Modelling the impacts of crowds on occupants in the built environment—A static,rule-based approach to human perception and movement

A building occupant’s experiences are not passive responses to environmental stimuli, but are the results of multifaceted, prolonged interactions between people and space. We present a framework and prototype software tool for logically reasoning about occupant perception and behaviour in the context of dynamic aspects of buildings in operation, based on qualitative deductive rules. In particular, we focus on the co-presence of different user groups and the resulting impact on perceptual and functional affordances of spatial layouts by utilising the concept of spatial artefacts. As a first proof of concept of our approach, we have implemented a prototype crowd analysis software tool in our new system ASP4BIM, developed specifically to support architectural design reasoning in the context of public-facing buildings with complex signage systems and diverse intended user groups. We evaluate our prototype on the Urban Sciences Building at Newcastle University, a large, state-of-the-art living laboratory and multipurpose academic building. Our findings are that the ASP4BIM-based prototype supports a range of novel query services for formally analysing the impacts of crowds on pedestrians that are logically derived through the use of qualitative deductive rules, that complements other powerful crowd analysis approaches such as agent-based simulation.     

Beyond intelligent interfaces: Exploring,analyzing, and creating success models of cooperative problem solving

Cooperative problem-solving systems are computer-based systems that augment a person's ability to create, reflect, design, decide, and reason. Our work focuses on supporting cooperative problem solving in the context of high-functionality computer systems. We show how the conceptual framework behind a given system determines crucial aspects of the system's behavior. Several systems are described that attempted to address specific shortcomings of prevailing assumptions, resulting in a new conceptual framework. To further test this resulting framework, we conducted an empirical study of a success model of cooperative problem solving between people in a large hardware store. The conceptual framework is instantiated in a number of new system-building efforts, which are described and discussed.     

基于场景结合的大规模动态群体可见性计算方法

动态场景的可见性计算对于大规模场景的实时渲染具有重要意义,其中运动中的大规模群体更给可见性计算带来了很大的开销.针对大规模动态群体在建筑物场景内部运动的情况,提出一种与场景结合的动态群体可见性计算方法.在预处理时,根据个体在不同仿真时刻的位置,将其绑定到相应的场景节点中;在实时绘制时,结合场景的可见性判断结果对动态群体中的个体进行可见性判断.实验结果表明,该方法能高效地剔除动态群体中的不可见个体,使大规模动态场景的实时绘制效率得到明显提高.     

Guided Crowd Evacuation: Approaches and Challenges

Evacuation leaders and/or equipment provide route and exit information for people and guide them to the expected destinations, which could make crowd evacuation more efficient in case of emergency. The purpose of this paper is to provide an overview of recent advances in guided crowd evacuation. Different guided crowd evacuation approaches are classified according to guidance approaches and technologies. A comprehensive analysis and comparison of crowd evacuation with static signage, dynamic signage, trained leader, mobile devices, mobile robot and wireless sensor networks are presented based on a single guidance mode perspective. In addition, the different evacuation guidance systems that use high-tech means such as advanced intelligent monitoring techniques, AI techniques, computer technology and intelligent inducing algorithms are reviewed from a system’s perspective. Future researches in the area of crowd evacuation are also discussed.      

Converting image to a gateway to an information portal for digital signage

Digital signage has recently emerged as a new channel for communicating with people in diverse domains such as advertising, shopping mall and public service. In this paper, we propose a novel data fusion method for converting an advertisement image into a gateway to an information portal based on steganography technology for digital signage. We make the information portal very flexible just by changing the link or by organizing the contents dynamically. Typical contents include product information and summary of user evaluation. To implement this scheme, we first register products of interest with their representative features and quick response (QR) code. The representative points are used for detecting products in images and their QR code is embedded into the detected product area using our steganography technique. We implement a prototype system based on our scheme, and show its effectiveness through extensive experiments.     

简述城市商业复合体标识及导视设计

文章主要从城市综合体的人流构成分析．不同目的人流访问目的地的路线分析。对现代城市复合体的标识导视系统的设计的原则,工艺及演化的趋势,作了简要的阐述。     

Automatic usability and stress analysis in mobile biometrics

This article focuses on the usability evaluation of biometric recognition systems in mobile devices. In particular, a behavioural modality has been used: the dynamic handwritten signature. Testing usability in behavioural modalities involves a big challenge due to the number of degrees of freedom that users have in interacting with sensors, as well as the variety of capture devices to be used. In this context we propose a usability evaluation that allows users to interact freely with the system while minimizing errors at the same time. The participants signed in a smartphone with a stylus through the different phases in the use of a biometric system: training, enrolment and verification. In addition, a profound study on the automation of the evaluation processes has been done, so as to reduce the resources employed. The influence of the users' stress has also been studied, to obtain conclusions on its impact on both the usability systems in scenarios where the user may suffer a certain level of stress, such as in courts, banks or even shopping. In brief, the results shown in this paper prove not only that a dynamic handwritten signature is a trustable solution for a large number of applications in the real world, but also that the evaluation of the usability of biometric systems can be carried out at lower costs and shorter duration.     

Interactional Order and Constructed Ways of Seeing with Touchless Imaging Systems in Surgery

While surgical practices are increasingly reliant on a range of digital imaging technologies, the ability for clinicians to interact and manipulate these digital representations in the operating theatre using traditional touch based interaction devices is constrained by the need to maintain sterility. To overcome these concerns with sterility, a number of researchers are have been developing ways of enabling interaction in the operating theatre using touchless interaction techniques such as gesture and voice to allow clinicians control of the systems. While there have been important technical strides in the area, there has been little in the way of understanding the use of these touchless systems in practice. With this in mind we present a touchless system developed for use during vascular surgery. We deployed the system in the endovascular suite of a large hospital for use in the context of real procedures. We present findings from a study of the system in use focusing on how, with touchless interaction, the visual resources were embedded and made meaningful in the collaborative practices of surgery. In particular we discuss the importance of direct and dynamic control of the images by the clinicians in the context of talk and in the context of other artefact use as well as the work performed by members of the clinical team to make themselves sensable by the system. We discuss the broader implications of these findings for how we think about the design, evaluation and use of these systems.     

Designing and evaluating a wizarded uncertainty-adaptive spoken dialogue tutoring system

We describe the design and evaluation of two different dynamic student uncertainty adaptations in wizarded versions of a spoken dialogue tutoring system. The two adaptive systems adapt to each student turn based on its uncertainty, after an unseen human “wizard” performs speech recognition and natural language understanding and annotates the turn for uncertainty. The design of our two uncertainty adaptations is based on a hypothesis in the literature that uncertainty is an “opportunity to learn”; both adaptations use additional substantive content to respond to uncertain turns, but the two adaptations vary in the complexity of these responses. The evaluation of our two uncertainty adaptations represents one of the first controlled experiments to investigate whether substantive dynamic responses to student affect can significantly improve performance in computer tutors. To our knowledge we are the first study to show that dynamically responding to uncertainty can significantly improve learning during computer tutoring. We also highlight our ongoing evaluation of our uncertainty-adaptive systems with respect to other important performance metrics, and we discuss how our corpus can be used by the wider computer speech and language community as a linguistic resource supporting further research on effective affect-adaptive spoken dialogue systems in general.     

Supporting the transition from hospital to home for premature infants using integrated mobile computing and sensor support

This paper reports on the requirements for, design of, and preliminary evaluation of a novel pervasive healthcare system for supporting the care of premature infants as they transition from hospital to home. In support of this system, we report the results of gesture sensing in a clinical setting and of interviews and focus groups with caregivers and clinicians who are involved in the postnatal transition to the home. From these results, we developed prototype systems for monitoring and tracking observations of behavioral and health-related data in the home, including a mobile phone-based capture and access system for caregivers, a sensing platform, and an activity recognition algorithm for automatically documenting infant movement. We describe the results of preliminary trials of both systems with an emphasis on the synergistic importance of bridging this transition. The results of these trials indicate that clinically relevant monitoring can be accomplished in the home, but there is still more to do to integrate these approaches into a comprehensive monitoring system for this population.     

Incorporating Software Visualization in the Design of Intelligent Diagnosis Systems for User Programming

Program diagnosis systems were developed to help users solve programming problems. By providing guidence on errors and misconceptions, these systems can help the users in writing programs and understanding their dynamic behavior. Features of software visualization which aim at providing visual and concrete depictions to the abstractions and operations of programs have also shown to be making programs more understandable. The main theme of this paper is to asses the usefulness of incorporating features of software visualization into the design of program diagnosis systems intended for novices. We report an empirical evaluation to assess the effectiveness of supporting visualization features during problem solving. The system used in the evaluation integrates visualzation and immediacy features and supports a model-tracing based approach to program diagnosis. Unlike other similar systems, our prototype system supports a more flexible style of interaction by increasing the grain size of diagnosis to a complete programming statement. The evaluation reported here seems to suggest that when supported with visualization features, systems for program diagnosis tend to be more effective in helping the users during problem solving.     

导向标识系统的个性化设计研究

导向标识系统在我们日常生活中是最常见最直观的城市空间元素。标识作为环境信息传达的载体,包含信息传达的有效性,设置的合理性与安全性几方面的内容。个性化设计已经是设计流行的趋势之一,标识系统的个性化即是在设计中注入的情感的、心理的、历史文化的、环境特色和谐的因素,从而使设计在发挥标识作用的同时,能给人带来或轻松愉快或亲切温馨或其他想不到的心理感受和体验。     

Improving and analyzing signage within a healthcare setting

Healthcare facilities are increasingly utilizing pictograms rather than text signs to help direct people. The purpose of this study was to analyze a wide variety of standardized healthcare pictograms and the effects of color contrasts and complexity for participants with both normal and impaired vision. Fifty (25 males, 25 females) participants completed a signage recognition questionnaire and identified pictograms while wearing vision simulators to represent specific visual impairment. The study showed that certain color contrasts, complexities and orientations can help or hinder comprehension of signage for people with and without visual impairment. High contrast signage with consistent pictograms involving human figures (not too detailed or too abstract) is most identifiable. Standardization of healthcare signage is recommended to speed up and aid the cognitive thought process in detecting signage and determining meaning. These fundamental signage principles are critical in producing an efficient, universal wayfinding system for healthcare facilities.     

Scalable context-dependent analysis of emergency egress models

Pervasive environments offer an increasing number of services to a large number of people moving within these environments, including timely information about where to go and when, and contextual information about the surrounding environment. This information may be conveyed to people through public displays or direct to a person’s mobile phone. People using these services interact with the system but they are also meeting other people and performing other activities as relevant opportunities arise. The design of such systems and the analysis of collective dynamic behaviour of people within them is a challenging problem. We present results on a novel usage of a scalable analysis technique in this context. We show the validity of an approach based on stochastic process-algebraic models by focussing on a representative example, i.e. emergency egress. The chosen case study has the advantage that detailed data is available from studies employing alternative analysis methods, making cross-methodology comparison possible. We also illustrate how realistic, context-dependent human behaviour, often observed in emergency egress, can naturally be embedded in the models, and how the effect of such behaviour on evacuation can be analysed in an efficient and scalable way. The proposed approach encompasses both the agent modelling viewpoint, as system behaviour emerges from specific (discrete) agent interaction, and the population viewpoint, when classes of homogeneous individuals are considered for a (continuous) approximation of overall system behaviour.     

基于云计算数字标牌管理平台的研究与设计

针对目前数字标牌网络系统的安装、运行、维修成本较高的情况,提出将云计算技术应用到数字标牌领域的设计思想．研究一种基于云计算智能数字标牌系统．它使信息推送更加精准化、个性化、低碳化。通过研究云计算体系结构和云服务层次的特点,实现了基于云计算智能数字标牌系统的设计。该设计解决了安装和运行数字标牌网络的低成本．实现多租户不同的个性化需求,为信息的时速性、多样化、特殊性带来极大的提升,正好满足了当前网络化数字标牌的市场需求．     

Performance evaluation of marked graphs by linear programming

Performance evaluation is an important issue for discrete event dynamic systems, which in many cases can be described in terms of the language of Petri nets. In particular, for marked graphs, a subclass of Petri nets, a formula for performance evaluation is widely known. That is, the ratio of the total execution time to the number of tokens in a cycle gives a lower bound for the cycle time of the system, and the maximum of these ratios over all cycles determines the overall system performance. However, we need to enumerate all directed cycles in a graph to apply this formula of performance evaluation. Carrying out this enumeration for an actual system is often impractical, since the number of cycles in a graph usually grows exponentially with the size of a system. We give a linear algebraic characterization for directed cycles, and based on this result, transform the problem of performance evaluation into a simple linear programming problem. A few explanatory examples are also given.     

Use of Digital Signage in a Distressed Community: An Example of Community Informatics

Community informatics is emerging as the framework for systematically approaching information systems from a “community” perspective. We discuss how a particular form of information technology, digital signage, was used to solve some of the problems faced by a city and a non-profit association in a distressed community. An analysis of this implementation shows that a community informatics perspective is essential to designing and implementing information and communication technologies systems for communities.     

An experimental study of inter-cell interference effects on system performance in unplanned wireless LAN deployments

In this paper, we report on our experimental study of the effects of inter-cell interference on IEEE 802.11 performance. Due to growing use of wireless LANs (WLANs) in residential areas and settings supporting flash crowds, chaotic unplanned deployments are becoming the norm rather than an exception. Environments in which these WLANs are deployed, have many nearby access points and stations on the same channel, either due to lack of coordination or insufficient available channels. Thus, inter-cell interference is common but not well-understood. According to conventional wisdom, the efficiency of an IEEE 802.11 network is determined by the number of active clients. However, we find that with a typical TCP-dominant workload, cumulative system throughput is characterized by the number of actively interfering access points rather than the number of clients. We verify that due to TCP flow control, the number of backlogged stations in such a network equals twice the number of active access points. Thus, a single access point network proves very robust even with over one hundred clients, while multiple interfering access points lead to a significant increase in collisions that reduces throughput and affects media traffic. Only two congested interfering cells prevent high quality VoIP calls. Based on these findings, we suggest a practical contention window adaptation technique using information on the number of nearby access points rather than clients. We also point out the need for collision-resilient rate adaptation in such a setting. Together these techniques can largely recover the 50% loss in cumulative throughput in a setting with four strongly interfering access points.     

A comparative study of partitioning methods for crowd simulations

The simulation of large crowds of autonomous agents with realistic behavior is still a challenge for several computer research communities. In order to handle large crowds, some scalable architectures have been proposed. Nevertheless, the effective use of distributed systems requires the use of partitioning methods that can properly distribute the workload generated by agents among the existing distributed resources.In this paper, we analyze the use of irregular shape regions (convex hulls) for solving the partitioning problem. We have compared a partitioning method based on convex hulls with two techniques that use rectangular regions. The performance evaluation results show that the convex hull method outperforms the rest of the considered methods in terms of both fitness function values and execution times, regardless of the movement pattern followed by the agents. These results show that the shape of the regions in the partition can improve the performance of the partitioning method, rather than the heuristic method used.     

Supporting virtual enterprise systems using agent coordination

Open environments like the Internet or corporate intranets enable a large number of interested enterprises to access, filter, process and present information on an as-needed basis. These environments support modern applications, such as virtual enterprises and interorganisational workflow management systems, which involve a number of heterogeneous resources, services and processes. However, any execution of a virtual enterprise system would yield to disjoining and error-prone behaviour without appropriate techniques to coordinate the various business processes. This paper reports on the design and implementation of a flexible agent-based framework for supporting the coordination of virtual enterprises and workflow management systems. The paper also shows how an agent coordination infrastructure, which is explained by social constraints, can impact on the engineering of highly dynamic virtual enterprises and workflow management systems by presenting a simple case study.