• Proceedings of the Korean Geotechical Society Conference
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• 1991.10a
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• pp.289-311
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• 1991

Analysis of supported excavation system by Elasto-Plastic Isoparametric Finite Element Method and Elasto-Plastic Beam Method have been conducted for the simulation of stepwise underground excavation. Conventional methods, fixed Supported Beam and Spring Supported Beam method, also have been examined and compared with the results of elasto-plastic beam method and field data. Except unavoidable result of upward ground settlement near the top of retaining wall and relatively high bending moment of wall at each excavation level, satisfactory results have been derived using elasto-plastic isopara metric finite element method. The results from elasto-plastic beam analysis program, developed by the author, are proved to be fit field data in acceptable variance as shown in the paper. Displacement and bending moment, of the wall by conventional methods, both fixed supported beam and spring supported beam, are always underestimated than field data, and attention must be given that the diffence increases with deeper excavation depth and lower horizontal subgrade reaction of the ground.

• Journal of Korean Academy of Nursing
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• v.28 no.3
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• pp.563-572
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• 1998

The purpose of study was to develop and validate Korean Sleep Scale A which can be easily administrated by nurses for a wide range of adult subjects. Dimensions of sleep concept were derived by literature review. Previously developed sleep sclaes were also analyzed in order to develop scale items. The Korean sleep scale A was structured as a 15 item, 4 point likert type scale. The Scale was tested an 298 female and male adult subjects after pilottest and content validation. The results showed reliability by internal consistency of Cronbach's α=.75 Construct validity was tested by factor analysis and known group technique. Factor analysis showed 4 factors-sleep pattern, sleep evaluation, sleep result, and cause of sleep disturbance. These four factors explained 55.9% of total variance. Correlations between factors ranged from .15-.32. There was correlation among Korean Sleep ScaleA score, Verran and Snyder-Halpern(VSH) Sleep Scale score, and sleep satisfaction scale score, r=.71(p=.00), r=.51(p=.03), respectively, These study results partially support reliability, construct validity, and criterion related validity of Korean Sleep Scale A. Further validation study is required with other subjects and other settings.

• Proceedings of the Korea Hospitality Industry Research Society Conference
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• 2005.11a
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• pp.21-33
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• 2005

This study investigated of the differences of the image between the domestic and china tourist of the visiting in busan metropolitan city and their image evaluation were different according to the nationality. The attribute for the destination image types were measured using 27 items. The factors involved in the destination image were analysis and 7 factors emerged. The result are as follows. First, Between the domestic and china tourist of living appeared to statistical different of the destination image. Second, Between destination image and revisiting preference appeared to statistical difference. Third, Between destination image and revisiting preference appeared to statistical difference according to the nationality. Forth, Between destination image and revisiting preference appeared to statistical partially difference according to the nationality. Finally it is also appeared to the statistical difference on the job. ANOVA, t-test was utilized for the above analysis which revealed that a statistic partially difference exited between domestic and china tourist.

• Journal of Technology Innovation
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• v.8 no.2
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• pp.67-96
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• 2000

This study aims to provide information about the priority setting and budget coordination of government R&D spendings in Korea. Based on the result of "survey, analysis and evaluation of national R&D programs" in FY 1999, this paper reviews the government R&D expenditures by concerned variables such as program objectives, sector of performance, character of work and technology fields. This paper also carries out an analysis on the government R&D supports as ways for the promotions of high technology-based start-ups and SMEs and regional innovation activities. It is found that relatively high investment is made in the industrial technology areas and development research, and there are some redundancies of R&D programs among ministries and agencies in terms of technology fields, program objectives and character of work. Policy implications and future research directions are suggested.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.8
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• pp.140-150
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• 2000

In this paper module of a product is determined by the characteristics of a product itself and process. To analyze the characteristics of the product information on subassemblies and parts can be obtained by analyzing the existing product. Based on the analysis of characteristics of product structure and function determination rules of a module degree could be proposed for assembly and disassembly process and product structure and function. By applying these rules of a module, module of a product is classified into full half and non-module depending on the module degree of a product. As a result of module degree analysis simpler assembly process and reduced structural interference can be realized. For the product function simpler updated and multi function can be also achieved.

• Progress in Superconductivity and Cryogenics
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• v.24 no.4
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• pp.78-83
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• 2022

REBCO coated conductors are widely used for HTS power application, high magnetic field magnet application, and etc. A thermal stability of the REBCO conductor is essential for the operation of HTS-based device, and thermal conductivities of the conductor are relevant parameters for modeling cryogenic heat transfer. REBCO conductors consist of a REBCO layer, copper layers for electrical stabilization and a hastelloy substrate. At cryogenic temperature, thermal conductivity of copper and silver strongly depend on the purity of the material and the intensity of the magnetic field. In this study, thermal conductivities of the laminated composite structure of REBCO conductor are evaluated by using the thermal network model and the multidimensional heat conduction analysis. As a result, the thermal network model is applicable to REBCO conductors configured in series or parallel alone and multidimensional heat conduction analysis is necessary for complex cases of series and parallel configuration.

• Journal of Korea Multimedia Society
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• v.24 no.9
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• pp.1224-1241
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• 2021

Recent development of deep learning techniques for image generation has led to straightforward generation of sophisticated deepfakes. However, as a result, privacy violations through deepfakes has also became increased. To solve this issue, a number of techniques for deepfake detection have been proposed, which are mainly focused on RGB channel-based analysis. Although existing studies have suggested the effectiveness of other color model-based analysis (i.e., Grayscale), their effectiveness has not been quantitatively validated yet. Thus, in this paper, we compare the effectiveness of Grayscale channel-based analysis with RGB channel-based analysis in deepfake detection. Based on the selected CNN-based models and deepfake datasets, we measured the performance of each color model-based analysis in terms of accuracy and time. The evaluation results confirmed that Grayscale channel-based analysis performs better than RGB-channel analysis in several cases.

• Journal of Energy Engineering
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• v.29 no.3
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• pp.91-96
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• 2020

For the anchor bolts and brackets that fix the stone wall, which is an external finishing material, it is necessary to maintain the performance required for the mechanical structure from the initial design stage and secure high durability. For this, the design and safety evaluation in consideration of the load conditions are necessary, so the structural analysis applying the finite element analysis technique was performed as a method to verify durability. As a result of structural analysis for various shapes for optimal design, a reinforcing structure was added to alleviate the maximum stress generated at the rear part of the bracket in contact with the bolt. In addition, a reinforcing plate was additionally attached to the bracket to relieve the stress concentration of the L-shaped bracket to make the stress distribution uniform, so that the safety factor satisfies the standard conditions. In addition, the fatigue life analysis by cyclic load was performed, and the fatigue safety factor was analyzed. As a result, the durability was obtained.

• New & Renewable Energy
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• v.16 no.1
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• pp.1-14
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• 2020

Liquid air energy storage (LAES) using gas liquefaction has attracted considerable attention because of its mature technology, high energy density, few geographical constraints, and long life span. On the other hand, LAES has not yet been commercialized and is being developed recently. Therefore, few studies have performed an economic analysis of LAES. In this study, the levelized cost of electricity was calculated and compared with that of other energy storage systems. As a result, the levelized cost of electricity of LAES was $371/MWh. This is approximately $292/MWh, $159/MWh, $118/MWh, and $3/MWh less than that of the LiCd battery, VRFB battery, Lead-acid battery, and NaS battery. In addition, the cost was approximately $62/MWh and $195/MWh more than that of Fe-Cr flow battery and PHS. Sensitivity analysis of the levelized cost of electricity according to the main economic factors was performed, and economic uncertainty analysis was performed through a Monte-Carlo simulation. The cumulative probability curve showed the levelized cost of electricity of LAES, reflecting price fluctuations in the air compressor cost, electricity cost, and standing reserve hourly fee.

• The Korean Journal of Community Living Science
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• v.27 no.spc
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• pp.689-702
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• 2016

In this study, it was promoted for the purpose of direction for rural landscape planning and management through the analysis of the factors of change in the rural landscape. In the course of research, through literature review study and field surveys, to derive the 25 factors that influence the change in the rural landscape. Later, 25 factors were evaluated in the impact on landscape by experts. 25 factors of the rural landscape were a comprehensive analysis and the results of literature review study and field surveys about the five villages of research area; Ji-San village, Non-Gae village, etc. Expert evaluation was carried out by the rural landscape, and architecture professionals of various related fields. As a result of the analysis, the flow of rural development policy and the business had a great effect on the physical changes in the rural landscape. Furthermore, additional factors such as population structure and lifestyle have made the change in the complex landscapes. Meaning the study has is to provide information on what need there are considered factors in the rural landscape planning and management. The reason is that, since the rural landscape characteristics are different, in order to develop the more efficient rural landscape plan and management.