• 한국환경농학회지
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• 제19권1호
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• pp.72-74
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• 2000

우리나라 강우의 산성도 중화에 미치는 $NH_4\;^+$ 및 $Ca^{2+}$ 영향을 평가하기 위하여 '98년 5월부터 10월까지 6개월 동안 수원, 안성 및 태안지역에 내린 강우의 주요 이온들의 함량을 조사한 결과, $[H^+]+[NH_4\;^+]+[Ca^{2+}]$의 역대수값으로 계산되는 이론적 산성도는 측정된 pH값에 비해 각각 7.9, 8.7 및 6.5배 높았다. 또한 빗물의 산성도 중화에는 $NH_4\;^+$가 $Ca^{2+}$ 보다 기여도가 컸으며, 지역별 $Ca^{2+}$의 영향은 수원지역이 안성 및 태안지역에 비해 크게 나타났다.

• 한국토양비료학회지
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• 제33권5호
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• pp.356-360
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• 2000

우리나라 강우의 pH 분포와 산성도 중화에 미치는 $NH_4{^+}$ 및 $Ca^{2+}$ 영향을 평가하기 위하여 1993, 1994, 1995, 1997 및 1998년 각각 5월부터 10월까지 6개월 동안 안성지역에 내린 강우의 주요 이온들의 함량을 조사한 결과, 강우의 산성도 분포는 pH 5.0~5.6의 범위가 가장 많았으며 pH 5.6 이상의 강우는 연차적으로 점차 감소하는 경향이었다. 빗물중 $SO_4{^2-}$와 $NO_3{^-}$의 당량비는 1994년 이후 점차 증가하여 빗물중에 함유된 음이온중 $SO_4{^2-}$가 차지하는 비중이 점차 높아졌다. $[H^+]+[NH_4{^+}]+[Ca^{2+}]$의 역대수 값으로 계산되는 이론적 산성도는 측정된 pH값에 비해 5.0~12.6배 높았고 대기중에 존재하는 알카리 물질들에 의한 빗물의 월별 중화력은 강우량이 많은 7월과 8월에 가장 적었다. 또한 빗물의 산성도 중화에는 $NH_4{^+}$가 $Ca^{2+}$ 보다 기여도가 컸으며, 두 이온에 의한 빗물의 중화는 점차 감소하는 경향을 나타냈다.

• 한국농촌계획학회:학술대회논문집
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• 한국농촌계획학회 1996년도 정기총회 및 춘계 학술논문발표회
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• pp.11-13
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• 1996

• 대한수학회논문집
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• 제13권1호
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• pp.171-179
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• 1998

In this paper, we establish Trotted-Kato type convergence theoren for nonlinear semigroups generated by coaccretive operators in a hyperbolic space.

• 대한가정학회지
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• 제41권10호
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• pp.45-55
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• 2003

This study was performed to find ways to improve the wearing comfort of high school boys' summer uniforms. The subjects were 640 boy students of high schools in Cheongju and Ansung city. The data was collected self-administered questionnaires to measure the actual wearing condition and the wearing satisfaction. Factor analysis, t-test, and F-test were used for data analysis. The results were as fellows: 1) Most students were wearing shirts made of polyester/rayon blended fabrics and pants made of wool/polyester blended fabrics. 2) Most students were wearing round neckline T-shirts or running shirts as underwears of the shirts, and trunks as pants. 3) About a half of respondents had altered their summer uniforms, and main alteration of their uniforms was focused on making their pants narrow. 4) The wearing satisfaction of uniforms were classifies into three factors: aesthetic, moving function, thermal comfort wearing sensation. 5) They evaluated the wearing sensation of school uniforms of shirts and pants with low satisfaction. 6) There were partially significant differences in three factors of the wearing satisfaction according to the uniform's fabrics, the wearing of underwear and the alteration of uniform.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.120.2-120
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• 2003

Agrobacterium vitis is a causal agent of crown-gall disease on grapevine. In Korea, grapevine variety (GeoBong) have severely been infected by the bacteria since stems of the variety were buried in soil for overwintering. Infection ratio over 70-80％ was observed on 7 years old GeoBong grapevine in Ansung and Cheonan. PCR specific primers for A. vitis strains were designed using nucleotide sequences of vir A gene in Ti-Plasmid, pheA gene in chromosomal DNA and a URP-PCR polymorphic band. Three hundred bacterial strains were isolated from the different 80 galls formed on GeoBong grapevine in Cheonan and Ansung of Korea and were screened to identify A. vitis using the three specific PCR primers for Agrobacterium vitis. Twenty-four bacterial strains that are detected by the primers were further confirmed by pathogenicity and biochemical methods. To investigate the genomic diversity of the bacterial strains, twenty primers of 20 mer referred to universal rice primers (URP) were applied for PCR fingerprinting, Of them, URP2R and URP2F primers could effectively be used to detect polymorphism within the bacterial strains.

• 한국농공학회지
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• 제39권2호
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• pp.9-18
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• 1997

Abstract This paper presents a heuristic method for optimal design of water distribution system with multiple sources and potential links. In multiple source pipe network, supply rate at each source node affects the total cost of the system because supply rates are not uniquely determined. The Linear Minimum Cost Flow (LMCF) model may be used to a large scale pipe network with multiple sources to determine supply rate at each source node. In this study the heuristic method based on the LMCF is suggested to determine supply rate at each source node and then to optimize the given layout. The heuristic method in turn perturbs links in the longest path of the network to obtain the supply rates which make the optimal design of the pipe network. Once the best tree network is obtained, the frequency count of reconnecting links by considering link failure is in turn applied to form loop to enhance the reliability of the best tree network. A sample pipe network is employed to test the proposed method. The results show that the proposed method can yield a lower cost design than the LMCF alone and that the proposed method can be efficiently used to design irrigation systems or rural water distribution systems.

• The Korean Journal of Ecology
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• 제18권3호
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• pp.385-395
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• 1995

Species effects on soil nitrogen mineralization and nitrification in the top 15 cm of soil were evaluated using the buried-bag incubation method in three coniferous plantations in the Kwangneung Experimental Forest, Kyonggi Province. The plantations were established on a similar soil in 1927, and included Larix decidua, Pinus strobus, and Thuja occidentalis. Ten soil samples within each plantation were taken during an entire growing season (May 2~Oct. 30, 1994). Mean daily nitrogen mineralization rates during 45-day in situ soil incubations were significantly different among species and incubation dates. Growing season nitrogen mineralization also differed significantly among species and ranged from 47.7 mg N/kg soil for Larix decidua to 21.5 ma N/kg soil for Thuja occidentalis. Growing season nitrification differed significantly among species and comprised from 93% to 100% of the total growing season nitrogen mineralized. We speculated that organic matter contents and quality might control nitrogen mineralization and nitrification in these soils.

• 한국수소및신에너지학회논문집
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• 제8권3호
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• pp.131-135
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• 1997

방향족 니트로 화합물들을 10 % Palladium 촉매 존재 하에서 벤젠 용액에서 45 psi의 압력을 가지고 실온에서 수소첨가 반응시켜서 방향족 아민들을 얻었다. 본 연구에서는 방향족 니트로 화합물로써 nitrobenzene-$d_5$, $^{15}N$-nitrobenzene, 그리고 4'-nitrobenzo-15-crown-5를 이용하여 수소첨가 반응을 통하여 방향족 아민들을 합성하였다. 적외선 흡수 스펙트럼에서 수소첨가 반응으로부터 얻어진 아민에서 특성적인 N-H 신축 진동이 3450과 $3350cm^{-1}$에서 나타났다. 연구결과 수소첨가 촉매 반응에 의하여 방향족 아민 화합물을 제조할 때는 수득률이 양호하고 부 생성물의 생성이 크지 않아 다른 방법으로는 쉽게 제조할 수 없는 방향족 아민 화합물을 상업적으로 제조할 수 있음을 보여주고 있다.

• 한국식생활문화학회지
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• 제35권3호
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• pp.311-322
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• 2020

Recently, there is growing interest in studying the dietary patterns that affect the risk of circulatory system diseases (CSDs). We investigated the relationship between CSDs and dietary patterns through a follow-up study in Korea (2001-2016). The participants of this study were obtained from the Korean Genome and Epidemiology Study (KoGES). This study was a large community-based cohort study (the Ansan-Ansung areas) conducted to assess the effects of various factors, especially diet, on the onset of chronic diseases among the Korean population aged 40-69 yrs. Baseline data were collected from 2001 to 2002, and follow-up studies were performed every 2 yrs, with over 7 follow-up studies performed (2015-2016). Three dietary patterns were identified using factor analysis: "vegetable and seafood (men)/soup and stew (women)" pattern, "sweet foods and breads-rice cake" pattern, and "multigrain rice and cooked white rice" pattern. None of the dietary patterns were significantly associated with the risk of CSDs in either men or women. Our follow-up study is meaningful as it investigated whether the dietary patterns of individuals according to sex affects the development of CSDs.