Yoosoo Oh

A context management architecture for large-scale smart environments

Context-aware architecture collects various context data from heterogeneous sensors and provides an intelligent service by exploiting the collected data. In this article we explain the generalized context-aware software architecture for heterogeneous smart environments. The proposed architecture integrates large-scale contexts from multiple heterogeneous sensors, and makes a semantic decision by fusing and reasoning about the collected contexts. Moreover, we discuss a designed architecture that manages communities between large numbers of heterogeneous information entities and enhances intelligence abilities.

Designing, Developing, and Evaluating Context-Aware Systems

Context and context-awareness have been central issues in ubiquitous computing research for the last decade. Advances with regard to context acquisition and activity recognition allow interesting small scale applications. However in larger systems including many sensors and actuators and spanning multiple administrative domains are still remain as unsolved central issues. Particularly, in the areas of reasoning and context-fusion there are many open questions. In this paper we motivate large scale context-aware systems that have support for the full life cycle using a prototype that was implemented and tested. We then describe in detail the underlying architecture which supports dynamic context-aware systems and includes mechanisms for context fusion and reasoning. Also, we propose a new approach for evaluating context-aware systems. The approach is an adapted expert evaluation; well known in the user interface domain, but using a carefully selected set of heuristics specifically targeted at context-aware systems.

u-BabSang: a context-aware food recommendation system

In this paper, we propose a context-aware food recommendation system for well-being care applications. The proposed system, called u-BabSang, provides individualized food recommendation lists at the dining table, and is based dietary advice in the typical Korean medical text. Our proposed system receives a user’s profile, physiological signals, and environmental information around the dining table in real time. To operate our system, we present a method for user specified analysis, and also describe time-division layered context integration which integrates the multiple contexts obtained from the sensors. Thus, our system recommends appropriate foods for each individual’s health at the table in real time.

Foundation of a new digital ecosystem for u-content: needs, definition, and design

In this paper, we analyze and classify digital ecosystems to demonstrate the need for a new digital ecosystem, oriented towards contents for ubiquitous virtual reality (U-VR), and to identify appropriate designs. First, we survey the digital ecosystems, explore their differences, identify unmet challenges, and consider their appropriateness for emerging services tightly linking real and virtual (i.e. digital) spaces. Second, we define a new type of content ecosystem (u-Content ecosystem) and describe its necessary and desirable features. Finally, the results of our analysis show that our proposed ecosystem surpasses the existing ecosystems for U-VR applications and contents.

Conceptualizing u-Content Ecosystem in Ubiquitous VR Environments

In this paper, we propose a concept of u-Content ecosystem in ubiquitous VR environments. We present a definition and features of u-Content ecosystem, and describe its application scenario to interacting with users in ubiquitous VR environments. We also explain the u-Content life-cycle that includes resources, contents production, growth, evolution, reproduction, and destruction.

Stone-Type Physiological Sensing Device for Daily Monitoring in an Ambient Intelligence Environment

Recently there has been increasing research into mobile physiological sensing devices to explore the benefits in the areas of monitoring health and well-being. However, previous works have mainly focused on functionality, and less so on affective shape, comfort use, and stable sensing. In this work, we propose a stone-type physiological sensing device for general users, rather than professional experts. We found that our device was comfortable, stable and had aesthetic appeal for users during monitoring. To develop an affective shape, and to increase comfort, we applied a user-centered design process. We also used context-based physiological signal analysis to obtain stable analysis results according to individual users. As an application, we developed a rainbow ambient display to give visual feedback to users. We expect that this product can be applied in various healthcare applications.

An Architecture for Flexible Entity Configuration in a Simulation Environment

Recently, peoples interest is on the rise for virtual simulation as witnessed from a large number of applications using virtual space. Especially, simulations for ubiquitous environment focus on generating realistic data, context, contextual interpretation and have characteristics such as systematic testing, detection of rule confliction, and provision of context-aware modules. The previous works only consider systematic functionalities, but do not consider how to easily configure entities in a simulation environment for a user. To make up for these limitations, we propose a system architecture for flexible entity configuration in a simulation environment for smart space. The proposed system architecture removes dependency which is related to a parameter among functions of each entity, and independently interprets and generates context information. An application developer can implement graphical user interface(GUI) of new entities without considering the structural dependency about overall GUI of the system. Therefore, the proposed system architecture is expected to provide flexible simulation environment for an application developer to test an entity by cost effectiveness.

Widget-Based simulator for testing smart space

In this paper, we propose a widget-based simulator for testing smart space by using virtual space. It is especially useful within this simulation field, because virtual space alleviates limited constraints such as time, space, technique, and cost. Researchers within this ubiquitous computing field use virtual space to simulate entities such as sensors, actuators, and services. Previous works focus more on systematic functions rather than simulation space configurations, and they consider only single service unit simulations. However, our proposed simulator focuses on the easy configuration of simulation space, which users want, and the simulation of entities such as detailed units (e.g., actuators, sensors, and context-awareness). Our simulator supports the set up of a variety of services by using dynamic links. For the design of our simulator, we consider widget-based virtual entities and plug-in techniques. We configure a virtual smart home in order to test our proposed simulation. We also evaluate the robustness of our proposed simulation. Finally, the proposed simulator is expected to provide a simulation environment in which simulation space and testing are made more effective for users.