• 한국대기환경학회지
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• 제22권3호
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• pp.383-391
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• 2006

In Korea, the major source of serious air pollution is motor vehicles. Air pollution from vehicles has been annually increased. Then the government will try to control the vehicle emission by applying the effective emission management policy for the manufactured and in-used car. It is necessary to correctly calculate the emission factor for successful propulsion of the vehicle emission control policy. In this study, correlation analysis of exhaust emissions from vehicles between CVS-75 mode and Korea mode was conducted. A total of 25 light-duty buses were tested on the chassis dynamometer system in order to measure CO, HC, NOx PM and fuel efficiency (F.E.). For the test modes, 10 different Korea modes and CVS-75 mode were used. As the result of correlation analysis between those modes, most of the correlation coefficients were higher than 0.90. On the basis of high correlation between those modes, correction factors by driving conditions were estimated. Through the results of this study, we obtained essential basic data to correct difference from those modes.

• Journal of information and communication convergence engineering
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• 제9권1호
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• pp.32-37
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• 2011

In dispersion management (DM) and optical phase conjugation applied into optical transmission links with multi fiber spans for minimizing the impact of nonlinearity and group velocity (GVD), implementation possibility of DM using only one fiber span for pre- or postcompensation was assessed as a function of duty cycle of RZ pulse and residual dispersion per span (RDPS). It is confirmed that DM with optimal net residual dispersion (NRD) controlled by only one fiber span could be sufficiently applied into optical transmission links, though optimal NRD is more increased than that in transmission links with the general DM scheme of pre- and postcompensation. Thus, it is expected that optical transmission system is simply designed and implemented by applying the proposed DM scheme into real optical transmission links. Also, it is confirmed that the advantageous duty cycle of RZ is 0.5 and RDPS is setting to be small value for the effective transmitting wide signal wavelength range in optical links with optimal NRD controlled by only one fiber span.

• 동서간호학연구지
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• 제20권1호
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• pp.29-36
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• 2014

Purpose: The purpose of this study is to identify relationships among work environment, job satisfaction and turnover intention of emergency department (ED) nurses. Methods: The survey was given to 220 ED nurses which are located in G metropolitan from May 1st to July 31st of 2012. The results were analyzed by descriptive statistics, t-test, ANOVA, pearson correlation coefficients and stepwise multiple regression using SPSS WIN 19.0 program. Results: The turnover intension according to the general characteristics of the subjects has significant difference between emergency room experience, current duty satisfaction, and turnover plan in 1 year. In the correlation between work environment, job satisfaction and turnover intention of the subjects, work environment and job satisfaction have positive correlation, job satisfaction and turnover intention either job satisfaction and turnover intention have a negative correlation. Factors influencing turnover intention are job satisfaction, career and current duty satisfaction, also the full explanatory power of the model was 24.4%. Conclusion: The results indicate factors that influence turnover intention are job satisfaction, career, and current job satisfaction. We hope these result help to provide effective intervention strategies for reducing ED nurses' turnover.

• 동서간호학연구지
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• 제15권2호
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• pp.71-81
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• 2009

Purpose: This study was conducted to find out interrelation of health behavior and related variables to provide basic data for an effective health promotion for the taxi-divers. Methods: 293 male taxi-drivers from 2 cities in Korea participated in this study. The data were collected using questionnaires from April 17th to Jun 3rd, 2006, and analyzed by descriptive statistics, t-test, ANOVA, Pearson correlation, and multiple regression. Results: There were statistically significant differences according to monthly income, past illness or surgery, current disease or medication, frequency of fright on daily driving (FFDD), driving fatigue, working style, social support in health status; current disease or medication, FFDD, driving fatigue, duty shift, social support in health perception; body mass index (BMI), FFDD, driving fatigue, intention of changing job, social support in health behavior. Social support, health status, health perception, and health behavior were significantly correlated with one another. The multiple regression analysis showed that health perception (17.8%), BMI (6.8%), intention of changing job (5.7%), and driving fatigue (4.2%) explained the 34.5% variance of health behavior. And the 22.6% of variance of health perception was explained by social support (12.2%), health status (6.9%), and duty shift (3.2%). Conclusions: To promote the taxi-drivers' health, nursing intervention strategies unique for them should consider health behavior and affecting factors.

• 의료법학
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• 제16권1호
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• pp.155-190
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• 2015

법원은 2014년에도 의료와 관련된 의미 있는 판결들을 선고하였다. 법원은 수술 시 의료기구를 본래의 용도와 달리 사용하던 중 부러진 경우 이로 인한 사고에 의료진의 과실을 추정하였고, 설명의무와 관련하여 안전성이 검증되지 않은 수술을 시행하는 경우 설명의무 위반과 부작용 발생 사이의 인과관계를 인정하여 전손해배상이 인정될 수 있다는 점, 미용수술의 경우 일반적인 의료행위에 비하여 설명의무의 대상이 확대되어야 하는 점, 예상할 수 없는 범위에까지 설명의무를 인정할 수는 없는 점 등을 판시하였다. 또한 법원은 환자의 자기결정권과 의사의 진료의무 사이에 충돌이 발생한 경우 자기결정권 행사의 요건과 한계를 제시하였으며, 자동차보험계약이란 자동차사고와 관련된 배상 책임은 보험회사가 부담하기로 하는 계약이므로 비록 의료법에 위반되어 설립된 사무장 병원이라 하더라도 환자를 치료하고 보험금을 수령하는 것은 불법행위에 해당하지 않는다고 판시하였다. 의료기관 자체가 부당한 경제적 이익을 얻었을 뿐 의료기관 종사자들이 별다른 이익을 얻지 않은 경우, 리베이트 수수를 금지하는 의료법에 따라 의료기관 종사자들을 처벌할 수 없다는 견해를 밝힌 판결도 눈에 띈다. 그리고 법원은 업무정지처분을 받은 의료기관을 폐업하더라도 같은 장소에서 같은 운영자가 새로이 의료기관을 개설하는 경우 처분의 효과가 미친다고 판시하였고, 의사가 스스로 개설한 의료기관 외에서 진료행위를 할 수 있는 요건에 대하여 판시하였으며, 의료법을 위반한 혐의로 유죄 판결이 확정되기 전에는 이를 이유로 행정처분을 할 수 없다고 판시하였다.

• 전력전자학회논문지
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• 제5권4호
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• pp.386-393
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• 2000

본 논문에서는 고전력, 고주파 응용에 적합한 저 도통손실 특성을 갖는 향상된 양전압 부분 직렬 공진행 DC/DC 컨버터를 제안한다. 제안된 컨버터는 많은 범위에서 주 스위치의 영전압 스위칭을 보장히며 주 스위치의 전류 스트레스 감소에 의해 저도통 손실 특성올 이룬다. 또한 제안된 컨버터의 보조회로는 주 전력 흐름과 분리되어 있어 주 회로의 공진 시간동안 유효 듀티비 감소는 발생하지 않는다. 보조 회로는 인덕터, 커피시터, 다이오드 그리고 과포화 리엑터의 수동 소자들만으로 구성 되어있다. 따라서 향상된 ZVS PSRC는 전체 시스템의 효율과 전류 스트레스 감소면 에서 개선된 특성을 지닌다. 제안한 컨버터의 동작 원리를 자세히 설명하고 그 타당성올 시뮬레이션과 실험을 통하여 검증하고자 한다.

• Journal of Advanced Marine Engineering and Technology
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• 제32권7호
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• pp.1013-1018
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• 2008

For a sequential port fuel injection natural gas engine, its combustion and emission characteristics at low loads are crucial to meet light duty vehicle emission regulations. Fuel injection timing is an important parameter related to the mixture formation in the cylinder. Its effect on the combustion and emission characteristics of a natural gas engine were investigated at 0.2 MPa brake mean effective pressure (BMEP)/2000 rpm and 0.26 MPa BMEP/1500 rpm. The results show that early fuel injection timing is beneficial to the reduction of the coefficient of variation (COV) of indicated mean effective pressure (IMEP) under lean burn conditions and to extending the lean burn limits at the given loads. When relative air/fuel ratio is over 1.3, fuel injection timing has a relatively large effect on engine.out emissions. The levels of NOx emissions are more sensitive to the fuel injection timing at 0.26 MPa BMEP/1500 rpm. An early fuel injection timing under lean burn conditions can be used to control engine out NOx emissions.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2012년도 전력전자학술대회 논문집
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• pp.232-233
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• 2012

This paper presents an effective control scheme for an electric vehicle battery charger where a symmetrical bridgeless power factor-corrected converter and a buck converter are cascaded. Both converters have been popular in industries because of their high efficiency, low cost, and compact size, hence combining these converters makes the overall battery charging system strongly efficient. Moreover, this charger topology can operate at universal input voltage and attain a desired battery current and voltage without ripple. In order to achieve a unity input power factor and zero input current harmonic distortion, the proposed control scheme adopts duty ratio feed-forward control technique in both current and voltage control loop. Additionally, in the current loop, its reference is created by a phase-locked loop (PLL) block, leading to a pure sinusoidal input current although the input voltage waveform is being distorted. The feasibility and practical value of the proposed approach are verified by simulation and experiment with an 110V/60Hz ac line input and 1.5kW-72V dc output of the battery charging system.

• 동아시아식생활학회지
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• 제26권2호
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• pp.181-191
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• 2016

This study aimed to investigate current nutrition education and effective plans for nutrition teachers in schools. Data were collected by a face-to-face questionnaire. Surveyed schools were elementary, middle, and high schools at percentages of 32.4%, 35.1%, and 32.4%, respectively. Percentage of nutrition education was above 90%, whereas off-line education was very uncommon in middle (8.3%) and high schools (27.3%) compared with elementary schools (63.6%), (p<0.05). Satisfaction of nutrition education was also very low in middle (7.7%) and high schools (8.3%) when compared with elementary schools (41.7%), (p<0.05). The main reason for this was due to 'work overload of mealing service (44.4%)' and 'insufficient time of students (25.9%)'. Effective education plans were as follows: beginning of education and education scale were 'elementary school (67.6%)' and 'below 20 people (81.1%)', and the most preferred counterplan was 'development of diverse education programs (4.81 score)' > 'systematic education process (4.76 score)' > 'professional nutrition education (4.51 score)'. Most important duty was 'nutrition education and consultation (51.4%)', although it achieved the lowest satisfaction at a score of 2.46. Overall analysis, demand and awareness of nutrition teachers for nutrition education were very high. Therefore, an institutional strategy and environmental improvements are required by setting up curriculum subjects and developing diverse education programs for systematic nutrition education.

• 한국전자파학회논문지
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• 제9권6호
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• pp.788-801
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• 1998

유성버스트 통신방식은 1000 krn 이상의 장거리 VHF NLOS 데이터 통신 시스템을 가장 경제적인 방법으 로 구현시켜 줄 수가 있다. 그러나 이 방식은 근거리 전송에서는 버스트의 지속시간이 짧아져서 도통율이 열 화함으로 본질적으로 실용에는 부적합한 것으로 알려져 있다. 이 논문에서는 유성 버스트 전송로의 근거리 특성을 해석한 후l 송/ 수신안테나의 빔 패턴이 공간의 hot-spot을 완전히 포용할 수 있도록 함으로써 버스트 의 발생빈도를 증가시키는 동시에 안테나에 유도하는 지상 잡음 전계를 효과적으로 차단함으로서 수신기의 실효 차단전압을 낮추면 시스템의 총 도통율(duty rate)은 크게 개선될 수 있음을 밝혔다. 이 해석결과를 기 초로 하여 특히 근거리 유성 버스트 경로에 적합한 안테나로서 소개구형 공동형 안테니를 개발하였다. 이 안 테니는 지하에 매설하여 사용하는데 이렇게 함으로서 수직방향의 지향성이 개선되고 지상으로부터의 잡음 혼 입이 효과적으로 차단된다. 이 안테나는 3 dB 빔 폭이 $90^{\circ}$에 달하여 앙각 8-$90^{\circ}$로서 근거리 경로의 hot-spot 를 효과적으로 조사(퍼umir뻐tel 할 수가 있는데/ 이것은 대체로 100 krn 이하의 근거리 유성 버스트 경로에 최적합한 조건이다, 지표방향으로의 지향성은 최소로 억제되어 이 방향으로부터 인공잡음의 혼입을 효과적으 로 차단하는데 재래식의 Yagi보다 평균 3 dB 이상 억제된다. 이 안테나를 수신안테나로 사용하여 100 krn 경 로에서 시험통신을 실시한 결과 동일한 조건하에서 4 소자 Ya멍 안테나를 사용한 경우에 비하여 버스트의 발 생빈도와 지속시간이 각각 10 %와 20 % 이상 증가한 것을 확인할 수 있었다.