• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.5
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• pp.739-746
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• 1994

This paper present an efficient methodology to solve the unit commitment problem for large scaled power system which involves various type of generation. We introduce the global optimization approach to coordinate the thermal type, hydro type and pumped storage type generation. To overcome the shortcomings in dynamic programming for thermal unit commitment, an improved heurisitic method using lambda(λ) was proposed, Hydro and pumped type allocation was Solved by analytical approach using λ which exculde undisirable iteration for satisfying the energy usage constraints. The case studies for proposed algorithm are proven by sample system and KEPCO practical system, which produced very resonable both computing requirements and convergency.

• Proceedings of the KIEE Conference
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• 1993.07a
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• pp.192-194
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• 1993

This paper presents an efficient method for determining the economic dispatch of thermal generator using an alternative Jacobian matrix considering system constraints. The transmission loss is approximately expressed as a funtion of generating powers and the generalized generation factor. From this expression, the Jacobian matrix is formulated and solved by the Newton Raphson Method. In this method, the economic dispatch problem is solved rapidly without calculating the penalty factor. The proposed method has fast convergency characteristic and good accuracy. The feasibility of this method is demonstrated by means of examples.

• The Journal of Information Systems
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• v.26 no.2
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• pp.123-142
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• 2017

Purpose The development of the Fintech industry can be on the basis of the development in IT technologies such as Big data, IoT, cloud computing, it can be considered that the financial industry is repeating the evolution into Fintech. But the awareness of the consumers is still very low. Therefore the current dissertation, tries to deduce the suggestions for invigoration measures for Fintech by conducting an empirical study on the factors that influence the intention of reuse of Fintech on the consumer's point of view. Design/methodology/approach This study made a design of the research model by integrating the factors deducted from the Expectation Confirmation Theory. This paper empirically analyzes the impact of Continuous Usage Intention for Improvement of Fintech. The 302 survey responses were used to verify research hypotheses through covariate structural equation model. Findings According to the empirical analysis result, this study confirmed that the ultimate purpose of the Fintech service is to eliminate the social cost's waste element occurring from issue of money by not using or reducing the usage of cash. Since many Fintech users have pointed out security as the priority task, a direction for the related institutions has been proposed. Second, the content of the current dissertation will be the opportunity of broadening the perception of the current consumers that perceive Fintech as only a NFC simple payment service.

• Horticultural Science & Technology
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• v.30 no.3
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• pp.308-324
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• 2012

The aim of this study is to develop and construct the elements of a new evaluation tool to assess the effectiveness of a horticultural therapy. Delphi method was applied to classify the realms of evaluation and specify their components and constituting items. Delphi process was performed through three rounds and 24 professionals attended all the rounds as panel members. Some of the items were revised or removed according to the results of such tests as content validity ratio, agreement rate, convergency and stability of each item. On the contrary, a few new items were added by accepting the opinions of the professional panels. Previous to the Delphi, the realms of evaluation were classified into physical, cognitional, psycho-emotional and social ones on the basis of literature review, professionals' consultation and in-depth interview with practitioners. At the first round, 112 items constituting four realms were reviewed. The numbers of items to be reviewed were reduced to 107 at the second round and to 102 at the third round. As a result, 98 items in 4 realms were decided as proper evaluation points of horticultural therapy. The compositions of the four respective realms are as follows: 5 components and 27 items in physical realm; 4 components and 25 items in cognitional realm; 2 components and 24 items in psycho-emotional realm; and 4 components and 22 items in social realm. These realms, components and specific items derived from this study constitute indices to evaluate the effectiveness of horticultural therapy. In addition, they might be utilized as good guidelines for planning horticultural therapy programs.

• Journal of the Korea Society of Computer and Information
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• v.15 no.9
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• pp.77-85
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• 2010

As various convergency products have been actively developed, the study on user interface has been conducted a lot, and for more specific direction, users' experience-oriented user interface from user-oriented studies is recently developed. Such a tendency aiming to focus on product development to express users' emotion, the next step in the user-oriented development had difficulties in an objective approach, so the data based on previous users' experiences were presented as the basic data to establish user interface design process with grounds and design direction, and therefore it is available to show more specific and objective grounds. From this perspective, such psychological variables showing users' experiences like age and job are studied through surveys of users at the development of products, and products according to the variables are released. On the other hand, the products considering psychological difference distinguishing users' experiences as the cultural cap are not progressed yet. Despite the understanding of cultural difference, its decisive grounds are hard to distinguish like age, and job. Therefore, the cognitive concept about how to design menu information structure according to accident types that can be considered regarding user interface design among theoretical backgrounds about cultural difference. As the category according to the range of things among accident types, it is divided into analytical type and relational type to conduct a test on similarity and relations about the representative digital TV's menu information of the convergency product. As the result, analytical type and relational type showed difference and this study aims to use menu information concept considering this difference as explanatory variables of the users' experience-oriented development.

• Journal of Digital Convergence
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• v.11 no.4
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• pp.321-330
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• 2013

Lately, in accordance with the improvement of living standards and income level, concern about the health is continuously increasing and the desire is also becoming diverse. This study focused on the user's acceptance of converged smart u-health system. For the study purpose, this paper analyzed the health and technology factors influencing the user's acceptance on u-health system. Thus this study was carried out by using covariance based SEM in order to test the model fitness and path coefficient. As the results, the health management experience among HPM factors and perceived usefulness among TAM had a positive effect on attitude and the perceived usefulness had a direct effect on behavioral intention.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.6
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• pp.125-130
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• 2014

In recent years, the IT conversions have rapidly developed along the development of the information technologies and devices. The overuse of IT devices caused by this trend has weakened the physical condition of children these days, compared to the past, therefore a study for this problem is necessary. This study intends to improve the health of children, easy to lack physical activities caused by the addiction to PC and smart phones, by proposing a health care application for them using Kinect. This application will introduce some simple aerobic/anaerobic exercises that could be done in home and will help children to forget the boredom by exercising alone and to coach them by using it.

• Structural Engineering and Mechanics
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• v.36 no.3
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• pp.247-278
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• 2010

The study of the seismic vulnerability of masonry buildings requires structural properties of walls such as stiffness, ultimate load capacity, etc. In this article, a method is suggested for modeling the masonry walls under in-plane loading. At the outset, a set of analytical equations was established for determining the elastic properties of an equivalent homogeneous material of masonry. The results for homogenized unreinforced brick walls through detailed modeling were compared in different manners such as solid and perforated walls, in-plane and out-of-plane loading, etc, and it was found that this method provides suitable accuracy in estimation of the wall linear properties. Furthermore, comparison of the results of proposed modeling with experimental out coming indicated that this model considers the non linear properties of the wall such as failure pattern, performance curve and ultimate strength, and would be appropriate to establish a parametric study on those prone factors. The proposed model is complicated; therefore, efforts need to be made in order to overcome the convergency problems which will be included in this study. The nonlinear model is basically semi-macro but through a series of actions, it can be simplified to a macro model.

• The Journal of Information Systems
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• v.29 no.2
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• pp.51-69
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• 2020

Purpose Today, the increasing of internet use and the expansion of internet range provide us with many opportunities. Therefore, this study examine relation of perceived ease of use, perceived playfulness, perceived risk, perceived usefulness based on previous studies. And we examine the effect of O2O service satisfaction on continuous use intention. Also, we studied the relationship between perceived ease of use, perceived playfulness, perceived risk, perceived usefulness according to user innovation. Design/Methodology A Structural Equation Model(SEM) method was used to test the theoretical framework based on a sample of 451 respondents who have experienced the O2O service. Factor analysis and confirmation factor analysis was conducted to check the reliability, convergency validity and discriminant validity. To test moderating effect of the user innovation, multi group analysis was conducted. Findings First, perceived ease of use, perceived playfulness, perceived risk have significant effects on perceived usefulness. Second, perceived usefulness of O2O service have a positive effect on satisfaction. Third, satisfaction of O2O service have a positive effect on continuous use intention. The relationship that perceived ease of use, perceived playfulness, perceived risk affect perceived usefulness is differ depending on user innovation. Based on these findings, this study suggested to marketing practitioners the need for different approach by a user innovation.

• Journal of the Society of Disaster Information
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• v.14 no.1
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• pp.43-50
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• 2018

This study presented 3D Finite Element (FE) analysis of curved beam structures subjected to static and dynamic loading conditions, which is particularly strong ground motions. It was shown that the results obtained from 3D FE analyses was similar to the theoretical solution within 1% convergency error, in order to validate the 3D solid FE models in this study. In particular, it was focusing on development of dynamic characteristics of curved beam structures subjected to three-different seismic ground motions: GyeongJu, Lomaprieta and Northridge earthquakes. Consequently, It was interesting to find that the results obtained from GyeongJu earthquake was detuned due to high frequency effect, but the Von-Mises of the curved beam structure under Lomaprieta earthquake was 647.824 MPa at 45 curvature degree.