• Economic and Environmental Geology
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• v.35 no.5
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• pp.455-463
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• 2002

There have been few geophysical studies on the crustal structure of the continent-ocean zone around the middle eastern part of Korean peninsula, because of the lack of database in both land and ocean. The area for the study on the internal crustal structure using gravity data is bounded by the latitude of 37$^{\circ}$-38"N and longitude of 128$^{\circ}$-132$^{\circ}$E. WCA correction is applied to shipborne gravity data to integrate with gravity anomalies obtained on land. The high frequency components of the shipborne gravity data which are considered as the noise on survey track are effectively removed by means of correlating with satellite gravity data. The corrected shipborne free-air gravity anomaly is integrated with the Bouguer gravity anomaly on land under the same condition. The integrated gravity anomaly is divided into four areas for power spectrum analysis. The depths of Moho discontinuity increases gradually from inland to Ulleung basin. As the result of modeling based on power spectrum analysis, Moho discontinuity depth is about 33-35 km in the continental zone of Korea and 18-28 km at the continental margin. Such structural character is well elucidated in changing gravity data around Ulleung basin. The depths of Moho discontinuity in the southern ocean of Ulleung-island is 16--17 km, which is much lower than in the land. The result of crustal structure modeling in this study is similar to that computed by prior seismic exploration around this area.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.50-51
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• 1999

라돈($^{222}R$)은 암석이나 토양 같은 지각물질에서 발생되는 3.82일의 반감기를 가진 자연 방사선물질로 1980년대 중반부터 미국을 비롯한 유럽의 선진국에서 환경적인 측면에서 라돈의 관심이 증대되었다. 한편, 국내에서의 라돈에 관한 연구는 실내공기질 분야에서 진행되고 있으나 대기환경적 측면에서의 종합적이고 체계적인 연구가 활발히 이루어지지 않고 있는 실정이다.(중략)

• Knowledge Management Research
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• v.24 no.1
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• pp.223-243
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• 2023

RPA is implemented through management policy and enforced in mandatory environments to enhance performance and efficiency in various fields. However, the success of RPA implementation depends on the level of active engagement from organization members, even in a mandatory setting. This study identifies perceived ease of use, usefulness, accountability, perceived risk, and self-efficacy as variables that influence conative use behavior, which consists of reflective secondary factors such as immersion, reinvention, and learning. Data was collected from 207 office workers in various industries who have experience with RPA to test the proposed research model. The structural equation was verified using SPSS 20.0 and SmartPLS 4.0, and the analysis showed that all the proposed variables had a significant impact on conative use behavior. Our research findings provide theoretical and practical implications in knowledge management, enabling companies that implement RPA to recognize and address factors that encourage their members to actively use RPA.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.4
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• pp.254-264
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• 2018

The study aims were to verify the influences of job environment factors and work attitude on turnover intention of school foodservice employees, and then to verify the mediating effect of organization commitment between six areas of worklife and turnover intention so that organizations can intervene to reduce the turnover intentions of employees. The subjects were 205 employees who were working in the school foodservice field. The job environment factors were measured by six areas of worklife (workload, control, reward, fairness, community, value) and the organizational commitment was measured by two types of commitments (affective, continuance). The results were as follows. First, workload, reward, community and value of six areas of worklife reduced affective commitment, control and fairness increased continuance commitment, and affective commitment reduced turnover intention. Second, only reward and community showed direct effect on turnover intention, but all six areas of worklife had a statistically significant indirect effect on turnover intention through affective commitment. These results showed that job environment factors had both direct and indirect effect on employees' behavior through employees' affection. These findings imply that organizations can control employees' turnover intention by providing education or social support to maintain their affective commitment even when organizations cannot change job environment.

• The Journal of Engineering Geology
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• v.31 no.4
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• pp.659-669
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• 2021

The purpose of this study is to elucidate the relationship between occurrence of natural radioactive materials such as ²³⁸U and ²²²Rn and original mixing ratio of helium isotope of groundwater from various geology, and to suggest the underground aquifer environment from helium original mixing data. 9 groundwater samples were collected from five study areas, and ²³⁸U, Rn-222 and helium isotope were analyzed. A high ²³⁸U content of the range of 218~477 ㎍ /L in the groundwater occurs in the twomica granite. ⁴He air-crust mixing ratio and the Rn-222 content show a rough relation, that is, Rn-222 content increases according to the increase of ⁴He crust mixing ratio. Because of helium and radon are an inert gas, their behavior in underground environment is assumed as an analogous. The ²³⁸U content and He isotope in groundwater does not show any distinct correlation. The groundwater can be classified as three groups (air, air-crust mixing, crust-mantle mixing origin) on the diagram of ³He/⁴He vs ⁴He/²⁰Ne, which is composed of original mixing line from air-crust-mantle end members. This original mixing of helium can provide the information of underground aquifer characteristic such as the connection with surface environment or isolation condition from air environment.

• Economic and Environmental Geology
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• v.24 no.4
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• pp.447-463
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• 1991

Petrological and chemical studies of Precambrian dikes in the southern Lake Superior region were conducted with the objects of evaluating magma source and constraining models for the paleo-tectonic environment. Forty-six samples were analyzed for major, trace, and rare earth elements. Chemical data of the studied dikes are typical of continental tholeiites and showing iron-enrichment fractionation trend. With wallrock contamination carefully evaluated, a series of tectonic discriminating methods utilizing immobile trace elements indicate that the source magma was a high-Ti tholeiitic basalt similar to present-day T-type MORB. Effect of chemical contamination from wallrock assimilation accmulates with increasing differentiation. Evolved rocks show LREE enriched patterns and have enhanced levels of LIL elements (e.g., Rb, K, Ba, Th), but low levels of high field strength elements (e.g., Nb, P, Ti) with respect to their neighboring elements. It is suggested from this study that this enrichment possibly due to a combination of a feature inherited from the subcontinental lithosphere and crustal contamination. Geochemical signatures of these rocks are distinctively different from those of arc-related volcanics. Comparisons with chemistries of modern magmas show a pattern of overlap between Within-plate and ocean-floor characteristics, and chemical signatures of these rocks favor a model of intrusion into a crustal environment undergoing lithospheric attenuation.

• Journal of the Korean earth science society
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• v.24 no.3
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• pp.128-134
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• 2003

This study is focused on how much middle school students who study the chapter of first-grade science,'The Material and Change of the Earth's Crust', connect and understand what they learn with their environment and surroundings. This paper will discuss the connection between school education and living surroundings and how much the difference between the surroundings influences students' concepts and attitudes toward science. This study included 330students in the second year of middle schools from Jeonju, Buan and Jinan in Jeollabuk-do. This study analyzed students' concepts of mineral and rocks by having them observe samples in class. Only 16 percent of the students observe surrounding rocks with interest, but most of them are not interested. Chaesukgang and Mountain Mai are two local places in Jeollabuk-do which have a lot of specific stratum and geological structures, so it's easy for teachers to provide an outdoor experience by showing the students rocks and geological structures. Although which students have a little more observation experience than Jeonju area students, students who throughout the county seldom do outdoor observation learning. By collecting and observing the surrounding minerals and rocks, along with teaching the chapter 'The Materials and Change of the Earth's Crust', and by visiting outdoor locations while teaching about geological structures, we can improve our teaching.

• Knowledge Management Research
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• v.23 no.1
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• pp.47-67
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• 2022

Computer and Internet information technologies(ICTs) have changed the modern service industry and people's life style. In particular, the global spread of COVID-19 has attracted more attention to contact service types such as self-service technology. With the increase in labor costs and the enhancement of consumer self-awareness, more and more companies transfer part of their work to customers through their own service technology. This study seeks to answer the following questions. (1) Do technology difficulty and safety perception affect customer value recognition in the self-service technologies? (2) Does customer value recognition influence the intention to use such technologies continuously? This study conducted an empirical analysis with 327 samples to validate the influence of self-service characteristics(technology difficulty and safety perception) on customer value recognition and continuous utilization intentions. Also, it analyzes the moderating effects of age and frequency of use on the relationship between self-service characteristics and customer value recognition. The study results show that the technology difficulty does not affect the customer's perceived value recognition; and the higher the customer's value recognition, the higher the intention of continuous use.

• Information Systems Review
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• v.20 no.1
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• pp.41-59
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• 2018

This study analyzed the factors that affect acceptance of online direct marketing in agricultural companies. Empirical analysis was conducted using the research model based on the individual's technology acceptance model (TAM) and the information technology adoption models in organizations. These models have four dimensions: 1) technology characteristics, which include perceived usefulness and perceived ease of use of TAM 2) CEO characteristics, which including the innovativeness and IT capability of CEOs; 3) organizational readiness, which include financial, technological, and human resources capabilities and 4) environment and external pressure, which include government support and changes to the Internet environment. These concepts were empirically tested. A total of 209 valid data were collected through questionnaires and analyzed using confirmatory factor analysis and path analysis through the application of structural equation modeling. Results show that perceived usefulness, IT capability of CEOs, and changes to the Internet environment have significant effects on the adoption intention of online direct marketing. However, perceived ease of use, CEO innovativeness, government support, and the variables of organizational readiness dimension did not have significant effects on adoption intention. This study suggests practical implications for adoption of online direct marketing in agricultural companies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.2
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• pp.354-361
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• 2007

The purpose of this paper is to provide design information about children facilities, in which children's demands as main users are subject to be missed because of the shortage of children's communication ability in making design decisions. For this purpose various studies on childhood environment-behavior characteristics supporting children's demands are examined. The main part of this paper is divided into two categories, personal characteristics and social characteristics, and each category has several sub-categories. In personal characteristics, issues related to environmental perception and cognition are examined focused on development and change in childhood. Subjects about social characteristics include privacy, personal space, territoriality and density. Each part deals with definition and function of each items, and issues related to environmental design of children's facilities.