• Journal of Information Technology Services
• /
• v.12 no.4
• /
• pp.399-422
• /
• 2013

The aim of this study is to find the model that best explains members' continued use intention in virtual communities by comparing technical and social perspectives applied in IS context. With the eight major variables identified from prior studies, four alternative models were formulated:1) A base model from Information Systems (IS) continuance perspective, 2) IS continuance model with technology-acceptance perspective, 3) IS continuance model with social-capital perspective, and 4) IS continuance model with socio-technical combined perspective. The adequacies of these four models with different perspective highlighted were tested using survey data collected from virtual community users in Korea. The findings indicated that the IS continuance model and social-capital perspective is the most efficient model that best explains the members' continued use intention in virtual communities.

• Journal of the Korea Society of Computer and Information
• /
• v.22 no.2
• /
• pp.9-19
• /
• 2017

Useful continuous sensing applications are increasingly emerging as a new class of mobile applications. Meanwhile, open, multi-use sensor devices are newly adopted beyond smartphones, and provide huge opportunities to expand potential application categories. In this upcoming environment, uncoordinated use of sensor devices would cause severe imbalance in power consumption of devices, and thus result in early shutdown of some sensing applications depending on power-hungry devices. In this paper, we propose EnergyCordy, a novel inter-device energy use coordination system; with a system-wide holistic view, it coordinates the energy use of concurrent sensing applications over multiple sensor devices. As its key approach, we propose a relaxed sensor association; it decouples the energy use of an application from specific sensor devices leveraging multiple context inference alternatives, allowing flexible energy coordination at runtime. We demonstrated the effectiveness of EnergyCordy by developing multiple example applications over custom-designed wearable senor devices. We show that EnergyCordy effectively coordinates the power usage of concurrent sensing applications over multiple devices and prevent undesired early shutdown of applications.

• Journal of Information Technology Applications and Management
• /
• v.11 no.2
• /
• pp.125-148
• /
• 2004

It is quite sure that e-commerce through internet has significant impacts on consumer behavior and marketing activities as well. In this context, the concept of 'Internet Community' has been emerged and highlighted in consumer marketing. Internet community means social relationships and linkages which can be established through continuous and iterative internet-mediated communications among people with homogeneous interests and concerns. It has been a current trend to exchange product information among consumers by forming internet communities, which would affect sales performance directly or indirectly. It, therefore, is necessary to study the community's behavior and its impact on its marketing performance. This article focuses on the following points : ① the structural concept and factors of forming traditional consumer community and internet community : ② the role of trust and commitment as mediating variables between the internet community formation and marketing performance : ③ the performance and implications of the internet community on marketing.

• IE interfaces
• /
• v.18 no.4
• /
• pp.465-476
• /
• 2005

Evolutionary operation is a useful tool for improving full-scale manufacturing process by systematically changing the levels of the process variables without jeopardizing the product. This paper presents a system design for the evolutionary operation software called 'evolutionary optimizer'. Evolutionary optimizer consists of four modules: factorial design, many variables, mixture, and mean/dispersion. Context diagram, data flow diagram and entity-relationship modelling are used to systematically design the evolutionary optimizer system.

• The Journal of Korea Robotics Society
• /
• v.9 no.4
• /
• pp.197-205
• /
• 2014

As computer vision algorithms are developed on a continuous basis, the visual information from vision sensors has been widely used in the context of simultaneous localization and mapping (SLAM), called visual SLAM, which utilizes relative motion information between images. This research addresses a visual SLAM framework for online localization and mapping in an unstructured seabed environment that can be applied to a low-cost unmanned underwater vehicle equipped with a single monocular camera as a major measurement sensor. Typically, an image motion model with a predefined dimensionality can be corrupted by errors due to the violation of the model assumptions, which may lead to performance degradation of the visual SLAM estimation. To deal with the erroneous image motion model, this study employs a local bundle optimization (LBO) scheme when a closed loop is detected. The results of comparison between visual SLAM estimation with LBO and the other case are presented to validate the effectiveness of the proposed methodology.

• Journal of Computing Science and Engineering
• /
• v.7 no.4
• /
• pp.220-230
• /
• 2013

In recent years, progress in hardware technology has resulted in the possibility of monitoring many events in real time. The volume of incoming data may be so large, that monitoring all individual data might be intractable. Revisiting any particular record can also be impossible in this environment. Therefore, many database schemes, such as aggregation, join, frequent pattern mining, and indexing, become more challenging in this context. This paper surveys the previous efforts to resolve these issues in processing data streams. The emphasis is on specifying and processing sliding window queries, which are supported in many stream processing engines. We also review the related work on stream query processing, including synopsis structures, plan sharing, operator scheduling, load shedding, and disorder control.

• International Journal of Contents
• /
• v.10 no.3
• /
• pp.55-63
• /
• 2014

Existing science education that excludes narrative thinking impedes the understanding of the context of workbook content. The object of this research is to develop a storytelling-learning program based on narrative thinking to elevate learners' interest in science and expand their inventive problem-solving abilities. Following an analysis of the current Korean curriculum, eight types of storytelling materials that utilize local content were developed for grades 7-9. The learning program used quest storytelling and was designed such that learning activities such as investigation, discussion, and experimentation were included in the process of solving each quest. Learners experienced an interest in storytelling learning resulting from participation in this storytelling-learning program. Moreover, learners demonstrated inventive problem-solving abilities in the process of completing the stories. During the process of assembling the storytelling materials, the students interacted with enthusiasm and generated ideas. The teachers indicated a positive feedback to the storytelling program as a new attempt to stimulate learners' interests. In the future, with continuous development and application, storytelling-science-learning programs that base science learning on narrative thinking are expected to be successful.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.2 no.3
• /
• pp.73-81
• /
• 1998

In this paper, the necessity of developing effective nondestructive testing and monitoring techniques for the evaluation of structural integrity and performance is described. The evaluation of structural integrity and performance is especially important when the structures and subject to abrupt external forces such as earthquake. A prompt and extensive inspection is required over a large area of earthquake-damaged zone. This evaluation process is regarded as a part of performance-based design. In the paper, nondestructive testing and monitoring techniques particularly for concrete structures are presented as methods for the evaluation of structural integrity and performance. The concept of performance-based design is first defined in the paper followed by the role of evaluation of structures in the context of overall performance=based design concept. Among possible techniques for the evaluation, nondestructive testing methods for concrete structures using radar and a concept of using fiber sensor for continuous monitoring of structures are presented.

• The Journal of Information Systems
• /
• v.6 no.1
• /
• pp.5-26
• /
• 1997

The demands for continuous process optimization require a radical rethinking of how information systems are designed and constructed. Information systems must be capable of sustained, graceful change in response to evolving business requirements. This proposition is supported by the fact that information systems have helped increase productivity only when they were built to support new and better ways of conducting the business. In such context, business process engineering (BPF) is recognized the first but most critical stage in developing information systems as well as in launching business improvement and innovation projects. However, more often, there exist great gaps and inconsistencies between the results of BPE and the business itself, which turn into huge maintenance overhead during an information system lifecycle. In order to solve such an ever lasting problem, this paper orthogonal models, procedure, guide, and work flow are constructed in our engineering discussions focus on decentralized organizations, the method is general enough to be applied easily to other types of organizations without difficulties.

• 한국전산유체공학회:학술대회논문집
• /
• 2008.03a
• /
• pp.71-78
• /
• 2008

For analyses of multi-phase flows in a water-cooled nuclear power plant, a three-dimensional SIMPLE-algorithm based hydrodynamic solver CUPID-S has been developed. As governing equations, it adopts a two-fluid three-field model for the two-phase flows. The three fields represent a continuous liquid, a dispersed droplets, and a vapour field. The governing equations are discretized by a finite volume method on an unstructured grid to handle the geometrical complexity of the nuclear reactors. The phasic momentum equations are coupled and solved with a sparse block Gauss-Seidel matrix solver to increase a numerical stability. The pressure correction equation derived by summing the phasic volume fraction equations is applied on the unstructured mesh in the context of a cell-centered co-located scheme. This paper presents the numerical method and the preliminary results of the calculations.