• Korean Journal of Remote Sensing
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• v.34 no.2_2
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• pp.393-406
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• 2018

Every year in the ocean, various accidents occur frequently and illegal fishing is rampant. Moreover, their size and frequency are also increasing. In order to reduce losses of life or property caused by these, it is necessary to have a means to perform remote monitoring quickly. As an effective platform of such monitoring means, an Unmanned Aerial Vehicle (UAV) is receiving the spotlight. In these situations where marine accidents or illegal fishing occur, main targets of monitoring are ships. In this study, we propose a UAV based ship monitoring system and suggest a method of determining ship positions using UAV multi-sensory data. In the proposed method, firstly, the position and attitude of individual images are determined by using the pre-performed system calibration results and GPS/INS data obtained at the time when images were acquired. In addition, after the ship being detected automatically or semi-automatically from the individual images, the absolute coordinates of the detected ships are determined. The proposed method was applied to actual data measured at 200 m, 350 m, and 500 m altitude, the ship position can be determined with accuracy of 4.068 m, 8.916 m, and 13.734 m, respectively. According to the minimum standard of a hydrographical survey, the ship positioning results of 200 m and 350 m data satisfy grade S and the results of 500 m data do grade 1a, where the accuracy is required for positioning the coastline and topography less significant to navigation order. Therefore, it is expected that the proposed method can be effectively used for various purposes of marine monitoring or surveying.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.329-338
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• 2019

In this study, we analyze consumer preferences based on the agricultural box scheme attributes, and make a suggestion for business revival. We estimate the marginal willingness to pay (MWTP) for box scheme attributes using a choice experiment. Attributes include the bundle method, the delivery method, and price. To select an efficient model for statistical analysis, we evaluate the conditional logit model, heteroscedastic extreme value model(HEV model), multinomial probit model, and mixed logit model under different assumptions. The results of these four models show that the bundle method, the delivery method, and price are statistically significant in explaining the probability of participation in a box scheme. The results of likelihood ratio tests show that the heteroscedastic extreme value model is the most appropriate for our survey data. The results also indicate that MWTP for a change from fixed type to selection type is KRW 7,096.6. MWTP for a change from parcel service to direct delivery and cold-chain delivery are KRW 3,497.5 and KRW 7,532.7, respectively. The results of this study may contribute to the government's local food policies.

• The Journal of Society for e-Business Studies
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• v.19 no.4
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• pp.231-249
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• 2014

We define $21^{st}$ century as an amalgamation of globalization and localization, or Glocalization. Additionally, due to the increasing supply of smart phones and wide usage of social networking services, the ability to utilize such global and regional information has increased a coperation's competitiveness in its market, and even the business models have evolved from the conventional "production and distribution" to E-commerce, through which either a direct or a non-direct transaction is possible. My hypothesis is that the ability to adapt to this trend is possible through transfer of learning, and consequently, this will have an impact on company's performance. Thus, this thesis analyzes the mid- to the long-term impact of such ability and environmental factors on the performance and technology innovation of Korean companies in China. Ultimately, this study intends to engender a basic foundation for a corporation's management strategy in China. Finally this research focuses on those Korean companies in China only and on the proof of influential factors' impact on technological innovation and technological innovation's impact on those corporations' future performances. Section I is an abstract and section II, the case examines the uniqueness and current status of Korean companies in China identifies the concept and the definition of influential factors such as education-orientation, technological innovation, and performance, and then scrutinizes each factors through a closer look at their past researches. Section III explains the thesis model, the survey's method and target, the thesis, variable factors, the content, and the method of analysis. In section IV, the thesis is proved based on the outcome of the survey. The result in Section V highlights the high comprehension of technological innovation: both education-orientation and technological innovation prove to have a positive (+) correlation with the performance. The vision on education orientation proves to have a positive (+) influence on technological innovation. The vision on education-orientation and technological innovation prove to have a positive (+) influence individually on company's performance.

• Korean Journal of Social Welfare
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• v.61 no.2
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• pp.325-348
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• 2009

This study intends to investigate the main and mediating effects which caregiving appraisal and positive reappraisal exert on quality of life (QOL) of primary family caregivers of cancer patient considering the relationship with social support. The processes of this study areas follows. First, the variables which research model were chosen on the basis of stress-appraisal-coping theory through reviews of the previous studies. Second, a survey was conducted upon 295 primary caregiver of patient with cancer at National Cancer Center. Collected data were analyzed by SPSS 12.0 and SEM (Structural Equation Modeling) method using AMOS 5.0. The summary of the result is as follows. First, the entire model including measurement and structural model shows sufficient fit index of CFI(.951), TLI(.940) and RMSEA(.062). Second, the results of analysis of direct effects among variables are as follows. The 'Social support' has statistically significant direct effect on the 'feeling of burden' and 'growth'. The 'feeling of burden' has statistically significant direct effect on the 'growth' and 'QOL-mental and physical'. The 'growth' has statistically significant direct effect on the 'QOL-mental'. Third, the results of analysis of mediating effects of the 'social support and QOL' and 'feeling of burden and QOL' are as follows. The effects of 'social support' on 'QOL-mental' are significantly mediated by the 'feeling of burden' and 'growth'. The effects of 'social support' on 'QOL-physical' are significantly mediated by the 'feeling of burden'. The effects of 'feeling of burden' on 'QOL-mental' are significantly mediated by 'growth'. Through this research, these implications in social work study and practice are found: (1) this study extended the scope of study in the caregiver's health area from negative sides into positive ones by using growth variables as positive reappraisalof caregiving in research model, which has not been tried on the Korean family caregivers of the cancer patient. (2) The effects of positive reappraisal on QOL-mental can provide a foundational necessity for social workers to help family caregivers find positive meaning in their caregiving experience. This approach of social work practice will improve QOL of family caregivers. (3) This study present a framework including social support, negative appraisal, positive reappraisal, and QOL variables available to social work practice and explaining affective relationships among these variables in various aspects.

• Journal of Venture Innovation
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• v.1 no.1
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• pp.145-164
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• 2018

The purposes of this study was to investigate job related attitudes of emotional labors working at call centers in Korea. The attitudinal variables were burnout, psychological capital and turnover intention with job characteristics as the independent variables. In addition, leadership behaviors of the superiors, self leadership behavior in particular, was incorporated to see if it has any bearing on these relationship as moderating variable. Data has been collected from 543 respondents for this study using questionnaire method. The survey for the actual analysis of the research was done and analyzed with the employees who work for contact centers in Seoul, Busan, and Gwangju, Korea. The survey was done for 24 days from November, 2016 through December, 2016. * The following study results were revealed: First, the job characteristics does not have direct positive effect on turnover intentions. Second, the job characteristics were related positively to job burnout. Third, the job burnout does mediate the relationship between job characteristics and turnover intentions. Lastly, results of research on the moderating effect of self leadership in relationships between emotional labor, job burnout, psychological capital and turnover intention show that super leadership has only a limited regulatory effect between job characteristics and turnover intention.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.3
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• pp.159-165
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• 2005

The characterization of radiological contamination inside pipes generated during the decommission of a nuclear facility is necessary before pipes can be recycled or disposed. But, existing direct measurements of radioactive contamination level using the survey-meter can not estimate the characteristic of contamination on a local area such as the pipe inside. Moreover, the measurement of surface contamination level using the indirect methods has many problems of an application because of the difficulty of collecting sample and contamination possibility of a worker when collecting sample. In this work, plastic scintillator was simulated by using Monte Carlo simulation method for detection of beta radiation emitted from internal surfaces of small diameter pipe. Simulation results predicted the optimum thickness and geometry of plastic scintillator at which energy absorption for beta radiation was maximized. In addition, the problem of scintillator processing and transferring the detector into the pipe inside was considered when fabricating the plastic detector on the basis of simulation results. The characteristic of detector fabricated was also estimated. As a result, it was confirmed that detector capability was suitable for the measurement of contamination level. Also, the development of a detector for estimating the radiological characteristic of contamination on a local area such as the pipe inside was proven to be feasible.

• Geophysics and Geophysical Exploration
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• v.6 no.2
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• pp.57-63
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• 2003

For the dectection of small cavity in the hard rock, we investigated the feasibility of crosswell travel-time tomography and Kirchhoff migration technique. In travel-time tomography, first arrival anomaly caused by small cavity was investigated by numerical modeling based on the knowledge of actual field information. First arrival delay was very small (<0.125 msec) and detectable receiver offset range was limited to 4m with respect to $1\%$ normalized first arrival anomaly. As a consequence, it was turned out that carefully designed survey array with both sufficient narrow spatial spacing and temporal (<0.03125 msec) sampling were required for small cavity detection. Also, crosswell Kirchhoff migration technique was investigated with both numerical and real data. Stack section obtained by numerical data shows the good cavity image. In crosswell seismic data, various unwanted seismic events such as direct wave and various mode converted waves were alto recorded. To remove these noises und to enhance the diffraction signal, combination of median and bandpass filtering was applied and prestack and stacked migration images were created. From this, we viewed the crosswell migration technique as one of the adoptable method for small cavity detection.

• Survey Research
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• v.12 no.1
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• pp.153-174
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• 2011

This research aims to discuss the causes of inaccuracy in public opinion polls currently conducted in Korea. In particular, identifying the problems in sampling frame and sampling methods in political and social public opinion polls is an important question. Currently, most polling organizations operating in Korea are using phone number directories provided by Korea Telecom(KT) as its sampling frame for conducting most political polls. A critical problem of using a phone number directory as a sampling frame is that unlisted phone numbers can never be included in the sample. If a systematic difference in socio-demographic or politico-economic characteristics exists between the listed number using group and the unlisted group, using a phone number directory as a sampling frame cannot produce a sample that can represent the whole adult population in Korea. According to the poll result commissioned by the Asan Institute for Policy Studies in January 2011, there are statistically significant differences in socio-demographic and politico-economic characteristics between those two groups, and those differences led to the differences in the presidential job approval rating and party support. Our findings include that the listed number using group is more pro-Grand National Party and show stronger support for the president than the unlisted group.

• Journal of Environmental Health Sciences
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• v.41 no.4
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• pp.231-240
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• 2015

Objectives: Blood mercury levels among adults living in certain areas of the Gyeongsang Provinces have been shown to be very high (Kunwee County $29.6{\mu}g/L$, Yeongcheon-city $26.7{\mu}g/L$). The purpose of this project was to determine mercury exposure levels in schoolchildren and factors related with their mercury levels in high mercury exposure areas identifyed by the 2007 Korea National Environmental Health Survey. Methods: From June to September 2010, 1,097 students from grades 3 to 6 at 19 elementary schools participated in this study, including 294 students from 10 elementary schools in Kunwee County, 529 students from Yeongcheon City, 122 students from two elementary schools in Pohang City, North Gyeongsang Province, and 152 students from two elementary schools in Ulsan Metropolitan City. Biological samples from schoolchildren, including whole blood, urine and hair, were collected to measure total mercury at the time of a health check up. Information about children was collected by questionnaire. Total mercury concentrations in blood were measured using the Direct Mercury Analyzer 80 with the gold-amalgam collection method. Results: The mean mercury levels were $2.70{\mu}g/L$ in 1,091 blood samples, $2.25{\mu}g/g-creat.$ in 820 urine samples and $1.03{\mu}g/g$ in 1,064 hair samples. Blood mercury levels in the schoolchildren was slightly higher than the result of $2.4{\mu}g/L$ from a 2006 survey of elementary school children on exposure and health effects of mercury by the National Institute of Environmental Research. However, 0.3% and 4.5% of participants exceeded the reference level of blood mercury by CHBMII ($15{\mu}g/L$) and the US EPA ($5.8{\mu}g/L$), respectively. The reference level of urine by CHBMII ($20{\mu}g/L$) was exceeded by 0.4% of participants. As factors, residence period in the study areas, residence type, father's education level and income all showed significant associations with mercury level in the biological samples. The number of dental amalgam sides showed an association with urine mercury. Fish intake preference and fish intake frequency were important factors in mercury levels. In particular, intake of shark meat and recent intake of shark meat were associated with higher mercury levels. In this regard, participation in the performance of an ancestral rite showed a relation with higher mercury levels. Conclusion: The intake of shark meat was very important factor to high mercury exposure level. It is recommended to monitor and manage students with high mercury exposures who exceeded CHBM II and EPA guidelines, and include blood mercury testing in the Children's Health check up for this province.

• The Journal of the Korea Contents Association
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• v.21 no.9
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• pp.431-445
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• 2021

The purpose of this study was to provide implications for social work practice by examining the influence of career barrier on smart-phone addiction through self-esteem and depression among out-of-school adolescents. Using data from the Panel Survey of School Dropouts conducted by the National Youth Policy Institute, this study examined the research questions by analyzing the direct and indirect influences of career barrier on smart-phone addiction with the PROCESS macro method. First, the results of this study showed that out-of-school adolescents' career barrier statistically significantly increased smart-phone addiction. Also, out-of-school adolescents' depression mediated the influence of career barrier on smart-phone addiction, but out-of-school adolescents' self-esteem did not mediate the influence. However, out-of-school adolescents' self-esteem and depression dual-mediated the influence of career barrier on smart-phone addiction. The level of career barrier decreased the level of self-esteem, and in turn increased the level of depression, and finally increased the level of smart-phone addiction. Based on the findings, practical strategies to address the smart-phone addiction of out-of-school adolescents were discussed.