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1.
Huber  J.F. 《Computer》2002,35(10):100-102
The promise of ubiquitous computing is a future in which highly specialized, embedded computing devices operate seamlessly within the everyday environment and are transparent to users. Realizing this vision will require next-generation networks to support mobile multimedia devices with capabilities well beyond those of today's handsets. These networks will exploit wideband radio access technologies and IP-based protocols to provide IP transparency-all network elements support IP; mobility management for a globally networked environment; unique addressing for every user; personalization of information; positioning to enable location-dependent services; and end-to-end security. Such functionality requires more than providing wireless Internet access and e-mail.  相似文献   

2.
Location-based services in ubiquitous computing environments   总被引:1,自引:0,他引:1  
This paper presents a framework for providing dynamically deployable services in ubiquitous computing settings. The goal of the framework is to provide people, places, and objects with computational functionalities to support and annotate them. Using RFID-based tracking systems, the framework detects the locations of physical entities, such as people or things, and deploys services bound to the entities at proper computing devices near where they are located. It enables location-based and personalized information services to be implemented as mobile agents and operated at stationary or mobile computing devices, which are at appropriate locations, even if the services do not have any location-information. This paper presents the rationale, design, implementation, and applications of our prototype infrastructure.  相似文献   

3.
随着移动计算领域的兴起,基于位置的服务越来越受青睐。目前各种室内定位的方法层出不穷,由于室内广泛部署了无线基础设施,基于WiFi指纹信息的室内定位技术是其主流方法。设备异构和室内环境变化是影响定位精度的主要因素。本文针对以上两个问题,提出一种层次Levenshtein距离(HLD)的WiFi指纹距离计算算法,实现异构设备的指纹无校准比对。将不同移动设备采集的RSSI信息转化为AP序列,根据AP对应的RSSI值的差异性计算其层次能级,结合Levenshtein距离计算WiFi指纹之间的距离。对于需定位的WiFi指纹RSSI信息,利用HLD算法获取K个近邻,采用WKNN算法进行预测定位。实验中,为了验证算法的鲁棒性和有效性,在3种不同类型的室内环境中采用5种不同的移动设备来采集WiFi的RSSI信息,其定位的平均精度达1.5 m。  相似文献   

4.
This issue includes four works in process on issues and applications in location-aware computing: letting users set and control privacy policies when they use location-aware applications, cold-starting recommender systems for mobile location-aware services, aggregating contextual information for location-based applications, and applying location-based services to public transportation environments. The department also includes a report on lightweight virtualization of low-power wireless personal area networks.  相似文献   

5.
蓝牙技术及其在遥控器中的应用   总被引:1,自引:0,他引:1  
蓝牙技术是一种短距离无线通讯技术,在计算机、信息家电以及各种移动设备中嵌入蓝牙技术,能够给用户带来极大的方便。同时,用蓝牙技术取代设备与设备之间的电缆,能够对无线移动数字通讯业务带来巨大的促进作用,本文简要介绍蓝牙技术,并且以蓝牙技术在遥控器中的应用说明如何实现蓝牙的应用模型。  相似文献   

6.
Digital library services in the mobile computing have come into our daily life with the development of wireless communication and the manufacture of mobile devices. Digital libraries have collected large-scaled data for providing information service. However, there are still many problems such as limitations of computing on mobile devices and data transmission problems in the wireless network. This paper proposes a synergetic mechanism for digital library to provide information service in the mobile and cloud computing environment, which combines the digital library servers, mobile hosts and personal cloud space into a synergetic work group seamlessly. The proposed mechanism integrates the strong computing and large-scaled storage ability of cloud computing together with the convenience of mobile computing. It could help promoting knowledge sharing and improve work efficiency of users in the mobile and cloud computing environment.  相似文献   

7.
Mobile payments     
Varshney  U. 《Computer》2002,35(12):120-121
The increasing deployment of wireless networks and the widespread popularity of handheld devices have led to numerous applications ranging from mobile banking to location-based tracking to mobile advertising. With nearly 300 million mobile users worldwide expected to be purchasing content on wireless devices by 2005, many of these emerging services would greatly benefit from infrastructure support for mobile payments. Many emerging services would greatly benefit from infrastructure support for mobile payments.  相似文献   

8.
One of the key responsibilities of any government is to communicate and disseminate safety information and warnings to the general public in case of an emergency. Traditionally, warnings are issued by the government through a broadcast approach using communication channels such as TV and radio. However this monopolistic approach is now challenged by new technologies and media capable of providing individualised warnings to personal mobile devices. Location-based emergency services and mobile alerts are becoming increasingly prevalent in the provision of emergency warnings. These new modes of emergency services have been adopted by several countries worldwide including Australia. One example is the Australian National Emergency Alert (EA) which is a telephone-based service enhanced with location-based capabilities. This paper introduces the concept of applying global satellite navigation systems such as the Japanese satellite system in the domain of emergency warning and alerting. The Japanese satellite warning system can be tailored to transmit real-time location-based emergency warnings to people's mobile devices while not being constrained by the limitations of ground-based communication technologies. A key advantage of satellite based communication is its high resilience to communication network overload and failure of ground systems and network infrastructure during a disaster. This enables people to obtain necessary information anywhere (outdoor) and anytime during times of disaster. A satellite-based warning system could also be integrated with existing warning services and be used as a complementary technology. This paper examines opportunities and challenges for using satellite navigation systems to deliver warnings and safety messages during emergencies and disasters.  相似文献   

9.
Social serendipity: mobilizing social software   总被引:4,自引:0,他引:4  
Many mobile devices incorporate low-power wireless connectivity protocols, such as Bluetooth, that can be used to identify an individual to other people nearby. We have developed an architecture that leverages this functionality in mobile phones - originally designed for communication at a distance - to connect people across the room. Serendipity is an application of the architecture. It combines the existing communications infrastructure with online introduction systems' functionality to facilitate interactions between physically proximate people through a centralized server. A new mobile-phone-based system uses Bluetooth hardware addresses and a database of user profiles to cue informal, face-to-face interactions between nearby users who don't know each other, but probably should.  相似文献   

10.
Websigns: hyperlinking physical locations to the Web   总被引:1,自引:0,他引:1  
HP researchers are developing handheld devices that combine wireless technology and ubiquitous computing to provide a transparent linkage between physical entities in the environment and resources available on the Web. First-generation mobile computing technologies typically use protocols such as WAP and i-mode to let PDAs, smart phones, and other wireless devices with Web browsers access the Internet, thereby freeing users from the shackles of their desktops. We believe, in addition, users would benefit from having access to devices that combine the advantages of wireless technology and ubiquitous computing to provide a transparent linkage between the physical world around them and the resources available on the Web. We are developing devices that augment users' reality with Web services related to the physical objects they see  相似文献   

11.
位置隐私保护技术研究进展   总被引:5,自引:3,他引:2  
移动通信和移动定位技术的快速发展促进了一个新的研究领域--基于位置的服务(LBSs).基于位置的数据的隐私保护已经成为基于位置的服务中的研究热点.在基于位置的服务被广泛使用的今天,位置隐私保护的重要性已经被充分地认识到.位置k-匿名[25] 是最早提出的用来保护位置隐私的技术,它是在用于保护关系数据记录隐私的k-匿名方法的基础上扩展而来的.目前,关于基于位置服务中的隐私保护的研究已经取得了一定的成果.然而,在基于位置的服务中,服务的质量与用户的隐私是一对矛盾,如何更好地平衡两者之间的矛盾也是研究的重点.另一方面,对用户的隐私进行保护而引发的一系列问题将对服务器处理能力提出新的挑战,例如如何对服务器端的不确定数据进行高效的查询处理等.因此,基于位置服务中的位置隐私保护不仅仅只关注如何保护用户的隐私,还需要关注隐私保护带来的一系列相关问题.本文初步讨论了当前位置隐私保护的方法及有待解决的问题.  相似文献   

12.
Nowadays the classic web paradigms are being subjected to changes; every day millions of users around the world use their Smartphones to access web applications from anywhere. The World Wide Web it is one of the biggest repositories of information in the world, and that information is stored in internet servers and repositories, but today in the real world there are many other information sources such as electronic devices with communication capabilities: smart appliances and sensor networks. The Smartphones are equipped with communication hardware elements like the Bluetooth module, which allows the Smartphone to exchange information with nearby electronic devices. Every day more and more mobile applications are being developed for native platforms that use Bluetooth’s communication module to send and receive information from different sources. Native mobile applications use the specific platform’s APIs to manage the Bluetooth communication actions (send and receive information, search for devices, etc.), however, web applications do not have technical capabilities to manage the Smartphone’s Bluetooth communication module and thereof cannot use that kind of information. The main objective of this research work is to design a novel framework that allows classic web applications to use information from nearby electronic devices. The proposed framework must be easy to use and able to be integrated with common web technologies. Developers can use this framework to include new information sources and data exchange procedures in an easy way. The new type of information can be merged with the web to develop or improve algorithms and web applications.  相似文献   

13.
《Computer Networks》1999,31(9-10):1011-1028
Wireless ATM is receiving a significant attention as a solution for wireless access. The integration of wireless access and ATM is an essential requirement for the future of telecommunications so that emerging wideband services which embody multimedia applications can be made transparently available to mobile terminals. There are many ongoing activities within the European ACTS program (Advanced Communications Technologies and Services) which are related to evolving ATM oriented wireless networks at various frequencies such as 5, 17, 40 and 60 GHz. AWACS (ATM Wireless Access Communication System) is one of these projects and addresses the feasibility of low cost, high-data-rate radio LAN systems based on ATM (both indoor and outdoor) at 19 GHz. This article overviews the AWACS project which has contributed to the definition of emerging European radio LAN standards such as ETSI BRAN HIPERLINK.  相似文献   

14.
Many localization algorithms and systems have been developed by means of wireless sensor networks for both indoor and outdoor environments. To achieve higher localization accuracy, extra hardware equipments are utilized by most of the existing localization solutions, which increase the cost and considerably limit the location-based applications. The Internet of Things (IOT) integrates many technologies, such as Internet, Zigbee, Bluetooth, infrared, WiFi, GPRS, 3G, etc., which can enable different ways to obtain the location information of various objects. Location-based service is a primary service of the IOT, while localization accuracy is a key issue. In this paper, a higher accuracy localization scheme is proposed which can effectively satisfy diverse requirements for many indoor and outdoor location services. The proposed scheme composes of two phases: (1) the partition phase, in which the target region is split into small grids; (2) the localization refinement phase, in which a higher accuracy of localization can be obtained by applying an algorithm designed in the paper. A trial system is set up to verify correctness of the proposed scheme and furthermore to illustrate its feasibility and availability. The experimental results show that the proposed scheme can improve the localization accuracy.  相似文献   

15.
Mobile cloud computing framework for a pervasive and ubiquitous environment   总被引:1,自引:1,他引:0  
The increasing use of wireless Internet and smartphone has accelerated the need for pervasive and ubiquitous computing (PUC). Smartphones stimulate growth of location-based service and mobile cloud computing. However, smartphone mobile computing poses challenges because of the limited battery capacity, constraints of wireless networks and the limitations of device. A fundamental challenge arises as a result of power-inefficiency of location awareness. The location awareness is one of smartphone’s killer applications; it runs steadily and consumes a large amount of power. Another fundamental challenge stems from the fact that smartphone mobile devices are generally less powerful than other devices. Therefore, it is necessary to offload the computation-intensive part by careful partitioning of application functions across a cloud. In this paper, we propose an energy-efficient location-based service (LBS) and mobile cloud convergence. This framework reduces the power dissipation of LBSs by substituting power-intensive sensors with the use of less-power-intensive sensors, when the smartphone is in a static state, for example, when lying idle on a table in an office. The substitution is controlled by a finite state machine with a user-movement detection strategy. We also propose a seamless connection handover mechanism between different access networks. For convenient on-site establishment, our approach is based on the end-to-end architecture between server and a smartphone that is independent of the internal architecture of current 3G cellular networks.  相似文献   

16.
These days, a pervasive computing environment is a rapidly changing trend towards increasingly always-on connected computing devices in the convergence environment. In a pervasive computing environment, there are various multimedia web services and communications for various devices in order to provide interesting and invaluable information to users. Meanwhile, providing a wide variety of the web-based multimedia services and communications may cause various security threats and abnormal behaviors. In this paper, a multimedia visualization approach for pervasive computing environment is proposed which analyzes HTTP request and response header information to detect and visualize multimedia web attacks based on the Bayesian method. We conducted a few cases’ experiment for the verification of the proposed approach in a real environment. The experimental results such as web attack detection visualization, scanning and password attack visualization, and attacker’s position tracking visualization verify the usability of the proposed approach.  相似文献   

17.
The continuing proliferation of handheld computing devices offers a new platform for mobile computing applications that could enrich our experience of the world around us. Yet many questions about realizing this vision remain open. We have been investigating these questions at the University of California, San Diego, through the ActiveCampus Project. ActiveCampus explores technologies that can enrich the learning community in the midst of these changes. It explores wireless context-aware computing as a means to enhance the "learning community" experience of a large urban university. We have tested two applications: ActiveClass supports classroom activities, such as asking questions during a lecture, and ActiveCampus Explorer supports context-aware activities, such as instant messaging and location-aware maps annotated with dynamic hyperlinked information.  相似文献   

18.
传统基于网络的位置服务系统主要是为远程用户提供查询移动对象位置的信息服务。而现有基于移动终端的位置感知服务不能满足位置上下文应用的要求.为了达到系统自动自发的上下文交互目的。需要在应用中定义一个位置检测代理来捕获移动设备的位置变化事件.生成有效的上下文信息.本文使用简单贝叶斯分类算法实现了基于无线局域网的临近位置检测代理.在室内环境中进行实验表明。该方法可根据实际需要调整位置检测的范围与准确度。具有可行性与灵活性.  相似文献   

19.
Wireless mobile services are computing applications that run on handheld wireless devices. Such applications must work within the daunting constraints of the devices, which include memory, processing power, input capabilities, and size of display. It is therefore important that mobile services take into account the user’s context, optimize resource usage, and minimize input effort imposed on the user. In this paper, we present the design and implementation of a smart agent-enabled system for personalizing wireless mobile services and advertisements for Java 2 Micro Edition (J2ME) or Java ME, and Wireless Application Protocol (WAP) enabled devices. We use software agents for context filtering because such autonomous software entities have characteristics that can benefit mobile devices and the wireless environment, and the Composite Capability/Preference Profiles (CC/PP) standard for defining profiles for user preferences and device capabilities. The system incorporates the use of artificial neural networks to adaptively and iteratively learn to select the best available service based on contextual information. The system is evaluated using practical operating scenarios, as well as empirical data and results show an 87% success rate in the selection of the best available service.  相似文献   

20.
The importance of the user perspective to the wireless information access experience cannot be understated: simply put, users will not indulge in devices that are perceived to be difficult to use and in technologies that do not offer quality infotainment – combined information and entertainment – content. In this paper, we investigate the impact that mobile devices have on the user wireless infotainment access experience in practice. To this end, we have undertaken an empirical study placed in a ‘real-world’ setting, in which participants undertook typical infotainment access tasks on three different wireless-enabled mobile devices: a laptop, a personal digital assistant and a head mounted display device. Results show that, with the exception of participants’ level of self-consciousness when using such devices in public environments, the user wireless information access experience is generally unaffected by device type. Location was shown, though, to be a significant factor when users engage in tasks such as listening to online music or navigation. Whilst the interaction between device and environment was found to influence entertainment-related tasks in our experiments, the informational ones were not affected. However, the interaction effects between device and user type was found to affect both types of tasks. Lastly, a user’s particular computing experience was shown to influence the perceived ease of wireless information access only in the case of online searching, irrespective of whether this is done for primarily informational purposes or entertainment ones.  相似文献   

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