Yohei Murakami

Multi-agent simulation for crisis management

Traditional crowd simulators are based on a simple numerical analysis of inputs such as the positions of people and structures; they do not consider leadership. Since leaders (in terms of evacuations) are present in many real-world situations, the validity of evacuation simulations can be increased through their introduction. We assess the results of a real-world evacuation experiment to develop more realistic scenarios for simulation. The simulations produced by the improved scenarios are found to closely mimic the experimental results. This work shows that scenario-based agent systems such as FlatWalk and FreeWalk offer excellent promise in simulating evacuations more realistically.

Scenario description for multi-agent simulation

Making it easier to design interactions between agents and humans is essential for realizing multi-agent simulations of social phenomena such as group dynamics. To realize large-scale social simulations, we have developed the scenario description languages Q and IPC (Interaction Pattern Card); they enable experts in the application domain (often not computing professionals) to easily create complex scenarios. We have also established a four-step process for creating scenarios: 1) defining a vocabulary, 2) describing scenarios, 3) extracting interaction patterns, and 4) integrating real and virtual experiments. In order to validate the scenario description languages and the four-step process, we ran a series of evacuation simulations based on the proposed languages and process. We successfully double-check the result of the previous controlled experiment done in a real environment.

A Hybrid Integrated Architecture for Language Service Composition

This paper reports on our experiences with combining Heart of Gold and Language Grid technology to provide more language resources available on Web. Heart of Gold is known as middleware architecture for integrating deep and shallow natural language processing components. The language grid is an infrastructure built on top of the Internet to provide distributed language services. Having Heart of Gold available as Web services in the language grid environment would contribute to interoperability among language services.

Language Grid Association: Action Research on Supporting the Multicultural Society

The Language Grid is a middleware with which people can connect and use language resources such as machine translations, morphological analyzers and others created in the fields of intercultural collaboration. The Language Grid cannot exist without the collaboration of Language Grid Users who provide language and computation resources, language services, and collaboration tools. This paper overviews Language Grid Association, a user group of the Language Grid and a body promoting action research to support the multicultural society.

Service Supervision: Coordinating Web Services in Open Environment

A composite Web service designed based on abstract Web services, which define only interfaces, allows an application developer to select services required for his application only by setting endpoints for the atomic Web services. In open environment, however, the composite Web service configured in this manner may fail due to unique behaviors of the selected services. It is difficult for the designer of the composite Web service to prevent the failure because he does not know which services are selected and how they behave. On the other hand, the application developer is not authorized to modify the composite Web service due to the need to protect intellectual rights. Our solution is Service Supervision, which monitors and controls execution of composite Web services. Service Supervision makes the followings possible. 1) An application developer can control the behavior of a composite Web service by changing the execution state, even if the he is not authorized to modify the composite Web services. 2) A control pattern for coordinating Web services can be applied to various composite Web services in order to reduce the load imposed by designing control processes. In order to realize Service Supervision, we introduce meta-level control of a composite Web service. Moreover we then use the choreography to define the interaction protocols for the controls. The proposed framework is based on existing standard languages, WS-BPEL and WS-CDL. Therefore we can exploit existing tools and expertise of SOA engineers.

Infrastructure for Language Service Composition

Although English has become the standard language in various areas, most people do not use it in local activities. To increase the mutual understanding of different cultures with different languages, it is essential to build a language infrastructure on top of the Internet that improves the accessibility and usability of existing online language services so that users can create new cross-language services for their communities. To realize this infrastructure, this paper proposes the language grid. The language grid consists of the ”horizontal language grid,” which connects the standard languages of nations, and ”vertical language grid,” which combines the language services generated by communities. This approach can facilitate intercultural collaboration through the Internet, such as international online collaborative learning.

Service Grid Federation Architecture for Heterogeneous Domains

Service grid is an infrastructure for service-oriented collective intelligence. It provides a set of enabling functionalities to support coordination of services, such as service registries, service composition, access control, and monitoring. To form the service-oriented collective intelligence, various types of services need to be connected on the service grid, and managed by the service grid operator. However, it is difficult for single service grid operator to gather and organize services in various domains. Therefore, building service grids in different domains and connecting these service grids are essential for expanding service-oriented collective intelligence across domains. To this end, we have designed a service domain model to specialize general-purpose service grid to a specific domain and realize interoperability among service grids. Moreover, we have also developed service grid federation architecture to share service registries, compose services across service grids, and control and monitor accesses to the composite services. Finally, we have applied the proposed architecture to the language service domain to construct the Language Grid.

Situated Web Service: Context-Aware Approach to High-Speed Web Service Communication

A framework is proposed to improve Web service performance based on context-aware communication. Two key ideas are introduced to represent a client context: (1) available protocols that the client can handle, and (2) operation usage that shows how the client uses Web service operations. We call our context aware approach a situated Web service (SiWS). We implemented and evaluated the SiWS and found that the overall performance was improved if more than three Web services were executed between context changes

Service-Oriented Architecture for Interoperability of Multilanguage Services

Since the Internet increases the opportunity to interact with foreign people in daily life, multilingual communication tools are necessary. However, the applicability of multilingual communication tools is generally limited because the quality of translation is not high enough to translate an arbitrary text correctly. To develop a multilingual environment that can handle various situations in various communities, existing language resources (dictionaries, parallel texts, part-of-speech (POS) taggers, machine translators, etc.) should be easily shared and combined beyond their complicated intellectual property problems and mismatch of their interfaces. Therefore, we introduce a service-oriented architecture to realize the Language Grid. It allows users to realize interoperability of language services and easily compose those language services to support multilingual communication. This chapter explains the system architecture of the Language Grid and its service domain model to define service interfaces and service profiles.

Service Grid Architecture

The Language Grid is an infrastructure for enabling users to share language services developed by language specialists and end user communities. Users can also create new services to support their intercultural/multilingual activities by composing language services from a range of providers. Since the Language Grid takes the service-oriented collective intelligence approach, the platform requires the services management to satisfy stakeholders’ needs: access control for service providers, dynamic service composition for service users, and service grid composition and system configurability for service grid operators. To realize the Language Grid, this chapter describes the design concept and the system architecture of the platform based on the service grid.