• Proceedings of the Korea Society for Industrial Systems Conference
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• 2008.10b
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• pp.404-428
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• 2008

기대일치이론에 기초한 기대일치모형은 정보시스템 연구 분야에서 정보시스템의 지속적인 사용 혹은 사용의도를 설명하는 핵심 이론으로 언급되어 왔다. 이러한 기대일치모형과 더불어 최근에 정보시스템 분야에서 주목을 받고 있는 또 다른 개념은 자동화된 행동 경향을 의미하는 ‘습관’이다. 본 연구에서는 이러한 두 가지 개념들을 기초로 모바일 인터넷 서비스에 대한 지속적인 이용 상황에서 습관과 기대일치모형을 통합하는 시도를 하였다. 이에 일치, 지각된 유용성, 지각된 사용 용이성, 습관 등의 수용후 신념, 이용자 만족, 지속적 이용의도로 구성된 연구모형을 구성하고 이를 검증하였다. J도내 250명의 대학생들을 대상으로 설문자료를 수집하여 분석한 결과, 기대일치와 지각된 유용성이 모바일 인터넷 서비스의 이용자 만족에 대한 주요 요인으로서 나타났다. 또한 지각된 유용성, 이용자 만족, 습관은 모바일 인터넷 서비스에 대한 지속적 이용의도를 결정하는 주요 요인으로 나타났다. 반면에 지각된 이용 용이성은 이용자 만족과 지속적 이용의도 모두에 대하여 아무런 관련성이 없는 것으로 나타났다.

• Survey Research
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• v.5 no.1
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• pp.1-26
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• 2004

The aim of this study lies in answering the question "How to form weighting cells to enhance sample representativeness in telephone, Internet and mobile surveys\ulcorner". For this, we explored 2% raw data of Year 2000 Population and Housing Census of Korea looking for meaningful patterns for ownership of telephones, the usage of Internet and/or mobile phones. We found that telephone coverage rates vary significantly by household size; 84.6% for one member households, contrasting 98.5% for two-or-more member households. Thus, telephone survey samples need to be weighted differently in sub-groups by household size for proportional representation of target population. Searching socio-demographic factors influencing the use of Internet by C5.0 tree models, we found that education levels and the occupation (or housing type, the automobile ownership) are two most important factors in addition to gender and age. Thus, surveyor might form weighting cells by such factors at the stage of post-stratification or set quotas, a priori, proportional to size of the cells by such factors. For mobile surveys, we approached similarly and found that education levels and the occupation (or the automobile ownership, marriage status) are two additional factors that may be used in forming weighing cells or in setting quotas for cells.

• KIEAE Journal
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• v.16 no.2
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• pp.23-31
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• 2016

Purpose: Recently energy consumption is rapidly increasing due to continuous development of social evolution in various field. In this situation, there is a lot of effort to reduce this energy consumption in many ways, especially in building energy. Preceding studies already started to analyze the housing area such as zero energy house and passive house by researching annual building energy consumption, but to apply the results of housing to office building is insufficient since it has different consumption tendency. Method: In this study, eQuest program was used for simulation and the base model is selected among standard office building in ASHRAE 90.1. Variables are divided into passive and active factors for comparison. Result: In passive factors, glazing system showed the highest energy saving rate by 21.3% with triple low-e glass and enhancing wall u-value showed the lowest energy saving rate by 3.6% with 0.15 m2/K. In active factors, VAV system showed 30.9% energy saving rate when compared to CAV system, and heat exchanger showed 10.2% energy saving rate. For regeneration energy part, photovoltaic panel generated 10.4% of base annual energy usage.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.10B
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• pp.1004-1012
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• 2009

Although it is raising expectation of multimedia multicast services in various wireless networks, it requires an efficient IP multicast group membership management in wireless environment. However, the existing IGMPv3/MLDv2 protocols are too heavy; they are not suitable for wireless environment. Moreover they suffer from a number of problems, such as unreliable signaling, slow state transition, low spectral efficiency, bulk report, and interrupting dormant receivers. In this paper, we propose a wireless host agent (WHA)-based IP multicast group management scheme that requires a reduced number of signaling, which also solves such problems effectively. We develop an analytic model to quantify costs of bandwidth usage and signaling overhead, and perform comparison and analysis of the proposed scheme.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.4
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• pp.582-591
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• 2000

In this paper, the Finite-Difference Time-Domain(FDTD) modeling method of the Korean human head is introduced to calculate electromagnetic energy absorption for the human head by mobile phones. After MRI scanning data is obtained, 2 dimensional(2D) segmentation is done from the 2D MRI image data by the semi-automatic method. Then, 3D dense segmentation data with $1mm\times1mm\times1mm$ is constructed from the 2D segmentation data. Using the 3D segmentation data, coarse FDTD models of human head that is tilted arbitrarily to model the condition of tilted usage of mobile phone.

• Lingua Humanitatis
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• v.5
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• pp.127-163
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• 2003

This thesis analyzes the Chapter "Hoyeonjigi(浩然之氣)" of Mencius(孟子), using text linguistics theory and reading theory of Korean. In this process the model of macro-structure #1∼5 are presented, according to Vandijk′s rules of macro-structure; Auslassen, Selektierne, Generalisieren, Konstruieren odor Integrieren. As a result, this certifies; First, macro-structure could make arbitrarily a several steps of macro-structure by types of text or purpose of analysis. Second, macro-structure applies various cognitive mechanisms of outer world as well as inner world. Third, a text with profound symbolism could be figured as a two-or threefolded symbolic structure. At the same time, macro-structure enables the clearer analysis of the content of the Chapter to verify the following; first, Hoyeinjigi itself is the best measure of developing "Imperturbable Mind(不動心)" Second, benevolence-righteousness(仁義) and wisdom(智) would be reached by cultivating Hoyeonjigi. Third, Mencius′ own view of language is well expressed in "Jieon(知言)", which is not only a condition for Imperturbable Mind, but also the Oriental view of language focused especially on listening in terms of language usage, not language analysis. This Mencius′ view of language has a thread connection with that of Oriental′s.

• Structural Engineering and Mechanics
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• v.41 no.4
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• pp.509-525
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• 2012

In recent years, CFRP material usage in strengthening applications gradually became widespread. Especially, the studies on the strengthening of shear deficient reinforced concrete beams with CFRP strips are chosen as a subject to numerous experimental studies and research on this subject are increased rapidly. The most important variable, that is affected on the failure mode of CFRP strips and that is needed for determining the shear capacity of the strengthened reinforced concrete beams, is the strain distribution between CFRP strips and concrete. Numerous experimental studies are encountered in the literature about the determination of strain distribution between CFRP strips and concrete. However, these studies mainly focused on the CFRP strips under axial tension. There are very limited numbers of experimental and analytic studies examining the strain distribution between concrete and CFRP strips, which are under combined stresses due to the effects of shear force and bending moment. For this reason, existing experimental study in the literature is used as model for ANSYS finite element software. Nonlinear finite element analysis of RC beams strengthened against shear with CFRP strips under reverse cyclic loading is performed. The strain distributions between CFRP strips and concrete that is obtained from finite element analysis are compared with the results of experimental measurements. It is seen that the experimental results are consisted with the results derived from the finite element analysis and important findings on the strain distribution profile are reached by obtaining strain values of many points using finite element method.

• International Journal of Naval Architecture and Ocean Engineering
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• v.9 no.5
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• pp.568-576
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• 2017

With an increase in the usage of LNG, there is a heightened interest about its safety aspects regarding the explosion of LNG carrier tank. The need for a cryogenic explosion-proof camera has increased. The camera has to work in cryogenic environment (below $-160^{\circ}C$) in LNG carrier. This study conducted design and heat transfer analysis of cryogenic camera to secure working time in limitation of heat source. The design with gap width of double pane windows was conducted based on simple vertical cavity model to insulate from cryogenic environment. The optimal gap width was 12.5 mm. For effective analysis considering convection within the camera, equivalent thermal conductivity method was adopted with ABAQUS. The working time of the camera predicted was over 10 h at warm-start condition. In cold-start condition, it required about 5 h of pre-warming time to work. The results of analysis were compared with the ones of the actual cryogenic test.

• Journal of the Korea Society for Simulation
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• v.17 no.4
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• pp.143-152
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• 2008

At an initial battle stage, counter-fire capability have critical impact on defeating the enemy in the future warfare. In this paper, we proposed an efficient method of counter-fire execution. To do that, hit-probability for each artillery type was evaluated using CEP and applied to calculate new target reference table of a counter-fire operation. In order to compare new result to the one obtained by using previous reference table from BTCS, we did simulation using MANA model. Simulation outputs show that new method is superior to previous method of counter-fire operation in various scenarios depending upon each method and usage of UAV.

• Korean Journal of Computational Design and Engineering
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• v.16 no.2
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• pp.137-145
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• 2011

A variety of BIM libraries are required to apply BIM(Building Information Modeling) software and generate BIM data. However, enterprises are establishing their own libraries using BIM tools, the drawbacks are that these libraries are not open to other users, or they just can be used in some software packages. If IFC(Industry Foundation Classes), the standard format of open BIM, can be applied, the BIM library can be applied in all the BIM software packages. Although the enterprises can collaborate using IFC standard, it is difficult to represent all the property information of the construction materials by IFC. IFD(International Framework for Dictionaries) is used to solve these problems and add the property information of the construction materials easily. Therefore, Open RIM-based library needs to be developed using IFD. In this research, the development and application of BIM library and IFD in domestic and foreign countries were investigated and analyzed, and Open BIM-based IFD scenario was proposed for using, and finally by applying an IFD method, the IFD data was added within an IFC model. Consequently, Open BIM-based library can be extended with rich, formal, and semantic descriptions and enhance data interoperability among BIM software packages adopting Open BIM standard format, by applying the IFD.