• Journal of the Korean Geotechnical Society
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• v.24 no.1
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• pp.37-49
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• 2008

A geothermal heat pump system is a preferable alternative energy system in Korea because it uses the heat energy of the earth, which is environmentally friendly and inexhaustible. In order to characterize the thermal conductivity and viscosity of grout materials used for backfilling ground heat exchangers, nine bentonite grouts, one marine clay from Boryung, and cement grouts adapted in the United State have been considered in this study. The bentonite grouts indicate that the thermal conductivity and viscosity increase with the content of bentonite or filler (silica sand). In addition, material segregation can be observed when the viscosity of grout is relatively low. The marine clay turns out to be unsuitable for backfilling the ground heat exchanger due to its insufficient swelling potential. The saturated cement grouts appear to possess much higher thermal conductivity than the saturated bentonite grouts, and the reduction of thermal conductivity in the cement grouts after drying specimens is less than that in the case of the bentonite grouts. Maintaining the moisture content of grouts is a crucial factor in enhancing the efficiency of ground heat exchangers.

• Journal of the Korean Geotechnical Society
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• v.22 no.5
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• pp.59-67
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• 2006

The centrifuge and 1-g shaking table tests were performed simultaneously to compare the dynamic behaviors of loose sands of the same geotechnical properties. The prototype soils were 10 m thick liquefiable loose sands. The geometric scaling factors were 20 for 1-g and 40 for centrifuge tests. The excess pore pressure, surface settlement, and acceleration in the soil were measured at the same locations in the 1-g and centrifuge tests. The total excess pore pressure from development to dissipation was measured. In the centrifuge test, viscous fluid was used as the pore water to eliminate the time scaling difference between dynamic time and dissipation time. In the 1-g tests, the steady state concept was applied to determine the unit weight of the model soil, and two different time scaling factors were applied for the dynamic time and the dissipation time. It is concluded that the 1-g tests can simulate the excess pore pressure of the prototype soil if the permeability of the model soil is small enough to prevent dissipation of excess pore pressure during shaking and the dissipation time scaling factor is properly determined.

• Journal of the Korean Geotechnical Society
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• v.26 no.7
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• pp.161-170
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• 2010

For the development of load and resistance factor design, reliability analysis is required to calibrate resistance factors in the framework of reliability theory. The distribution of measured-to-predicted pile resistance ratio was obrained based on only the results of load tests conducted to failure for the assessment of uncertainty regarding pile resistance and used in the conventional reliability analysis. In other words, successful pile load test (piles resisted twice their design loads without failure) results were discarded, and therefore, were not reflected in the reliability analysis. In this paper, a new systematic method based on Bayesian theory is used to update reliability indices of driven steel pipe piles by adding more proof pile load test results, even not conducted to failure, to the prior distribution of pile resistance ratio. Fifty seven static pile load tests performed to failure in Korea were compiled for the construction of prior distribution of pile resistance ratio. The empirical method proposed by Meyerhof is used to calculate the predicted pile resistance. Reliability analyses were performed using the updated distribution of pile resistance ratio. The challenge of this study is that the distribution updates of pile resistance ratio are possible using the load test results even not conducted to failure, and that Bayesian updates are most effective when limited data are available for reliability analysis.

• Knowledge Management Research
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• v.23 no.4
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• pp.207-231
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• 2022

The purpose of this study is to identify the relationship between PJF(person-job fit) and members' organizational commitment focusing on the mediating factor. Previous Studies have found that person-job fit has positive effect on organizational commitment, and self-efficacy has positive effect on the organizational commitment. On the other hand, the studies to identify whether self-efficacy has a role in mediation between PJF and the members' organizational commitment has been insufficient. To that end, we considered self-efficacy as the mediator of the relationship between PJF and organizational commitment. We used the data which to perform national policy research from 690 workers at a small or medium firm. As a result of verifying the suitability of the research model, it was suitable for the acceptance criteria. Besides the hierarchical regression analysis, bootstrapping was conducted to verify significance of mediating effect of self-efficacy. The main results are as follows. First, the variables, PJF, self-efficacy and organizational commitment showed a positive correlation. Second, PJF has a positive effect on self-efficacy and organizational commitment significantly. Also self-efficacy has a positive effect on organizational commitment significantly. Third, the mediating effect of self-efficacy in the relationship between PJF and organizational commitment is significant. In order to improve person-job fit, this study suggested that SMEs' owners should consider job rotation system and career development program for employees. Based on this study result and implications, we discussed limit of research and direction for future research.

• Journal of Digital Convergence
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• v.20 no.1
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• pp.129-139
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• 2022

This study aims to identify which factors affect successful big data system construction, identify the relationship between the factors, and identify the success model and success factors necessary for public institutions to build big data systems. Therefore, the preceding and related studies related to this study were reviewed, and success factors for the establishment of a big data system were derived based on this. As a research method, a survey was conducted on users of institutions that have established or planned to build a big data system, and a structural equation (AMOS) was conducted to verify the impact relationship between success factors. As a result of the analysis, organizational support factors, development support factors, user support factors, information quality, service quality, system quality, use, and net benefit were derived as success factors for building big data systems, and a success model was presented. This can be seen as significant and academic contributions in that it is the first study of the success model for building an information system reflecting big data characteristics, and it is expected that this study will be used as basic data for building a big data system in public institutions in the future.

• Journal of Cadastre & Land InformatiX
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• v.52 no.2
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• pp.121-135
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• 2022

The purpose of this study is to explore the convergence sector of the spatial information industry based on the business transaction data of spatial information companies and to predict the market size of the industry using the Seemingly Unrelated Regression(SUR) model. The convergence part of spatial information industry, which cannot be identified in the Spatial Data Industry Survey, was analyzed by exploring keywords related to spatial information using the business DB of Korea Enterprise Data (2010-2019). The convergence of spatial information businesses mainly appeared in the business relationship between the value chain between Seoul and Gyeonggi Province. The convergence business has the largest sales in the value chain 2 (utilization, service) & 3 (convergence), and also the convergence in the value chain 1 (production, construction) & 2, 2 & 3 stages has doubled in 2019 compared to 2010. In 2019, the total sales of the spatial information industry based on the Statistical Korea were announced at about 8 trillion won, but in this study, the total sales of the spatial information industry were estimated at 28 trillion won considering convergence activities. Finally, when scenario 1 (0.38% population growth, 2020-2024) and 0.07% (2026-2030) were applied using the SUR model to predict the expected market size of the industry, sales decreased by -0.37% to 0.069% in 2025 and 2030 by respectively. When scenario 2 (average wage growth 1.2%) was applied during the same period, sales in the industry increased by 2.326% to 12.185%. In other words, the sales in the spatial information industry depends on Labor, Total Factor Productivity, and Capital Productivity so it is necessary to additional research on policy development and alternatives of enhancing each productivity.

• Journal of Embryo Transfer
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• v.16 no.3
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• pp.223-231
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• 2001

The success of nuclear transplantation with mammalian oocytes depends critically on the potential of oocytes activation, which mainly caused to prevent the re-accumulation of maturation promoting factor (MPF). This study was conducted to compare the effect of combined treatment of lonomycin with a Hl-histone kinase inhibitor (dimethylaminopurine, DMAP) or cdc2 kinase inhibitor (sodium pyrophosphate, SPP) on activation of bovine oocytes. In vitro matured bovine oocytes with the first polar body (PB) and dense cytoplasm were assigned to 3 experimental groups. For activation treatment, oocytcs were exposed to 5 $\mu$M lonomycin for 5 min (Group 1), and followed by 1.9 mM dimethylaminopurine (DMAP) for 3 h (Group 2) or followed by 2 mM sodium pyrophosphate (SPP) for 3 h (Group 3). The activation effects in the three treatments and the control group (untreated) were judged by the extrusion of the second PB and formation of a pronucleus (PN). Differences among groups were analysed using one-way ANOVA after arc-sine transformation of proportional data. All three treatments led to high activation rates (90% to 95%), with significant difference from the control. However, the extrusion of the second PB and the rate of PN formation differed remarkably among treatments. In Group I and 3, about 95% of the oocytes had extruded the second polar body, but one PN had formed in a higher proportion of oocytes in Group 3 than in Group 1 (90% vs. 5%). In experiment 2, the rates of cleavage and development into blastocysts in Group 1 were significantly lower than those of Group 2 and 3 (8.7% and 0% vs. 50.5% and 11.6%, and 44.6% and 7.2%, respectively, P<0.05). In experiment 3, ~80% of parthenotes in Group 1 were developed with haploid chromosomal sets. However, when ionomycin was followed immediately by DMAP (Group 2). only 20% of parthenotes were haploid. In Group 3, combined treatment with ionomycin and SPP, the appearance of abnormal chromosomal tracts was significantly (P〈0.05) reduced and the proportion of haploid parthenotes was increased to 85% (17/20) than in Group 2. These results demonstrate that SPP acted as a cdc2 kinase inhibitor and formed the haploidy in oocyte activation. Thus, the present study suggests that cdc2 kinase inhibitor, such as sodium pyrophosphate, may have an effective role in oocyte activation for the production of cloned embryos/animals by nuclear transplantation.

• Journal of Digital Convergence
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• v.20 no.3
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• pp.41-52
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• 2022

Although domestic public libraries achieved quantitative growth based on the 1st and 2nd comprehensive library development plans, there were some qualitative shortcomings, and various studies have been conducted to improve them. Most of the preceding studies have limitations in that they are limited to social and economic factors and statistical analysis. Therefore, in this study, by applying the spatiotemporal concept to quantitatively calculate the decrease in public library loan demand due to rainfall and heatwave, by clustering areas with high demand for book loan due to weather changes and areas where it is not, factors inside and outside public libraries and After the combination, changes in public library loan demand according to weather changes were analyzed. As a result of the analysis, there was a difference in the decrease due to the weather for each public library, and it was found that there were some differences depending on the characteristics and spatial location of the public library. Also, when the temperature was over 35℃, the decrease in book loan demand increased significantly. As internal factors, the number of seats, the number of books, and area were derived. As external factors, the public library access ramp, cafe, reading room, floating population in their teens, and floating population of women in their 30s/40s were analyzed as important variables. The results of this analysis are judged to contribute to the establishment of policies to promote the use of public libraries in consideration of the weather in a specific season, and also suggested limitations of the study.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.7
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• pp.267-278
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• 2017

The aim of this paper was to develop a scale for measuring gender identity among sports participants (114 male, 193 female). Gender similarities and latent mean analysis was used to validate the gender identity measurement method. Data processing was carried out by way of frequency analysis, exploratory and confirmatory factor analysis, reliability, correlation, normal distribution of questions, and latent mean analysis using SPSS 18.0 and AMOS 18.0. The results of this study were as follows: First, the equivalence had revealed the configurable, metric, and scalar invariance of the scale that can be used in multi-groups in the same way. Second, women had a more open inclination than men when it came to participating in sports activities (p<.001). Third, women participating in sports activities tended to be more conservative than men (p<.001). Fourth, women who participated in sports activities showed a higher subjective tendency than men (p<.001). Fifth, there was no statistical difference in the outward tendency when participating in sports activities (p<.05). The results of this study suggest that gender identity among sports participants is not influenced by the changing times and the advancement of women in society.

• Korea Science and Art Forum
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• v.27
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• pp.101-114
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• 2017

Based on the relationship between urban public space, urban lighting and the sense of place, this paper aims to analyze the lighting environment types with the sense of place and their characteristics. First, with the theory study as the research foundation, it extracts six spatial factors of public space lighting design and then analyzes 12 relevant cases on the basis. Finally, it divides the 12 cases into four types, Basic types, Storytelling, Interactive and Multi-Media and analyzes the core design factor and characteristics of various types. The results show that: first, functionality, sustainability and aesthetics are the basic factors to realize the urban public space lighting places. Second, the six cases of "Storytelling" show that the theme of specific areas, namely the exploration of "story" is conducive for lighting design to form clear and definite environment recognition. Third, for "Interactive" and "Multi-Media", the intervention of new media technology and new lighting way has made the wide expansion of urban lighting design connotation and extension. The research results show that strengthening the urban location performance by the lighting design could improve the city image, which provides the basis for the development of urban public space lighting design.