This paper presents a middleware system for multi-agents on a distributed system as a general test-bed for bio-inspired approaches. The middleware is unique to other approaches, including distributed object systems, because it can maintain and migrate a dynamic federation of multiple agents on different computers. It enables each agent to explicitly define its own deployment policy as a relocation between the agent and another agent. This paper describes a prototype implementation of the middleware built on a Java-based mobile agent system and its practical applications that illustrates the utility and effectiveness of the approach in real distributed systems.

We present a world model for location-aware and user-aware services in ubiquitous computing environments. It can be dynamically organized like a tree based on geographical containment, such as in a user-room-floor-building hierarchy and each node in the tree can be constructed as an executable software component. The model is unique to existing approaches because it enables location-aware services to be managed without databases, can be managed by multiple computers, and provides a unified view of the locations of not only physical entities and spaces, including users and objects, but also computing devices and services. A prototype implementation of this approach was constructed on a Java-based mobile agent system. This paper presents the rationale, design, implementation, and applications of the prototype system.

We present a model checking approach to the rationale, implementation, and applications of a query language for location-based services. Such query mechanisms are necessary so that users, objects, and/or services can effectively benefit from the location-awareness of their surrounding environment. The underlying data model is founded on a symbolic model of space organized in a tree structure. Once extended to a semantic model for modal logic, we regard location query processing as a model checking problem, and thus define location queries as hybrid logic-based formulas. Our approach is unique to existing research because it explores the connection between location models and query processing in ubiquitous computing systems, relies on a sound theoretical basis, and provides modal logic-based query mechanisms for expressive searches over a decentralized data structure. A prototype implementation is also presented and will be discussed.

This paper presents a framework for building mobile agent-based components. The framework introduces the notion of agent hierarchy and inter-agent migration and thus allows a group of mobile agents to be dynamically assembled into a single mobile agent. It provides a powerful method of constructing complex, large-scale mobile agent-based applications. To demonstrate how to exploit our framework, we construct an extensible and portable mobile agent system for executing and migrating hierarchical mobile agents. The system itself is also implemented as a collection of mobile agents and can thus dynamically change and adapt its functions through migrating agents that offer the functions. Mobile agent-based applications running on the system can naturally inherit the extensibility and adaptability of the system.

A component framework for building and operating visual interfaces for context-aware services in ubiquitous computing environments is presented. By using a compound-document technology, it provides physical entities, places, stationary or mobile computing devices, and services with visual components as multimedia representations to enable them to be annotated and controlled them. It can automatically assemble visual components into a visual interface for monitoring and managing context-aware services according to the spatial-containment relationships between their targets in the physical world by using underlying location-sensing systems. End-users can manually deploy and customize context-aware services through user-friendly GUI-based manipulations for editing documents. This paper presents the design for this framework and describes its implementation and practical applications in user/location-aware assistant systems in two museums.

In this paper we present a component approach for configurable network processing for active documents. The approach has two key ideas. The first is to enable documents to process themselves on networks. That is, documents can define their own itineraries, like the notion of active packets in active network technology. The second is to enable documents to transmit other documents to their destinations as first-class objects, such as the notion of active nodes in active netwwork technology. The approach also enables buidling and managing active documents as compound documents. The dynamic deployment of network processing for exchanging documents can be defined and achieved by means of GUI-based manipulation of compound documents. Therefore, the approach allows a user to easily and rapidly develop and customize network processing in the same way as if that user had edited the documents. A prototype implementation of the approach and its applications were constructed on a Java-based mobile agent system to evaluate the effectiveness of the approach.

A formal approach for specifying and reasoning about earth-friendly logistics management systems is presented. To reduce fossil fuel consumption and carbon dioxide emissions resulting from transport, we must enhance the transport efficiency of trucks, which play an essential role as carriers in modern logistics services. This paper addresses the milk-run approach. It is one of the most effective and popular solutions to this problem, but it makes it be complicated to implement in a logistics management system. We propose a language for specifying the routes of trucks and an order relation between the requirements of routes and the possible routes of trucks. The former is formulated as process calculus and the latter selects suitable trucks according to their routes.

This paper presents an agent-based system for building and operating context-aware services in public spaces, including museums. The system provides users with agents and detects the locations of users and deploys location-aware user-assistant agents at computers near the their current locations by using active RFID-tags. When a visitor moves between exhibits in a museum, this dynamically deploys his/her agent at the computers close to the exhibits by using mobile agent technology. It annotates the exhibits in his/her personalized form and navigate him/her user to the next exhibits along his/her routes. It also introduces user movement as a natural approach to interacting between users and agents. To demonstrate the utility and effectiveness of the system, we constructed location/user-aware visitor-guide services and experimented them for two weeks in a public museum.

In a ubiquitous computing environment, people are surrounded by hundreds of mobile or embedded computers each of which may be used to support one or more user applications due to limitations in their individual computational capabilities. We need an approach to coordinating heterogeneous computers that acts as a virtual computer around a mobile and ubiquitous computing environment and supports various applications beyond the capabilities of single computers. This paper presents a framework for building and aggregating distributed applications from one or more mobile components that can be dynamically deployed at mobile or stationary computers during the execution of the application. Since the approach involves mobile-transparent communications between components and component relocation semantics, it enables a federation of components to adapt its structure and deployment on multiple computers whose computational resources, such as input and output devices, can satisfy the requirement of the components in a self-organized manner. This paper also describes a prototype implementation of the approach and its application.

A framework for deploying application-specific overlay networking is presented. It enables network protocols for transmitting data and agents to be naturally facilitated as mobile agents. It can also implement the deployment of mobile agent-based protocols within mobile agents. It can customize the deployment of network protocols as well as data transmission by migrating and replacing corresponding mobile agent-based protocols. It provides a self-deployment mechanism for the overlay network. This paper describes the system and its prototype implementation, which uses Java as both the implementation language and the protocol development language.

This paper proposes a framework for building a reusable mobile agent from two kinds of components: an itinerary component and an application-specific logic component. Both components are implemented as mobile agents. The former is a carrier of the latter over particular networks and the latter defines management tasks performed at each host independently of the network. This framework also provides a mechanism for matchmaking the two mobile agent-based components. Since the mechanism is formulated based on a process algebra approach, it can strictly select a suitable itinerary component to perform management tasks at the hosts that the tasks want to visit over the networks. A prototype implementation of this framework and its application were built on a Java-based mobile agent system. We summarize the lessons learned while formalizing and implementing the approach and we compare it to related work.