Inyoung Ko

UML activity diagram is a notation suitable for modeling a concurrent system in which multiple objects interact with each other. This paper proposes a method to generate test cases from UML activity diagrams that minimizes the number of test cases generated while deriving all practically useful test cases. Our method first builds an I/O explicit activity diagram from an ordinary UML activity diagram and then transforms it to a directed graph, from which test cases for the initial activity diagra

Given a vector field defined on a robot’s configuration space, in which the vector field represents the system drift, e.g. a wind velocity field, water current flow, or gradient field for some potential function, we present a randomized path planning algorithm for reaching a desired goal configuration. Taking the premise that moving against the vector field requires greater control effort, and that minimizing the control effort is both physically meaningful and desirable, we propose an integral

As various types of Internets of Things (IoT) are deployed in a wide range of areas, the need arises to utilize various IoT resources dynamically to accomplish user tasks. We call this environment an urban-scale IoT environment, where various IoT resources that are necessary to accomplish user tasks are directly connected to each other via users' mobile devices, such as their smart phones. IoT resources are utilized as resources with which to run a composite service that supports user tasks. In

An emerging issue in urban computing environments is the seamless selection, composition, and delivery of user-centric services that run over what is known as the Internet of Things (IoT). This challenge is about enabling services actuated by IoT devices to be delivered spontaneously from the perspective of users. To accomplish this goal, we propose the Service-Oriented Internet of Things (SoIoT), a user-centric IoT-based service framework, which integrates services that utilize IoT resources in

Abstract: RDF-based tools promise to provide a base for reasoning about metadata and about situated data—data describing entities situated in time and space—that is superior to alternatives such as relational databases or object-oriented databases. However, essential representational machinery is missing from the current generation of Semantic Web tools and languages. When that machinery is added, the resulting capabilities offer a combination of novelty and flexibility that may usher in a wave

In task-oriented service computing, a user's computing goal is modeled and represented as a task, which is composed of activities that are performed by accessing service instances in a local environment. The abstract service requirements specified in an activity of a task are resolved and bound to service instances dynamically in runtime. When there are many candidate services that provide similar capabilities for a task, it is essential to consider quality of service (QoS) such as response time

In regression testing, running all a system's test cases can require a great deal of time and resources. Test case prioritization (TCP) attempts to schedule test cases to achieve goals such as higher coverage or faster fault detection. While code coverage-based approaches are typical in TCP, recent work has explored the use of additional information to improve effectiveness. In this work, we explore the use of Information Retrieval (IR) techniques to improve the effectiveness of TCP, particularl

Behavioral, situational and environmental changes in complex software, such as robot software, cannot be completely captured in software design. To handle this dynamism, self-managed software enables its services dynamically adapted to various situations by reconfiguring its software architecture during run-time. We have developed a practical framework, called SHAGE (Self-Healing, Adaptive, and Growing SoftwarE), to support self-managed software for intelligent service robots. The SHAGE framewor

By making it easy to explore combinations of multiple Web services, Eurasia helps users tackle large-scale information-management tasks and adapt and reuse the steps involved.

The Vector Field Rapidly-exploring Random Tree (VF-RRT) algorithm is an extension of the RRT algorithm for planning in the presence of vector fields; its main distinguishing feature is that random nodes are generated in such a way that the trees tend to extend along the directions of the given vector field. By constructing vector fields to be aligned in the direction that minimizes the upstream cost, which is a new criterion for measuring the extent to which a path moves against the vector field

Dynamic Web content provides us with time-sensitive and continuously changing data. To glean up-to-date information, users need to regularly browse, collect and analyze this Web content. Without proper tool support this information management task is tedious, time-consuming and error prone, especially when the quantity of the dynamic Web content is large, when many information management services are needed to analyze it, and when underlying services/network are not completely reliable. This pap

. Representing and processing semantic information regarding individual documents is desirable but not sufficient. To improve the efficiency and reusability of users' work with Web-based information management systems, it is essential to handle document collections. We describe techniques for representing semantics both of collections and of information management services that operate upon them. These techniques help users set up complex analyses and structurings of information collect