Jongmyung Choi

Context-driven requirements analysis

Context-awareness is an important feature of ubiquitous computing systems. Compared to traditional systems, context-aware systems have different features such as heterogeneity, high complexity, and artificial intelligence, so that the need for its own development methodology increases. In this paper, we define context and context-aware service as both concrete and evaluative forms, and introduce a requirement analysis process, context-aware use case diagram, context-switch diagram, and dynamic service model based on those definitions. We expect that our work will help analysts and designers to understand, analyze, and design context-aware systems more efficiently.

MyGuide: A Mobile Context-Aware Exhibit Guide System

Recently there have been researches on smart exhibition guide systems for visitors convenience. In this paper, we introduce a context-aware, visitor-oriented guide system and some context related issues encountered during the development process. Our system provides a visitor with the most suitable guide information on the exhibit in both its content and its media format. For visitor-oriented guide service, we adopt four types of context information: visitors location, visitors background knowledge, media type supported by the terminal device, and visitors preferred language. We also show how to model context in an object-oriented approach, how to apply ECAM software architecture to our system, and how to build our prototype system using RFID, MIDP APIs, and context-awareness.

RFID Context-Aware Systems

For several decades, RFID technology has been advancing and widening its application fields by penetrating into the traditional industries with the benefits of efficiency, costs saving, and fast processing. As the result, nowadays it is widely used in logistics, inventory, security, supply-chain, manufacturing, and retails industries. For example, Wal-Mart required its top 100 suppliers to attach RFID tags to their goods [1], and logistics and manufacturing companies including Siemense have been adopting RFID rapidly [2]. Experts expect that it will widen faster its application fields thanks to low tag cost, advance in network technology, and various trials of combining ICT (information and communication technologies). With ICT, RFID systems are providing users with smarter services such as world-wide object identification, and world-wide monitoring and tracking objects. In the ubiquitous computing, context-awareness is one of the hottest issues in the academia and the industries. The basic idea of context-awareness is that the systems are able to recognize not only environmental condition and events but also internal system status, and provide users with smart services that fit on users’ intention and their current situation. We call these external and internal conditions and events as context. Therefore, context-aware systems usually have sensing sub-systems that recognize the environmental condition and events and a smart module that determines the current context and the services according to the context. For sensing sub-system, they adopt camera, temperature sensor, GPS, motion sensor, and other sensors. As you might expect, RFID’s identifation facility is also an important source of sensing the external condition and events. In fact, there have been a myriad of works that apply RFID to context-aware systems. Some read user data from tag to provide smart services according to user’s role [3], and anothers identify user location by reading tags attached to fixed objects to provide services related to the location [4,5]. Still anothers recognize user’s intention by reading object identifiers and provide services about the objects [6]. These RFID-based context-aware systems are very diverse and the number of these systems is increasing. Though RFID has been gaining interests in context-aware systems, little attention has been paid to studies on survey of existing systems or studies on context-awareness in RFID systems in detail. These studies are needed to help system stakeholders understand RFID-based context-aware systems. Therefore, we survey the existing systems and introduce our RFID context-aware system in detail. We have two purposes for this article. The first one is to survey and classify existing RFID context-aware systems. By surveying the existing applications, we identify what kinds of context are used, what kind of context-aware services they provide. We group these applications into five categories according to the data

Software Architecture for Extensible Context-Aware Systems

This paper is about a software architecture, named WCAM (watcher, controller, action, and model), which reduces the complexity of context-aware systems by decoupling of concerns. We first introduce general requirements of context-aware systems. Next, we present our architecture pattern, WCAM. Watcher perceives external environment, and controller manages the cooperation between watcher and model. Model gathers contextual information, interpret the information, and generate contexts for system. Action manages services that are related with contexts.

A Smart Service Robot Middleware on Ubiquitous Network Environments

As the importance of robot software has increased, a number of research on robot middleware within client-server architecture has been produced for the past several years. Those middleware usually provide convenient environments, where developers are able to develop robot services in conjunction with the existing libraries. Therefore, rich libraries are essential in the robot middleware. This paper introduces experience learned while developing robot software using the middleware. The middleware allows a robots functions to be described in XML, to be registered to a Web Service server, and to be reused as a Web Service. The approach has some advantages: separation a robots abstract behaviors from hardware dependent implementation, reuse of the existing robot software implementation, and finally, the possibility of cooperation among various robots.

Use-Case Driven Requirements Analysis for Context-Aware Systems

Context-awareness and context-aware systems have been getting popular but there have been only a few of researches on requirements analysis method for context-aware systems. In this paper, we propose a requirement elicitation method for context-aware systems. We contend that analysts should consider system platform, target users, and service intelligence as context related issues, and we also argue that they should gather and document context related issues during use case gathering process because context related information is very important in context-aware systems. Our work contributes to context-aware system field because we consider context information as first citizen of software engineering, so that users, analysts, and designers have some agreement on context-aware services.

Software Engineering Issues in Developing a Context-aware Exhibition Guide System

Context-awareness is a key feature of ubiquitous computing, but it is difficult to develop context-aware systems because they are complex and because developers are not familiar with the development methodology for the systems. In this paper, we introduce a method to apply software engineering techniques when developing a context-aware system. Based on our experience in developing a context-aware exhibition guide system, we show how to elicit requirements, how to model context, how to determine system architecture, how to design the system, and how to implement the system. Our study will help developers to efficiently develop context-aware systems according to software engineering principles.

Context: From Birth to Design

Developers should consider contexts and their features carefully because they influence artifacts generated during the context-aware system development process. This paper is about context, its features, and their influence on the development. We introduce the definition context and its related concepts in measurable terms, and the features of context from the perspective of software development. Furthermore, we also introduce how context features influence requirement elicitation and context modeling, and how context modeling influence software architecture and system design. Our study will help context-aware system developers to reduce trial and errors by introducing issues to be considered during the development process.

Texture Extraction from Video and Image Warping for AR Coloring Book

Augmented reality is a technology which superimposes virtual objects on real world to provide users with useful information and user interface. AR coloring book is interesting application. In this paper, we propose a texture extraction method from video and image warping method for augmented reality coloring book with vuforia SDK. To realize this idea, we made algorithm to extract specific rectangular area on a paper from video in real-time, and then transforms the image of area into rectangular shape for texture mapping. We expect that our approach will be useful when developers implement new function to AR coloring book with vuforia SDK.

Framework for Interaction Among Human–Robot-Environment in DigiLog Space

With the development of computing technology, robots are now popular in our daily life. Human–robot interaction is not restricted to a direct communication between them. The communication could include various different human to human interactions. In this paper, we present a framework for enhancing the interaction among human–robot-environments. The proposed framework is composed of a robot part, a user part, and the DigiLog space. To evaluate the proposed framework, we applied the framework into a real-time remote robot-control platform in the smart DigiLog space. We are implementing real time controlling and monitoring of a robot by using one smart phone as the robot brain and the other smart phone as the remote controller.