• The Plant Pathology Journal
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• 제25권3호
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• pp.213-219
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• 2009

An understanding of anthracnose (Colletotrichum acutatum) infections, including the infection of flowers and latent infection early in the season, is necessary to achieve successful control by means of properly timed spraying with a curative fungicide. In the present study, latent anthracnose infection of chili was investigated under greenhouse and field conditions in 2007-2008. Flowers on greenhouse-grown seedlings were infected and 11% of the young fruits subsequently showed symptoms of anthracnose. Apparently healthy-looking green peppers obtained from unsprayed fields or an organic market also exhibited symptoms of anthracnose after 4 days of incubation under high moisture conditions at $25^{\circ}C$; less than 1% of the peppers were found to be latently infected. To determine the natural timing of infection in the field, 3,200 fruits were wrapped in paper bags and then selectively unwrapped and examined for signs of infection. Field experiments were conducted at Suwon (cvs. Yokkang, Manitta, Olympic) and Asan (cv. Chunhasangsa) in 2008. The 7- to 10-day wrapping periods were July 25-31, July 31-August 7, August 7-15, August 15-24, and August 24-September 3. The 1-to 2-month wrapping periods were from July 4, July 31, and August 15 until harvest (Sept. 3). The controls consisted of 1,712 field-grown non-wrapped fruits. The rates of infection on the various cultivars were Yokkang 55%, Manitta 37%, Olympic 55%, and Chunhasangsa 20%. A distinct period in which anthracnose infection suddenly increased could not be identified; however, attempts to guess the approximate timing of field infection showed that 0-39% of the plants had latent infections, while depending on the cultivar, 8-14% of the plants examined in August and 4-13.5% of the those examined during May-July showed symptoms of infection. Delaying fungicide spraying by 24 and 48 h after artificial infection decreased the rates of infection by 10% and 25-30%, respectively. Chemical control of anthracnose based on a forecasting model should be considered starting from the transplanting stage, with spraying within a day after warning and care being taken not to latently infect apparently healthy pepper fruits.

• 한국지구과학회지
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• 제22권1호
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• pp.40-46
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• 2001

기상청에서 덕적도와 칠발도에 설치한 해양기상 관측부이 자료를 이용하여 해양 및 대기 특성과 해양-대기간의 열교환을 살펴보았다. 각 관측지점에서의 일평균 현열속 및 잠열속은 벌크공기역학법을 적용하여 계산하였다. 표층수온은 기온과 같이 뚜렷한 연주기를 보이지만, 1달 정도 시간지연을 가진다. 해면기압은 7월에 가장 낮았고 겨울에 가장 높았으며, 습도는 5-8월 사이 비교적 높았다. 풍속은 가을과 겨울에 평균 5m/s 이상으로 강한 편이었다. 현열속 분석결과 가을부터 겨울에 걸처 해양의 열손실이 두드러졌으며, 봄과 여름에는 반대로 대기에서 해양으로의 약한 열전달이 이루어져 연중 순현열속은 해양에서 대기로의 열전달을 보여주었다. 잠열속 분석결과 봄에서 여름까지 대기의 열손실이 나타나지만, 그 외 기간에는 해양의 열손실이 월등히 크게 나타났다. 현열속과 잠열속의 크기를 비교해 볼 때,1-2월을 제외하고는 전반적으로 현열속보다 잠열속에 의한 해양의 열손실이 우세함을 알 수 있었다. 관측지점별로 분석한 열속의 크기와 변동폭은 대체적으로 덕적도에서 더 크게 나타났다. 일정 기간을 선정한 사례연구에서, 1998년 5월사례의 경우 현열속과 잠열속 모두 칠발도에서 더 크고, 1996년 11월 사례의 경우에는 덕적도에서 훨씬 크게 나타났다.

• 대한전기학회논문지
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• 제33권11호
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• pp.440-446
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• 1984

This thesis investigates the quantitative aspect of epidemic phenomena utilizing the analytical method of discrete time systems based on the theory of Markov processes. In particular, the pattern on the epidemic character of Influenza was analyzed by the mathematical model of Influenza system, which is derived according to the ecologic relationship between five epidemiolgic states of individuals. The quantitative aspects of the model was characterized by digital computer simulations. The main results were obtained as follows: 1) A Markovian model of influenza system represents accurate spead curve. 2) The latent period of influenza has the standard deviation of 1.98 and also the incubation period is 2.68. 3) If the value of susceptibilities in the pre-epidemic period is less than 20% of the population, the epidemic will occur sporadically. 4) The initial value of susceptibilties obtained by this markov theory is less about 10% of total population than the obtained value according to the deterministic model.

• 한국보건간호학회지
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• 제10권1호
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• pp.12-22
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• 1996

Currently. exchanges of industrial workers between countries are more active than ever. and the problem of AIDS in connection with the operation of preventive educational programs has reached a point where the issue cannot be limited to native people alone any more. Based on such judgement. this research has been carried out to provide basic study materials by grasping the latent factors representing the difference between countries in the levels of right knowledge. attitude and behavior with respect to AIDS maintained by workers who have grown in different social and cultural living background. During the period from Apr. 1. 1995 to Jun. 30. questionnaires. written both in Korean and English, were distributed to Korean and Malaysian employees working at certain Korean video manufacturers. and the results of replies. given by 80 workers who were analyzed through matched sampling· method where ages and sex matched by country. were used as the research materials. The gathered materials were analyzed through the SPSS package t-test. ANOVA. factor analysis and multiple stepwise regression methods. and the following results were obtained. 1. The 2 extracted latent factors could be named 'common. social' knowledge factor and 'in-depth. psychological' knowledge factor respectively. 2. The percentile points of 'external. social' knowledge factor. in the case of Korean workers. howed 90.0 at average. a figure 13.75 points higher than those of Malaysian workers. 76.25. On the other hand. the percentile points of the 'in-depth. psychological'knowledge factor showed 70.80 at average in the case of Korean workers. a figure 7.47 points lower than those of Malaysian workers. 78.33. Meanwhile. the difference in percentile points between the 2 latent factors was 8.54 at average. indicating that the points of 'in-depth. psychological' knowledge factor was lower than those of the 'external. social' knowledge factor. 3. As for Korean workers. the percentile points of the 'in-depth. psychological' knowledge factor showed higher points in office workers than in non-office workers. and such variables exhibited in the position of workers can explain the $7\%$ of the latent factor. The percentile points of the 'in-depth. psychological' knowledge factors. in the case of Malaysian workers. showed higher points in groups who had religion than in groups who did not. and higher points in groups who obtained information from newspapers than in groups who obtained from televisions or other sources; and with these 2 variables. $26\%$ of this latent factor can be explained. The results. of analysis described so far suggest that while Korean workers possessed general level of knowledge on AIDS. they had low level of practical knowledge as far as its depth is concerned. and that they had social prejudice on patients as well as on the AIDS infection route. In addition. because the overall knowledge level of Malaysian workers. is lower than that of Korean workers. it suggests that separate programs intended for Malaysian workers are required prior to executing integrated programs.

• 한국산학기술학회논문지
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• 제21권1호
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• pp.468-476
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• 2020

본 연구의 목적은 자녀 출생부터 5년까지의 아버지 양육참여의 변화 궤적에 따른 잠재집단을 확인하고, 확인된 잠재집단에 따라 자녀의 문제행동 및 어머니의 양육스트레스, 부부갈등, 결혼만족도, 우울에 차이가 있는지 확인하는 것이다. 한국아동패널 1차년도(2008년)에서 5차년도(2012년)까지 자료의 1,316명 데이터를 분석하였으며, 잠재계층성장분석과 다변량분산분석을 활용하였다. 분석 결과, 첫째, 2차 함수 모형에 기초한 잠재계층성장분석을 통해 어머니가 지각한 아버지의 양육참여 변화 유형은 '최저수준 무변화형 집단', '중수준 감소형 집단', '중상수준 변동형 집단', '최상수준 변동형 집단'의 네 유형이 확인되었다. 본 연구에서 확인한 잠재집단의 특징은 아버지 양육참여 수준이 가장 낮은 집단의 경우 양육참여 수준의 변화가 잘 나타나지 않으며, 아버지의 양육참여 수준이 높은 집단의 경우에도 자녀가 네 살이 되는 시점부터는 양육참여 수준이 감소한다는 것이다. 둘째, 아버지의 양육참여 수준이 지속적으로 감소하는 '중수준 감소형 집단'이 아버지 참여수준이 제일 높은 '최상수준 변동형 집단'보다 자녀의 외현화 문제행동이 더 많은 것으로 나타났다. 셋째, '최저수준 무변화형 집단'과 '중수준 감소형 집단'이 '중상수준 변동형 집단'과 '최상수준 변동형 집단'보다 어머니의 양육스트레스, 부부갈등, 우울 수준은 높은 반면, 결혼만족도는 '최상수준 변동형 집단', '중상수준 변동형 집단', '중수준 감소형 집단', '최저수준 무변화형 집단' 순으로 높은 것으로 확인되었다. 본 연구는 아버지 양육참여의 변화 특성이 자녀뿐 아니라 어머니의 삶에 많은 영향을 미칠 수 있음을 시사하며, 아버지 양육참여를 촉진하기 위한 사회적 노력과 정책적 개입이 필요함을 시사한다.

• 한국산업보건학회지
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• 제30권1호
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• pp.67-74
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• 2020

Objectives: Previous study has shown that the positive rate of latent tuberculosis infection(LTBI) among former workers in dusty environments was higher than that among high-risk groups of tuberculosis(TB). The objective of the present study was to identify the development of active TB among former workers in dusty environments diagnosed with LTBI. Methods: Between January 2015 and May 2017, 796 former workers in dusty environments who had been subjects of epidemiology research for work-related chronic obstructive pulmonary disease(COPD) had received the QuantiFERON-TB® Gold In-Tube(QFT-GIT) from the Institute of Occupation and Environment(IOE) under the Korea Workers' Compensation and Welfare Service(KCOMWEL). Among them, 437 participants who received a health examination for work-related pneumoconiosis between January 2015 and December 2018 were selected as study subjects. Active TB was defined as a positive result for active PTB and non-tuberculosis mycobacteria infection in the result of the Pneumoconiosis Examination Council's assessment by KCOMWEL. Results: A total of 437 subjects were followed up for 2.1 years. Four of them(4/437, 0.9%) developed active TB during the follow-up period. The attack rate of active TB among subjects who were diagnosed LTBI positive and those who were diagnosed LTBI negative were 0.9%(3/320) and 0.9%(1/115), respectively. Conclusions: Most previous studies reported that the attack rate of the development of active TB in subjects who had been diagnosed LTBI positive was higher than that among subjects who had been diagnosed LTBI negative. To the contrary, the present study found that the rate of developing active TB among former workers in dusty environments diagnosed as LTBI positive was not higher than that in those who were diagnosed LTBI negative.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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• pp.289-292
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• 2008

Recently, several satellite data analyses projects and numerical weather prediction (NWP) reanalysis projects have produced the ocean surface Latent Heat Flux (LHF) data sets in the global coverage. Comparisons of these LHF data sets showed substantial discrepancies in the LHF values. Recently, the increase of LHF in during 1970s-1990s over the global ocean is shown by the LHF data that have been developed at the Objective Analyzed Air-Sea Fluxes (OAFlux) project. It is interesting to investigate the existence of the increase of LHF over a global ocean in the other LHF products. It is interesting to investigate the existence of the increase of LHF over a global ocean in the other LHF products. In this study, we assessed the consistencies and discrepancies of the inter-annual variability and decadal trend for the period 1988-2005 among six LHF products ((J-OFURO2, HOAPS3, IFREMER, NCEP1,2 and OAFlux) over the global ocean. As results, all LHF products showed a positive trend. In particular, the positive trend in satellite-based data analyses (J-OFURO2, HOAPS3, IFREMER) is larger than that in reanalysis products (NCEP1/2). Also, the consistencies and discrepancies are shown on the spatial patterns of the LHF trends across the six data sets. The positive trend of LHF is remarkable in the regions of western boundary currents such as the Kuroshio and the Gulf Stream in all LHF data sets. But, the discrepancies are shown on the spatial patterns of the LHF trends in tropics and subtropics. These discrepancies are primarily caused by the differences of the input meteorological state variables, particularly for the air specific humidity, used to calculate LHF.

• Asian Pacific Journal of Cancer Prevention
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• 제16권8호
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• pp.3167-3172
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• 2015

Background: Understanding the history of human papilloma virus (HPV) infection is important for interpretation of a positive HPV DNA screening test, future work-up and treatment. We investigated the transition of HPV DNA test results in Korean women, and analyzed the association of cytology result with transition type. Materials and Methods: We retrospectively reviewed annual HPV DNA test results for 5,274 subjects between January 2005 and December 2012. Each subject had a minimum of five annual tests over the eight-year period. Based on the pattern of results, the transition type for each subject was assigned to one of the following: negative, persistent, latent, transient, and unclassifiable. Associations of cytology results with the HPV DNA transition types, number of positive results, and the durations of positive results were also analyzed. Results: The proportion of abnormal cytology findings decreased in the following order of transition patterns: persistent, latent, transient, and negative. Among transient patterns, a duration of three years or more significantly correlated with cytology results of non-high grade squamous intraepithelial lesion (HSIL; p<0.001). In the persistent group, duration of five years or more correlated with both non-HSIL and HSIL (p<0.001). Latent group showed no correlation with duration. Irrespective of patterns, having five or more positive results was significantly associated with HSIL (p<0.001). Conclusions: Our findings may contribute to better understanding of HPV infection, interpretation of HPV DNA screening results, and prediction of prognosis according to transition type.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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• pp.162-167
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• 2011

Thermal storage plays an important role in building energy saving, which is greatly assisted by the incorporation of latent heat storage in building materials. A phase change material is a substance with a high heat of fusion which, melting and solidifying at a certain temperature, can be storing and releasing large amount of energy. Heat is stored or released when the material changes from solid to liquid. Integration of building materials incorporating PCMs into the building envelope can result in increased efficiency of the built environment. The aim of this research is to identify thermal performance of PCMs impregnated building materials which is applied to interior of building such as gypsum and red clay. In order to analyze thermal performance of phase change materials, test-cell experiments and simulation analysis were carried out. The results show that micro-encapsulated PCM has an effect to maintain a constant indoor temperature using latent heat through the test-cell experiments. PCM wallboard makes it possible to reduce the fluctuation of room temperature and heating and cooling load by using EnergyPlus simulation program. Phase change material can store solar energy directly in buildings. Increasing the heat capacity of a building is capable of improving human comfort by decreasing the frequency of indoor air temperature swings so that the interior air temperature is closer to the desired temperature for a long period of time.

• 한국약용작물학회지
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• 제8권4호
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• pp.319-326
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• 2000

삽주의 근경은 한방에서 중요한 생약재인 백출로 이용되고 있다. 그러나 국내의 백출수급은 자연산 채취 또는 수입품에 주로 의존하고 있기 때문에 시급히 재배가 이루어져야만 한다. 본 시험은 삽주재배에 관한 정보를 제공하고자 정식전 $GA_3$를 농도와 침지기간을 달리하여 처리한 후 삽주의 생장, 형태 및 수량을 조사하였으며 그 결과를 요약하면 다음과 같다. 1. $GA_3$ 처리는 무처리에 비하여 줄기수, 잠아수, 생체중을 증가시켰다. 2. $GA_3$ 처리시 50 ppm에서는 줄기수, 100 ppm에서는 잠아수 및 근경생체중, 250 ppm에서는 지상부 생체중이 가장 많았다. 3. $GA_3$ 처리기간에 따라서는 1일 처리시에는 엽수, 뿌리수, 초장, 지상부와 뿌리의 생체중이, 2일 처리시에는 줄기수, 잠아수, 근경생체중이 가장 높았다. 4. $GA_3$ 처리에 따른 단위면적당 수량은 100 ppm으로 1일 처리할 경우 가장 높게 나타났다.