A lightweight and distributed middleware to provide presence awareness in mobile ubiquitous systems

Several researchers have identified the need to count on presence awareness in ubiquitous systems that support mobile activities, particularly when these systems are used to perform loosely-coupled mobile work. In such a work style, mobile users conduct face-to-face on-demand interactions, therefore counting on awareness information about the position and availability of potential collaborators becomes mandatory for these applications. Most proposed solutions that provide user presence awareness involve centralized components, have reusability limitations, or simply address a part of that service. This article presents a lightweight and fully distributed middleware named Moware, which allows developers to embed presence awareness services in mobile ubiquitous systems in a simple way. The article also describes the Moware architecture, its main components and strategies used to deal with several aspects of the presence awareness support. These design strategies can be reused by software designers to provide presence awareness capabilities into middleware and specific software applications. Moware services were embedded in a mobile ubiquitous system that supports inspectors during the construction inspection process. The preliminary results indicate that the middleware was easy to use for developers, and its services were useful for the end-users.     

面向普适环境的上下文感知中间件研究

针对普适环境下上下文感知计算需求,引入广义模型化理论,建立了一种面向通用环境资源的上下文信息数据模型;在此基础上,提出了上下文感知中间件体系框架,并详细阐述了其构件化的实施方案。该中间件平台的上下文获取层能够封装各类感知器捕获的资源信息,中间处理层负责信息的管理、推理和聚合,基于门面模式的上下文访问层提供同步和异步相结合的上下文信息统一访问入口。通过实验测试了平台的时间损耗,表明该中间件可提供通用的上下文感知服务且具有较好的系统性能。     

面向开放移动网络环境的新一代中间件技术研究

结合现有网络计算环境的特点,对适用于开放、移动网络环境的新一代中间件技术进行了研究。在分析今天网络环境关键特征的基础上,提出了新一代中间件系统需要满足的技术需求;从所针对的问题角度对新一代中间件系统面临的主要挑战进行了详细的讨论,包括上下文感知、环境自适应、开放式协作、服务发现和普适互操作等,并给出了一些解决方案。     

基于活动的情境感知系统交互设计

情境感知是移动和普适计算研究中一个重要的组成部分。现有研究大多从技术的角度进行情境感知系统的设计和实现。由于缺少对人的情境感知机制的认识,导致系统的情境感知行为和人的期望之间存在着很大的差距。在活动理论和人的情境感知理论的基础上,提出了基于活动的情境感知模型,用于描述特定活动中人的情境感知过程;并在该模型的基础上,提出了基于活动的情境感知系统交互设计方法。通过基于活动的情境感知购物助手的交互设计过程,验证了基于活动的情境感知模型在情境感知系统交互设计中的应用。     

Situation Awareness Data Fusion Method Based on Library Events

Microelectronic technology and communication technology are developed in deep manner; the computing mode has been transferred from traditional computer-centered to human centered pervasive. So, the concept of Internet of things (IoT) is gradually put forward, which allows people to access information about their surroundings on demand through different terminals. The library is the major public space for human to read and learn. How to provide a more comfortable library environment to better meet people’s learning requirements is a place where the Internet of things plays its role. The purpose of this paper is to solve the difference between the data fusion of library environment and the data fusion of other environments by the method of data fusion oriented to library. This paper presents a general technical framework of situational awareness for smart library system which includes a data fusion middleware. It can process data and inform the upper module of the changed library environment after deploying the smart library system in a library, including data collection and processing, how to judge whether events are triggered, how the system reacts, and the acquisition and update of user preferences. This paper presents a situational awareness recommendation method based on an effective data fusion model and algorithm for library after conducting experimental in service of library, which give more accurate of book recommendation than traditional method and good learning service environment of library for readers.     

MobiPADS: a reflective middleware for context-aware mobile computing

Traditionally, middleware technologies, such as CORBA, Java RMI, and Microsoft's DCOM, have provided a set of distributed computing services that essentially abstract the underlying network services to a monolithic "black box." In a mobile operating environment, the fundamental assumption of middleware abstracting a unified distributed service for all types of applications operating over a static network infrastructure is no longer valid. In particular, mobile applications are not able to leverage the benefits of adaptive computing to optimize its computation based on current contextual situations. In this paper, we introduce the Mobile Platform for Actively Deployable Service (MobiPADS) system. MobiPADS is designed to support context-aware processing by providing an executing platform to enable active service deployment and reconfiguration of the service composition in response to environments of varying contexts. Unlike most mobile middleware, MobiPADS supports dynamic adaptation at both the middleware and application layers to provide flexible configuration of resources to optimize the operations of mobile applications. Within the MobiPADS system, services (known as mobilets) are configured as chained service objects to provide augmented services to the underlying mobile applications so as to alleviate the adverse conditions of a wireless environment.     

MIMOSA: context-aware adaptation for ubiquitous web access

The ubiquitous computing scenario is characterized by heterogeneity of devices used to access services, and by frequent changes in the user’s context. Hence, adaptation according to the user’s context and the used devices is necessary to allow mobile users to efficiently exploit Internet-based services. In this paper, we present a distributed framework, named MIMOSA, that couples a middleware for context-awareness with an intermediary-based architecture for content adaptation. MIMOSA provides an effective and efficient solution for the adaptation of Internet services on the basis of a comprehensive notion of context, by means of techniques for aggregating context data from distributed sources, deriving complex contextual situations from raw sensor data, evaluating adaptation policies, and solving possible conflicts. The middleware allows programmers to modularly build complex adaptive services starting from simple ones, and includes tools for assisting the user in declaring her preferences, as well as mechanisms for detecting incorrect system behaviors due to a wrong choice of adaptation policies. The effectiveness and efficiency of MIMOSA are shown through the development of a prototype adaptive service, and by extensive experimental evaluations.     

面向普适计算的动态自适应中间件模型

为了提高普适计算系统的开发效率, 设计了一个基于OSGi框架的动态普适计算中间件模型. 该中间件模型以OSGi框架为基础, 建立移动管理器管理用户和服务的移动, 利用上下文管理器来管理上下文, 动态调整自己的行为, 支持上下文感知应用. 通过标准的接口实现各种异构普适设备间的互操作性. 实验结果表明该中间件能够满足通用普适计算环境的要求, 对于普适计算系统的开发具有一定的借鉴意义.     

普适计算环境下基于中间件的上下文质量管理框架研究

随着信息技术的快速发展,分布式计算技术逐渐向普适计算技术演化,从而达到信息空间和物理空间融合的最终目标,为用户提供普适的智能化服务。为了达到这个目标,一个主要的困难就是如何有效地连续监测、才甫获与解释环境相关的上下文信息来确保精确的上下文感知性。很多研究者已先后投身于上下文感知的普适应用的研究工作中,但大多数往往直接针对原始上下文进行处理,没有考虑上下文质量(QoC)的影响。因此,提出了一种基于中间件的上下文质量管理框架,即通过上下文的质量门阂管理、重复与不一致的上下文丢弃等不同层次的控制机制,为上下文感知服务和应用用户提供有效而可靠的上下文服务。     

Multimodal interaction with a wearable augmented reality system

An augmented reality system enhances a mobile user's situational awareness and provides new visualization functionality. The custom-built multimodal interface provides access to information encountered in urban environments. In this article, we detail our experiences with various input devices and modalities and discuss their advantages and drawbacks in the context of interaction tasks in mobile computing. We show how we integrated the input channels to use the modalities beneficially and how this enhances the interface's overall usability.     

An energy-efficient object discovery protocol for context-sensitive middleware for ubiquitous computing

Many ubiquitous computing applications may be context-sensitive due to the ambient environments, mobile devices, and other detectable factors. A context-sensitive middleware provides the necessary support to context-sensitive application objects to participate in spontaneous and ad hoc communications with other applications in remote devices whenever suitable contexts exist. A context-sensitive middleware can provide this support effectively if its communication subsystem, such as an Object Request Broker (ORB), can properly discover other objects in devices. This capability is usually known as object discovery protocol. An energy-efficient object discovery protocol is needed to help prolong a device's battery life because many devices in ubiquitous computing environments are battery-powered and, thus, have limited energy sources. An energy-efficient object discovery protocol, RKS, for context-sensitive middleware for ubiquitous computing is presented. RKS reduces energy consumption by reducing the amount of information that needs to be sent to remote devices to discover objects. A novel feature of RKS is that it advertises its server-objects' availability only when it detects that these servers can be activated in the current context and when it finds that the neighbor devices have some potential clients that are willing to discover objects. Analytical comparisons of the energy-consumptions are given between RKS and two other protocols for object discovery in context-sensitive middleware. Furthermore, our experimental results, based on the implementations of these protocols and RKS on a context-sensitive middleware test bed, confirm our analytical results in that the RKS conserves more energy than the other two.     

Mobile agent middleware for mobile computing

Mobile computing requires an advanced infrastructure that integrates suitable support protocols, mechanisms, and tools. This mobility middleware should dynamically reallocate and trace mobile users and terminals and permit communication and coordination of mobile entities. In addition, open and untrusted environments must overcome system heterogeneity and grant the appropriate security level. Solutions to these issues require compliance with standards to interoperate with different systems and legacy components and a reliable security infrastructure based on standard cryptographic mechanisms and tools. Many proposals suggest using mobile agent technology middleware to address these issues. A mobile agent moves entities in execution together with code and achieved state, making it possible to upgrade distributed computing environments without suspending service. We propose three mobile computing services: user virtual environment (UVE), mobile virtual terminal (MVT), and virtual resource management (VRM). UVE provides users with a uniform view of their working environments independent of current locations and specific terminals. MVT extends traditional terminal mobility by preserving the terminal execution state for restoration at new locations, including active processes and subscribed services. VRM permits mobile users and terminals to maintain access to resources and services by automatically requalifying the bindings and moving specific resources or services to permit load balancing and replication     

A new model for context-aware transactions in mobile services

With the ubiquity of handheld devices (such as smart phones and PDAs) and the availability of a wide range of mobile services (such as mobile banking, road traffic updates, and weather forecast), people can nowadays access information and conduct online transactions virtually anywhere and anytime. In such flexible, dynamic but less reliable environment, transaction management technology is believed to provide service reliability and data consistency. Indeed, in mobile and ubiquitous environments where devices as well as services can seamlessly join and leave the ubiquitous network; transaction management can be very helpful during the recovery of services from failure. Current transaction models and commit protocols do not take into account context information. However, in mobile environments, it is imperative to consider context information in the commit of a transaction—i.e., a transaction can be successfully completed if it meets the required context. In this paper, we propose a new model for context-aware transactions and their performance management in mobile environments. Unlike conventional transactions, context-aware transactions adapt to the required context. By context, we mean the service’s context as well as the users’ context that includes users’ needs and preferences. This paper designs and develops the proposed transaction model and evaluates its performance in terms of time and message complexities as well as transaction’s throughput.     

基于情境感知技术的智慧城市服务系统研究

随着城市规模越来越复杂,全国各级政府都在进行城市物联网和信息化建设,目前虽然搭建了互联骨干网和部署了大量的传感器,收集了众多的城市行为数据,但落后的信息管理模式难以体现信息价值,将信息体现在服务提升之中,造成信息资源的极大浪费。因此,将情境感知技术引入到智慧城市服务的应用之中,构建了一个基于情境感知的城市服务系统,并通过情境信息采集、情境信息推理和服务配置模型等关键技术,实时感知城市内的情境需求,从而提供智能化的业务服务组合。最后通过一社区智慧街道管理系统来验证本文所设计的系统效果。     

A middleware architecture for privacy protection

The issue of user privacy is constantly in spotlight since an ever increasing number of online services collects and processes personal information from users, in the context of personalized service provision. In fact, recent advances in mobile communications, location and sensing technologies and data processing are boosting the deployment of context-aware personalized services and the creation of smart environments; but at the same time, they pose a serious risk on individuals’ privacy rights. Although technology makes the collection of data easy, its protection against abuse is left to data protection legislation. However, the privacy requirements, other than being general and abstract terms to be regarded as legislature issues, should be brought down in technological reality and carefully accounted for in devising technical solutions. In order to limit the disclosure and avoid the misuse of personal data, this paper discusses an architectural proposal for a middleware system that will enforce protection of user privacy through technical means. The proposed architecture mediates between the users, the service providers and the law, constituting a middleware shield for individuals’ personal data.     

Smart Ubiquitous Networks for future telecommunication environments

In this article, future communication environments have been derived from the analysis of impacts of information communication technology and social service aspects. From the concepts of “Smart Ubiquitous Networks (SUN)” as a short-term realization of Future Networks in ITU-T, this article presents frameworks of the SUN with context awareness and smart resource management. As challenges, we propose methodologies and operational processes to support context awareness and new fine granularity of traffic for smart resource management. Finally we illustrate a use case of SUN considering a smart city to show how SUN capabilities contribute to build smart and ubiquitous communication environments.     

移动协同感知研究综述

移动感知网在军事、工业、医疗、交通、商业上运用极其广泛.为了进一步提高移动感知网的性能,更好地协同节点的移动感知行为,本文提出了移动协同感知技术.首先介绍了国内外近年来有关移动协同感知技术的发展情况和关键技术,包括移动协同感知模型、移动协同感知中间件、移动协同感知相关技术,然后概括归纳了技术特点,最后总结了移动协同感知技术的研究意义和发展趋势.     

A middleware to integrate robots,simple devices and everyday objects into an ambient ecology

The fields of ambient intelligence, distributed robotics and wireless sensor networks are converging toward a common vision, in which ubiquitous sensing and acting devices cooperate to provide useful services in the home. These devices can range from sophisticated mobile robots to simple sensor nodes and even simpler tagged everyday objects. In this vision, a milkbox left on the table after the user has left the home could ask the service of a mobile robot to be placed back in the refrigerator. A missing ingredient to realize this vision is a mechanism that enables the communication and interoperation among such highly heterogeneous entities. In this paper, we propose such a mechanism in the form of a middleware able to integrate robots, tiny devices and augmented everyday objects into one and the same system. The key moves to cope with heterogeneity are: the definition of a tiny, compatible version of the middleware, that can run on small devices; and the concept of object proxy, used to make everyday object accessible within the middleware. We describe the concepts and implementation of our middleware, and show a number of experiments that illustrate its performance.     

普适计算服务匹配技术研究

在普适计算环境下需要根据用户的需求提供合适的服务,这需要对用户请求的服务和环境提供的服务进行服务的匹配.而目前使用的基于语法的服务匹配和基于语义的服务匹配都不能很好地适应普适计算环境的高效、资源约束和上下文感知的要求.通过分析普适计算环境下主要的基于语法的和基于语义的服务匹配技术,给出普适计算环境下在高效、资源约束和上下文感知的特殊要求下服务匹配的解决方案,并就面向服务组合的服务匹配进行了分析.