Smart sustainable cities – Exploring ICT solutions for reduced energy use in cities

This article explores the opportunities of using ICT as an enabling technology to reduce energy use in cities. An analytical framework is developed in which a typology of ICT opportunities is combined with a typology of household functions, i.e. all the activities that require energy. The energy used for household functions is calculated using a consumption-based lifecycle perspective. The analytical framework is intended to be of use to researchers, city and regional authorities and ICT companies interested in acquiring a better understanding of how ICT investments could contribute to reduce energy use in cities.     

Modeling and control of discrete event systems using finite state machines with variables and their applications in power grids

Control theories for discrete event systems modeled as finite state machines have been well developed to address various fundamental control issues. However, finite state machine model has long suffered from the problem of state explosion that renders it unsuitable for some practical applications. In an attempt to mitigate the state explosion problem, we propose an efficient representation that appends finite sets of variables to finite state machines in modeling discrete event systems. We also present the control synthesis techniques for such finite state machines with variables (FSMwV). We first present our notion and means of control under this representation. We next present our algorithms for both offline and online synthesis of safety control policies. We then apply these results to the control of electric power grids.     

Adaptive and context-aware service composition for IoT-based smart cities

Smart Cities are advancing towards an instrumented, integrated, and intelligent living space, where Internet of Things (IoT), mobile technologies and next generation networks are expected to play a key role. In smart cities, numerous IoT-based services are likely to be available and a key challenge is to allow mobile users perform their daily tasks dynamically, by integrating the services available in their vicinity. Semantic Service Oriented Architectures (SSOA) abstract the environment’s services and their functionalities as Semantic Web Services (SWS). However, existing service composition approaches based on SSOA do not support dynamic reasoning on user tasks and service behaviours to deal with the heterogeneity of IoT domains. In this paper, we present an adaptive service composition framework that supports such dynamic reasoning. The framework is based on wEASEL, an abstract service model representing services and user tasks in terms of their signature, specification (i.e., context-aware pre-conditions, post-conditions and effects) and conversation (i.e., behaviour with related data-flow and context-flow constraints). To evaluate our composition framework, we develop a novel OWLS-TC4-based testbed by combining simple and composite services. The evaluation shows that our wEASEL-based system performs more accurate composition and allows end-users to discover and investigate more composition opportunities than other approaches.     

一种基于智能卡的网络安全访问控制模型

随着网络应用的迅速发展,网络安全访问控制应用越来越重要,在了解和掌握常用访问控制技术的基础上,运用密码学的相关技术及其算法,并结合智能卡在网络访问控制技术实现上的优势,设计了一种实用、高效的基于智能卡技术的网络安全访问控制模型。     

基于无线射频的智能家居控制系统设计与实现余小华郑魏平

结合移动互联网技术、物联网技术、无线射频技术以及单片机嵌入式技术,利用SIM300GSM模块、nRF24101射频芯片与STC12C5A60S2单片机以及路由器组建基于微型Linux系统的核心控制器,同时利用nRF24101射频芯片、单片机和继电器模块组成控制终端,通过nRF24101芯片以2．4G频率将各从机与控制器进行无线组网。用户可通过网络可视化软件下发指令或者手机发送短信指令到核心控制器,核心控制器提取分析短信或控制指令并通过单片机发送指令到指定的终端,终端收到指令后将根据指令控制继电器的耦合和分离,实现电器的开启与关闭,并将控制后的状态反馈给核心控制器,控制器将实时状态通过网络或者短信告知用户控制成功与否,从而实现对智能家居的远程控制。测试结果表明设计的智能家居系统能完成相应的功能,通过各个模块的协调控制,能提高系统的可靠性和通用性。     

The Plan B OS for ubiquitous computing. Voice control, security, and terminals as case studies

The conventional approach to building pervasive environments relies on middleware to integrate different systems. Instead, we have built a system that can deal with these environments by exporting system resources through distributed virtual file systems. This requires no middleware, simplifies interoperation, and permits the application of general purpose tools to any system resource. A constraint-based file system import mechanism allows the system to adapt to changes in the environment and permits users to customize the environment and tailor adaptations according to their needs. The system has been in use for over a year to carry out our daily work and is underlying the smart space that we built for our department. The system, and some novel services, including ubiquitous voice interfaces, a distributed security architecture, and remote terminals for smart spaces, are also described in this paper.     

智能家居的发展方向与新技术

智能家居是人们对家居生活的一种理想。随着高新技术的不断发展,各技术领域智能程度的提高,智能家居也有了新的发展方向。本文首先给出了智能家居的发展方向,接着根据这些发展方向介绍了与此相关的信息技术、通信技术和无线射频技术等等,为智能家居的发展提供了有益的参考。     

Emerging ICT concepts for smart,safe and sustainable industrial systems

This editorial introduces the special issue on Emerging Information and Communication Technology (ICT) concepts for smart, safe and sustainable industrial systems in the Elsevier journal Computers in Industry. The 13 papers in this special issue were selected because of their high quality and also because they propose emerging ICT solutions that address at least one of the three dimensions we suggest as basic requirements to design usable future Industrial Systems that must be safe, smart and sustainable. Previous global discussions about the state of the art with regard to the topic of this special issue are provided, as well as exploratory guidelines for future research in this area.     

Swing-up and stabilization of a cart–pendulum system under restricted cart track length

This paper describes the swing-up and stabilization of a cart–pendulum system with a restricted cart track length and restricted control force using generalized energy control methods. Starting from a pendant position, the pendulum is swung up to the upright unstable equilibrium configuration using energy control principles. An “energy well” is built within the cart track to prevent the cart from going outside the limited length. When sufficient energy is acquired by the pendulum, it goes into a “cruise” mode when the acquired energy is maintained. Finally, when the pendulum is close to the upright configuration, a stabilizing controller is activated around a linear zone about the upright configuration. The proposed scheme has worked well both in simulation and a practical setup and the conditions for stability have been derived using the multiple Lyapunov functions approach.