SHERPA: Mobile Wireless Data Capture for Piling Works

Abstract: The construction of rotary bored piles uses two interdependent site processes, requiring real-time information sharing between the workforce. This is currently achieved through manual recording of data and calculations on site, which can result in errors in pile construction, delays in the construction program, and additional costs from remedial works. This article describes the Stent Handheld ElectRonic Piling Assistant (SHERPA) which utilizes workforce driven mobile computers accessing a centrally site-located database through a mobile Wireless Local Area Network (WLAN). The WLAN utilizes the IEEE 802.11b protocol for wireless communications, which is becoming increasingly popular in the replacement of traditional wired networks within buildings. However, the application of such technology to construction has been restricted by its use of a wired Ethernet "backbone," which is impractical for the construction site. This problem has been addressed through the development of Wireless Network Cells (WNCs), which provide a portable and scalable solution to the challenges of implementing mobile networks for real-time data capture in the site environment.     

The computable city

By the year 2050, everything around us will be some form of computer. Already, we are seeing a massive convergence of computers and communications through various forms of media. Computerized highways are in prospect and smart buildings are almost upon us. As planners we are accustomed to using computers to advance our science and art but it would appear that the city itself is turning into a constellation of computers. The implications of this for city planning are enormous. New data sources emerging in real time, and software to understand many elements of the working of cities such as simulation games and GIS, are now widespread. The juxtaposition of media that a generation ago would have been regarded as unthinkable is generating entirely new opportunities for understanding and planning cities. This paper raises these issues through a travelogue across the Internet. Ideas for what is becoming possible in our domain are illustrated from that latest of networking triumphs, the World Wide Web, from which we draw examples of cities in situ, in vitro, in the abstract, in real time and in cyberspace. Point to our homepage http://www.casa.ucl.ac.uk/ and then click to generate these.     

INFORMATION TECHNOLOGY AND URBAN FORM New Wine in Old Bottles—Rejoinder to John P. Frendreis

ABSTRACT: The forecast—that technological change in communications and information technology will have little effect on urban form—is subject to challenge on several fronts. This comment develops three counterarguments, concluding that traditional conceptions of urban form blind us to significant roles that communications and information technology might play in shaping the character and experience of urban life. This article is a rejoinder to John P. Frendreis' “The Information Revolution and Urban Life.     

暖通空调系统的计算机控制管理第3讲 冷热源及水系统的监测控制

首先介绍冷冻站、热交换站和空调水系统的计算机控制管理系统的监测控制内容、传感器、执行器及相应的计算机和通讯网的配置。在此基础上较详细地讨论了水系统及冷热源的控制方案，其中包括常规的控制策略，特别讨论了在计算机通讯网的基础上充分利用各热用户运行状况信息的优化控制策略。鉴于冰蓄冷技术开始在我国推广，最后一节专门探讨了冰蓄冷系统的计算机控制与管理     

Graph‐Based Modeling of Information Flow Evolution and Propagation under V2V Communications‐Based Advanced Traveler Information Systems

A vehicle equipped with a vehicle‐to‐vehicle (V2V) communications capability can continuously update its knowledge on traffic conditions using its own experience and anonymously obtained travel experience data from other such equipped vehicles without any central coordination. In such a V2V communications‐based advanced traveler information system (ATIS), the dynamics of traffic flow and intervehicle communication lead to the time‐dependent vehicle knowledge on the traffic network conditions. In this context, this study proposes a graph‐based multilayer network framework to model the V2V‐based ATIS as a complex system which is composed of three coupled network layers: a physical traffic flow network, and virtual intervehicle communication and information flow networks. To determine the occurrence of V2V communication, the intervehicle communication layer is first constructed using the time‐dependent locations of vehicles in the traffic flow layer and intervehicle communication‐related constraints. Then an information flow network is constructed based on events in the traffic and intervehicle communication networks. The graph structure of this information flow network enables the efficient tracking of the time‐dependent vehicle knowledge of the traffic network conditions using a simple graph‐based reverse search algorithm and the storage of the information flow network as a single graph database. Further, the proposed framework provides a retrospective modeling capability to articulate explicitly how information flow evolves and propagates. These capabilities are critical to develop strategies for the rapid flow of useful information and traffic routing to enhance network performance. It also serves as a basic building block for the design of V2V‐based route guidance strategies to manage traffic conditions in congested networks. Synthetic experiments are used to compare the graph‐based approach to a simulation‐based approach, and illustrate both memory usage and computational time efficiencies.     

Human Response to Emergency Communication: A Review of Guidance on Alerts and Warning Messages for Emergencies in Buildings

The purpose of this article is to provide guidance on enhancing human response to emergency communication. This guidance can, in turn, help engineers improve the design of emergency notification and messaging systems, which, as a result, can help inform occupant response, reduce occupant evacuation time, and increase occupant safety. The article begins with a literature review on how people respond to emergencies. The Protective Action Decision Model, which describes the decision-making process that precedes human response in disaster events, is used as a framework for the literature collected as part of this review. This model is divided into three pre-decisional and five decisional processes. The method used to create the guidance document is then explained, including the six steps taken to review the literature collected (from 162 engineering and social science sources), generate findings from this literature, and compile the key statements found in the guidance document. Guidance on alerts, visual/audible warnings and dissemination of warning messages are provided. These are organized according to alert/warning type and dissemination method. The findings of the literature review include five guidance statements on alerts, 16 guidance statements on visual warnings, seven guidance statements on audible warnings and eight guidance statements on the dissemination of warning messages. Finally, guidance on emergency message testing, including language, readability and fire drills as a means of response testing, is provided. It is envisioned that this guidance will inform practitioners on the design of future emergency communications and subsequently enhances evacuee performance through a better understanding of the manner in which emergency information is processed and the tools available to provide such information.     

遥感数据下载软件在地质工作中的应用——以微图为例

遥感技术是20世纪60年代兴起的一种探测技术,是根据电磁波的理论,应用各种传感仪器对远距离目标所辐射和反射的电磁波信息,进行收集、处理,并最后成像,从而对地面各种景物进行探测。遥感技术集中了空间、电子、光学、计算机通信和地学等学科的最新成就,是当代高新技术的一个重要组成部分。国际上遥感技术的发展,将在未来15年将人类带入一个多层,立体,多角度,全方位和全天候对地观测的新时代。各种高、中、低轨道相结合,大、中、小卫星相互协同,高、中、低分辨率互补的全球对地观测系统,将能快速、及时地提供多种空间、时间和光谱分辨率的对地观测海量数据。本文以常用的遥感数据下载软件为例,介绍了目前主流遥感数据下载软件在地质领域的应用。     

Implications of cable TV for participatory democracy

Cable TV is not TV as we know it, and it is not cable TV as we know it. It uses coaxial cable that has us re-wire the cities yet again. The two-way ‘response’ system transmits images and sound one way downstream to the user including suggested answers to questions printed on the screen, for the user to choose from (ie Yes, No, Maybe, Never, Give me more). The user's digital signals are sent upstream to the headend computers, which also provide for information retrieval services and transactions such as banking and shopping. The user operates by pushing buttons in a hand-held console, these buttons relate to the set of offered answers, or items to buy. By contrast, the two-way ‘video-to-video’ interactively transmits images and sound. This face-to-face capability which was lost as cities grew bigger can now be had electronically, so a number of neighbourhood centres can discuss issues, in the same city or intercity, and others listen in.     

拟议中6类、7类布线系统的性能和应用前景

计算机与网络越来越快的速度对布线的性能提出了更高的要求。现有５类布线是否还能满足未来发展的需求？虽然厂商已推出了超５类，６类，７类产品，但国际上关于６类，７类布线的标准却迟迟没有正式发布。本文仅从实际应用的需求出发，试对拟议中的６类，７类布线的性能指标及其应用前景进行分析。     

A Distributed Computing Environment for Dynamic Traffic Operations

This study explores distributed computing techniques in the context of dynamic network algorithms for intelligent transportation systems (ITS) applications. ITS technologies such as Advanced Traveler Information Systems (ATIS) and Advanced Traffic Management Systems (ATMS) provide traffic-related information on-line for a new generation of models and methodologies that aim at the real-time enhancement of network performance and efficiency. However, existing sequential processing solution techniques and/or single-processor computational environments pre- clude translation of these methodologic and algorithmic advances to on-line operability due to the severe computational burden of processing networkwide time-dependent traffic-related data (such as volume, speed, occupancy, and classification). To address this problem, we investigate two remote procedure call (RPC)—based distributed computing techniques on a network of workstations. Computational results indicate that the distributed implementation performs better than sequential computation, although tradeoffs between communications overheads and computational savings become critical with the number of processors. This suggests a threshold number of processors for optimal computational performance depending on the specific problem and its solution logic. The results also illustrate the effects of congestion levels, loading profiles, and output data size on computational performance.     

Remote Sensing: Latest Developments and Uses

This paper considers currently available airborne and satellite-derived data suitable for monitoring coastal and river zones, and the potential offered by geographical information systems to manage this information. The main advantage of satellite data is the relatively low cost of acquisition over broad areas at regular intervals in time. Examples are (a) LANDSAT thematic mapper data and 'satellite pour l'observation de la terre'multi-spectral and panchromatic imagery which provide high resolution imagery for land-use mapping and bathymetric analysis, (b) National Oceanic and Atmospheric Administration's advanced very high resolution radiometer which provides a synoptic view of sea surface temperature and meteorological conditions, and (c) European remote sensing satellites whose array of sensors provide information on wave characteristics and wind speed and direction. In the field of geographical information systems, the challenge is to create systems which can both store the large quantity of data available and incorporate models which can predict the effects of change to the environment.     

The integration of communications networks in the intelligent building

An Intelligent Building Communications Network (IBN) is a ubiquitous network that integrates Telecommunications, an Intelligent Building Information System (IBIS) and Business Resources over a digital communications platform and has interoperability between systems. Implementation of an IBN is dependent on the migration of IBIS communications networks into the domain of telecommunication and the adoption of Open Systems Interconnection to standardise protocol development. A mechanism suitable to achieve this goal is the Integrated Services Digital Network (ISDN), a fully managed switched network service based on a 64 Kbps channel.     

Immanent Domain

A wave of emergent digital technology holds vast implications for the public sphere. Indeed, these new forms of mobile and ubiquitous systems, called pervasive computing , challenge some of our fundamental ideas about subjectivity, visibility, space, and the distinction between public and private. Together, these challenges reformulate our conception of the civic realm. From cell phones to wireless local area networks, smart buildings to embedded vehicular computers, an invisible web of digital technology already lies across the visible world creating new space for work, data, advertisement, investigation, communication, intimacy, and danger. This generation of computers is so well integrated with the environment that it will be difficult to distinguish between the two, which represents a profound transformation for everyday life.     

A Sustainable Funding and Financing Strategy for Urban Infrastructure Renewal in China

In a relatively short time, many of China’s cities have become major industrial, shipping, and financial hubs. To support this unprecedented growth and economic development, China has invested enormous sums to provide transportation, power, communications, sanitation, and other basic infrastructures. Although much of this investment has been in newer urban districts, old districts within existing cities still add value to the economy and are often repositories of China’s considerable cultural heritage. Maintaining compatibility between the old and the new is always challenging but the renewal of older infrastructure systems often lags behind due to a shortage of capital and difficulties in raising sufficient revenue to support replacement and upgrading of basic systems. This paper will examine the range of funding and financing options that are in use throughout the world to see what mix of public and private approaches might be most suitable for Chinese cities to adopt as part of a funding and financing strategy that will support enduring and sustainable renewal and redevelopment of older urban districts.     

Risk-based asset management: automated structural reliability assessment of geographically distributed pipeline networks for gas and water in the Netherlands

Pipeline networks for gas and water are the lifelines of our society. Most pipelines are buried, which obstructs direct monitoring of the pipes, and introduces the need for other techniques to provide network operators with information on the structural reliability of their network. One of the threats related to pipelines, possibly jeopardising the integrity of the network, is deformation of the subsurface surrounding the pipes, which imposes stress in the pipes. This paper describes the development of a fully computerised and automated model to calculate the probability of failure caused by subsurface deformation of pipes over time in the Netherlands. The objective is to provide failure probability information to network operators assisting the decision-making process regarding preventive measures, such as timely replacement. It will result in a reduction of costs associated with pipe failure, and lead to increased safety (e.g. explosion hazard) and certainty of delivery. The methodology used to develop the model is denoted as the STOOP system-of-systems. First results of the model are presented for a case study and show that different data sources and different models can be combined into a system of systems capable of performing predictive assessments.     

Development of Recurrent Neural Network Considering Temporal‐Spatial Input Dynamics for Freeway Travel Time Modeling

Abstract: The artificial neural network (ANN) is one advance approach to freeway travel time prediction. Various studies using different inputs have come to no consensus on the effects of input selections. In addition, very little discussion has been made on the temporal–spatial aspect of the ANN travel time prediction process. In this study, we employ an ANN ensemble technique to analyze the effects of various input settings on the ANN prediction performances. Volume, occupancy, and speed are used as inputs to predict travel times. The predictions are then compared against the travel times collected from the toll collection system in Houston. The results show speed or occupancy measured at the segment of interest may be used as sole input to produce acceptable predictions, but all three variables together tend to yield the best prediction results. The inclusion of inputs from both upstream and downstream segments is statistically better than using only the inputs from current segment. It also appears that the magnitude of prevailing segment travel time can be used as a guideline to set up temporal input delays for better prediction accuracies. The evaluation of spatiotemporal input interactions reveals that past information on downstream and current segments is useful in improving prediction accuracy whereas past inputs from the upstream location do not provide as much constructive information. Finally, a variant of the state‐space model (SSNN), namely time‐delayed state‐space neural network (TDSSNN), is proposed and compared against other popular ANN models. The comparison shows that the TDSSNN outperforms other networks and remains very comparable with the SSNN. Future research is needed to analyze TDSSNN's ability in corridor prediction settings.     

楼宇自控系统领域的网络通讯

阐述了楼宇自控系统中数据通讯和网络的重要性，介绍了不同类型的通讯网络，如ＬＡＮ、ＭＡＮ、ＷＡＮ等以及它们的优点，如文件服务器的集中信息存贮、远程打印、较高的通讯速度、现存系统的扩展等。     

Western Europe, current city expansion and the use of GIS

Garreau's concept of an “edge city” is discussed with regard to London and northwest Europe. It is argued that the employment of geographical information systems (GIS) will enable new forms of planning which have a degree of flexibility and responsiveness not found in traditional planning systems. Electronic networks can help to democratise a planning system and to generate plans which transcend the administrative boundaries of older cities. Greater integration between physical planning and the free market may also be possible. The argument is illustrated with reference to practice in the Paris region, the Netherlands, Belgium and the South England Edge City (SEEC).     

E-urbanism: E-commerce,migration, and the transformation of Taobao villages in urban China

The development of information and communications technology (ICT) has promoted the rapid growth of e-commerce, which has gradually changed the city. Networking and migration are also key driving forces for contemporary urban development. Although a growing body of literature has studied e-commerce development, there is a lack of theoretical and empirical research to understand the impact of e-commerce and migration on urbanism. This study is an attempt to fill the gap. It firstly proposes a concept framework of E-urbanism that includes three interwoven layers, namely of ICT infrastructure and production networks, social networks and power relations, and urban form and land use. The framework is then applied to understand the influence of e-commerce and migration on the socio-spatial transformation of Taobao villages in Guangzhou city, China. This article concludes that ICT infrastructure and production networks form the foundation of e-commerce development, while social networks of rural migrants are important sources of social capital in the formation of Taobao villages. The existing physical forms provide opportunities for e-commerce growth, which has in turn reshaped them. E-commerce is fundamentally revolutionizing urbanism, the intertwinement of social and spatial reorganization of the city.     

Cooperative control of a platoon of connected autonomous vehicles and unconnected human-driven vehicles

By using kinematic state information obtained through vehicle-to-vehicle communications, connected autonomous vehicles (CAVs) can drive cooperatively to alleviate shockwave propagation associated with traffic disturbances. However, during the transition to full autonomy, CAVs and human-driven vehicles (HDVs) will coexist on the road, creating mixed-flow traffic. The inherent heterogeneity and randomness in human driving behavior can generate additional disturbances in the traffic flow. Further, HDVs without communication functionality (unconnected HDVs) can cause the control performance of CAVs to degrade by negatively impacting platoon formation. To proactively mitigate the negative impacts of HDVs in mixed-flow traffic, this study proposes a cooperative control strategy with three components for platoons consisting of CAVs and unconnected HDVs: (i) a number estimator for estimating the number of HDVs between two CAVs, (ii) a kinematic state predictor for predicting the kinematic states of HDVs, and (iii) a multi-anticipative car-following controller (i.e., control strategy using kinematic state information of multiple preceding vehicles) for CAVs to maintain string stability and desired time headway. To initialize the proposed strategy, the number estimator is developed using a deep neural network (DNN). Then, a DNN-based kinematic state predictor predicts the kinematic states of HDVs for CAVs to enable multi-anticipative car-following control. The multi-anticipative car-following controller is implemented using an extended intelligent driver model-guided deep deterministic policy gradient algorithm, which ensures safety, string stability, and traffic efficiency. The effectiveness of the proposed control strategy is validated through numerical experiments using NGSIM data. Results indicate that the proposed strategy can produce accurate estimations of the number and the kinematic states of HDVs between CAVs. Further, it can achieve string stability while maintaining smaller time headways, compared to car-following models used for training guidance under different market penetration rates of CAVs, which significantly improves traffic smoothness and mobility.