• The Transactions of the Korean Institute of Power Electronics
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• v.8 no.6
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• pp.504-511
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• 2003

In this paper, inverter type neon power supply using a piezoelectric transformer is fabricated and its characteristic is investigated. Developed neon power supply is composed of basic circuit and blocks, such as rectifier part, frequency oscillation part and piezoelectric transformer and resonant half bridge inverters. In this paper for complement the low power limitation, piezoelectric transformer at parallel connected driving by inverter is studied for noon tubes system of high power. When piezoelectric transformer is connected with parallel, LC filter connection method with parallel and selection of inductance L and capacitor C of primary side is suggested for reduce unbalanced current at the terminal of each transformer. Piezoelectric transformers use piezoelectric ceramic devices. Thus it is wireless therefore it has high power density, high Isolation level, low loss, more light, and miniaturization. In addition, high voltage transfer ratio is expected because there is no leakage inductance. Also, it has economic merit that the electrical loss Is low because structure is simple, small and tighter weight.

• Economic and Environmental Geology
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• v.52 no.5
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• pp.357-366
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• 2019

Deposition of the Daedong Supergroup has been considered to be related with the Triassic Songrim and Jurassic Daebo orogenies. The Chungnam Basin fills is an important sedimentary succession to understand the geological evolution of the Early to Middle Mesozoic Korean Peninsula. Previous paleontological and paleomagnetic studies have suggested the Late Triassic to Early Jurassic sedimentation of the Chungnam Basin fills. However, the orogenic model of the basin development has remained controversial because recently reported zircon U-Pb isotopic ages are not harmonious with the previous studies. This paper aims to review the stratigraphy, depositional age, and composition of the Chungnam Basin fills, together with test of the basin development models.

• Journal of the Economic Geographical Society of Korea
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• v.19 no.2
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• pp.286-299
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• 2016

The increase of elderly population is inevitable a universal trend in developed countries. The Korea also followed this tendency. Especially the elderly population in Korea has been rapidly increasing since the 1990s. The rural population is aging more rapidly than the urban one because younger generations move into the urban area, due to better jobs and children education's opportunities. However, the majority of studies on population ageing are focused on the urban area rather than the rural ones. Rural areas also have been excluded as a priority of the national welfare policy for the elderly people. This paper tries to analyze the population ageing among regions and to identify the regional disparity between the elderly people and the level of public services in the rural area. Based upon these results, this study notes some policy alternatives for the improvement of quality of life of the rural elderly. It also suggests on the suitable location of public service facilities in the rural areas.

• Journal of vocational education research
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• v.30 no.4
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• pp.1-22
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• 2011

Paradoxically, leadership has not only positive effects but also negative effects. The purpose of this study is to examine supervisors' dysfunctional leadership behaviors, antecedents and results in order to draw HRD implications for protecting organizations and employees from dysfunctional leaders and provide implications for leadership development. A qualitative research method based on semi-organized interviews with 28 employees from S-group was used. The results of this study show that the dysfunctional leadership behaviors were associated with ten behavioral categories: belittling and insulting the subordinates, authoritative and arbitrary behaviors, self-aggrandizement, biased preference for certain personnel, arrogance, micro-managing, inability to change and adapt, discordance between words and actions, over-dependance on supervisor, lack of ethics and values. Dysfunctional leadership behaviors were casually attributed to 'personal traits & experience', 'task characteristics', and 'internal & external environments of the organization'. Finally, the results of supervisor's dysfunctional leadership behaviors on employees and the organizational effects were 'increased turnover rate', 'declining work efficiency', 'collapsing morale', 'retraining innovative thinking', 'passive working culture', 'discouraging organizational vitality', 'discouraging organizational synergy', 'losing loyalty' and 'declining trust on supervisor'.

• Korean Journal of Culture and Social Issue
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• v.17 no.1
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• pp.19-49
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• 2011

In this study, multilateral conceptualizations of underemployment were measured in terms of wages, social status, skill utilization and permanence of the job, and then the effects of antecedents on underemployment and the effects of underemployment on organizational adaptation were examined. Data obtained by a longitudinally designed survey at intervals of 18 months with the reemployed(N = 153) after job loss were used. The underemployment measures include 1) the ratio of wage change 2) the ratio of status change 3) the ratio of education 4) the occurrence of change from the permanent job to temporary job, 5) overqualification - growth opportunity, 6) overqualification - mismatch. The first four measures are social-economic and objective measures and the last two measures are psychological and self-reported ones. Demographic variables(sex, age, education level, and period of unemployed), circumstantial variables(economic hardship, number of dependents), and psychological variables(job-seeking self-efficacy, depression/anxiety, latent function) are included in antecedents. In the effects of antecedents on underemployment, age increases the level of underemployment in the aspects of wage and job status. Economic hardship increases the possibility of underemployment in the aspects of education and number of dependents increases the possibility of underemployment in the aspects of job status. Job seeking self-efficacy decreases the possibility of underemployment in the overqualification - no growth. Retention of latent function during the period of unemployment lowers the possibility of underemployment in the overqualification - no growth. The level of depression and anxiety during the period of unemployment raises the possibility of underemployment in terms of education and in the overqualification - mismatch. In the effects of underemployment on organizational adaptation, the higher the level of underemployment in the aspect of education is, the lower the level of person-organization fit, emotional commitment, and job satisfaction are. And the transition from permanent job to temporary job makes emotional commitment and job satisfaction lower. No growth and mismatch exerted a significant influence on organizational adaptation generally.

• Investigative Magnetic Resonance Imaging
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• v.17 no.3
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• pp.232-238
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• 2013

Purpose : We investigated the possible added value of magnetic resonance imaging (MR) in staging of malignant pleural mesothelioma (MPM) compared to computed tomography (CT). Materials and Methods: We retrospectively enrolled 20 patients (M;F = 14:6; mean age, 53.5 yrs) who diagnosed as MPM by histology and underwent CT and MR at initial evaluation from Jan 1997 to Dec 2012. Two radiologists performed clinical staging by using CT alone or MR alone in consensus. In patients underwent surgery (n = 13), we evaluated the diagnostic accuracy of CT and MR in terms of staging compared to surgical staging. In all patients, we compared clinical staging of CT only and CT with MR. Results: The diagnostic accuracy for T staging of CT only was 23.1% (3/13) and that of combined CT and MR was 38.5% (5/13), respectively. Among 13 patients underwent surgery, surgical stage was higher than combined CT and MR stage in 5 patients, but lower in 3 patients. CT only and combined CT and MR agreed in 85.0% (17/ 20). In cases of disagree (15.0%, 3/20), combined CT and MR showed higher stage than CT only. Conclusion: Combined CT and MR increases the diagnostic accuracy in staging of MPM compared to CT only and is important in determining the appropriate treatment in patients being considered for surgery.

• Journal of Korean Society for Geospatial Information Science
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• v.24 no.4
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• pp.83-88
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• 2016

The use of consistent coastlines is an important element for the systematic management of maritime boundaries and the interests of local governments. The Hydrographic and Oceanographic Agency conducted a preliminary survey for consistent coastline production, since 2001. As a result, the length of coastline was different by year. Because of the lack of systematic management, the use of incorrect data, etc. We also changed the coastline on the sea chart to show on a digital map for realization of terrain expression method. However, there was a variation in shoreline length due to various surveying techniques and shoreline extraction methods. In this paper, the characteristics of Jeju-do coastline were analysed by using a modified divider method of fractal dimension. The accuracy of the vectorization was determined by converting the actual distance in the Public Survey Amendment for proper divider use. With 1:5,000 and 1:25,000 digital maps of Jeju-si and Seogwipo-si each fractal dimensions were calculated. Jeju-si=1.14 and Seogwipo-si=1.12 in 1: 5,000. Jeju-si=1.13 and Seogwipo-si=1.10 in 1: 25,000. Calculated fractal dimension were correlated to data from digital maps. It was considered that complexity and scale of coastlines affected. In the future coastline length statistics and minimum ratio of calculated coastline length to original length need to be determined for consistency of coastline length statistics.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.1C
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• pp.129-139
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• 2004

This paper studies the support region of an optimum (minimum mean-squre error) fixed-rate scalar quantizer for a Weibull source. The support region is defined to be the interval determined by the outermost thresholds of a quantizer and plays an important role in its performance, and hence it motivates this study. The paper reports the following specific results. First, approximation formulas are derived for the outermost thresholds of optimum scalar quantizers for a Weibull distributions. Second, in the case of Rayleigh and exponential distributions the derived approximation formulas are compared for the evaluation of their accuracy with the true values of optimum quantizers. Numerical results show that the formula for the leftmost threshold stays within 1% of the true value for 128 and 256 quantization points or more, for Rayleigh and exponential distribution, respectively, while that for the rightmost threshold does so for 512 and 32 quantization points or more. These formulas exhibit increased accuracy with the number of quantization points. In conclusion, the formulas have high accuracy. The contribution of the paper consists in the derivation of closed accurate formulas for the support of optimum.

• The Korean Society of Law and Medicine
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• v.18 no.2
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• pp.3-46
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• 2017

Physician's Duty of Information is classified into three categories by legal function: 'Duty of Information to Report' to fulfill the patient's right to know; 'Duty of Information to Guide' patient's convalescing and staying healthy; 'Duty of Information to Contribute' to patient's self-determination. We classify the physician's duty of information because the legal effect from the breach of duty varies accordingly. The legal effect is focused on damage compensation responsibility for breach of duty. When a physician violates 'Duty of Information to Report', he subjects himself to liability of compensation for infringing on the patient's 'Right to Know'. When a physician violates 'Duty of Information to Guide', she subjects herself to liability for general medical malpractice. Finally, when a physician violates 'Duty of Information to Contribute', the physician is basically liable for violation of the patient's 'Right to Self- Determination' which refers to infringement on freedom of choice. However, in the case of situation that patient's refusal to the medical treatment would be presumed, the physician bears all liability for the patient's damage which includes both of property and mental damage.

• Korean Security Journal
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• no.46
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• pp.31-62
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• 2016

This study is about the phenomenological study of bodyguards' ethical dilemmas. Through this study, the meaning and essence of bodyguards' ethical dilemmas will be analyzed based on empirical facts. The purpose of this study is to provide basic information of the prevention and solutions for their ethical dilemmas and to understand and research the process and the essentials of them. To achieve this goal of the study, seven bodyguards who experienced ethical dilemmas working more than five years are selected as objects of the study. Colaizzi's six stage method are applied into this study so information gathered through interviews and questionnaire from 0ctober 1st, 2015 to November 20th, 2015 is analyzed. From the process of this research, these following conclusions are drawn considering validity of this study and ethical things. As a result, bodyguards' ethical dilemmas are divided into six centric meanings and 20 thematic statement. First, the centric meaning is conflict factors and the themes are discordance of pre-practice, regulatory or procedure problems, communication about sturcture and job and service disagreement. Second, the centric meaning is limited professional roles and the themes are institutional custom, decision making, priorities. Third, the centric meaning is difficulties of circumstantial judgement at work places and the themes are ambiguity of decision, conflict of knowledge, experience and opinion. Forth, the centric meaning is reasonable self-defense and the themes are lack of responsibility, rationalization, intentional negligence and sense of shame. Fifth, the centric meaning is difficulties of social network and the themes are the relationships between subordinates and superiors, the role of a moderator, uncooperative work and unpleasant sayings and doings. Sixth, the centric meaning is keeping secrets and the themes are burried for and illegal practice.