Architecture layers and engineering approach for agent-based system

It is necessary to support user-centric service provision paradigm in distributed, dynamic and complex computing environment. Software agent technology is considered as one of the technologies suitable to adopt such computing environment. Many researchers have emphasized on agent-based system development, but, many agent-based systems are designed and constructed in ad hoc. In particular, they do not enough consider system organization and performance aspects. More systematic engineering approach of agent-based system is required. We propose the layered architecture and engineering approach for agent-based system design. We devise the layers necessary to design agent-based system, and methods to engineer each layer. Also we show that the devised approach can be used to design agent-based system and analyze system features. The layered architecture and engineering approach of agent-based system proposed in this paper support that engineer designs efficient agent-based system.     

Multiagent framework for lean manufacturing

We have developed the manufacturing agent-based emulation system as an open framework for design and analysis of discrete manufacturing systems. MABES currently supports the transition from traditional to lean manufacturing in two major functions: analysis of alternative agent-based scheduling and control approaches that can be implemented across the extended enterprise; and real-time collaboration of design teams during manufacturing line design and analysis stages. MABES bases its support for these functions on two system paradigms: distributed agents and synchronous collaboration     

A method and advisor tool for multimedia user interface design

This paper describes a multimedia user interface design method and a design assistant tool which supports the method. The method covers specification of user requirements and information architecture, selection of appropriate media to represent the information content, design for directing attention to important information and interaction design to enhance user engagement. Guidelines for media selection and design for attractiveness, i.e. usability and user experience, are given. The method was evaluated in a case study design of a crowd control simulation training system, which demonstrated the method was usable and gave good solutions against an expert gold standard design. The tool provides advice on media selection and attention effects that match specification of the information content expressed as information types and communication goals. A usability evaluation was carried out to measure the usefulness and effectiveness of the tool in comparison to the method, and the results showed that the tool has a positive impact on multimedia design.     

A component- and message-based architectural style for GUI software

While a large fraction of application code is devoted to graphical user interface (GUI) functions, support for reuse in this domain has largely been confined to the creation of GUI toolkits (“widgets”). We present a novel architectural style directed at supporting larger grain reuse and flexible system composition. Moreover, the style supports design of distributed, concurrent applications. Asynchronous notification messages and asynchronous request messages are the sole basis for intercomponent communication. A key aspect of the style is that components are not built with any dependencies on what typically would be considered lower-level components, such as user interface toolkits. Indeed, all components are oblivious to the existence of any components to which notification messages are sent. While our focus has been on applications involving graphical user interfaces, the style has the potential for broader applicability. Several trial applications using the style are described     

A usability study of multimodal input in an augmented reality environment

In this paper, we describe a user study evaluating the usability of an augmented reality (AR) multimodal interface (MMI). We have developed an AR MMI that combines free-hand gesture and speech input in a natural way using a multimodal fusion architecture. We describe the system architecture and present a study exploring the usability of the AR MMI compared with speech-only and 3D-hand-gesture-only interaction conditions. The interface was used in an AR application for selecting 3D virtual objects and changing their shape and color. For each interface condition, we measured task completion time, the number of user and system errors, and user satisfactions. We found that the MMI was more usable than the gesture-only interface conditions, and users felt that the MMI was more satisfying to use than the speech-only interface conditions; however, it was neither more effective nor more efficient than the speech-only interface. We discuss the implications of this research for designing AR MMI and outline directions for future work. The findings could also be used to help develop MMIs for a wider range of AR applications, for example, in AR navigation tasks, mobile AR interfaces, or AR game applications.     

Agent-Based Design Model of Adaptive Distributed Systems

A next generation distributed system is expected to adapt to various changes of both the users' requirements and the operational conditions of environment where the distributed system operates. The aim of our research is to establish a new design model of an adaptive distributed system (ADS) to deal with various changes occurred in the system environment. In this paper, we propose an agent-based architecture of ADS, based on the agent-based computing paradigm. Then, we implement a prototype of the ADS with respect to videoconferencing applications and also evaluate the adaptive functions of the ADS realized on the basis of the proposed architecture.     

Dynamically reconfigurable vision-based user interfaces

We describe a system that supports practical, vision-based user interfaces, addressing the issues of a usable interaction paradigm, support for application developers, and support for application deployment in real-world environments. Interfaces are defined as configurations of predefined interactive widgets that can be moved from one surface to another. Complex interfaces can be dynamically reconfigured, changing both form and location on the fly, because the functional definition of the interface is decoupled from the specification of its location in the environment. We illustrate the power of such an architecture in the context of projected interactive displays.Published online: 13 July 2004     

On designing an unaided authentication service with threat detection and leakage control for defeating opportunistic adversaries

Unaided authentication services provide the flexibility to login without being dependent on any additional device. The power of recording attack resilient unaided authentication services (RARUAS) is undeniable as, in some aspects, they are even capable of offering better security than the biometric based authentication systems. However, high login complexity of these RARUAS makes them far from usable in practice. The adopted information leakage control strategies have often been identified as the primary cause behind such high login complexities. Though recent proposals havemade some significant efforts in designing a usable RARUAS by reducing its login complexity, most of them have failed to achieve the desired usability standard. In this paper, we have introduced a new notion of controlling the information leakage rate. By maintaining a good security standard, the introduced idea helps to reduce the login complexity of our proposed mechanism − named as Textual-Graphical Password-based Mechanism or TGPM, by a significant extent. Along with resisting the recording attack, TGPM also achieves a remarkable property of threat detection. To the best of our knowledge, TGPM is the first RARUAS, which can both prevent and detect the activities of the opportunistic recording attackers who can record the complete login activity of a genuine user for a few login sessions. Our study reveals that TGPM assures much higher session resiliency compared to the existing authentication services, having the same or even higher login complexities. Moreover, TGPM stores the password information in a distributed way and thus restricts the adversaries to learn the complete secret from a single compromised server. A thorough theoretical analysis has been performed to prove the strength of our proposal from both the security and usability perspectives. We have also conducted an experimental study to support the theoretical argument made on the usability standard of TGPM.     

Component-based tailorability: Enabling highly flexible software applications

Component technologies are perceived as an important means to keep software architectures flexible. Flexibility offered by component technologies typically addresses software developers at design time. However, the design of software which should support social systems, such as work groups or communities, also demands ‘use-time’, or technically spoken, ‘run-time’ flexibility. In this paper, we summarize a decade of research efforts on component-based approaches to flexibilize groupware applications at run-time. We address the user as a ‘casual programmer’ who develops and individualizes software for his work context. To deal with the challenges of run-time flexibility, we developed a design approach which covers three levels: software architecture, user interface, and collaboration support. With regard to the software architecture, a component model, called FlexiBeans, has been developed. The FreEvolve platform serves as an environment in which component-based applications can be tailored at run-time. Additionally, we have developed three different types of graphical user interfaces, enabling users to tailor their applications by recomposing components. To enable collaborative tailoring activities, we have integrated functions that allow sharing component structures among users. We also present different types of support techniques which are integrated into the user interface in order to enable users’ individual and collaborative tailoring activities. We conclude by elaborating on the notion of ‘software infrastructure’ which offers a holistic approach to support design activities of professional and non-professional programmers.     

ARREST: From work practices to redesign for usability

In this paper we discuss the redesign of a support management system deployed in a small and medium sized enterprise (SME) in the UK. The original system was not fulfilling its needs as it had not captured work practices in a way that was recognizable to the users. The advantages of the redesign included: improved usefulness; improved efficiency and productivity; reduced learning time; improved usability; and increased acceptance among users. The system is used to support complex and distributed cooperative activities taking place in an SME. We evaluated the current system and analysed work practices using a user-centred design and evaluation philosophy. In this paper we discuss how user needs are incorporated into the enhanced design of the support management system. The user-centred design techniques used in this research include interviews, questionnaires, observations and user tests. We present comparative evaluation results that show significant improvement in performance of user tasks using the redesigned support management system. The contribution of this paper is the presentation of a case study to show how a user-centred design and evaluation philosophy can lead to better requirements capture resulting in systems that more accurately capture the users’ conceptual models.     

Design and Evaluation of a Touch-Based Personalizable In-Vehicle User Interface

There is a trend of personalizable products at the same time as there is a substantial growth of functions in the automobile user interface. A research through design approach was used to explore the potential of a personalizable vehicle user interface to improve traffic safety as well as user experience by offering a product that is tailored to the user’s own needs and preferences. A prototype was evaluated by 20 participants with several methods: interviews, Computer System Usability Questionnaire, Microsoft product reaction cards, and driving simulator measures. The prototype was experienced positively (flexible, easy to use, and usable), few usability issues were found, no negative effects on driving performance were found, and it was assumed that it could improve traffic safety. All participants stated that they would want to use such a system in their own cars.     

ManufAg: a multi-agent-system framework for production control of complex manufacturing systems

In this paper, we present a framework for the implementation of multi-agent-systems for production control of complex manufacturing systems. We present the results of a requirement analysis for production control systems for complex manufacturing systems; then we describe the framework design criteria. Our framework supports the inclusion of distributed hierarchical decision-making schemes into the production control. Furthermore, in order to increase the coordination abilities of multi-agent-systems, we follow the decision-making and staff agent architecture suggested in the PROSA reference architecture. We indicate the usage of the framework for designing and implementing an agent-based production control system for semiconductor manufacturing processes in a case study.     

Matching large schemas: Approaches and evaluation

Current schema matching approaches still have to improve for large and complex Schemas. The large search space increases the likelihood for false matches as well as execution times. Further difficulties for Schema matching are posed by the high expressive power and versatility of modern schema languages, in particular user-defined types and classes, component reuse capabilities, and support for distributed schemas and namespaces. To better assist the user in matching complex schemas, we have developed a new generic schema matching tool, COMA++, providing a library of individual matchers and a flexible infrastructure to combine the matchers and refine their results. Different match strategies can be applied including a new scalable approach to identify context-dependent correspondences between schemas with shared elements and a fragment-based match approach which decomposes a large match task into smaller tasks. We conducted a comprehensive evaluation of the match strategies using large e-Business standard schemas. Besides providing helpful insights for future match implementations, the evaluation demonstrated the practicability of our system for matching large schemas.     

Designing Motion Gesture Interfaces in Mobile Phones for Blind People

Despite the existence of advanced functions in smartphones, most blind people are still using old-fashioned phones with familiar layouts and dependence on tactile buttons. Smartphones support accessibility features including vibration, speech and sound feedback, and screen readers. However, these features are only intended to provide feedback to user commands or input. It is still a challenge for blind people to discover functions on the screen and to input the commands. Although voice commands are supported in smartphones, these commands are difficult for a system to recognize in noisy environments. At the same time, smartphones are integrated with sophisticated motion sensors, and motion gestures with device tilt have been gaining attention for eyes-free input. We believe that these motion gesture interactions offer more efficient access to smartphone functions for blind people. However, most blind people are not smartphone users and they are aware of neither the affordances available in smartphones nor the potential for interaction through motion gestures. To investigate the most usable gestures for blind people, we conducted a user-defined study with 13 blind participants. Using the gesture set and design heuristics from the user study, we implemented motion gesture based interfaces with speech and vibration feedback for browsing phone books and making a call. We then conducted a second study to investigate the usability of the motion gesture interface and user experiences using the system. The findings indicated that motion gesture interfaces are more efficient than traditional button interfaces. Through the study results, we provided implications for designing smartphone interfaces.     

一个基于CORBA的图形用户界面体系结构及实例

随着网络计算技术的发展,软件的结构变为表示／处理／数据库分离的三级模式。表示与处理的分离导致了用户界面与应用计算间的通信成为开发交互式系统图形用户界面的关键。本文为分布式交互图形应用的开发提供了一个基于公用对象需求代理结构ＣＯＲＢＡ的用户界面体系结构,ＣＯＲＢＡ是为分布式对象系统中间件制定的一个互操作标准。在这个结构中,一些被称为代理的面向对象交互式图形构件被设计用来为图形的表示与交互提供有效的解     

Service-Oriented Policy Management for Web-Application Frameworks

Policy Based Management technologies represent a potentially important tool in the management of user services provided by web application frameworks. Current policy management systems are, however, a poor fit for the domain due to their lack of support for decentralised management in open environments. The Community Based Policy Management System is a policy framework designed to facilitate management of services in domains where relationships are highly dynamic and flexible, where policy specification is distributed and may use multiple languages, and where management decision-making is shared between communities of users and service providers. This article describes the CBPMS schema and architecture and uses an example to show how it provides flexible, dynamic and extensible policy based management capabilities to the providers of user-services on the web.     

Schema mediation for large-scale semantic data sharing

Intuitively, data management and data integration tools should be well suited for exchanging information in a semantically meaningful way. Unfortunately, they suffer from two significant problems: they typically require a common and comprehensive schema design before they can be used to store or share information, and they are difficult to extend because schema evolution is heavyweight and may break backward compatibility. As a result, many large-scale data sharing tasks are more easily facilitated by non-database-oriented tools that have little support for semantics.The goal of the peer data management system (PDMS) is to address this need: we propose the use of a decentralized, easily extensible data management architecture in which any user can contribute new data, schema information, or even mappings between other peers schemas. PDMSs represent a natural step beyond data integration systems, replacing their single logical schema with an interlinked collection of semantic mappings between peers individual schemas.This paper considers the problem of schema mediation in a PDMS. Our first contribution is a flexible language for mediating between peer schemas that extends known data integration formalisms to our more complex architecture. We precisely characterize the complexity of query answering for our language. Next, we describe a reformulation algorithm for our language that generalizes both global-as-view and local-as-view query answering algorithms. Then we describe several methods for optimizing the reformulation algorithm and an initial set of experiments studying its performance. Finally, we define and consider several global problems in managing semantic mappings in a PDMS.Received: 16 December 2002, Accepted: 14 April 2003, Published online: 12 December 2003Edited by: V. Atluri     

Recommending multimedia web services in a multi-device environment

In the last years, the Web community has shown a broad interest in Web services that handle multimedia contents. To improve the usability of these services different tools have been proposed in the literature, and in this context agent-based recommender systems appear to be a promising solution. However, the recommender systems presented in the past do not take into account, in their recommendation algorithms, the effect of the device exploited by the user, while it is clear that the same user shows a different behavior in the presence of different devices. This paper tries to give a contribution in this setting, in order to match more accurately user preferences and interests. In particular, a new agent-based system is proposed, whose architecture allows to compute recommendations of multimedia Web services, considering the effect of the currently exploited device. Some experimental results confirm the high quality of the recommendations generated by the proposed approach.     

The role played by perceived usability,satisfaction and consumer trust on website loyalty

We performed a study to determine the influence that perceived usability has on the user's loyalty to websites that they visit. The results of the empirical analysis confirmed that the trust of the user increases when the user perceived that the system was usable and that there was a consequent increase in the degree of website loyalty. In the same way, greater usability was found to have a positive influence on user satisfaction, and this also generated greater website loyalty. Finally, it was found that user trust was partially dependent on the degree of consumer website satisfaction.