• 한국환경농학회지
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• 제37권1호
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• pp.28-33
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• 2018

수박 휴작기에 풋거름 작물로 헤어리베치와 호밀을 재배한 후 토양으로의 환원이 후작물 수박의 생육과 수량 그리고 토양의 질산태질소 함량에 미치는 영향을 구명하고자 하였다. 파종 후 151일간 재배한 후에 헤어리베치와 호밀의 토양 질소 환원량은 각각 79 kg/ha와 88 kg/ha였다. 헤어리베치와 호밀은 시설하우스 한 동씩 두 동의 면적에 풋거름 작물구, 풋거름작물에 요소 25%, 50%, 75% 처리구, 요소 100% 등 5처리를 각각 두었다. 수박의 생육은 각각의 헤어리베치 및 호밀 처리에서 동일한 생육을 나타냈고 수박의 수량에서도 처리간의 통계적인 유의성은 없었다. 토양의 질산태 질소함량은 수박 정식 후 재배일수가 증가할수록 지속적으로 감소하여 정식 후 75일째에 가장 낮은 함량을 나타내었는데 호밀처리구는 호밀만 투입만 처리가 52 mg/kg으로 가장 낮았고, 헤어리베치 처리간 비교에서도 마찬가지로 헤어리베치만 공급한 처리가 가장 낮은 44 mg/kg이었다. 헤어리베치와 호밀 등 녹비작물만의 투입으로도 수박의 재배기간 동안에 토양의 질산태 질소가 40 mg/kg 이상으로 존재하여 화학비료의 추가적인 시비 없이도 동일한 생육을 보인 것으로 판단되었다. 하지만 수박의 수량과 재배기간에의 토양 중 질산태질소와의 관계에 대한 추가적인 연구가 필요할 것으로 사료된다.

• Ecology and Resilient Infrastructure
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• 제7권1호
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• pp.1-14
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• 2020

하천과 홍수터 생태계에서 생물지형학 연구는 폭 넓은 시공간 차원에서 생물계와 수문-지형체계 사이의 복잡한 다중관계를 다루어 왔다. 본 총설에서는 하천에서 (1) 생물과 수문지형 조건의 다자간 관계, (2) 생물다양성과 서식처 이질성의 관계, (3) 생태계 유형에 대한 교란의 영향에 대하여 설명함으로써 하천지형생물학의 범위와 과정을 논의하였다. 시간적으로 하천의 생물지형 복합체는 지형, 선구, 생물지형 및 생태적 단계의 순서로 전환이 된다. 공간적으로 물 흐름과 유사 분포가 식생과 상호작용하여 하도 지형의 변화가 일어난다. 이렇게 형성된 하천의 공간적 이질성은 하안의 생물종다양성을 증가시킨다. 그러나 댐 하류 하천에서는 서식처 유형과 조건이 심각하게 훼손되어 생물다양성이 저하된다. 우리나라의 하천에서는 최근 국지적 교란과 전 지구적 기후변화로 하안 식생이 번무하고 특히 외래종이 빠르게 정착하고 있다. 따라서 급격한 기후변화와 인류에 의한 압박의 시대에서 하천 생물과 수문지형 조건 사이의 상호 관계를 이해하는 것이 더욱 중요할 것으로 생각된다. 이 총설에서 논의한 하천 생물지형 개념틀은 우리나라 하천의 생태적 관리와 복원에 기여할 것으로 기대된다.

• 한국토양비료학회지
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• 제26권3호
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• pp.155-159
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• 1993

토성(土性)과 토심별(土深別) 토양의 용적밀도(容積密度)나 pH, 유기물함량(有機物含量)의 평균치(平均値)를 구하고 상호관계를 구명하여 답토양 개량을 위한 기초자료를 얻고자 전국(全國) 벼 다수확답과 어린모 재배단지 및 인근답등 124개 포자에서 현지(現地) 시료를 표토와 심토로 구분하여 각각 3반복으로 채취하여 분석한 결과는 다음과 같다. 1. 답토양 표토(表土)와 심토(心土)의 평균 토성은 양토(壤土)이었다. 2. 용적밀도는 표토에서 모래와 미사(微砂), 심토에서는 모래, 미사, 미사(微砂)+점토(粘土). pH 및 유기물함량이 1%수준에서 유의성(有意性)이 있었다. 3. 점토(C) 및 미사+점토(S+C)함량과 유기물함량(OM)을 가지고 용적밀도(容積密度)(Y)를 구할 수 있는 회귀식을 구하였다. 표토(表土)에서는 Y= 1.365 + 0.006C - 0.003(S+C) - 0.034OM (R = 0.067*)으로, 심토(心土)에서는 Y= 1.548 - 0.002C - 0.0007 (S+C) - 0.036OM (R=0.122**)로, 수식화(數式化)할수 있었다.

• 한국보건간호학회지
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• 제18권2호
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• pp.312-329
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• 2004

This study was examined 718 workers who had consistent blood pressure results in 2001 and 2002 general health examinations that were held at a work places managed by a health care agency in Seoul. Significant results are found as follows by analysing SPSS 11.0 on the result of self-recorded questionnaires investigated from Mar 1, 2003 to April 30, 2003. 1. A sampled healthy group and a sampled unhealthy group had significant differences in four variables out of possible nineteens that are sex, age, marriage and occupation. The unhealthy group had more males than females, more aged (over 50 years old) than youngers (under 50 years old), more married than singles, more manufacturing workers than non-manufacturing workers. In the case of systolic blood pressure, as the healthy group had 16.52mmHg while that of the other group had 149. 58mmHg, 33.06mmHg of difference between those groups were detected. In the case of diastolic blood pressure, 74.93mmHg of the healthy group and 96.53mmHg of the unhealthy group yielded 21.60mmHg of difference between them. This result implies that a guidance of health care is required to be aware of 20-30mmHg volatility in blood pressure rate or to understand and treat properly own blood pressure. as it is difficult to detect hypertension in early stage due to no initial symptom. According to the result. an establishment of management system of workers, companies and health care agencies is required for consist health care. 2. In terms of risky habits to health, the unhealthy group had more proportion of past smokers, over-twice-a-week drinkers, people with higher obesity rate. However, in terms of excercise, the proportion of regularly exercising people is higher in the unhealthy group while that of non-exercising people is higher in the healthy group. On the other hand. the average grade of health practicing behaviour in two groups are not significantly different as the health group had 3.00 out of possible 6.00 while the other had 3.10. This result means that as workers are not interested in health practicing behaviour. health promoting programmes must be developed in such a way of various method of motivations and incentives. Particularly this implies that distortional objectives of exercises should be readjusted through health guidance. 3. Systolic blood pressure in the healthy group can be explained by sex and the obesity rate while that in the unhealthy group can be explained by subjective health awareness and the obesity. Diastolic blood pressure in the healthy group can be explained by sex and the obesity rate like the former. The obesity rate was significant variable affecting the blood pressure of both groups, and particularly the effect to the unhealthy group was remarkably higher than that to the healthy group. Therefore, this research identified that the health care on the blood pressure of workers is not only limited to hypertension patients, but also extended to all workers. In order for consistent care, an establishment of management system of workers, companies and health care agencies is required.

• 한국환경과학회지
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• 제4권5호
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• pp.28-28
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• 1995

The aim of the present study is to investigate the interannual variabilities of the East Asia monsoon rainfall associated with the global sea surface temperature anomaly(SSTA). For this study, the summer rainfall(from June to August) over the twenty-eight period of 1961-1988 were analyzed with being divided by nine-subregions over East Asia including Korea, China and Japan. From the analysis of the principal modes explaining the interannual variation, the interannual variabilities of summer rainfalls in South Japan and Korea are larger than those of the other subregions of the East Asia. There is a strong negative correlation between the summer rainfalls of south China and Korea. In this study, the relationship between the summer monsoon of each subregion and SSTs of the tropical NINO regions, of western Pacific warm pool, and of the subtropical ocean were investigated. The longitudinal sections of the lagged cross correlations of the summer rainfal1 anomaly in (a) Korea and (b) south China, and the monthly SSTA in the equatorial(averaged from 65 to 6N) Pacific were analyzed. The negative maximum correlation pattems of Korea''s stammer rainfal1 and SSTs over the eastern Pacific is transfered to positive maximum conrlation over central Pacific region with a biennial periodicity. In South China, the significant positive correlations are found at -12 month lag over the eastern Pacific and maximum negative correlation at 16 month lag over the central Pacific with the quasi-biennial oscillation. But the correlation coefficient reverses completely to that in Korea. In order to investigate the most prevailing interannual variability of rainfall related to the favored SSTA region, the lagged cross correlations between East Asia rainfall and SSTs over the moO regions(NINO 1+2(0-105, 90W-80W), NINO 3(5N-5S, 150W-90W), NINO 4(5N-5S, 160E-l50W) and the western Pacific worm pool (5N-5S, 120E-l60E) were analyzed. Among the lagged cross-correlation cycles in NINO regions, the maximum correlations for the negative lagged months prevail in NINO 1+2 and NINO 3, and the cross correlations for the positive lagged months NINO 4. It is noteworthy that correlation between the western Pacific warm pool SSTA and the monsoon rainfall in Korea and South China have the maximum value at negative 4 month lag. The evolution of the correlation between the East Asia monsoon rainfall and SSTA is linked to the equatorial convective cluster and related to northward propagating situation, and raising the possibility that the East Asia monsoon precipitation may be more fundamentally related to the interaction of intraseasonal oscillations and the sub-regional characteristics including the surface boundary conditions and the behavior of climatological air mass.

• 한국환경과학회지
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• 제4권5호
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• pp.413-426
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• 1995

The aim of the present study is to investigate the interannual variabilities of the East Asia monsoon rainfall associated with the global sea surface temperature anomaly(SSTA). For this study, the summer rainfall(from June to August) over the twenty-eight period of 1961-1988 were analyzed with being divided by nine-subregions over East Asia including Korea, China and Japan. From the analysis of the principal modes explaining the interannual variation, the interannual variabilities of summer rainfalls in South Japan and Korea are larger than those of the other subregions of the East Asia. There is a strong negative correlation between the summer rainfalls of south China and Korea. In this study, the relationship between the summer monsoon of each subregion and SSTs of the tropical NINO regions, of western Pacific warm pool, and of the subtropical ocean were investigated. The longitudinal sections of the lagged cross correlations of the summer rainfal1 anomaly in (a) Korea and (b) south China, and the monthly SSTA in the equatorial(averaged from 65 to 6N) Pacific were analyzed. The negative maximum correlation pattems of Korea's stammer rainfal1 and SSTs over the eastern Pacific is transfered to positive maximum conrlation over central Pacific region with a biennial periodicity. In South China, the significant positive correlations are found at -12 month lag over the eastern Pacific and maximum negative correlation at 16 month lag over the central Pacific with the quasi-biennial oscillation. But the correlation coefficient reverses completely to that in Korea. In order to investigate the most prevailing interannual variability of rainfall related to the favored SSTA region, the lagged cross correlations between East Asia rainfall and SSTs over the moO regions(NINO 1+2(0-105, 90W-80W), NINO 3(5N-5S, 150W-90W), NINO 4(5N-5S, 160E-l50W) and the western Pacific worm pool (5N-5S, 120E-l60E) were analyzed. Among the lagged cross-correlation cycles in NINO regions, the maximum correlations for the negative lagged months prevail in NINO 1+2 and NINO 3, and the cross correlations for the positive lagged months NINO 4. It is noteworthy that correlation between the western Pacific warm pool SSTA and the monsoon rainfall in Korea and South China have the maximum value at negative 4 month lag. The evolution of the correlation between the East Asia monsoon rainfall and SSTA is linked to the equatorial convective cluster and related to northward propagating situation, and raising the possibility that the East Asia monsoon precipitation may be more fundamentally related to the interaction of intraseasonal oscillations and the sub-regional characteristics including the surface boundary conditions and the behavior of climatological air mass.

• 한국환경과학회지
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• 제19권3호
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• pp.295-304
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• 2010

Actual evapotranspiration (AET) in the Suyeong-gu was estimated and correlations between AET and meteorological factors were analyzed. The study area was Suyeong-gu lay at the east longitude $129^{\circ}$ 05' 40" ~ 129$^{\circ}$ 08' 08" and north latitude $35^{\circ}$ 07' 59" ~ $35^{\circ}$ 11' 01". The Kumryun mountain, the Bae mountain, the Suyeong river and the Suyeong bay are located on west, north, northeaster and south side in the study area, respectively. AET was estimated using precipitation (P), potential evapotranspiration (PET) and plant-available water coefficient. Meteorological factors to estimate PET were air temperature, dewpoint temperature, atmospheric pressure, duration of sunshine and mean wind speed (MWS). PET and AET were estimated by a method of Allen et al. (1998) and Zhang et al. (2001), respectively. PET was the highest value (564.45 mm/yr) in 2002 year, while it was the lowest value (449.95 mm/yr) in 2003 year. AET was estimated highest value (554.14 mm/yr) in 2002 year and lowest value (427.91 mm/yr) in 2003 year. Variations of PET and AET were similar. The linear regression function of AET as PET using monthly data was AET=0.87$\times$PET+3.52 and coefficient of determination was high, 0.75. In order to analyze relationship between the evapotranspiration and meteorological factors, correlation analysis using monthly data were accomplished. Correlation coefficient of AET-PET was 0.96 high, but they of AET-P and PET-P were very low. Correlation coefficients of AET-MWS and PET-MWS were 0.67 and 0.73, respectively. Thus, correlation between evapotranspiration and MWS was the highest among meteorological factors in Suyong-gu. This means that meteorological factor to powerfully effect for the variation of evapotranspiration was MWS. The linear regression function of AET as MWS was AET=84.73$\times$MWS+223.05 and coefficient of determination was 0.54. The linear regression function of PET as MWS was PET=83.83$\times$MWS+203.62 and coefficient of determination was 0.45.

• Asian Pacific Journal of Cancer Prevention
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• 제16권10호
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• pp.4339-4345
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• 2015

Occupational exposure to wood dust is one cause of nasopharyngeal cancer (NPC); however, assessing this exposure remains problematic. Therefore, the objective of this study was to develop a semi-quantitative exposure assessment method and then utilize it to evaluate the association between occupational exposure to wood dust and the development of NPC. In addition, variations in risk by histology were examined. A case-control study was conducted with 327 newly diagnosed cases of NPC at the National Cancer Institute and regional cancer centers in Thailand with 1:1 controls matched for age, gender and geographical residence. Occupational information was obtained through personal interviews. The potential probability, frequency and intensity of exposure to wood dust were assessed on a job-by-job basis by experienced experts. Analysis was performed by conditional logistic regression and presented in odds ratio (ORs) estimates and 95% confidence intervals (CI). Overall, a non significant relationship between occupational wood dust exposure and NPC risk for all subjects was observed (ORs=1.61, 95%CI 0.99-2.59); however, the risk became significant when analyses focused on types 2 and 3 of NPC (ORs=1.62, 95%CI 1.03-2.74). The significant association was stronger for those exposed to wood dust for > 10 year (ORs=2.26, 95%CI 1.10-4.63), for those with first-time exposure at age > 25 year (ORs=2.07, 95%CI 1.08-3.94), and for those who had a high cumulative exposure (ORs=2.17, 95%CI 1.03-4.58) when compared with those considered unexposed. In conclusion, wood dust is likely to be associated with an increased risk of type 2 or 3 NPC in the Thai population. The results of this study show that semi-quantitative exposure assessment is suitable for occupational exposure assessment in a case control study and complements the information from self-reporting.

• 산경연구논집
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• 제9권7호
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• pp.53-59
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• 2018

Purpose - This study examines the effect of control-ownership wedge on stock crash risk. In Korea, controlling shareholders have exclusive control rights compared to their cash flow rights. With increasing disparity, controlling shareholders abuse their power and extract private benefits at the expense of the minority shareholders. Managers who are controlling shareholders of the companies tend not to disclose critical information that would prevent them from pursuing private interests. They accumulate negative information in the firm. When the accumulated bad news crosses a tipping point, it will be suddenly released to the market at once, resulting in an abrupt decline in stock prices. We predict that stock price crash likelihood due to information opaqueness increases as the wedge increases. Research design, data, and methodology - 831 KOSPI-listed firm-year observations are from KisValue database from 2005 to 2011. Control-ownership wedge is measured as the ratio (UCO -UCF)/UCO where UCF(UCO) is the ultimate cash-flow(control) rights of the largest controlling shareholder. Dependent variable CRASH is a dummy variable that equals one if the firm has at least 1 crash week during a year, and zero otherwise. Logistic regression is used to examine the relationship between control-ownership wedge and stock price crash risk. Results - Using a sample of KOSPI-listed firms in KisValue database for the period 2005-2011, we find that stock price crash risk increases as the disparity increases. Specifically, we find that the coefficient of WEDGE is significantly positive, supporting our prediction. The result implies that as controlling shareholders' ownership increases, controlling shareholders tend to withhold bad news. Conclusions - Our results show that agency problems arising from the divergence between control rights and cash flow rights increase the opaqueness of accounting information. Eventually, the accumulated bad news is released all at once, leading to stock price crashes. It could be seen that companies with high control-ownership wedge are likely to experience future stock price crashes. Our study is related to a broader literature that examined the effect of the control-ownership wedge on stock markets. Our findings suggest that the disparity is a meaningful predictor for future stock price crash risk. The results are expected to provide useful implications for firms, regulators, and investors.

• 한국콘텐츠학회논문지
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• 제16권4호
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• pp.675-690
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• 2016

본 연구는 중국내 한류 컨텐츠 소비를 설명할 수 있는 이론적 배경을 살펴보고자 한다. 특히, 기존의 연구에서, 한류의 이론적 배경으로 제시 되었던 국제성, 근접성, 현대성이 어떻게 중국내 한류 소비 동기에 영향을 미치고, 결국 한국 TV프로그램 (드라마, 버라이어티 쇼 등) 소비에 영향을 주는지 알아보고자 한다. 연구 결과, 첫째, 국제성 및 근접성은 한류 소비 동기에 긍정적 영향을 미친 반면, 현대성은 부정적 영향을 미쳤다. 즉, 국제적 가치관을 보일수록, 중국과 한국의 근접성이 높다고 생각할수록, 전통적인 가치관을 지닐수록 한류를 소비하고자 하는 동기가 더 크게 나타났다. 둘째, 한류 소비 동기는 실질적인 한국 TV프로그램 소비에 긍정적인 영향을 미치는 것으로 나타났다. 수정된 연구 모델에서, 근접성, 그 다음으로 국제성이 한류 소비 동기에 가장 큰 영향을 끼치는 것으로 드러났다. 이러한 결과는 중국내 한류 현상을 설명하는데 있어서 근접성이 가장 타당한 이론적 접근임을 시사한다. 또한 인구통계학적 변인과 한류 소비 동기의 관계에서, 남성보다는 여성이, 가족 수입이 높을수록, 교육 수준이 낮을수록 한류 소비 동기에 긍정적인 영향을 미치는 것으로 나타났다.