가축분뇨 해양투기 금지 전후 하천 수질 변동 경향성 분석

최현미 ( Hyeon-mi Choi ),조용철 ( Yong-chul Cho ),이보미 ( Bomi Lee ),류인구 ( In-gu Ryu ),김상훈 ( Sang-hun Kim ),신동석 ( Dongseok Shin ),유순주 ( Soonju Yu ) 한국물환경학회 2021 한국물환경학회지 Vol.37 No.2

Ocean dumping manure was prohibited in Korea until the end of 2012. Undumped manure was treated by resourcification, purification, and public process in a facility. But poor storage of untreated manure and overproduced compost can pollute river water. In this study, linear regression, Mann-Kendall, Seasonal Mann-Kendall, LOWESS trend, and Spearman’s correlation analysis were conducted for investigating the changes in the water quality of Bukhan and Imjin river before and after the prohibition of ocean dumping. In 2017, the Imjin River basin had more than 5 .7 times livestock breeding heads than the Bukhan River basin and more than 3.5 times livestock manure. The areas of land, farmland, and nutrient balance were also higher in the Imjin River basin. Since the two basins have different environments, it is expected that the characteristics of changes in water quality due to the increase in livestock manure generation and treatment methods will be different when comparing the water quality trends before and after the ban. The result of the trend analysis revealed a decrease in EC before the ban but an increase afterward. T-N and BOD of Imjin river increased slightly before the ban but demonstrated great enhancement thereafter. Other sites and T-P exhibited no trend. The correlation analysis result showed that the increase in the number of livestock rearing was correlated with the increase in T-P of Bukhan River and BOD of Imjin River. The increase in livestock manure production was not correlated with the Imjin River basin, while a correlation was observed with the Bukhan River with an increase in T-N and EC and the decrease in T-P.

금합금과 Ni-Cr 합금의 납착부 인장강도

정준호,최현미,최정호,안승근,송광엽,박찬운,Jeong, Jun-Oh,Choi, Hyeon-Mi,Choi, Jeong-Ho,Ahn, Seung-Geun,Song, Kwang-Yeob,Park, Charn-Woon 대한치과보철학회 1996 대한치과보철학회지 Vol.34 No.1

The purpose of this study was to evaluate the tensile strength of solder joint between gold alloy and nickel-chromium alloy. The specimens were made with type III gold alloys and Ni-Cr-Be alloy and Degular Lot 2 solder. Eighteen paired specimens were made, and subdivided into three groups. Group I specimens were gold alloy-gold alloy combination, Group II specimens were gold alloy-Ni-Cr alloy combination, Group III specimens were Ni-Cr alloy-Ni-Cr alloy combination. Solder block were made with solder investment(Degussa A,G, Germany) and stored in room temperature for 24 hours. To reduce the formation of metallic oxide and increase wetting properties, flux was used before preheating and soldering procedure. The specimens were preheated at $650^{\circ}C$ and flux were applied again and gas-oxygen torch was used to solder the specimen. All soldered specimens were subjected to a tensile force in the Instron universal testing machine : the crosshead speed was 1 mm/mim. Tensile strength values of three soldered joint groups were 1. Gold alloy-Gold alloy solder joint : $$48.8kg/mm^2$$ 2. Gold alloy-Ni-Cr alloy solder joint : $$30.9kg/mm^2$$ 3. Ni-Cr alloy-Ni-Cr alloy solder joint : $$31.8kg/mm^2$$ The microscopic examination of fracture site showed cohesive and combination fracture modes in gold alloy specimens, but showed all adhesive fracture modes in Ni-Cr alloy containing specimens.

통계분석 및 수질지수를 이용한 남한강 하류 유역의 수질 평가

조용철 ( Yong-chul Cho ),최현미 ( Hyeon-mi Choi ),류인구 ( In-gu Ryu ),김상훈 ( Sang-hun Kim ),신동석 ( Dongseok Shin ),유순주 ( Soonju Yu ) 한국물환경학회 2021 한국물환경학회지 Vol.37 No.2

Water pollution in the lower reaches of the Namhan River is getting worse due to drought and a decrease in water quantity due to climatic changes and hence is affecting the water quality of Paldang Lake. Accordingly, we have used a water quality index (WQI) and statistical analysis in this study to identify the characteristics of the water quality in the lower reaches of the Namhan River, the main causes of water pollution, and tributaries that need priority management. Typically, 10 items (WT, pH, EC, DO, BOD, COD, SS, T-N, T-P, and TOC) were used as the water quality factors for the statistical analysis, and the matrix of data was set as 324 × 10·1. The correlation analysis demonstrated a strong correlation between Chemical Oxygen Demand (COD) and T-P with a high statistical significance (r=0.700, p<0.01). Furthermore, the result of principal component analysis (PCA) revealed that the main factors affecting the change in water quality were T-P and organic substances introduced into the water by rainfall. Based on the Mann-Kendall test, a statistically significant increase in pH was observed in SH-1, DL, SH-2, CM, and BH, along with an increase in WQI in SH-2 and SM. BH was identified as a tributary that needs priority management in the lower r eaches o f t he N amhan R iver, with a “ Somewhat p oor” ( IV) g rade i n T -P, “Fair” g rade i n WQI, and “Marginal” grade in summer.

김치 분말첨가 식빵의 품질 특성

김래영,기미라,김문용,이군자,최현미,전순실,Kim Rae-Young,Ki Mi-Ra,Kim Mun-Yong,Lee Goon-Ja,Choi Hyeon-Mee,Chun Soon-Sil 동아시아식생활학회 2005 동아시아식생활학회지 Vol.15 No.3

White bread with 1, 2, 3, 4 and $5\%$ Kimchi powder added and control samples were tested for moisture content, volume, height, color, free amino acid content, texture, and sensory characteristics. Moisture content was about $40.46\~41.35\%$ and increased according to the addition of Kimchi powder. Volume and height were increased with increasing Kimchi powder content For the crust and crumb color, lightness was decreased, but yellowness and redness were increased as Kimchi powder content increased For free amino acid content, glutamic acid, alanine, serine and leucine were detected in the white bread, and samples with higher content of kimchi powder showed higher amount of total free amino acid content From the sensory analysis, one with $3\%$ kimchi powder got the highest score for flavor, texture, color, moistness and overall acceptability.

임진강 유역 오염물질 총량관리를 위한 유량-수질 자료의 통계분석

조용철 ( Yong-chul Cho ),최현미 ( Hyeon-mi Choi ),이영준 ( Young Joon Lee ),류인구 ( Ingu Ryu ),이명구 ( Myung-gu Lee ),구동회 ( Donghoi Gu ),최경완 ( Kyungwan Choi ),유순주 ( Soonju Yu ) 한국환경영향평가학회 2018 환경영향평가 Vol.27 No.4

본 연구의 목적은 임진강 수질오염총량관리제도를 위한 단위유역의 2012년 1월부터 2016년 12월까지 유량과 수질자료를 통계분석기법에 이용하여 수질특성을 평가하는 것이다. 유량과 수질은 평균 8일 간격으로 측정하였으며 11개 항목을 상관분석, 주성분 분석, 요인분석, 군집분석에 사용하였다. 군집분석의 결과 공간변화에 따라 자연형 하천, 도시형 하천, 점오염원 영향이 큰 지점 등으로 3개의 그룹으로 분류되었으며, 오염원의 종류와 수질 유사성이 군집 분류에 영향을 미치는 것으로 나타났다. 일원 분산분석과 사후검정을 이용하여 군집간의 평균사이에는 통계적으로 유의한 수준의 차이가 있는 것으로 나타났다. 상관분석에서 COD_Mn와 TOC의 상관계수가 0.951(p<0.01)로 상관성이 통계적으로 유의하게 높게 나타났다. 주성분 분석 결과 3개의 주성분으로 전체 수질특성의 72%를 설명할 수 있으며 요인분석에서 주요 요인은 EC, BOD₅, COD_Mn, TN, TP, TOC 항목으로 나타나 유기물과 영양염류 간접지표가 수질에 영향을 미치는 것으로 나타났다. 본 연구에서 요인점수를 다중 선형회귀분석에 적용하여 회귀 방정식을 제시하고 임진강 유역 수질관리에 유기물 및 영양염류 간접지표 항목의 관리가 중요하다고 판단된다. The purpose of this study was assessment the quality of water by using the statistical analysis technique of the Water flow and water quality from January 2012 to December 2016 at the unit basin for total pollutant load management system (TPLMS) in the Imjin River. Water flow and water quality were monitored at an average of 8 day intervals, 11 parameters were used for correlation analysis, principal component analysis (PCA), factor analysis (FA), and cluster analysis (CA). The Hierarchical CA was classified into three according to the change of space, such as natural rivers, urban rivers, point with large influence of point pollution source, it was found that the type of contamination source the similarity of water quality affected the classification of cluster. Using one-way analysis of variance (ANOVA) and post-hoc Analysis, there were statistically significant differences between mean values among the clusters. Correlation analysis showed the correlation coefficient between COD_Mn and TOC was 0.951 (p<0.01) and the correlation was statistically significantly higher. According to the result PCA and FA, 3 principal components can explaining 72% of the total variations in water quality characteristics and main factor was EC, BOD₅, COD_Mn, TN, TP and TOC indirect indicators of organic matter and nutrients were influenced. This study presented the regression equation obtained by applying the factor scores to the multiple linear regression analysis and concluded that the management Indirect indicators of organic matter and nutrients is important for water quality management in the Imjin River basin.

댐 방류량에 따른 통계학적 수질 평가

조용철 ( Yong-chul Cho ),구동회 ( Donghoi Gu ),최현미 ( Hyeon-mi Choi ),박주혜 ( Ju Hye Park ),박민지 ( Min-ji Park ),이영준 ( Young Joon Lee ),유순주 ( Soon Ju Yu ) 한국물환경학회(구 한국수질보전학회) 2018 한국물환경학회·대한상하수도학회 공동 춘계학술발표회 Vol.2018 No.-

유리단 국소의치 장착 후 M.K.G.에 의한 하악운동 형태 및 속도의 변화

최현미,조주온,이상돈,송광엽,박찬운 全北大學校 齒醫學硏究所 1992 전북치대논문집 Vol.10 No.1

The purpose of this study is to evaluate the effects of distal extension partial denture on the mandibular movement patterns and velocity. The subjects are 10 patients who have unilateral or bilateral distal extension edentulous area in maxillary and/or mandibular arches. Their mandibular movement patterns and velocity had been measured by Mandibular Kinesiograph(M.K.G.-K6 diagnostic system, Myo-tronics Inc. Seattle. WA. U.S.A.) once just before the treatment and 8 times every week since the dentures were placed. The data have been analyzed statistically by means of ANOVA and Tukey test. The results have been obtained as follows : 1. The placement of the dentures has reduced the amount of vertical and antero-posterior displacement in the habitual mandibular movement significantly(p<0.01). 2. The maximum opening and closing velocity and the mean opening and closing velocity showed no significant change with the placement of the partial dentures(p>0.01). 3. The velocity trace of maximum opening-closing movement has been more regularized and well-coordinated, and the number of clicks decreased continuously after placement of the dentures and showed stable patterns since the 5th week(p<0.01). 4. The left deviation has been decreased significantly after the placement of the dentures and showed no significant change since the 4th week. The right deviation has also been reduced, but there was shown no difference after the 1st week(p<0.01). 5. The crossover pattern has been most frequently observed in the frontal plane and the sagittal plane. It has not been changed with the denture placement and stabilized uniformly.

컴프리 葉의 조직배양에서의 植物體 再分化에 미치는 식물호르몬의 영향

車賢哲,崔賢美 단국대학교 1993 論文集 Vol.27 No.-

This study was conducted in order to regenerate plants from leaf explants and callus induced from the leaves of comfry (Symphytum peregrium). Calli were induced from leaf blade on MS medium supplemented with 1.0 mg/l 2,4-D and 1.0~2.0 mg/l kinetin. The shoot formation from leaf explants was initiated on MS medium supplemented with IAA in combination with kinetin. The root was also induced on MS medium supplemented 0.5-1.0 mg/l IAA and 0.1-2.0mg/l kinetin. The organogenesis from callus was formed to roots on B5 medium supplemented with kinetin, BAP, 2iP, irrespective to their kind and quantity Plantlets were regenerated from callus in B5 medium containing kinetin in combination with IAA or Containing BAP in combination with IAA. The optimum concentration of growth regulator for plant regeneration was estimated to be 2.0 mg/l BAP.