Wenpin Jiao

Towards a unified formal model for supporting mechanisms of dynamic component update

The continuous requirements of evolving a delivered software system and the rising cost of shutting down a running software system are forcing researchers and practitioners to find ways of updating software as it runs. Dynamic update is a kind of software evolution that updates a running program without interruption. This paper covers the fundamental issues of the mechanisms of dynamic update theoretically. Based on a similarity analysis of many typical approaches to dynamic update during the past decades, we propose a unified formal model (namely, Dynamic Update Connector) to specify mechanisms of updating an architectural component, and reason about its properties. The model borrows the concept of connectors from software architecture community and is specified using process algebra CSP. We also demonstrate the applications of our DUC model.

Formal framework for adaptive multi-agent systems

Evolution of software challenges multi-agent systems to be adaptive and the adaptation capabilities should be provided at both the agent level and the system level. In this paper, we study the adaptation of multi-agent systems from the system level and describe a formal framework for multi-agent systems with adaptation capabilities. In the framework, agents are indirectly interconnected via roles and interaction protocols are defined as entities independent of agents and roles. Thus, agents, roles, and interaction protocols involved in multi-agent systems need not always adjust their behaviors or specifications to adapt to the changes of system structures and interaction protocols.

Dynamic Interaction Protocol Load in Multi-Agent System Collaboration

Multi-agent system(MAS) has more advantages because the agents can collaborate to complete complex tasks. However, the multi-agent interactions are more complex and even uncontrolled and it is difficult to resolve the multi-agent collaborations. This paper focuses on the interaction protocol in MAS. Firstly the interaction ontology library including role ontology, action ontology and message ontology is introduced into the semantic interactions. Then the representation of interaction protocol is presented, which describes an interaction protocol as process description and decision-making rules. Then we propose a three-layer agent architecture that contains knowledge layer, collaboration control layer and communication layer. We embed a protocol interpreter and loader into the collaboration control layer to deal with the interactions between agents. Finally dynamic interaction protocol load in MAS are discussed, which load the interaction protocol from protocol library conveniently and the code will be generated automatically. To the end we give an experiment to verify our resolution.

Automated adaptations to dynamic software architectures by using autonomous agents

Software architectures should always reflect the architectural changes occurring in software systems. In this paper, dynamic software architectures are studied from a new perspective. Software architectures are considered as goals or objectives that software systems are pursuing instead of constraints over systems. The architectural goals are decomposed into two categories of sub-goals, i.e., structural goals and interaction behavioral goals. For defining the architectural goals of software systems, the notation of architectural reference model is introduced. The architectural reference model is composed of components and connectors involved in software architectures and constraints over software architectures. For reasoning about the result of changes rigorously and automatically, software architectures and changes to software architectures are described in a uniform formalism and the results of changes can directly be derived from the compositions of software architectures and changes. For implementing the adaptations of software systems, an autonomous agent-based approach is adopted, in which autonomous agents are used to plan the achievement of architectural goals and cascade reactions caused by changes via using architectural style-specific knowledge and behavior rules defined for agents.

Automating integration of heterogeneous COTS components

Mismatches make COTS components difficult to be incorporated. In this paper, an approach is presented to eliminate mismatches among COTS components, which can truly consider COTS components as black boxes. In the approach, only the assembly description of components is required, based on which adaptors for resolving mismatches can be generated automatically. This paper also described an agent-based GUI implementation of the approach.

Customizable framework for managing trusted components deployed on middleware

Due to the widespread trust threat under the open and dynamic Internet environment, the computer community has endeavored to engage in the studies of technologies for protecting and evaluating trustworthiness. This paper firstly defines trust from three aspects: trust relationship, trust property and trust entity, and build a uniform view for multiple trust properties. Secondly, according to abstract the common characteristics over varied trust properties, a model of trust management is elaborated, in which the trust entities, measurement model and trust policy are described. Thirdly, the trust management is implemented as a kind of public service on a J2EE-compliant middleware platform, i.e., the PKUAS.

Automated assembly of Internet-scale software systems involving autonomous agents

On the Internet, there is a great amount of distributed software entities deployed independently and behaving autonomously. This paper describes an automated approach to constructing Internet-scale software systems based on autonomous software agents. In the approach, the systems are modeled by interconnected divisions and cooperative roles. The approach adopts a dynamic trial-and-evaluation strategy to select high quality autonomous agents to undertake the responsibilities of roles, and implements a special mobile agent, called delegate, carrying the interaction information specified for responsibilities of roles to facilitate the interoperations among autonomous agents. The experiments show that the approach is highly scalable and improves the overall qualities of systems remarkably.

AN APPROACH TO CONSTRUCTING HIGH-AVAILABLE DECENTRALIZED SYSTEMS VIA SELF-ADAPTIVE COMPONENTS

In decentralized computing environments, systems are built mainly from components that are developed and maintained independently by different third-party providers. The executions and evolutions of components located on distributed sites are beyond the control of the system developers, and the availabilities of those components are, to some extent, unpredictable because of their own tendencies and the unstable network. As a result, it is still a great challenge to construct high-available decentralized systems. In this paper, a self-adaptive component model is proposed to model those components distributed on the Internet and a running framework is described for constructing systems composed of self-adaptive components. Self-adaptive components can adjust their knowledge about the availabilities of the required services via learning from the feedback of historical invocations. Based on the knowledge, components can find the most appropriate service providers effectively and automatically. Experiments show that systems can always gain high availabilities under dynamic decentralized environments by using the approach.

An Online Education Approach Using Web Operation Record and Replay Techniques

Online education plays a more and more important role in the era of Internet and cloud computing, but two problems remain unsolved including MOOCs. First, most of existing online education platforms only provide teaching materials in format of ppt, pdf, video, and they seldom support education based on graphical Web applications. Second, some online education platforms may provide self-governed chatting tools or whiteboards, but they are not combined with teaching materials closely. As a result, they cannot satisfy the need for the real-time interactions based on complex teaching materials. To solve the problems above, we put forward an online education approach using Web operation record and replay techniques, and implement online synchronized education and real-time interactions between teachers and students. Moreover, we develop a supporting tool OSEP for the approach. In the case study, we describe three education scenarios, which verify that the approach supports not only personal learning by tutorials and wizards, but also online in-class real-time collaborative learning.

Dynamic architectural connectors in cooperative software systems

In cooperative software systems, the interconnection relationships between components are often dynamic and unpredictable and therefore connectors have to be created dynamically. In this paper, we bring forward the concept of dynamic architectural connector to provide dynamic interconnectivities for components. This paper proposes an automated approach based on software agents to generate dynamic connectors. In the approach, dynamic interaction relationships are established via negotiations and dynamic connectors are generated automatically as high-order entities via taking the behavior specifications and the ontologies of components as arguments. Based on the formal study on the interconnectivities of components, the approach is proved competent for generating dynamic connectors that can satisfy the requirements for providing correct dynamic interconnectivities for components.