during early phases of the COVID-19 pandemic in USA,in which it brings crucial insights on combating current and future epidemics.We use an agent-based simulation model(ABSM)based on standard design characteristics for urban buses in USA and two different service frequency settings(10-min and 20-min headways).We find that wearing face-coverings(surgical masks)significantly reduces onboard transmission rates,from no mitigation rates of 85%in higher-frequency buses and 75%in lower-frequency buses to 12.5%.The most effective prevention outcome is the combination of KN-95 masks,open window policies,and half-capacity seating control during higher-frequency bus services,with an outcome of nearly 0%onboard infection rate.Our results advance understanding of COVID-19 risks in the urban bus environment and contribute to effective mitigation policy design,which is crucial to ensuring passenger safety.The findings of this study provide important policy implications for operational adjustment and safety protocols as transit agencies seek to plan for future emergencies.

基于ADAMS/Simulink的汽车ABS联合仿真实例分析

利用ADAMS／Controls模块将基于ADAMS2005的整车动力学模型和基于MATLAB6．5的ABS控制模型结合起来．以实例的方式详细介绍了联合仿真建模过程以及两种软件之间接口的具体实现方法．为实现不同领域复杂模型的仿真研究提供了一定的参考价值。结果表明了联合仿真方法的实用性和可行性。

基于simulink的ABS作用下的电机制动仿真

为探究电动汽车在ABS作用下的电机制动特性,本文基于汽车单轮模型,建立电动汽车动力学模型,构建液压制动系统传递函数,设计基于PID控制原理的ABS模型。选用永磁同步电机,采用id=0控制策略,利用坐标变换原理,对永磁同步电机进行矢量控制,并起制动作用。设计制动力传输系统,实现制动力矩的传递。设定单轮电动汽车模型参数及制动初速度为25 m/s,利用simulink建立电动汽车单轮制动模型并进行仿真实验。研究分析制动过程中,在ABS作用下,单轮电动汽车模型的滑移率的变化情况;在有无电机制动情况下,液压制动力矩的变化对比;电机制动时,定子三相输出电流的变化情况。仿真结果表明:制动时,电机转子切割磁感线,产生感应电流,则电机回收部分制动能量,该模型能够得出可观的仿真结果。

A goal-based approach for modeling and simulation of different types of system-of-systems

A system of systems(SoS)composes a set of independent constituent systems(CSs),where the degree of authority to control the independence of CSs varies,depending on different SoS types.Key researchers describe four SoS types with descending levels of central authority:directed,acknowledged,collaborative and virtual.Although the definitions have been recognized in SoS engineering,what is challenging is the difficulty of translating these definitions into models and simulation environments.Thus,we provide a goal-based method including a mathematical baseline to translate these definitions into more effective agent-based modeling and simulations.First,we construct the theoretical models of CS and SoS.Based on the theoretical models,we analyze the degree of authority influenced by SoS characteristics.Next,we propose a definition of SoS types by quantitatively explaining the degree of authority.Finally,we recognize the differences between acknowledged SoS and collaborative SoS using a migrating waterfowl flock by an agentbased model(ABM)simulation.This paper contributes to the SoS body of knowledge by increasing our understanding of the degree of authority in an SoS,so we may identify suitable SoS types to achieve SoS goals by modeling and simulation.

电动汽车电控液压制动系统CarSim/Simulink联合仿真研究

针对某款国产电动汽车的电控液压制动系统,文章基于滑移率的比例-积分-微分(PID)控制提出了防抱死制动系统(ABS)模型,以改善车辆制动性能,提高在对开路面上的制动有效性和安全性。首先,使用Simulink软件建立液压电控制动系统的动力学模型;然后,基于滑移率设计PID控制器,并通过1/4车辆模型验证其有效性;最后,利用S函数将ABS控制器的Simulink模型输入CarSim平台中,开展CarSim/Simulink双平台联合控制仿真。结果表明,基于滑移率的PID控制的ABS对比无ABS的车辆,制动性能更加优越,在对开路面上制动稳定性更加明显。

基于Simulink的汽车ABS仿真分析

针对汽车在有无ABS情况下制动能否保证良好的稳定和制动性的问题,对汽车整个ABS系统模型进行了仿真研究。对单轮车辆模型进行了动力学分析,得出了其车辆动力学数学公式,然后利用Simulink搭建了单轮车辆模型的数学仿真模型;依次分析了基于魔术公式的汽车轮胎模型、制动系统模型、滑移率模型以及PID控制模型的数学公式,搭建了相关仿真模型;最后将各个模块组合成了一个完整的汽车ABS仿真模型,并对有无ABS下的汽车制动工况进行了对比。研究结果表明:所建立的ABS系统模型可靠,在制动过程中具有良好的稳定和制动性。

Assessing the impacts of traffic calming at network level:A multimodal agent-based simulation

The reduction of speed limits in urban roads through traffic calming schemes intends to ensure safer traffic conditions among road users by reducing the probability related to the occurrence of severe accident.Looking it from a different perspective,traffic calming measures can potentially resolve congestion problems at the same time by lowering the overall accessibility and attractiveness of private cars in urban areas.This study proposes a new methodological approach to explore and assess the direct impacts of traffic calming in the transport system efficiency of a metropolitan area.The multi-agent transport simulation(MATSim)and Open-Berlin scenario are utilized to perform this simulation experiment.By developing a new external tool,the free flow speed and road capacity of each network link is updated based on new speed limits and different compliance rates,which are defined per road hierarchy level.The test scenarios that are formulated present radical conditions,where the speed limit in most urban roads of Berlin drops to 30 km/h or even 15 km/h.The findings of this study show a considerably high increase in trips,passenger hours,and passenger kilometers using public transport modes,when traffic calming links are introduced,the reserve change is observed in private cars trips.Although the speed limits are decreased in inner urban roads in most of the scenarios,the decrease of average travel speed of private cars is not so high as it was expected.Surprisingly,private cars are used for longer distances in all test scenarios.Car drivers seem to use already existed motorways and private road to commute.In simulations,driver compliance to the new speed limits seems to be a determinant factor that is strongly influenced by the design interventions applied in a traffic calming area.