群智感知中基于社交属性及有效用户计算的任务分发机制

随着无线传感器网络的高速发展和多种移动智能设备的普及,移动群智感知(mobile crowd sensing,MCS)成为移动计算的核心。利用群智感知可完成大规模、复杂环境及社会感知任务,其中任务分发是这种应用中的一个重要环节。针对任务分发过程中存在感知环境复杂、用户数量达不到要求、收集数据质量低等问题,提出一种基于社交属性及有效用户计算的任务分发机制(effective user calculation,EUC),该机制具有根据任务来筛选用户的特点,从用户角度看,EUC考虑了用户的社会性,由用户的社交网络传递相关信息来增加平台的有效用户数;从平台的角度看,EUC可根据任务的接收和提交情况,动态调整有效用户的积分,从而保障整个系统的有效用户数。理论分析和实验结果表明,所提出的机制可提高系统的任务分发效率,并改善了收集数据的质量。     

The simulation and analysis of pedestrian crowd and behavior

Pedestrian crowd in public buildings is usually a hidden trouble. The more serious the crowd, the higher the accident risk, and the heavier the casualties and loss may be. Based on the social force model, this paper puts forward an improved model which takes into account the anisotropic characteristic of pedestrian movement and the avoidance of dynamic congested areas. Furthermore, the algorithm has been optimized with the help of static force grid, so the simulation becomes more veritable and computational speed is also greatly accelerated. The improved model is also applied to research on the characters of pedestrian crowd, and the conclusion can provide a basis for the risk assessment of pedestrian crowd and the design of public buildings. Supported by the National Natural Science Foundation of China (Grant No. 50308002) and the Natural Science Foundation of Beijing (Grant No. 9052007)     

Inherent Noise‐Aware Insect Swarm Simulation

Collective behaviour of winged insects is a wondrous and familiar phenomenon in the real world. In this paper, we introduce a highly efficient field‐based approach to simulate various insect swarms. Its core idea is to construct a smooth yet noise‐aware governing velocity field that can be further decomposed into two sub‐fields: (i) a divergence‐free curl‐noise field to model noise‐induced movements of individual insects in a swarm, and (ii) an enhanced global velocity field to control navigational paths in a complex environment along which all the insects in a swarm fly. Through simulation experiments and comparisons with existing crowd simulation approaches, we demonstrate that our approach is effective to simulate various insect swarm behaviours including aggregation, positive phototaxis, sedation, mass‐migrating, and so on. Besides its high efficiency, our approach is very friendly to parallel implementation on GPUs (e.g. the speedup achieved through GPU acceleration is higher than 50 if the number of simulated insects is more than 10 000 on an off‐the‐shelf computer). Our approach is the first multi‐agent modelling system that introduces curl‐noise into agents' velocity field and uses its non‐scattering nature to maintain non‐colliding movements in 3D crowd simulation.     

一种基于动机理论的人群行为模型

如何构建行为可信的虚拟人是自主人群仿真中的关键问题。根据马斯洛的动机理论,建立自主人群的行为模型,该模型利用产生式规则,将刺激、动机和行为集成在一起。引入有限状态机描述刺激和动机的关系,虚拟人通过虚拟视觉感知刺激,虚拟人之间的局部碰撞检测通过排斥力控制。在微机上实现原型系统,实验结果表明,该模型能够较好地模拟自主群体行为。     

一种基于元胞自动机的人群疏散 仿真算法研究

以安徽博物院内人群疏散问题为例,根据最小费用最大流与广度优先搜索(BFS)方法提出了一种基于元胞自动机的人群疏散仿真算法.首先,算法通过设定数值矩阵,分别对人物状态、地形状态与影响人群逃离的因素进行量化; 其次,结合最小费用最大流的思想,建立人群在复杂地形中的逃离规则; 最后,应用该算法以疏散单层和多层人群为例进行仿真,结果显示博物院1层的疏散性能弱于2层,工作人员的疏散引导可大幅缩短疏散时间(由无人引导的4 423 s降至为1 876 s).对比3种不同算法的仿真结果显示,本文算法优于传统算法,与文献[7]算法接近,但本文算法因考虑了人群疏散时的心理因素,因此本文算法更符合实际.     

The response of grandstands driven by filtered Gaussian white noise processes

This paper presents a semi-analytical estimate of the response of a grandstand occupied by an active crowd and by a passive crowd. Filtered Gaussian white noise processes are used to approximate the loading terms representing an active crowd. Lumped biodynamic models with a single degree of freedom are included to reflect passive spectators occupying the structure. The response is described in terms of the first two moments, employing the Itô formula and the state augmentation method for the stationary time domain solution. The quality of the approximation is compared on the basis of three examples of varying complexity using Monte Carlo simulation based on a synthetic generator available in the literature. For comparative purposes, there is also a brief review of frequency domain estimates.     

基于群智感知的正念隐式社交交互系统设计

目的 构建基于群智感知的正念隐式社交交互系统,在用户个体间形成隐式互助关系,使用个体在正念中获得共鸣,提升正念效果,促进使用积极性,形成以社交为反馈方式的新型正念体验。方法 引入群智感知技术,搭建基于群智感知的正念隐式社交交互系统,包括信息收集端、信息处理端、软件使用端3大端口。结果 提出“隐联系、隐互助、隐共鸣”的隐式社交模型,以及基于群智感知的正念隐式社交交互系统构架,并通过“一段”APP的核心功能、信息构架、界面设计,对面向音乐的群智感知正念隐式社交交互系统进行实践验证。结论 基于群智感知的正念隐式社交交互系统挖掘正念中用户间的隐式联系,创造隐式社交这一网络社交新场景,对于群智感知在社交领域的应用提出新的应用模型。     

线索窃取调度中的预取策略

通过对线索窃取调度中问题的分析，提出了一种改进策略，称为线索预取策略（Ｐ－Ｆ－Ｓ）。在此策略中，通过改进的协议，可实现线索预取。由于用线索计算掩盖了线索转移，此策略减小了线索转移开销，同时，此协议对线索拌动和请求拥挤具有不同程度的解决。最后，应用Ｐ－Ｆ－Ｓ评价模型，证实了此算法的有效性。     

SPHERICAL UNCERTAINTIES IN DISCRETE-TIME SYSTEMS

The exact values of the limits of spherical uncertainties are derived that are admissible in a discrete-time dynamic system without affecting stability.     

电梯群控待梯人群识别技术研究

电梯群控系统中,候梯人群数量很难获得,降低了群控系统的控制性能。为了进一步完善群控系统的性能,提出一种待梯人群识别技术。此技术采用热释电红外传感器组实现对候梯人群数量进行模糊采集,并在微处理器上进行数据处理,再由CAN总线将信号传输到电梯群控系统主机。对待梯人群数量的采集、预处理及数据的传输,进行了软件及硬件设计,并进行了相关实验。此项研究将为电梯群优化调度系统提供重要的参数和依据。