Adapting Web content to mobile user agents

In this article, we describe an adaptation proxy we developed as a part of a Kontti research project at VTT Information Technology that lets mobile users access Web content that's not directly targeted to mobile user agents. More and more content is now available on the Internet, and there's a growing need for mobile users to be able to access it. Thus the authors describe the adaptation proxy, which lets mobile users access Web content that's not directly targeted to user agents of mobile devices. The adaptation proxy can adapt Extensible Hypertext Markup Language (XHTML) documents into XHTML mobile profile (XHTML MP) and Wireless Markup Language (WML), and can perform media adaptation. At the system's core is an adaptation framework to which new source and target XML languages can be introduced with relatively little effort.     

Mobile access to real-time information—the case of autonomous stock brokering

When services providing real-time information are accessible from mobile devices, functionality is often restricted and no adaptation of the user interface to the mobile device is attempted. Mobile access to real-time information requires designs for multi-device access and automated facilities for the adaptation of user interfaces. We present TapBroker, a push update service that provides mobile and stationary access to information on autonomous agents trading stocks. TapBroker is developed for the Ubiquitous Interactor system and is accessible from Java Swing user interfaces and Web user interfaces on desktop computers, and from a Java Awt user interface on mobile phones. New user interfaces can easily be added without changes in the service logic.     

基于Web注释的移动客户端自适应机制的研究

由于各种移动设备在计算能力上有所区别,目前没有一种较好的机制能够使Web内容根据移动设备的性能转换成不同页面大小。该文给出一种通过注释Web页面的方法来实现自适应移动设备,在不改动原有网站的基础上根据移动设备的计算能力生成合适的Web内容。与其它方法相比,该方法在设备自适应性、用户订制和转换速度等方面有较大的提高。     

Seamless video access for mobile devices by content-aware utility-based adaptation

Today’s Internet multimedia services are characterized by heterogeneous networks, a wide range of terminals, diverse user preferences, and varying natural environment conditions. Heterogeneity of terminals, networks, and user preferences impose nontrivial challenges to the Internet multimedia services for providing seamless multimedia access particularly for mobile devices (e.g., laptops, tablet PCs, PDAs, mobile phones, etc.). Thus, it is essential that advanced multimedia technologies are developed to deal with these challenges. One of these technologies is video adaptation, which has gained significant importance with its main objective of enabling seamless access to video contents available over the Internet. Adaptation decision taking, which can be considered as the “brain” of video adaptation, assists video adaptation to achieve this objective. Scalable Video Coding (SVC) offers flexibility for video adaptation through providing a comprehensive set of scalability parameters (i.e., temporal, spatial, and quality) for producing scalable video streams. Deciding the best combination of scalability parameters to adapt a scalable video stream while satisfying a set of constraints (e.g., device specifics, network bandwidth, etc.) poses challenges for the existing adaptation services to enable seamless video access. To ease such challenges, an adaptation decision taking technique employing a utility-based approach to decide on the most adequate scalability parameters for adaptation operations is developed. A Utility Function (UF), which models the relationships among the scalability parameters and weights specifying the relative importance of these parameters considering video content characteristics (i.e., motion activity and structural feature), is proposed to assist the developed technique. In order to perform the developed adaptation decision taking technique, a video adaptation framework is also proposed in this paper. The adaptation experiments performed using the proposed framework prove the effectiveness of the framework to provide an important step towards enabling seamless video access for mobile devices to enhance viewing experience of users.     

Multimedia layout adaptation through grammatical specifications

Online multimedia presentations, such as news, need to be constantly updated. Increasing demands are also being made for accessing online multimedia documents from mobile devices such as PDAs. There is an urgent need for a sound but practical formalism that supports automatic adaptation to the change of media content, display environments, and user intention. This paper presents a visual language approach to the layout adaptation of multimedia objects. The underlying theory of our approach is a context-sensitive graph grammar formalism enriched with facilities for spatial representation and specification. The paper focuses on the issues and techniques for size adaptation and style adaptation in response to the change of device requirements and user interactions.Published online: 2 February 2005 Correspondence to: Kang Zhang     

Can Convenience and Effectiveness Converge in Mobile Web? A Critique of the State-of-the-Art Adaptation Techniques for Web Navigation on Mobile Handheld Devices

Proliferation of mobile handheld devices and the significant advancement of wireless technologies and infrastructures have become a strong driving force of many mobile applications, including ubiquitous web information access through those devices. Despite the tremendous flexibility, accessibility, and convenience, rendering and navigating Web content on handheld devices suffer from significant usability problems attributable to their physical constraints, especially the small screen size, restricted interaction mechanisms, and low memory. Therefore, improving the effectiveness of web content navigation on those devices is crucial and has attracted increasing attention from both academics and industry. One of the promising solutions is adaptation, which focuses on the content restructuring, rearranging, and visualization. This article attempts to provide a comprehensive review of the state-of-the-art approaches to web adaptation for mobile handheld devices. The study not only categorizes, synthesizes, and compares the pros and cons of major adaptation methods but also discusses the observed problems in research methodology adopted in related studies and highlights future research directions. The article provides an important road map to the researchers and practitioners in this field.     

XMobile: A MB-UID environment for semi-automatic generation of adaptive applications for mobile devices

Ubiquitous Computing promises seamless access to information anytime, anywhere with different and heterogeneous devices. This kind of environment imposes new challenges to software development. For example, information and user interface should be adapted according to contextual characteristics such as user, environment, and access device. In case of device adaptation, the development challenge is related to the heterogeneity of the devices, which requires software engineers to create different versions for each type of device and every platform. This paper proposes a MB-UID (model-based user interface development) approach for semi-automatic generation of adaptive applications for mobile devices. An environment, called XMobile, offers a device-independent user interface framework and a code generation tool for providing fast development of multi-platform and adaptive applications according to device and platform features. A case study is also presented to illustrate how the environment can be used for constructing an application for heterogeneous devices with different network connectivity modes.     

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.     

A Flexible Content Adaptation System Using a Rule-Based Approach

Content adaptation is an important technique for mobile devices. Existing content adaptation systems have been developed with specific adaptation goals. In this paper, we present an extensible content adaptation system, Xadaptor. We take a rule-based approach to facilitate extensible, systematic, and adaptive content adaptation. It integrates adaptation mechanisms for various content types and organizes them into the rule base. Rules are invoked based on the individual client information. We classify HTML page objects into structure, content, and pointer objects. Existing content adaptation techniques mainly focus on content objects and do not consider adaptation for structure and pointer objects. In Xadaptor, novel adaptation techniques for the structure object HTML table have been developed. We use fuzzy logic to model the adaptation quality and guide the adaptation decision. To demonstrate the feasibility of our approach, we have implemented a prototype system. Experimental studies show that Xadaptor is capable of on-the-fly content adaptation and is easily extensible     

Improving device-aware Web services and their mobile clients through an aspect-oriented,model-driven approach

ContextMobile devices have become an essential element in our daily lives, even for connecting to the Internet. Consequently, Web services have become extremely important when offering services through the Internet. However, current Web services are very inflexible as regards their invocation from different types of device, especially if we consider the need for them to be adaptable when being invoked from mobile devices.ObjectiveIn this paper, we provide an approach for the creation of flexible Web services which can be invoked transparently from different device types and which return subsequent responses, as well as providing the client’s adaptation as a result of the particular device characteristics and end-user preferences in a completely decoupled way.MethodAspect-Oriented Programming and model-driven development have been used to reduce both the impact of service and client code adaptation for multiple devices as well as to facilitate the developer’s task.ResultsA model-driven methodology can be followed from system models to code, providing the Web service developer with the option of marking which services should be adapted to mobile devices in the UML models, and obtaining the decoupled adaptation code automatically from the models.ConclusionWe can conclude that the approach presented in this paper provides us with the possibility of following the development of mobile-aware Web services in an integrated platform, benefiting from the use of aspect-oriented techniques not only for maintaining device-related code completely decoupled from the main functionality one, but also allowing a modularized non-intrusive adaptation of mobile clients to the specific device characteristics as well as to final user preferences.     

Toward interactive mobile synchronous learning environment with context-awareness service

Mobile synchronous learning is a new challenge in the e-learning domain. While popular mobile communication devices, such as cell phones, cannot directly accommodate traditional synchronous content due to the major limitation of display size, other constraints also restrict convenient interactions while using mobile devices in a synchronous learning environment. These problems have motivated the authors of this study to design a context-awareness synchronous learning system and to develop a corresponding pedagogical framework. Different than existing synchronous learning strategies, the proposed system enhances the feedback mechanism and implements an enhanced model for achieving mobile interaction in a synchronous learning environment. The enhanced model is named Interactive Service Module, which enables interactions between teachers and students via short message delivery. In the proposed synchronous learning environment, different kinds of learning devices are used to access the same source of synchronous content simultaneously. To accommodate the diversity of devices, several content styles have been developed and an appropriate style can be selected to a learner via a decision mechanism. This mechanism is based on fuzzy weighted average technique to measure the average computational power for each device. Finally, questionnaires were used to evaluate the usability of the proposed synchronous learning environment, and the results indicate that our system can facilitate synchronous learning by enabling students to access lessons conveniently and efficiently from a wide variety of locations, using common mobile communication devices.     

Mobile information access in the real world: A story of three wireless devices

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.     

A personal mobile DRM manager for smartphones

In this paper we report on our experience in building the experimental Personal Digital Rights Manager for Motorola smartphones, an industry first.Digital Rights Management allows producers or owners of digital content to control the manner in which the content is consumed. This may range from simply preventing duplication to finer access policies such as restricting who can use the content, on what devices, and for how long. In most commercial DRM systems, the average end user plays the role of content consumer, using DRM protected content made available by a service. Here we present a personal digital rights system for mobile devices where the end user has the ability to place DRM protection and controls on his or her own personal content.We designed the personal DRM system to allow users of a mobile device to transparently define controls and generate licenses on custom content and securely transfer them to other mobile devices. A user is able to define and restrict the intended audience and ensure expiration of the content as desired. Compatible devices automatically detect each other and exchange credentials. The personal DRM system on each device safely enforces the content usage rules and also handles moving licenses between devices while preventing leakage of content. We implemented a prototype of our system on Motorola E680i smartphones.     

A secure and traceable E-DRM system based on mobile device

In recent years, intellectual property violation events have caused enterprise to respect digital content protection. Illegal copying digital content abuses become a serious problem. Because the mobile devices are more portable and individualized than personal computers, anyone can access the network resources at anytime from anywhere. However, valuable digital contents without proper protection make the content vulnerable to unauthorized copying, modification and re-distribution, causing revenue losses to service providers. Thus, constructing an effective Digital Right Management (DRM) system has become an important issue.On the basis of the mobile device, we propose an efficient digital rights management protocol. We apply symmetrical cryptosystem, asymmetrical cryptosystem, digital signature and one-way hash function mechanisms in our scheme. To overcome the computing resource weakness problem of mobile devices, we also integrate digital certificate, hardware information and one time password mechanisms such that the security, persistent protection, integrity, authentication, track usage of DRM work, changeable access right, integration and portability issues will be assured. In this way, the mobile user can access the digital content securely in the enterprise via authorization mechanism.     

基于普适计算的虚拟场景自适应网络发布研究

针对移动设备访问三维虚拟场景受到网络带宽和终端计算能力的制约,使得在线利用虚拟现实进行移动学习效率不高,基于此提出了基于普适计算的自适应优化选择技术.对三维实体进行本体语义描述,建立相应的优化模型.在此基础上通过WURFL对手持移动设备进行采样获取设备参数,对参数进行分析从而建立普适规则,利用普适计算进行自适应优化选择.测试结果表明,经过自适应选择后手持移动设备荻取三维虚拟场景资源的速度和效率得到明显提高.     

User-centric universal multimedia access in home networks

Much research is currently being conducted towards Universal Multimedia Access, aiming at removing barriers that arise when multimedia content is to be consumed with more and more heterogeneous devices and over diverse networks. We argue that users should be put at the center of the research work to enable user-centric multimedia access. In this paper we present the requirements for a user-centric multimedia access system in a networked home environment. These requirements are easy access to available content repositories, context awareness, content adaptation and session migration. After showing the limits of state-of-the-art technologies, we present the architecture of a system which allows unified access to the home network content, automatically delivered to rendering devices close to the user, adapted according to the rendering device constraints, and which is also capable of session mobility.     

Automatic adaptation of mobile applications to different user devices using modular mobile agents

Wearable, handheld, and embedded or standalone intelligent devices are becoming quite common and can support a diverse range of applications. In order to simplify development of applications which can adapt to a variety of mobile devices, we propose an adaptation framework which includes three techniques: follow‐me, context‐aware adaptation, and remote control scheme. For the first, we construct a personal agent capable of carrying its owner's applications. Second, we design a personal agent capable of carrying applications with an adaptable hierarchical structure. Then, applications can be adapted approximately to the context of evices by using an attribute‐based component decision algorithm. Finally, to achieve a remote control scheme, we distribute the computational load of applications on the resource‐restricted mobile devices. An application is divided into two parts that can be executed on a user device and a server separately. In short, this framework facilitates the development of widespread applications for ubiquitous computing environments. Furthermore, it enables the applications to follow their owners and automatically adapt to different devices. Copyright © 2005 John Wiley & Sons, Ltd.     

Customizing Graphics for Tiny Displays of Mobile Devices

Advances in mobile devices and wireless telecommunication infrastructure already provide mobile users with access to online information sources and services. Compared to the PC world, however, mobile access is still quite restricted, especially with regard to the display of graphical representations, such as images, drawings, diagrams, maps and logos. Since graphical representations are increasingly used in the World Wide Web for the purpose of information presentation, the adaptation of graphics for tiny displays is a challenge that should not be neglected. The current contribution discusses several transformation approaches which might be employed to accomplish this adaptation task.     

Mytilene E-guide: a multiplatform mobile application tourist guide exemplar

This paper introduces an approach of enhancing the tourism experience by incorporating a tool that adopts a “web-to-mobile” model into tourism websites that allows for the adaptation of personalized tourism web content to be transferred to a mobile application hosted at users’ mobile device. These applications upon installation to mobile devices allow for browsing of adapted multimedia content with no requirement for constant network connection. Furthermore so we convey the development experiences of a multiplatform mobile tourist guide aimed at producing a personalized mobile guide application used in both an online and offline modes offering services to tourists such as a personal profiling-based recommendation system, a commenting system and location-based services. This paper focuses on the design, implementation and usability case study of a Multi-Platform Tourist Guide system for the Municipal Council of Mytilene, Greece.     

Using RSS feeds for effective mobile web browsing

While mobile phones are becoming more popular, wireless communication vendors and device manufacturers are seeking new applications for their products. Access to the large corpus of Internet information is a very prominent field. However, the technical limitations of mobile devices pose many challenges. Browsing the Internet using a mobile phone is a large scientific and cultural challenge. Web content must be adapted before it can be accessed by a mobile browser. This work presents a new methodology that uses Really Simple Syndication (RSS) feeds for the adaptation of web content for use in mobile phones. This methodology is based on concrete design guidelines and supports different viewing modes. The mobile tool provided using the RSS feeds is evaluated based on user-centered evaluation and the results are presented.