• The Transactions of the Korean Institute of Electrical Engineers B
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• v.55 no.10
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• pp.521-527
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• 2006

After various measuring methods and system were investigated, Rogowski colis for the measurement of parameters in current zero region were designed and manufactured. Using the Rogowski coils and a 38kV 40kA VCB (vacuum circuit breaker), at last the post-arc current has been successfully measured firstly. It was found that the Rogowski coils used in this study have good characteristics and propriety to measure the parameters of current zero. We realized that the data processing for evaluating the post-arc current from the experimental results needs much more careful attention than that for building the measuring technique and system. The magnitude of post-arc current and the falling time of it to zero are proportioned to the rate of current di/dt. The magnitude of post-arc currents were around $1{\sim}3A$ to the interruption current of $20{\sim}30kA$ in the model VCB.

• The Transactions of the Korean Institute of Power Electronics
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• v.14 no.1
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• pp.46-53
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• 2009

A new zero-current switching LLC resonant post-regulator for multi-output power system is proposed in this paper. A conventional LLC resonant converter employs extra non-isolated DC/DC converters to obtain tight-regulated multi-slave output voltages. Therefore, it has several serious problems such as a poor efficiency and high cost of production. The proposed post-regulator features low voltage and current stress across the output rectifier diodes and power switches. Moreover, the proposed post-regulator requires only one power switch instead of the bulky and expensive non-isolated DC/DC converter. Therefore, it features a simple structure and lower cost. Especially, since the proposed post-regulator can ensure the ZCS of all power switches, it has very desirable advantages such as more improved EMI characteristics and reduced switching losses. Finally, to confirm the operation, validity, and features of the proposed circuit, experimental results from a proposed zero-current LLC resonant post-regulator are presented.

• Proceedings of the KIEE Conference
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• 1999.07a
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• pp.369-371
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• 1999

The post-arc current in VCB(Vacuum Circuit Breaker) was calculated from the transient recovery voltage. A differential equation for the post-arc current was derived from the equivalent circuit of the test circuit. And it's results were showed.

• Journal of Power Electronics
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• v.16 no.6
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• pp.2258-2271
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• 2016

In this paper, some crucial performance characteristics related to the operational reliability of the post-fault Pulse Width Modulated (PWM) rectifiers, such as line current harmonic distortion, Common Mode Voltage (CMV), and current stress on the capacitors, are fully investigated. The aforementioned performance characteristics of post-fault rectifiers are highly dependent on the utilized space vector modulation (SVM) schemes, which are also examined. Detailed analyses of the three most commonly used SVM schemes for post-fault PWM rectifiers are provided, revealing the major differences in terms of the zero vector synthesis approaches. To compare the performances of the three SVM schemes, the operating principles of a post-fault rectifier are presented with various SVM schemes. Using analytical and numerical methods in the time domain, the performances of the line current distortion, common mode voltage and capacitor current are evaluated and compared for each SVM scheme. The proposed analysis demonstrates that the zero vector synthesis approaches of the considered methods have significant impacts on the performance characteristics of rectifiers. In addition, the advantages and disadvantages of the proposed SVM schemes are discussed. The experimental results verify the effectiveness and validity of the proposed analysis.

• Korean Journal of Adult Nursing
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• v.12 no.1
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• pp.147-162
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• 2000

Predicting factors of post-stroke depression were investigated. The subjects were 254 stroke patients who had been discharged and visited regularly the outpatient clinic for follow up care. The influencing factors were classified into five categories : demographic, disease-related, current state, social support, and illness intrusiveness. Sex, age, job, and educational level were defined as the demographic factor. The disease-related factors included stroke type, illness duration, attack frequency, and NIH score. ADL, cognitive function, and social activity were considered as the current state factors. The social support was measured as the perceived amount of social support. Illness intrusiveness means the perceived illness induced life style disruptions. Demographic, disease-related, current state, and social support were hypothesized to directly and indirectly affect post-stroke depression through illness intrusiveness. The illness intrusiveness was hypothesized to directly affect post-stroke depression. The hierarchial multiple regression was used to identify significant factors. The result showed that this model explained 43.3% of variance of post-stroke depression. And the prevalence of post-stroke depression was 38.8%. Among the demographic factors, job was identified as a main contributor to indirectly increase the post-stroke depression. Among the disease-related factors, stroke type, attack frequency, and NIH score were found to indirectly affect the post-stroke depression. Among the current state factors, ADL and social activity indirectly affected the post-stroke depression through illness intrusiveness. Social support and illness intrusiveness were identified to directly affect the post-stroke depression. This study has proved the factors likely to be implicated in the development of post-stroke depression. Based upon these results, it is recommended that the nurses who take care of post-stroke patients consider the risk factors such as social support, illness intrusiveness et al. Also programs which decrease the illness intrusiveness and increase the social support to reduce post-stoke depression recommended to be developed.

• Journal of Korean Academy of Nursing Administration
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• v.9 no.1
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• pp.141-150
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• 2003

Purposes : This study was to investigate the job stress and turnover intention related to transfer of duty post of staff nurses working in general hospitals. Method : The subjects of this study were 384 staff nurses working in 6 general hospitals, with more than 200 beds, in Daegu and Kungbuk province in Korea. Data were collected through questionnaires and from Sep. 15 to Oct. 6, 2001. The used tool for measuring the degree of job stress was developed by Kim and Gu(1984) and the used tool for measuring the degree of turnover intention was developed Kim and Lee(2001). The data were analyzed into frequency, percentage, mean, standard deviation, t-test, ANOVA, Tukey's post hoc contrast, Pearson's correlation coefficient according to the purpose of study by use SPSS Win 10.0 statistical program. Results : The following are the results of the study: (1) Average score of the job stress, turnover intention of resignation of the subjects were 2.64 and 4.44. (2) The result of the analysis of job stress related to transfer of duty post was higher in job stress; not satisfaction of current duty post(t=-2.06, p=0.04). (3) The result of the analysis of turnover intention related to transfer of duty post was higher in turnover intention; period of the an advance notice when transfer to current duty post less than 7day(F=3.55, p=0.02), not satisfaction of current duty post(t=-2.45, p=0.02), want the transfer from current duty post(t=3.68, p=0.00). (4) The study reveals that there was statistically significant positive correlation relationship between job stress factors and turnover intention(r=.183, p=.000). Conclusion : The study which relating to period of the an advance when transfer and satisfaction of current duty post and reconsideration of transfer of duty post shows statistically significant difference between job stress and turnover intention. Therefore it is regarded that is needed to set a period of profer advance notice, grip on unsatisfactory factor of current duty post and intervention and management of the subjects were wanted transfer of duty post.

• Journal of the Korean Vacuum Society
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• v.8 no.3A
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• pp.238-244
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• 1999

Pt/SBT/Pt capacitors were fabricated using the MOD-derived $SrBi_{2x}Ta_2O_9$ (SBT) films and their ferroelectic and leakage current characteristics were investigated with post annealing at 400~$800^{\circ}C$. Although the MOD-derived SBT film exhibited the hysteresis loop typical for the leaky film, the well-saturated ferroelectric hysteresis loop could be obtained by post annealing the Pt/SBT/Pt capacitors at $550^{\circ}C$~$800^{\circ}C$. The remanent polarization $2P_r$ of the SBT film exhibited a maximum value of 9.72$\mu\textrm{cm}^2$ with post annealing at $600^{\circ}C$, and then decreased with increasing the post annealing temperature above $600^{\circ}C$. The MOD-derived SBT films exhibited the high leakage current density of ~$10^{-3} \textrm{A/cm}^2$ at 75kV/cm. With post annealing the Pt/SBT/Pt capacitor at 600~$800^{\circ}C$, however, the leakage current density decreased remarkably to less than $10^{-6}\textrm{A/cm}^2$ at 75kV/cm.

• Proceedings of the KWS Conference
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• 2008.05a
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• pp.50-50
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• 2008

• Journal of East-West Nursing Research
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• v.11 no.1
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• pp.12-24
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• 2005

The objective of this research is to explore the attitude on the transfer of duty post and job satisfaction of nurses. The subjects of this study were 512 nurses who have engages in the K-university hospital. The measurement tool consisted of attitude on the transfer of duty post, job satisfaction. The collected data have been processed using SPSS/PC 12.0 program: The results of this study were as follows: 1. The age the subjects was from 21 to 56 and average 32, blow 3 years experience in current duty post occupied most by 37.1%. The experience of the transfer of duty post showed 50.2%. 51.4% of the nurses wanted $3{\sim}5$ years as the suitable periods for the transfer of duty post showing the highest degree of frequency. 2. The positive degree of the attitude on the transfer of duty post of the nurses appeared average (3.36) to maximum evaluation point 5, and when asked about 4 factors the nurses wanted individual development most by (3.72) while administration management was lowest by (2.65). The satisfaction degree on their job appeared to be average (3.06) to the maximum point 5, and when asked about 7 factors, interaction appeared to be the highest by (3.63), here we saw that interaction was the most important elevating factor of the job satisfaction degree. 3. In the relation of the attitude on the transfer of duty post according to general characteristics, there were the significant difference according to whether it is necessary for the current duty post and periodical duty post to be transferred. In the relation between general characteristics and job satisfaction degree there were the significant differences according to age, marital status, education, position of nurse, hospital clinical nursing experiences, satisfaction degree with current post and the hope of the transfer of duty post from current post. 4. The correlation between attitude on the transfer of duty post and job satisfaction degree was positive relation(r=0.137, p=.002), that the higher the degree of positive attitude on the transfer of duty post the higher the degree of job satisfaction.

• Journal of the Korean Society of Costume
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• v.46
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• pp.49-66
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• 1999

The bisexuality deconstructivity and diversity that are great characteristics on the comtemporary fashion are showed in the fashion collections. The purpose of this paper is to investigate and analyze the influence of these characteristics made by the post modern-feminism fashion through the cultural pattern analysis. The post modern-feminism was analyzed by dividing the cultural pattern into 1) the deconstructivity of androcentrism -This characteristic was presented in the costume design that breaks the basic from of the line color and quality of the material showing in men's clothes. 2) By rejecting main current fashion -Subculture style appeared in main current fashion the boundary of main and anti-main current fashion was vagued and the phenomena that the identity of subgroup was weakened were showed. 3) In the coexistence of double-sided value -This characteristic was presented in the cross-dressing fashion that cut away women's slender part and men's rough part. 4) In the open-minded thought of gender -This tendency was reached an extreme from excessive exposure to design which gives the sexual stimulus. This paper is expected to be helpful to understand the contemporary fashion by treating the cultural category associated with post-modern feminism in relation to contemporary fashion and to establish the direction of 21 century fashion.