Context‐Aware Active Services in Ubiquitous Computing Environments

With the advent of ubiquitous computing environments, it has become increasingly important for applications to take full advantage of contextual information, such as the user's location, to offer greater services to the user without any explicit requests. In this paper, we propose context‐aware active services based on context‐aware middleware for URC systems (CAMUS). The CAMUS is a middleware that provides context‐aware applications with a development and execution methodology. Accordingly, the applications based on CAMUS respond in a timely fashion to contextual information. This paper presents the system architecture of CAMUS and illustrates the content recommendation and control service agents with the properties, operations, and tasks for context‐aware active services. To evaluate CAMUS, we apply the proposed active services to a TV application domain. We implement and experiment with a TV content recommendation service agent, a control service agent, and TV tasks based on CAMUS. The implemented content recommendation service agent divides the user's preferences into common and specific models to apply other recommendations and applications easily, including the TV content recommendations.     

Centaurus: An Infrastructure for Service Management in Ubiquitous Computing Environments

In the near future, we will see dramatic changes in computing and networking hardware. A large number of devices (e.g., phones, PDAs, even small household appliances) will become computationally enabled. Micro/nano sensors will be widely embedded in most engineered artifacts, from the clothes we wear to the roads we drive on. All of these devices will be (wirelessly) networked using Bluetooth, IEEE 802.15 or IEEE 802.11 for short range connectivity creating pervasive environments. In this age where a large number of wirelessly networked appliances and devices are becoming commonplace, there is a necessity for providing a standard interface to them that is easily accessible by any user. This paper outlines the design of Centaurus, an infrastructure for presenting services to heterogeneous mobile clients in a physical space via some short range wireless links. The infrastructure is communication medium independent; we have implemented the system over Bluetooth, CDPD and Infrared, three well-known wireless technologies. All the components in our model use a language based on Extensible Markup Language (XML) for communication, giving the system a uniform and easily adaptable interface. Centaurus defines a uniform infrastructure for heterogeneous services, both hardware and software, to be made available to diverse mobile users within a confined space.     

Supporting Service Discovery,Querying and Interaction in Ubiquitous Computing Environments

In this paper, we contend that ubiquitous computing environments will be highly heterogeneous, service rich domains. Moreover, future applications will consequently be required to interact with multiple, specialised service location and interaction protocols simultaneously. We argue that existing service discovery techniques do not provide sufficient support to address the challenges of building applications targeted to these emerging environments.This paper makes a number of contributions. Firstly, using a set of short ubiquitous computing scenarios we identify several key limitations of existing service discovery approaches that reduce their ability to support ubiquitous computing applications. Secondly, we present a detailed analysis of requirements for providing effective support in this domain. Thirdly, we provide the design of a simple extensible meta-service discovery architecture that uses database techniques to unify service discovery protocols and addresses several of our key requirements. Lastly, we examine the lessons learnt through the development of a prototype implementation of our architecture.     

Optimal 3-Coverage with Minimum Separation Requirements for Ubiquitous Computing Environments

Sensors have been increasingly used for many ubiquitous computing applications such as asset location monitoring, visual surveillance, and human motion tracking. In such applications, it is important to place sensors such that every point of the target area can be sensed by more than one sensor. Especially, many practical applications require 3-coverage for triangulation, 3D hull building, and etc. Also, in order to extract meaningful information from the data sensed by multiple sensors, those sensors need to be placed not too close to each other—minimum separation requirement. To address the 3-coverage problem with the minimum separation requirement, our recent work  (Kim et al. 2008) proposes two heuristic methods, so called, overlaying method and TRE-based method, which complement each other depending on the minimum separation requirement. For these two methods, we also provide mathematical analysis that can clearly guide us when to use the TRE-based method and when to use the overlaying method and also how many sensors are required. To make it self-contained, in this paper, we first revisit the two heuristic methods. Then, as an extension, we present an ILP-based optimal solution targeting for grid coverage. With this ILP-based optimal solution, we investigate how much close the two heuristic methods are to the optimal solution. Finally, this paper discusses the impacts of the proposed methods on real-deployed systems using two example sensor systems. To the best of our knowledge, this is the first work that systematically addresses the 3-coverage problem with the minimum separation requirement.     

From Ubiquitous Computing to Ubiquitous Intelligence

If computers could be as commonplace as the written word, our everyday world would be transformed. That was the vision, announced over a decade ago, of the computer visionary Mark Weiser. In Weiser's world computers would be ubiquitous and we would interact with them almost subconsciously. This vision is currently developing, but has still some way to go. Yet Weiser's vision can be extended further, with intelligence embedded in objects ranging from mechanical components to tins. This paper outlines a future which embraces Weiser's vision but goes beyond it to a world of such intelligent devices interacting autonomously, for the benefit of people but often without human intervention. Opportunities exist, in particular for those who develop the new applications and the complex systems which support them. For the general public the greatest fearwhich needs to be allayed is a loss of privacy.     

A Semantic Service Discovery Network for Large‐Scale Ubiquitous Computing Environments

This paper presents an efficient semantic service discovery scheme called UbiSearch for a large‐scale ubiquitous computing environment. A semantic service discovery network in the semantic vector space is proposed where services that are semantically close to each other are mapped to nearby positions so that the similar services are registered in a cluster of resolvers. Using this mapping technique, the search space for a query is efficiently confined within a minimized cluster region while maintaining high accuracy in comparison to the centralized scheme. The proposed semantic service discovery network provides a number of novel features to evenly distribute service indexes to the resolvers and reduce the number of resolvers to visit. Our simulation study shows that UbiSearch provides good semantic searchability as compared to the centralized indexing system. At the same time, it supports scalable semantic queries with low communication overhead, balanced load distribution among resolvers for service registration and query processing, and personalized semantic matching.     

Enabling Attribute Delegation in Ubiquitous Environments

When delegation is implemented using the attribute certificates in a Privilege Management Infrastructure (PMI), it is possible to reach a considerable level of distributed functionality. However, the approach is not flexible enough for the requirements of ubiquitous environments. The PMI can become a too complex solution for devices such as smartphones and PDAs, where resources are limited. In this work we present an approach to solve the previous limitations by defining a second class of attributes, called domain attributes, which are managed directly by users and are not right under the scope of the PMI, thus providing a light solution for constrained devices. However, we relate the two classes of attributes are related by defining a simple ontology. While domain attribute credentials are defined using SAML notation, global attributes are defined using X.509 certificates. For this reason, we additionally introduce XSAML so that both kinds of credentials are integrated. We also introduce the concept of Attribute Federation which is responsible for supporting domain attributes and the corresponding ontology.     

泛在计算与泛在网

1泛在计算的提出和发展笔者在2006年8月撰文《亚太主要RFID应用国家的发展特点》一文中,提及了下述事实和观点:日本接受了美国Xerox公司CEO Marx Weiser氏早在台式电脑刚刚开始普及的1986年就提出的观点Nomadic Issues in Ubiquitous Computing。这句话虽然可以直译为计算技术无处不在,但是其内容远远超过上述简单的中文解释。     

On Teaching Ubiquitous Computing

As industry demand for ubiquitous computing applications continues to increase, universities are beginning to offer related courses. A graduate-level ubicomp course at Finland's ?bo Akademi University taught both system design and research advancements to meet the students' career goals. The instructor gained experiences and learned lessons that can help other educators in the field.     

普适计算中的隐私保护

普适计算(Ubiquitous Computing)改变了人们的计算和联系方式,为研究者带来了方便与高效。但为了避免普适系统最终成为一个分布式监督系统,需要在系统设计的最初阶段就认真考虑用户的隐私问题。为此,这里将普适计算中的隐私问题划分为物理层、链路层和应用层这三层来解决,为系统设计者提供了灵活的隐私保护方案。     

An Ontology-driven Model for Digital Forensics Investigations of Computer Incidents under the Ubiquitous Computing Environments

Innumerable firms are extensively integrating state-of-the-art ICT to boost the competitiveness of the organizations in all aspects. Simultaneously, the unprecedented availability of UC networks and mobile devices are exponentially growing. Unfortunately, based on the current voluminous computer crime incidents, the ICT deployments under UC infrastructures might jeopardize the organizations if they ignore the imminent necessity of DF in their homogeneous/heterogeneous ISs. Most enterprises are dearth of vigilance concerning the above issues although they might be aware that the salient and stringent computer crimes are capable of devastating the company’s intangible assets silently. Vandalism of intellectual property or conducting industrial espionage for the valuable assets via trustworthy UC networks becomes an approaching menace. Hence, the DF plays an essential role in the information security arena. Demonstrably, there is no one DF suite can encompass all aspects or purposes due to the dynamic diversities of computer crimes in their natures. Interchangeably utilizing various DF tools is a decent approach to find the causes for the associate computer crimes and prevents the related information security incidents from occurring. At last, a DF scenario review utilizing the proposed ontology-driven model with respect to the UC environment was conducted and demonstrated.     

普适环境中的动态更新模型

致力于普适计算下的动态更新的研究,首先分析了普适计算下动态更新的场景,针对普适环境的动态性,我们提出了区别于传统更新方式的路径更新;通过分析集中式更新模型的局限性,提出了适合普适环境的分布式更新模型;最后使用类型与效果系统为更新模型做形式化分析.     

Low-Cost Identifiers for Ubiquitous Computing

Any device we want to connect to a global network, e.g. Internet, should have a unique global identifier. However, the size of this identifier can be an unacceptable overhead for devices with limited resources (sensors, toys, disposable devices, micro-robots, etc.), because conventional protocols use full addresses to transmit, process, and store the data required for routing. The usual solution for such devices is to limit the address space to 1 or 2 bytes, but this sacrifices the global unicity of the identifiers. The proposal presented in this article enables devices with limited resources to use reduced addresses that globally identify hosts. We propose the use of abbreviated addresses for routing. We have developed a new protocol named ADSR that takes advantage of these new addresses. This protocol is a modified version of DSR based on the use of abbreviated addresses. The abbreviation procedure can lead to two different nodes having the same address, which we will term collision. ADSR allows rather than avoids collisions. The foundations of this protocol, and some results of an implementation are also presented in this article.     

Assessing Level of Ubiquitous Computing Services for Ubiquitous Business Design

We are entering into a new era of enterprise computing that is characterized by an emphasis on broadband convergence, knowledge sharing, and calm services. Some people refer to this as the "ubiquitous network" business model because its focus is on a high degree of connectivity between a company and its customers, suppliers, and channel partners. Moreover, immediate access to ideas, goods, and services will be of greater value than the traditional model of permanent and ponderous possession. This paper illustrates how ubiquitous computing technology can be combined with legacy computer-based information systems, along with thoughts on relevant issues of ubiquitous commerce. We also propose a model for how to assess levels of ubiquitous computing services.     

移动泛在环境中的分布式终端技术

未来的无线接入技术的异构性使得终端向着可重构的方向发展,而个人周边的智能设备逐渐增多,成为未来移动业务不可忽视的一部分,两者的结合将引出一种新的重构方式,通过个人周边智能设备的协同工作,构成一个分布式的终端系统,不仅能够适应不同接入网的变化,而且能更充分地利用个人周边智能设备的业务能力,为用户提供更佳业务体验。     

A Strategic Grid for Implementing Ubiquitous Computing

This letter offers a general framework representing the most effective strategies for implementing ubiquitous computing, given different levels of organizational information system capacity and business needs. The strategic grid offered here identifies promising movements which may potentially have a significant effect on the future development of ubiquitous computing.     

Smart Identification Frameworks for Ubiquitous Computing Applications

We present our results of the conceptual design and the implementation of ubiquitous computing applications using smart identification technologies. First, we describe such technologies and their potential application areas, then give an overview of some of the applications we have developed. Based on the experience we have gained from developing these systems, we point out design concepts that we have found useful for structuring and implementing such applications. Building upon these concepts, we have created two frameworks based on Jini (i.e., distributed Java objects) and Web Services to support the development of ubiquitous computing applications that make use of smart identification technology. We describe our prototype frameworks, discuss the underlying concepts and present some lessons learned.     

云计算技术在泛在网络中的应用前景分析

泛在应用的广泛性与数据海量化等特征需要一种高效的信息处理手段来提供技术保证。本文首先分析了泛在网络及其应用平台对各类计算与网络资源的初步要求,对当前云计算技术的分布式处理能力进行了评估,并对云计算在未来泛在应用的研究方向提供了参考建议。同时,提出了一种基于云计算技术的泛在应用体系架构,为云计算技术的研究提供了全新的应用领域。