基于TWAIN技术的图像获取应用设计

本文讨论了在图像获取设备和应用裼 一个标准通信协议（ＴＷＡＩＮ协议）。该协议一方面使设备能被更多的应用程序支持，另一方面应用不需要修改就能支持更多的设备或设备的更新。应用这种技术，我们开发了一个能方便地融合文字和图像的应用程序，取得了很好的效果。     

使用JMX和J2SE5.0安全管理Web应用程序

JMX (Java管理扩展)提供管理本地和远程应用程序、系统对象和设备等的工具。本文说明如何使用JMX(JSR160)远程管理Web应用程序。本文将解释应用程序中需要的代码,这些代码能被JMX客户端使用。同时,还演示了如何使用诸如MC4J和jmanaged等不同的客户端连接到支持JMX的应用程序。此外,还详细介绍了使用RMI协议和JNDI来保护通信层。我们先分析一个简单的Web应用程序,这个程序监视已     

移动Ad Hoc网中基于任务图应用的实现

论文提出了一个基于任务图的应用结构模型,以及它在移动adhoc网中的实现。该结构通过一个由“节点”和“边界”组成的任务图描述了一种分布式的应用。它选择能完成任务并且满足一定属性的设备来执行应用程序,同时分离出部分应用程序让网络中的其它有效设备执行。为实现上述应用,论文提出了一个执行协议并进行了实验,结果表明该协议是可行的。     

基于中央服务器模型的蓝牙多播技术

为解决蓝牙多播技术在移动智能终端应用的问题,分析蓝牙协议的特点及其通信机制,综合考虑通信设备的数量和设备间通信时间的延迟等因素,提出一个基于中央服务器的多播通信模型。通过改善蓝牙的基带层协议,打破传统蓝牙协议仅能支持7个设备的限制,实现一个可以同时支持更多设备进行通信的中央服务器设备,其对设备的调度采用的是基于活跃度的平等调度算法 EASA （equality of active scheduling algorithm）,该算法是对 RR （round Robin）调度算法的改进,以活跃度为指标,保证调度的公平性,缩短活跃度高的设备间通信时间的延迟。实验结果表明,该模型可以支持多个设备,保证通信的实时性。     

基于IP实时通信的实时出版——定购协议

IP,TCP,UDP是因特网通信的标准传输协议 ,但这些协议对于应用程序开发过于底层。用来做商业应用的高层协议 ,比如 HTTP,CORBA和 DCOM已经被开发出来 ,但是 ,许多分布实时应用程序的开发者发现他们没有提供恰当的抽象层次或关键功能。例如没有一个协议能为起决定作用的通信、对时间有感知的通告、主控制者状态通告、透明的热交换替代或服务质量控制提供支持。用标准因特网传输的出版—订购协议已经被开发出来 ,它支持分布式实时进程间通信。这个协议已被 IDA(Interface for Distributed Automation)采用。本文描述了设计要求 ,并介绍了怎样用标准 U DP/ IP在有严格时间期限要求的应用程序中实现网络质量决定传输质量、可靠的出版—订购和客户—服务器模型的消息机制。     

云桌面中USB设备重定向技术研究

随着云计算的不断发展,云桌面解决方案也日益成熟并成为典型的云计算应用案例。云桌面运用虚拟化技术,把计算资源进行池化,并通过网络为多形态的用户终端提供资源池中的应用程序或者传统PC桌面。桌面传输协议是其核心技术之一,为终端用户提供与传统PC桌面相近的使用体验。与传统物理PC机桌面相比,云桌面中对USB设备的支持尚不成熟。而USB设备凭借其即插即用、数据传输速率快等显著优势已经成为使用最广泛的计算机外设接口。云桌面用户体验的一个关键之处就是支持USB等外部设备。在云桌面中部署USB重定向之后,USB设备物理连接在客户端,而用户可以在Guest端系统上正常读写数据并操作USB设备,满足用户更多的办公需求和日常使用。文中介绍了云桌面及主流桌面传输协议,研究了USB重定向解决方案,并基于SPICE开源桌面传输协议和USBRedir技术予以实现,重点分析了USB设备虚拟化框架、虚拟多通道技术和USBRedir技术等关键原理技术,同时阐释了USB重定向在云桌面中的应用部署。     

蓝牙网络封装协议的应用及其测试

蓝牙SIG定义了蓝牙网络封装协议BNEP，该协议对上层口协议提供了类似于以太网的接口。对于IEEE802．3／Ethemet封装支持的网络协议，蓝牙网络封装均支持。BNEP协议把这些网络协议包封装起来，直接通过蓝牙I2CAP协议进行无线传输。蓝牙网络封装主要应用在蓝牙个人无线局域网(PAN)中，PAN应用是指由两个或者更多的设备形成一个特定网络，而且这些设备能通过一个网络接入点来访问远程网络。由于蓝牙SIG只是用自然语言定义了协议规范，不同的实现者由于理解的差异可能会导致不同的结果，这可能会影响到产品的互通性，因此对协议的测试是至关重要的。BNEP协议的测试是蓝牙一致性测试，这种测试是完全自动化的。     

USB2.0控制器EZ-USB-FX2的性能特点及其数据传输实现

USB2.0协议不仅支持低速(1.5Mbps)和全速(12Mbps)设备,而且支持高速设备(480Mbps),是新一代的通用串行总线标准。该文对代表业界尖端水准的USB2.0控制器EZ-USB-FX2的性能特点作了介绍,并以EP2端口数据传输为例,详细讨论了设备端固件及主机应用程序的实现方法。     

基于分布式数据库的OLTP应用程序开发平台

文中设计了一个为开发在线事务处理应用程序提供直接支持的开发平台，在这个平台上创建的事务处理监视器（ＴＰｍｏｎｉｔｏｒ）为建立、运行和管理事务处理应用程序确立了一个基本框架，这个平台提供了事务型ＲＰＣ（远程过程调用），并使用ＯＳＩ－ＴＰ协议中所定义的两阶段提交协议来保证事务的ＡＣＩＤ特性。     

支持指定QoS的多媒体通信软件平台

由应用程序指定通信服务质量是网络多媒体应用对通信技术提出的主要要求。本文基于新一代ＩＰ协议ＩＰＶ６，资源预留协议ＲＳＶＰ，Ｎａｔｉｖｅ ＡＴＭ和ＷｉｎＳｏｃｋ２，在传统网络和ＡＴＭ网络上提出一个支持由应用程序指定ＱｏＳ的多媒体通信软件平台。     

Stateful session handoff for mobile WWW

This paper proposes a web session handoff system that can hand over not only stateless but also stateful sessions between homogenous and heterogeneous user devices to enable uninterrupted and seamless web access. The proposed system adopts a proxy-based approach and an optional client-assisted scheme in order to track and hand over session information. In the proposed system, a session is registered at a User Agent Proxy (UAP) and then tracked by the UAP so that the session can be handed over from one device via the UAP to another device. In addition to session information tracked by a UAP, the UAP can hand over more comprehensive session information by using the client-assisted scheme. Compared with client-based approaches, our design has several advantages, such as less modification to user devices, practicability, and fault tolerance. We have implemented a UAP on a PC and client programs for both PC and PDA. The implementation can successfully hand over between PC and PDA a stateful session for online shopping applications.     

位置隐私研究综述

近年来随着传感器和无线移动设备的飞速发展,随时随地获得个人位置成为可能。一方面,促进了基于位置服务的飞速发展,另一方面,个人位置隐私泄露的问题引起人们的广泛关注。由于移动环境中位置信息的特殊性,造成无法直接利用现有的关系数据库隐私保护技术。文章分析了位置隐私保护中存在的挑战问题,从系统结构、位置匿名技术和查询处理技术三方面归纳总结了现有的研究工作,并指出了未来的研究方向。     

An Internetware Based Approach to Building Web Page Integration Applications for Mobile Devices

Mobile devices are more and more popular in recent years. As a result, there''re huge requests of mobile applications, especially those integrated with multiple information. However, on one hand, most of the mobile applications at present just contain some certain kinds of information and they cannot adapt to the rapid change of users'' requirements, either. On the other hand, to build these applications, it''s usually time consuming and there are not enough resource components with programmable interfaces. In this paper, we propose an approach based on Internerware to building web page integration applications for mobile device. We introduce a framework that provides abundant internet-programmable interfaces, a flexible integration mechanism to meet the users'' rapid changing requirements and a reliable mechanism that guarantees the quality of the referred resources effectively. With this framework, we can rapidly build an application that integrates all the information according to users'' requirement.     

Selected challenges in computer networking

The convergence of computing and networking is nowhere more evident than in the phenomenal growth of the World Wide Web. In another sense, though, computer networking is being pulled in two opposite directions. On the one hand, the Web's popularity and growth has been fueled largely by desktop applications consuming bandwidth-intensive images and video. On the other hand, thin-client computers are becoming more commonly used as edge-of-network devices, often connected by wireless technology. There is also an increasing mismatch between fiber-optic transmission bandwidths and computer speeds, pushing computing further away from the network core. Are there ways to close, or at least manage, this growing schism-whether through novel hardware solutions or the programmability of network infrastructures? Can we better integrate these edge-of-network devices and make them full-fledged network participants? The paper discusses programmable network challenges     

嵌入式Linux系统中USB的应用

随着USB设备在嵌入式系统中应用的日益广泛,对基于嵌入式系统的USB设备的开发需求也越发的迫切。本文首先对嵌入式系统和USB设备的发展进行了分析,然后从硬件结构及软件驱动等两方面论述了USB设备在嵌入式Linux系统中的应用。     

嵌入式Linux系统中USB的应用

随着USB设备在嵌入式系统中应用的日益广泛,对基于嵌入式系统的USB设备的开发需求也越发的迫切。本文首先对嵌入式系统和USB设备的发展进行了分析,然后从硬件结构及软件驱动等两方面论述了USB设备在嵌入式Linux系统中的应用。     

Adapting web pages using graph partitioning algorithms for user-centric multi-device web browsing

In the era of ubiquitous computing, applications are emerging to benefit from using devices of different users and different capabilities together. This paper focuses on user-centric web browsing using multiple devices, where content of a web page is partitioned, adapted and allocated to devices in the vicinity. We contribute two novel web page partitioning algorithms. They differ from existing approaches by allowing for both, automatic and semi-automatic partitioning. On the one hand, this provides good automatic, web page independent results by utilizing sophisticated structural pre- and postprocessing of the web page. On the other hand, these results can be improved by considering additional semantic information provided through user-generated web page annotations. We further present a performance evaluation of our algorithms. Moreover, we contribute the results of a user study. These clearly show that (1) our algorithms provide good automatic results and (2) the application of user-centric, annotation-based semantic information leads to a significantly higher user satisfaction.     

Provision and maintenance of presence and immersion in hand‐held virtual reality through motion based interaction

Hand‐held devices are also becoming computationally more powerful and being equipped with special sensors and non‐traditional displays for diverse applications aside from just making phone calls. As such, it raises the question of whether realizing virtual reality, providing a minimum level of immersion and presence, might be possible on a hand‐held device capable of only relatively “small” display. In this paper, we propose that motion based interaction can widen the perceived field of view (FOV) more than the actual physical FOV, and in turn, increase the sense of presence and immersion up to a level comparable to that of a desktop or projection display based VR systems. We have implemented a prototype hand‐held VR platform and conducted two experiments to verify our hypothesis. Our experimental study has revealed that when a motion based interaction was used, the FOV perceived by the user for the small hand held device was significantly greater than (around 50%) the actual. Other larger display platforms using the conventional button or mouse/keyboard interface did not exhibit such a phenomenon. In addition, the level of user felt presence in the hand‐held platform was higher than or comparable to those in VR platforms with larger displays. We hypothesize that this phenomenon is related to and analogous to the way the human vision system compensates for differences in acuity resolution in the eye/retina through the saccadic activity. The paper demonstrates the distinct possibility of realizing reasonable virtual reality even with devices with a small visual FOV and limited processing power. Copyright © 2010 John Wiley & Sons, Ltd.     

Activity recognition with hand-worn magnetic sensors

Activity recognition is a key technology for realizing ambient assisted living applications such as care of the elderly and home automation. This paper proposes a new activity recognition method that employs hand-worn magnetic sensors to recognize a broad range of activities ranging from simple activities that involve hand movements such as walking and running to the use of portable electrical devices such as cell phones and cameras. We sense magnetic fields emitted by electrical devices and the earth with hand-worn sensors, and recognize what a user is doing or which electrical device the user is employing. We frequently use a large number of different electrical devices in our daily lives, and so we can estimate high-level daily activities by recognizing their use. Our approach permits us to recognize a range extending from low-level simple activities to high-level activities that relate to the hands without the need to attach any sensors to the electrical devices.     

Understanding Computer Users With Tetraplegia: Survey of Assistive Technology Users

An online survey in the form of a questionnaire was conducted to obtain the opinion of computer users with tetraplegia on their current computer interfaces and to assess desirable applications for future independent control using assistive devices. The survey included questions related to information about the respondents' injury/disease, everyday activities and social life, electronic devices and computer programs, evaluation of computer interfaces, and desirable applications for assistive devices. The survey was distributed via tetraplegia associations, magazines, and Internet forums mainly in Denmark and Sweden, but also through other European and American associations. Thirty-one completed questionnaires were collected from individuals with spinal cord injury and other neuromuscular diseases that resulted in tetraplegia. Respondents evaluated gaze and head trackers; speech recognition systems; chin, mouth, and hand joysticks; sip and puff interfaces; and typing sticks. Most interfaces were evaluated in a range from neutral to good. Users expressed a desire for applications to independently control wheelchairs, television sets, doors, and windows. This is, as far as is known, the first study that compares a wide range of current commercial computer interfaces that have been used as part of the users' everyday lives. The answers are useful for designing and developing alternative computer interfaces and assistive devices and for computer-interface users to identify a computer-interface fitting more to his or her needs.