Resilience Factors Reconciled with Complexity: The Dynamics of Order and Disorder

One of the main challenges in crisis management is to assess, ahead of time, the resilience of a system before a crisis erupts (pandemic, computer bug with large‐scale effects, cascade effects in critical infrastructure, etc.). In this article, we propose to reconcile the multiple and sometimes divergent definition of resilience by explaining the complementarity of stability and adaptability inherent to the concept. Also, we integrate a new dimension to the assessment of resilience by analysing the dynamics of negentropy (order, stability) and entropy (disorder, change) between factors. Until now, the evaluation of organizational and interorganizational resilience focused on analysing the presence or absence of resilience factors. With this new dimension, we show the complementarity and interdependence of resilience factors. Finally, we demonstrate how resilience is based on both favourable order and favourable disorder which create diversity and conformity in the system, while vulnerability relies on unfavourable order and unfavourable disorder.     

The Dynamics of Change [About the Cover]

This issue's cover features art by San Base. In this article, Base describes his work and his process.     

Probabilistic Modeling of Scene Dynamics for Applications in Visual Surveillance

We propose a novel method to model and learn the scene activity, observed by a static camera. The proposed model is very general and can be applied for solution of a variety of problems. The motion patterns of objects in the scene are modeled in the form of a multivariate nonparametric probability density function of spatiotemporal variables (object locations and transition times between them). Kernel Density Estimation is used to learn this model in a completely unsupervised fashion. Learning is accomplished by observing the trajectories of objects by a static camera over extended periods of time. It encodes the probabilistic nature of the behavior of moving objects in the scene and is useful for activity analysis applications, such as persistent tracking and anomalous motion detection. In addition, the model also captures salient scene features, such as the areas of occlusion and most likely paths. Once the model is learned, we use a unified Markov Chain Monte Carlo (MCMC)-based framework for generating the most likely paths in the scene, improving foreground detection, persistent labeling of objects during tracking, and deciding whether a given trajectory represents an anomaly to the observed motion patterns. Experiments with real-world videos are reported which validate the proposed approach.     

城市虚拟地理场景非定标三维重建算法仿真

为建立城市地理场景,用于辅助城市规划高度逼真、运行可靠的虚拟场景,提出城市虚拟地理场景非定标三维重建算法.使用几何节点、灯光节点、组合节点等构成简单的虚拟城市场景结构,以深度遍历方式获取楼房、灯光等位置信息;确定相机坐标系与世界坐标系,采用消失点相机自定标方法建立方程组,获得相机内参数矩阵,结合Moravec基本思想,...     

The TTA's Approach to Resilience after Transient Upsets

The Time-Triggered Architecture, as architecture for safety-critical real-time applications, incorporates fault-tolerance mechanisms to ensure correct system operation despite failures. The primary fault hypothesis of the TTA claims to tolerate either the arbitrary failure of any one of its nodes or the passively arbitrary failure of any one of its communication channels. To cover these failure modes, active redundancy techniques are used, which basically means that nodes and channels are physically replicated. The primary fault hypothesis, is, however, not strong enough for certain applications that have to tolerate transient upsets of multiple, possibly all, components in the system. Such a transient upset of the system may break up the synchrony of the nodes and leave disjoined sets of nodes synchronized to each other while the overall synchronization is lost. Although the TTA provides a clique avoidance algorithm that is able to correct a wide class of such multiple transient failures, a stronger algorithm is needed for full coverage. In this paper we discuss a secondary fault hypothesis for the TTA that addresses the transient upset of multiple components and present a new clique resolving algorithm based on the TTA's integrated diagnosis and startup service. This paper is a revised version of Steiner et al. (2003). This work has been funded by the European Project DECOS (Project number: IST-511764). Michael Paulitsch is currently affiliated with Honeywell International.     

Geographic,Geometrical and Semantic Reconstruction of Urban Scene from High Resolution Oblique Aerial Images

An effective approach is proposed for 3D urban scene reconstruction in the form of point cloud with semantic labeling. Starting from high resolution oblique aerial images, our approach proceeds through three main stages:geographic reconstruction, geometrical reconstruction and semantic reconstruction. The absolute position and orientation of all the cameras relative to the real world are recovered in the geographic reconstruction stage. Then, in the geometrical reconstruction stage, an improved multi-view stereo matching method is employed to produce 3D dense points with color and normal information by taking into account the prior knowledge of aerial imagery. Finally the point cloud is classified into three classes (building, vegetation, and ground) by a rule-based hierarchical approach in the semantic reconstruction step. Experiments on complex urban scene show that our proposed 3-stage approach could generate reasonable reconstruction result robustly and efficiently. By comparing our final semantic reconstruction result with the manually labeled ground truth, classification accuracies from 86.75% to 93.02% are obtained.      

地理信息数据变化检测系统的研究与实现

针对地理信息数据变化的需求,提出一种对地理信息数据进行变化检测的地理信息系统设计方案。探讨变化检测系统的设计思想、功能及系统架构,运用ArcObjects, ArcSDE及Oracle数据库等相关技术进行实现,检测出不同时期地理数据之间的变化信息。实例应用结果表明,该系统对地理信息数据变化的检测具有较高的准确性。     

The Architecture of Connectivity: A Key to Network Vulnerability,Complexity and Resilience

This paper highlights the relevance of connectivity and its architecture as a general conceptual framework which underlies and integrates the concepts of network vulnerability, complexity, and resilience. In particular, it will be pointed out that connectivity architecture can be considered an explicit key element for network vulnerability and shock propagation. While the relevance of the various connectivity configurations is not clearly emphasised in the dynamic complexity models of the space-economy, it appears to play a primary role in network analysis. In this regard, the emerging recognition of connectivity architecture in relation to hubs ? and hierarchies of hubs ? in a complex network will help the enhancement of network resilience. The paper develops as follows. First, the notion of network vulnerability, which refers not only to the phenomenon of shocks, but also to the propagation of shocks in a network, will be examined. Here it appears that modelling vulnerability and shock propagation, also jointly with cascading disaster models, is strongly based on connectivity issues. The question is: How can conventional (complex) system dynamic modelling, as well as network modelling, take into account these shocks and connectivity dynamics from the methodological viewpoint? A review in this respect shows how connectivity is a ‘hidden’ element in these complexity models, for example, in chaos or (dynamic) competition models, where interaction parameter values might lead to vulnerable domains and chaotic behaviour. On the contrary, connectivity and its various topologies have a distinct, primary role in network analysis. The issue of network resilience appears therefore to be the ‘response’ to vulnerability and chaos, calling for robustness and stability of the network in the presence of shocks and disruptions. Resilience analysis refers to the speed at which a network returns to its equilibrium after a shock, as well as to the perturbations/shocks that can be absorbed before the network is induced into some other equilibrium (adaptivity). Connectivity is relevant here, but not often considered in spatial economics. In order to reach a unified methodological framework, attention will finally be paid to a complementary analysis of the (dynamic) concepts of vulnerability and resilience. In this light, chaos models/properties might be seen in a positive perspective, since small changes can lead to uncertain and unstable effects, but also, thanks to connectivity, to new equilibria which are not necessarily negative. Thus, the architecture of connectivity, in its interdisciplinary insights, can be considered as a fundamental (and analytical) approach for identifying vulnerability and resilience patterns in complex networks.

     

Resilience: An Evolutionary Approach to Spatial Economic Systems

The concept of resilience has received a great deal of attention in the past decades. Starting from the first fundamental definitions offered by Holling, Pimms and Perrings in an economic-ecological modeling context, the present paper explores the evolution of the resilience concept—as well as related different measures—in both a continuous and discrete time setting.From this perspective, the paper explores the relevance of the resilience concept in socio-economic systems, by focussing the attention on the relationships among resilience, transition dynamics and lock-in effects, in particular in the light of the dynamics of technological innovation diffusion and adaptive behaviour of firms. In this framework we will describe an empirical application, in which the resilience and dynamics of the West-German labour market will be investigated. This empirical illustration is offered by making use of an algorithm constructed for detecting Lyapunov exponents, so as to classify the resilience among employment sectors in our case study.     

面向战略决策的大规模群体行为视景仿真研究

根据面向战略决策的大规模群体行为视景仿真具有“海量“运算和图形渲染处理的特点,构建了该类型仿真的总计技术方案并详细论述了三维虚拟人的制作与其动作行为的生成过程.在此基础上给出了如何应用Geofusion平台在描绘群体行为的整体效果和如何用OpenGVS平台来渲染出逼真的三维视景.这样不仅可以使战略决策人员能更清楚地了解战争行动可能会给社会群体带来什么样的影响,而且可以掌握其影响的程度,这将对提高战略决策的合理性与准确性具有重要的现实意义.     

一种从MPEG视频流中快速分割镜头的算法

镜头分割算法是实现视频检索的关键,本文提出一种针对MPEG视频流的快速分割镜头的算法,介绍了该算法的基本原理与实现过程。该算法利用压缩视频中的可用信息,通过计算帧的内编码宏块数量的比例作为是否需要进行镜头分割判别的标识,进而计算MPEG视频流B帧各宏块编码类型来检测发生镜头分割的帧住置,并进行了相关的实验。实验
结果表明,该算法能快速有效地检测镜头分割,且计算量较小。     

基于DC系数和运动矢量的快速场景分割算法

场景分割技术是动态视频分析和基于内容的视频检索的基础，以检测出来的场景作为基本单元，可以进一步对视频内容进行分析和建立索引．本文旨在提出一种基于MPEG压缩视频流的场景分割算法，利用MPEG数据流中已有的DCT DC系数和运动矢量，来检测场景的变换，从而实现场景分割，针对实际视频流中场景突变和渐变两类变换．本文提出两种方法分别处理不同情况，对于突变检测，该算法可以定位到帧，由于该算法进行最小程度的解码，降低了计算复杂度，因而大大提高了检测速度．     

CBERS-1图像预处理几何定位精度及景中心偏移在轨测试方法

阐述了对CBERS-1图像预处理几何定位精度及景中心偏移进行测试的技术方法及流程，并评价了测试数据，显示其误差有一定的解释性，可作为改进图像质量的一种依据。     

汽车进厂煤采样机控制系统的研制

采用ControX(开物)2000监控系统与PLC二级控制,研制出了汽车进厂煤采样机的控制系统.论述了PLC控制可编程序控制器对交流电机启、停的控制,并创造性提出了采用漫反射式光电开关进行汽车定位的方法.     

展示设计中的情景化设计

情景化设计在展示设计中的应用,起到了提高信息传输和接收速率的作用,使信息的传达更加顺畅。情景化设计适用于各种形式的展示空间,比如博览会、展览会、博物馆、商业卖场、橱窗展示等等。情景化设计可以准确体现展示主题,并且能够满足目标观众的各种需求。因此,我们需要深入研究,总结出情景化设计应用在展示设计中的多种方法。     

软件需求变更管理的系统动力学仿真建模

软件需求变更频繁发生,给软件项目造成了诸多威胁.能否对需求变更进行有效的控制管理,决定着软件的成败.使用系统动力学方法对软件需求变更管理过程进行仿真建模,可以动态地分析并预测需求变更产生的原因以及变更对软件项目造成的影响;对软件需求变更管理过程改进进行系统动力学仿真,亦可以辅助软件项目组织选择合适的过程改进策略.因此,基于系统动力学方法,参考了敏捷过程进行开源软件需求变更管理过程的建模和模型检测.以Spring Framework项目为研究案例,进行该项目3.2.x分支的软件需求变更管理过程的系统动力学仿真分析,并对需求变更管理进行过程改进仿真.通过对过程改进的仿真结果进行比对,说明各改进策略均降低了基线数据的软件缺陷率,提高了软件质量.根据软件项目的成本和进度要求,给出了过程改进建议.     

VEACON: A Vehicular Accident Ontology designed to improve safety on the roads

Vehicles are nowadays provided with a variety of new sensors capable of gathering information about themselves and from their surroundings. In a near future, these vehicles will also be capable of sharing all the harvested information, with the surrounding environment and among nearby vehicles over smart wireless links. They will also be able to connect with emergency services in case of accidents. Hence, distributed applications based on Vehicular Networks (VNs) will need to agree on a ‘common understanding’ of context for interoperability, and, therefore, it is necessary to create a standard structure which enables data interoperability among all the different entities involved in transportation systems. In this paper, we focus on traffic safety applications; specifically, we present the VEhicular ACcident ONtology (VEACON) designed to improve traffic safety. Our ontology combines the information collected when an accident occurs, and the data available in the General Estimates System (GES) accidents database. We assess the reliability of our proposal using both realistic crash tests, held in the facilities of Applus+ IDIADA in Tarragona, Spain, and Vehicular Network simulations, based on the ns-2 simulation tool. Experimental results highlight that both nearby vehicles and infrastructure elements (RSUs) are correctly notified about an accident in just a few seconds, increasing the emergency services notification effectiveness.