• 천문학회보
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• 제35권2호
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• pp.34.1-34.1
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• 2010

Studies suggest that activities in luminous AGNs, residing mostly in early-type galaxies, are triggered by merging. However, the observational evidence for the connection between mergers and AGN activity is not clear yet because tracer of the past merging activities such as tidal tail, shell are often too faint. To see if we can reveal the merging features with a small telescope, we observed an AGN, MARK 478, at z=0.077 with long exposure time (7550 seconds) in V filter at Maidanak observatory. Our 2-D fitting analysis shows that the host galaxy of MARK 478 has the bulge to the total luminosity ratio of 0.3. And the residual image, after subtracting point spread function (PSF), bulge and disk components, shows that the host galaxy has an arm-like feature that could be a spiral arm or a feature from minor merging. We also show that the structural parameters obtained from our 2-D fitting match well with those derived from HST image. The promising result suggests that studies of low redshift AGN host galaxies are possible with data from a small telescope. In order to allow a statistical analysis, we hope to expand our sample size in future.

• 자원ㆍ환경경제연구
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• 제19권1호
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• pp.3-21
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• 2010

발전부문의 부분적인 민영화 이후 전력의 도매가격은 한계가격(system marginal price)으로 결정되고, 이 가격은 발전사의 발전량에 의해서 달라지기 때문에 발전사 입장에서는 완전히 외생적으로 결정되는 가격이라 보기 어렵다. 본고는 Harrison(1994), Levinsohn(1993) 등이 개발한 시장의 완전경쟁성이 유지되지 않을 때에도 기업의 생산성 변화와 규모수익성, 마크업률 등을 분석할 수 있는 모형을 한국의 화력발전소 자료에 적용하였다. 분석결과 규모수익은 거의 없으며, 마크업률은 발전소의 사용 에너지 유형에 따라 크게 다른 것으로 나타났다. 아울러 완전경쟁시장을 가정하는 통상적인 분석법에 비해 발전소의 생산성 변화율 계측치도 상당한 정도 차이를 보였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제13권4호
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• pp.2223-2242
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• 2019

Distance Vector-Hop (DV-Hop) algorithm is widely used in node localization. It often suffers the wormhole attack. The current researches focus on Double-Wormhole-Node-Link (DWNL) and have limited attention to Multi-Wormhole-Node-Link (MWNL). In this paper, we propose a security DV-Hop algorithm (AMLDV-Hop) to resist MWNL. Firstly, the algorithm establishes the Neighbor List (NL) in initialization phase. It uses the NL to find the suspect beacon nodes and then find the actually attacked beacon nodes by calculating the distances to other beacon nodes. The attacked beacon nodes generate and broadcast the conflict sets to distinguish the different wormhole areas. The unknown nodes take the marked beacon nodes as references and mark themselves with different numbers in the first-round marking. If the unknown nodes fail to mark themselves, they will take the marked unknown nodes as references to mark themselves in the second-round marking. The unknown nodes that still fail to be marked are semi-isolated. The results indicate that the localization error of proposed AMLDV-Hop algorithm has 112.3%, 10.2%, 41.7%, 6.9% reduction compared to the attacked DV-Hop algorithm, the Label-based DV-Hop (LBDV-Hop), the Secure Neighbor Discovery Based DV-Hop (NDDV-Hop), and the Against Wormhole DV-Hop (AWDV-Hop) algorithm.

• 융합신호처리학회논문지
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• 제7권3호
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• pp.122-129
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• 2006

본 논문에서는 고차 비구면 렌즈의 성능 평가를 위해, Fizeau 형 위상 천이 간섭계 (FPSI) 시스템을 제안한다. 제안된 Fizeau 형 위상 천이 간섭계 시스템은 광학부와 신호처리부로 나뉘며 이는 하드웨어 운용 프로그램을 통해 구동된다. 또한, 제안된 시스템으로 획득된 간섭무늬를 해석하기 위해, 위상 천이 알고리즘을 적용한 간섭무늬 해석 프로그램을 개발하였다. 본 논문에서 제안한 FPSI 시스템의 측정 결과는 업계 표준으로 사용되고 있는 Zygo 사의 간섭계 측정 장치인 Mark IV와 직접 비교함으로써 그 타당성을 입증하였다. 평가된 고차 비구면 렌즈의 표면 오차에 대한 PV(Peak-to-Valley) 및 RMS 값은 각각 0.845 wave 및 0.1871 wave로 측정되었고 Mark IV 와 비교한 결과, 측정 오차는 각각 ${\lambda} /100$ 이하로 계산되었다. 또한, 비구면 렌즈의 성능평가 시스템의 반복능도 ${\lambda}/100$ 이하의 신뢰할 만한 결과를 얻었다.

• 대한지역사회영양학회지
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• 제18권4호
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• pp.324-332
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• 2013

The purpose of this study was to investigate middle school students' perception of environment-friendly agricultural products (EAPs) and the degree of confidence about the certification mark. Questionnaires were distributed to 444 students of 6 middle schools located in Daegu, and a total of 416 responses were used for analysis. 28.6% of the respondents were using EAPs at home, and 62.0% of respondents didn't know whether to use EAPs at home. The 6 items representing the perception of EAPs were analyzed, resulting in 2 distinct dimensions-'benefits of EAPs' and 'attitude toward EAPs'. Regarding Benefits of EAPs, the score of 'EAPs better for health' was the highest, followed by 'EAPs have higher quality', 'EAPs were better for environmental protection', respectively. The proportion of students responded that 'the amount of pesticides should be reduced gradually' was 65.5% and only 3.4% for 'current level of pesticide use is not a problem'. There were significant differences between male and female students with regard to an interest in EAPs (p < 0.05) and opinion on the use of pesticides (p < 0.05), while no significant difference was found between groups with different education level of mothers. The respondents who use EAPs at home showed significantly higher scores with attitude toward EAPs (p < 0.001), and higher response rate for 'pesticides should not be used even if the price increases' (p < 0.05). Degree of confidence about the EAPs certification mark also affected students' perception of EAPs (p < 0.001). Our results indicate the importance of education for students on EAPs to enhance students' attitude towards EAPs and improve school meal satisfaction.

• 한국기술혁신학회:학술대회논문집
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• 한국기술혁신학회 2003년도 춘계학술대회
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• pp.31-43
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• 2003

최근 ICT(Information Communication, Telecommunication)기술이 변화함에 따라 많은 산업에 있어 변이가 이루어지고 있으며 기술혁신이론에서는 이러한 변화의 추동요인에 주목하고 있는 실정이다. 이러한 배경하에서 본 연구는 ICT 산업혁신체제(Sectoral Innovation Systems)의 역동성을 규명하기 위하여 미국 특허 데이터(USPTO)를 중심으로 산업을 구성하고 정의하는 기초 구성체(Basic elements)를 정량적으로 측정하고자 대리변수를 개발하여 활용하였다. 본 연구의 결과로서 지난 30년 동안 ICT 산업 전반에 걸쳐 기술적 체제(Technological Regimes), 기술간 핵심적 연결(Key links)과 산업을 지탱하고 있는 이종촉진자(Heterogeneous agents)의 혁신패턴에 있어서 변화가 발생하고 있으며 특히 ICT 전체 산업에 걸쳐 슘페터 혁신패턴이 Mark 1에서 Mark 2로의 변이가 발생하고 있음을 보여주는 결과를 얻을 수 있었다. 본 연구의 방법 및 결과를 비추어 볼 때, 본 연구의 의의는 특허 데이터를 활용하여 기업과 기술적 관점에서 특정 시점이 아닌 1970년 이후 발생하는 ICT 산업혁신체제의 역동성에 대한 전체적인 그림을 제공하는데 있다.

• 대한교통학회지
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• 제29권3호
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• pp.115-122
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• 2011

이 논문은 자동차의 급제동시 발생되는 스키드마크(skid mark, 활주거리)를 통해 제동직전 속도(Pre-braking Speed)를 정확히 산정하기 위한 방법론을 제시하고자 한다. 운전자는 전방에 위급한 상황이 전개되거나 불의의 사고에 처하게 되었을 경우 통상 급제동조치를 취하게 되며, 정지거리에 따라 사고를 당할 수도 있다. 자동차의 정지거리에 있어서 영향을 끼치는 요인은 운전자의 인지반응시간, 자동차 제동장치의 성능, 노면의 상태 등을 꼽을 수 있으나, 가장 중요한 요인은 제동직전 속도(Pre-Braking Speed)라고 할 수 있다. 현재 교통사고의 조사분야에서는 skid mark의 길이에 근거한 활주직전 속도(Preskidding Speed)를 산정하여 과속 여부를 판단하고 있으나, 정확한 사고원인 규명을 위해서는 불완전제동시간 동안 감속된 속도를 고려한 제동직전 속도의 산정이 필요할 것으로 판단된다. 따라서, 본 연구에서는 교통사고시 자동차의 정확한 속도정보를 산정하기 위한 방법을 제안하고자 하며, 또한 이 연구가 향후 교통안전차원에서 자동차의 특성을 이해하는데 있어서 일조할 수 있기를 기대한다.

• 한국해양공학회지
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• 제13권3호통권33호
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• pp.29-35
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• 1999

At the design of Mark III membrane type LNG tank, an analytical and experimental approach on the fatigue strengths of membrane and its welds are very important in order to assist designers and surveyors. In this study, fatigue tests of lap weld of Mark III membrane type LNG tank were carried out and cumulative damage factor was calculated in order to estimate the fatigue life by probability density function and rule methods. It contained the following tests and reviews : 1) The fatigue tests of lap weld of stainless steel according to statistical testing method recommended by JSME, 2)Preparation of S-N curve for lap welds considering the statistical properties of the results of fatigue tests. 3) Procedure for estimating the initiation life of fatigue crack of lap welds under variable loads by the rule lf classification society and probability density function, 4) Guideline for inspection of lap welds fo membrane type LNG tank.

• 재활간호학회지
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• 제5권1호
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• pp.71-85
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• 2002

The purpose of study was to find out the relation ship between health perception and health status of clinical nurses. It also identified factors that related to health perception and health status of clinical nurses. The research design was descriptive correlational study. The subjects were consisted of 289 clinical nurses at the university hospital in Pusan. The data were collected from Feb. 12th to Feb. 28th, 2001 by self reporting structured questionnaires. The instruments used for this study were health perception questionnaire developed by Ware and Cornell Medical Index modified by Nam Ho-Chang (1965) for measuring health status. The data were analyzed by SPSS/PC+ program using frequency, percentage, mean, mean mark, standard deviation, t-test, ANOVA, Scheffe test, and Pearson's correlation coefficient. The results of this study were as follows. 1. The mean score of the health perception was $94.70{\pm}8.93$(range : 29-145), which the item mean mark score was $3.27{\pm}$0.31(range 1-5). The score of subarea of the health perception was the highest score in health concern ($4.57{\pm}0.58$) and the lowest score in rejection of sick role($2.94{\pm}0.32$). 2. The mean score of the health status was $102.83{\pm}7.61$(range: 57-114), which the item mean mark score was $1.80{\pm}0.13$ (range : 1-2). The mean mark score of the physical health status was $62.55{\pm}5.35$($1.69{\pm}0.14$) and the mental health status was $40.28{\pm}3.51$($1.83{\pm}0.16$). 3. There were statistically significant difference in the score of health perception according to the presence of disease(F=4.607, P=.011), job satisfaction (F=12.242, P=.000), and job place(F=2.838, P=.038). 4. There were statistically significant difference in the score of health status according to the age(F=3.164, P=.007), presence of leisure time(F=4.308, P=.039), presence of diseases(F=3.215, P=.042), job experience(F=9.064, P=.000), job satisfaction(F=7.182, P=.001), job place (F=5.638, P=.001), job position (F=3.900, P=.021). 5. Health perception of clinical nurse was shown to be positively related to health status(r=.543, p=.000). In conclusion, health perception of clinical nurse working at the university hospital was relatively high, and health status was fine. And the more health perception was high, the more health status was high. Therefore, the health promotion program for clinical nurses, should included health perception.

• 한국막학회:학술대회논문집
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• 한국막학회 2000년도 제12회 심포지움
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• pp.3-19
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• 2000

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