Agent-based service composition has provided a promising computing paradigm for the automatic web service composition. In this paper, a formal service agent model is proposed, which integrates the web service and software agent technologies into one cohesive entity. Based on the service agent model, a distributed planning algorithm for web service composition called DPAWSC is presented. DPAWSC formalizes web service composition into a graph search problem according to the dependence relations among service agents. The key to DPAWSC is that the alternative solution with smaller length has higher priority to be searched than one with larger length. DPAWSC is based on the distributed decision making of the autonomous service agents and addresses the distributed nature of web service composition. We evaluate the algorithm by simulation experiments and the results demonstrate that DPAWSC is effective for its ability to produce the high quality solution at a low cost of communications.

Mobile phones are truly personal devices loaded with personal data such as photos, contacts, and call history. Yet it is often necessary or desirable to share our phones with others. This is especially true as mobile phones are integrating features conventionally provided by other dedicated devices, from MP3 players to games consoles. Yet existing phones assume a single user and provide little protection for private data and applications when a phone is shared. That is, when we lend our phones to others, we give away complete access. In this work, we present xShare, a protection solution to address this problem. xShare allows phone owners to rapidly specify what they want to share and place the phone into a restricted mode where only the data and applications intended for sharing can be accessed. We first present two formative user studies and derive the design requirements of xShare. We then offer the design of xShare based on file-level access control. We describe the implementation of xShare on Windows Mobile and report a comprehensive evaluation, including performance measurements, usability, and a one-month field trial.

An agent-based Web service workflow model is presented in this paper to facilitate the autonomic Web service composition, which contains three layers. The top is the user layer which represents the service requirements as goal workflow, the bottom service layer denotes the distributed Web services, and the middle is the agent layer. Each service agent in the agent layer abstracts the features of a group of actual operations with similar functions as operation template and models the process of using operation templates to achieve a certain goal as plan. The proposed model has great flexibility and extensibility and provides the guidance for the development of Web service integration tools.

Loaded with personal data, e.g. photos, contacts, and call history, mobile phones are truly personal devices. Yet it is often necessary or desirable to share our phones with others. This is especially true as mobile phones are integrating features conventionally provided by other dedicated devices, from MP3 players to games consoles. Unfortunately, when we lend our phones to others, we give away complete access because existing phones assume a single user and provide little protection for private data and applications. In this work, we present xShare, a protection solution to address this problem. xShare allows phone owners to rapidly specify what they want to share and place the phone into a restricted mode where only the data and applications intended for sharing can be accessed.

Mobile computing environments pose two challenging problems for the design and configuration of mobile services: constant changes of computation contexts and resource limitation of mobile devices. This paper presents a dynamic software configuration approach implemented by using different design paradigms during execution time. After analyzing the features of these paradigms, we propose the selection rules of design paradigms under different contexts, which are used to dynamically reconfigure mobile services to adapt to environmental changes and meet the users' requirements. The rules make the automatic or semi-automatic software configuration possible. To conserve resources, we present an optimal software partitioning algorithm based on network flow theory to optimize the design paradigms. Finally, a case study shows the flexibility and effectiveness of our approach

One of the challenging problems that Web service technology faces is the ability to rapidly locate useful on-line services based on their capabilities. With the increasing popularity of Web services, a wide variety of services are offered that can satisfy the functional requirements of a special task, therefore there is need for mediation infrastructures able to support humans or agents in the eventual selection of appropriate services. To address this problem, a fuzzy multi-attribute decision making algorithm for Web services selection based on quality of service is proposed, which can select the most appropriate one with the highest degree of membership belonging to the positive ideal solution. The experimental results indicate that the fuzzy multi-attribute decision making algorithm proposed in this paper outperforms the random and round robin selection policies

A traditional application with only one design paradigm can not well adapt to the constant variations of contexts and user preferences in pervasive computing. In this paper, we argue that a pervasive computing application should support multiple design paradigms and present an approach to dynamically selecting the most appropriate paradigm at runtime according to environmental changes. Based on analyzing the characteristics of adaptive software architecture, this paper presents the general paradigm selection rules which can be combined with the specific context to automatically or semi-automatically create the applicable software (re)configuration strategies. For mobile components paradigm, a novel heuristic software partitioning algorithm is proposed to reasonably allocate a pervasive computing application among machines for resource conservation. Finally, we discuss a case study that demonstrates the flexibility and effectiveness of our approach

The rapid popularity of wireless networks and portable devices spurs mobile users to access various information services. Service provision in ubiquitous computing has become a challenging issue. In this paper, we present a user-centric service provision model (TJCSPM). UCSPM is designed to support user-oriented quality of service (QoS) evaluation and dynamic service delivery, according to various contexts such as device capability, network status and user preference, etc. Unlike most service provision middleware, UCSPM can provide appropriate services to mobile users, which are not only suitable for being delivered to resource-limited environments, but also with a high degree of satisfaction of users. We have developed a prototype of context-aware expo assistant application to demonstrate the effectiveness of UCSPM.

This paper presents an operation-based exchange mechanism for interoperability in heterogeneous CAD collaboration. The mechanism different from STEP-based exchange mechanism facilitates the engineers to exchange design information in distributed environment with shared semantic operations instead of model data, and to synchronously or asynchronously reconstruct the design process by executing the semantic operations in native CAD system. The proposed architecture based on this mechanism is developed to integrate traditional CAD systems and multimedia tools, and to provide essential collaborative support functions. The operation-based collaborative design system is applicable to many interactive design activities such as remote design review and online collaborative design.

Distributed applications operating in pervasive computing environment should have abilities to cope with the high heterogeneity and variability of this environment. In a high abstract level, the dynamic software architecture can be used to provide the flexibility and adaptation for the applications by modifying the structure of software, such as adding, removing, replacing components, in the execution time. Besides, mobile codes technologies have provided ability to move around for components. However, software architecture supporting component migration has not been deeply studied. In this paper, an adaptable software architecture for pervasive computing is introduced. We revisit software architecture, and describe its elements related to mobility, especially components and connectors, in formal forms. Due to the components’ correlation, the migration relationships between two components are proposed and discussed in detail. As an example, multiple notable design paradigms are expressed in a unified way by using our mobile component approach, which shows the effectiveness and generality of our model.

Yan-Nong Huang et al. (1998) define a SQL-like language to specify organizational policies (or constraints) in workflow systems. Three types of policies are studied including qualification, requirements and substitution policies. However, they can't handle complex role resolution, such as separation of roles and binding of roles, and several exception situations, such as role delegation and role unavailable. Furthermore, from the perspective of project-oriented workflow, a project and its subprojects can be under the charge of teams (or virtual teams). The teams should satisfy the role resolution of the projects managed by the team. To support the above requirements, based on the team-enabled organization model, (1) we extend the policy language defined by Yan-Nong Huang et al. to support role resolution in project-oriented workflow, (2) provide its modeling and enforcement mechanism, and (3) propose rules to guarantee the correctness and optimization of the policy repository.

According to supply chain's junction views and its lifecycle, a model called P/spl I.bar/DROCE is provided as an integrated supply chain workflow model that is proved to support concurrent engineering effectively. It consists of five sub-models: business P/spl I.bar/DROCE process model (P), order model (D), resource model (R), organization model (O), cost and evaluation model (CE). The P/spl I.bar/DROCE model is different from other modes as it can be integrated by the workflow system. Based on P/spl I.bar/DROCE model and business rules, a supply chain workflow management system is introduced. As Petri net theory lacks the ability of expressing P/spl I.bar/DROCE as behaviors and mobility, we put forward a method using /spl pi/ calculus to describe the business P/spl I.bar/DROCE processes behaviors and communications. At last, it is given the formal verification of the supply chain workflow management system.

Patterns are widely used to capture design decisions and rationale of software, but they could also be used to document and guide the development of software process. This paper proposes a framework called hierarchical process patterns (HPP), which includes three types of pattern: lifecycle pattern, activity pattern, and workflow pattern. This division makes it easier to tailor and refine software processes in a stepwise way. To describe the workflow of process pattern and relationships between roles and artifacts of realized activity and those of sub activities, this paper presents a set of representation mechanism and defines role inheritance diagram and artifact decomposition diagram. To support variable number of same category of activities, this paper introduce parameterized compound activity in workflow pattern. Finally, this paper gives an example to illustrate how to apply the framework in SPDM, which is a process-centered software engineering environment.

Cased-based reasoning (CRB) is a methodology that follows mankind's problem solving strategy. Most traditional CBR systems are built in a fixed index structure and they cannot be easily adapted to fit new environment. In this paper a KM framework is proposed that combines ontology, case templates and case-based reasoning to solve the problems. In this framework, enterprise ontology provides the basis for integration among knowledge resources. Case templates can be reconfigured based on the enterprise's ontology by the user. The knowledge structure and the user-interfaces of the system knowledge structure and the user-interface of the system can be reconfigured so that the system can suit for an enterprise whose knowledge structure and the requirement for knowledge management system change rapidly. Besides, a workflow based knowledge acquisition method is also discussed that assures the quality of the knowledge acquired.

For large-scale software system development, many configuration items will be produced during software life cycle and every configuration item will evolve independently. Therefore, there is a need for adopting a suitable model to describe the configuration items, the relationship among them, the evolving of a single item and the constraints of the system. By means of UML class diagram, we propose a software configuration meta-model to express configuration items, relationships among the items and the evolvement of each configuration item. The model consists of three kinds of classes: configuration item, port and version. We also defined four relationships: aggregation, generalization, dependency and successor. The notion of port is used to describe the static properties and dynamic behaviors of a configuration item. The constraints of configuration items are defined using the object constraint language (OCL). The model must conform to several constraints: well-formed configuration, behavior equivalence, upward compatibility, and structural conformance. In short, the model can express complex software product structure and describe constraints in a precise way. It provides a strong basis for controlling change and supporting support management and development in the large-scale software system.

In a workflow management system, two facts are often observed: (1) the processing capacities for activities may not be fully utilized all the time, even that for critical activities; and (2) the lifecycle of a task can be partitioned into two parts: preparation phase and actual execution phase. In order to shorten the lifecycle of a workflow process instance, it is better to overlap the actual execution of a task and the preparation of its successor as long as possible. Aiming at this goal, this paper introduces the concept of task pre-dispatching into workflow management systems and analyzes when and under what circumstances a task should be pre-dispatched. Then a formalized workflow model as well as a scheduling algorithm is presented to support it. Finally, it is shown from a quantitative analysis that our approach is useful in practice.

Using e-commerce over the Internet is very cheap and convenient, which enlarges the view of enterprises and lets the enterprises have more chances to select their partners. To achieve these goals, we need the support of information systems, in which workflow management system is of significance. The inherent characteristics of a workflow system make it suitable to implement the cross organization management. Nowadays, however, systems which support cross organization management are not common. When developing a supply chain management system for a big motorcycle corporation in China, we have to construct an inter-enterprises workflow Architecture over Internet for the system by ourselves. The main part of the Architecture is a workflow supported inner supply chain and an integrated interface, through which the whole supply chain system cross several independent enterprises is constructed and the information exchange is fulfilled. This paper introduces how the system is designed and implemented in detail.

In order to improve a supply chain's rapid response capability to market opportunity and to optimize the value flow in supply chain management, this paper suggests that an important element to survival in these changed conditions is "agility", particularly by the creation of a responsive supply chain. Agility is interpreted as the quick creation of a supply chain system based on reconfiguration technology. This paper proposed a Web based agile architecture of a supply chain management system, comprised of a wizard based Web site in front-end agility and multi-agent/workflow based business process re-configuration in back-end agility.