Application of cluster analysis for the hydrogeochemical factors of saline groundwater in Kimje, Korea

김지훈,Byoung-Woo Yum,김락현,고동찬,Tae-Jin Cheong,Jeongho Lee 한국지질과학협의회 2003 Geosciences Journal Vol.7 No.4

Park, Y.S., Kim, J.K. and Kim, J., 201, Petrochemistry of Granitoids322 Ji-Hoon Kim, Byoung-Wo Yum, Rak-Hyeon Kim, Dong-Chan Koh, Tae-Jin Cheong, Jeongho Lee and Ho-Wan Changin the Youngwang-Kimje area, Korea. Economic and Environ-mental Geology, 34, 55-70 (in Korean with English abstract).Price, B.N. and Calvert, S.E., 1977, The contrasting geochemicalbehaviors of iodine and bromine in resent sediments from theNambian Shelf. Geochimica et Cosmochimica Acta, 41, 1769-1775.Richter, B.C., Kreitler, C.W. and Bledsoe, B.E., 1993, Geochemicaltechniques of identifying sources for groundwater salinization.CRC Pres, New York, 285 p.Stumm, W. and Morgan, J.J., 196, Aquatic chemistry: chemicalequilibria and rates in natural waters. 3rd edn. Wiley, New York,1022 p.

상악 4절치의 후방견인시 나타나는 현상에 관한 유한요소법적 분석

천옥진,김태우,서정훈 대한치과교정학회 1995 대한치과교정학회지 Vol.25 No.5

상악치열에서 제 1 소구치를 발거하고, 이 위치로 견치를 후방이동시킨 상태에서 retraction archwire를 사용하여 상악 4절치를 한 묶음으로 후방견인시켰을 때 초기에 나타나는 모든 힘 체계와 개개치아의 이동양상을 살펴보고 바람직하지 않은 치아이동을 감소시키기 위한 방안을 모색하고자 본 연구를 시행하였다. 먼저 유한요소법을 이용하여 상악 치아와 치근막의 해부학적 형태 및 생체적 특성을 컴퓨터로 재현시키고 모형화된 브라켓을 부착시킨 후, beam 요소를 사용하여 5종의 retraction loop를 하나씩 부여한 다섯 가지의 탄선을 모형화하고, 브라켓과 탄선간에는 gap 요소를 사용하여 모형화함으로써 전체 유한요소 모형을 완성하였다. loop의 형태, activation의 양, gable bend와 torque의 조건에 따른 차이를 검토하기 위해, 각 조건을 변화시켜 loop를 activation시켰을 때 탄선이 발휘하는 힘과 모멘트, 치아이동의 변위를 3차원적으로 정량적 및 가시적으로 평가하고 비교, 분석한 결과 다음과 같은 결론을 얻었다. 1. tear-drop loop archwire 사용시 각 치아의 근원심이동 및 설측이동이 발치공간 폐쇄에 도움이 되었으나, 바람직하지 못한 상하이동과 각 방향으로의 회전이동이 부가적으로 나타났다. 2. 다섯 가지의 retraction archwire 중 T-loop archwire에서 공간폐쇄에 도움이 되는 치아이동이 가장 작게 나타났으며, 각 방향으로의 회전이동 역시 가장 작게 나타났다. 3. tear-drop loop archwire에서 activation 양을 증가시킴에 따라 공간폐쇄에 도움이 되는 치아이동이 점차 증가했으나, 바람직하지 못한 상하이동과 각 방향으로의 회전이동이 함께 증가했다. 4. tear-drop loop archwire에서 loop의 전후방에 gable bend 부여시 전치에서 근원심방향의 치체이동에 도움이 되었으나, 모든 치아에서 상하이동과 각 방향으로의 회전이동이 함께 증가했다. 5. tear-drop loop archwire의 절치부에 치근 설측 torgue 부여시 이들 치아의 순설경사를 개선시키는 효과를 얻었으나, 그 반작용으로 견치 치관의 설측회전이 크게 증가했으며, 전치의 상하이동과 모든 치아에서 각 방향으로의 회전이동이 증가했다. This study was designed to investigate force systems and tooth movements produced by retraction archwire during retraction of four maxillary incisors after the maxillary canine retraction into the maxillary first premolar extraction space using the computer-aided three-dimensional finite element method. A three-dimensional finite element model, consisting of 2248 elements and 3194 nodes, was constructed. The model consisted of maxillary teeth and surrounding periodontal membranes, .022˝x.028˝-slot brackets, and 5 type of retraction archwires(.019˝x.025˝stainless steel archwire) modeled using the beam elements. The contact between the wire and the bracket slot was modeled using the gap elements because of the non-linear elastic behaviors of the contact between them. The forces and moments, and displacements produced by retraction archwire were measured at various conditions to investigate the difference according to types of loops, magnitudes of activation force, gable angle, and anterior lingual root torque. The results were expressed quantitative and visual in the three-dimensional method. The following conclusions can be drawn form this study : 1. When the tear-drop loop archwire was activated, the mesio-distal and lingual translational movements of the teeth helped to close the extraction space, but unwanted movements of the teeth including intrusions and extrusions, and rotational movements in each direction occurred. 2. Activation of T-loop archwire compared with those of other types of retraction archwires produced the least translational movements of the teeth helped to space closure and also least unwanted movements of the teeth. 3. Increasing amount of activation in the tear-drop archwire led not only to increase of translational movements of the teeth helped to space closure, but also increase if unwanted movements of the teeth. 4. Addition of gable bend in the tear-drop archwire helped anterior teeth to translational movements in the mesio-distal direction, but increased unwanted movements of the teeth. 5. Addition of anterior lingual torque in the tear-drop archwire helped central and lateral incisor to improve their facio-lingual inclination, but increased unwanted movements of the teeth.

Serratia liquefaciens AL-11이 생산하는 Alkaline Lipase의 특성 및 작용양상

최청,김태완,안봉전,김영활,손준호,김성,최희준 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.1

본 효소의 최적 반응온도는 약 45℃이고, 최적 pH는 10.0 정도였고, pH 7.0~10.0 범위와 30~50℃의 범위에서 안정하였다. 금속이온중 Mn^2+, Ca^2+ 등에 의하여 활성이 증대되었으나 Fe^2+, Pb^2+와 Zn^2+ 등에 의해서는 효소 활성이 저해되었고, 효소활성 저해제 중 ethylenediaminetetraacetic acid(EDTA)에 의해 강한 저해작용을 나타내어 본 효소는 효소분자 중 금속이온이 관여하는 것으로 추정되었다. 효소반응 처리한 olive oil 가수분해물을 박충크로마토그래피 분석한 결과 Serratia liquefaciens AL-11이 생산하는 지방분해효소는 기질특이성이 비특이적이었으며, sodium cholate, sodium edoxychol-ate, sodium taurocholate 등의 담즙산염에 의해 효소활성이 증대되었다. The optimum temperature and pH for the enzyme activity were 45℃ and 10.0, respectively. The enzyme was stable in a pH range of 5 to 10, and 62% of its activity was lost on heat treatment at 60℃ for 20 min. The activity of the purified enzyme was inhibited by Fe^2+, Zm^2+ and Pb^2+, and slightly activated by Mn^2+ and Ca^2+. γ-Chloromercuribenzoic acid, 2,4-dinitrophenol and H_2O_2 did not show inhibitory effect on the lipolytic activity of the alkaline lipase but ethylenediaminetetraacetic acid inhibited the enzyme activity. This suggested that the enzyme have metal group in its active site. Sodium salts of bile acids stimulated the enzyme activity. Analysis of hydrolyzates of olive oil after the lipase reaction revealed that Serratia liquefaciens AL-11 produced non-specific lipolytic enzyme.

경상도 전통 마른 명태 식해의 품질특성

최청,구태호,김성,최희진,성태수 한국식생활문화학회 2002 韓國食生活文化學會誌 Vol.17 No.3

The quality characteristics of traditional Kyungsangdo Myungtae (Alaska pollack) sikhae including optimal composition of the product were investigated. In the sensory evaluation, the Myungtae sikhae made from Gampo accepted to be best for traditional Kyungsangdo Myungtae sikhae and it is called standard sikhae. The standard sikhae was prepared as follows: dried-Myungtae 200g, cooked rice 230g, red pepper 92g, garlic 112g, ginger 100g, radish 1.6kg, salt 20g, and malt meal 65g. The Myungtae sikhae made from Gampo showed higher values in total sugar, free reducing sugar, and nitrogen compounds than the Myungtae sikhae made from another locations. The sugar of standard sikhae consisted of four kinds including glucose. And, the contents of free amino acid was increased in the order of glutamic acid, alanine, and methionine. The composition of free amino acid in Myungatae sikhae contained 17 kinds, and the contents was increased in order of glutamic acid, aspartic acid, and proline. The organic acid of standard Myungtae sikhae consisted of 7 kinds including lactic during fermentation. The contents of citric acid, succinic acid, and lactic acid gradually increased during fermentation, and especially, increasing of lactic acid remarkably increased than the different organic acid.

마른명태 식해의 향기성분과 기능성

최청,구태호,장운빈,최희진,우희섭,손규목 한국식생활문화학회 2002 韓國食生活文化學會誌 Vol.17 No.5

The volatile compounds of Myungtae (Alaska pollack) sikhae obtained by simultaneous steam distillation and extraction(SDE) apparatus were separated by gas chromatography(GC) and gas chromatography mass spectrometry(GC/MS). The totals of 155 volatile flavor components was identified in traditional Kyungsangdo Myungtae (Alaska pollack) sikhae, respectively. α-Zingihirene(11.03%) (E)-di-2-propenyl disulfide(7.95%) β-cironellol(6.02%), methyl allyl disulfide(3.58%), cryptone(3.39%), camphene(3.23%), pentano(3.21%), penadecanal(2.66%) and β-phellandrene(2.06%) were contained as the main compounds of Myungatae shikae. The fraction obtained from sikhae were tested for electron donating ability, angiotensin converting enzyme and xanthine oxidase inhibitory activity. There was no electron donation abilities(SC_50) of hexane and water fraction. On the other hand, the abilities of ethylacetate fraction and butanol fraction showed 310.64 ㎍.mL, 1096.49 ㎍/mL, respectively. Angiotensin converting enzyme inhibitory activities(IC_50) of ethylacetate fraction and butanol fraction were 1.623 mg/mL, 1.303 mg/mL, respectively. Xanthine oxidase inhibitory activities(IC_50) of ethylacetate fraction and butanol fraction were 3.591 mg/mL, 2.803 mg/mL, respectively.

쇼트볼의 형상이 피로수명에 미치는 영향

신용승,정성균,강진식,김태형 서울産業大學校 2000 논문집 Vol.51 No.2

To improve fatigue properties, usually the shot peening process is used in the industrial world. In order to achieve optimum, repeatable and reliable shot peening process, the important shot peening parameters must be controlled. The first item needed to achieve high quality shot peening is to keep shot balls in a good quality. This paper discusses of shape of commonly used shot ball. Also, discussed is shot ball Shape's effect of Fatigue Life.

과일과피로부터 폴리페놀 분리에 따른 생리기능연구

안봉전,이진태,곽재훈,박정미,이진영,박태순,손준호,최청 경산대학교 생명자원개발연구소 2003 생명자원과 산업 Vol.7 No.-

Biological activities and anticarcinogenicity of Korean Pear peel were investigated. Electron donating activity and superoxide dismutase(SOD)-like activity of fraction Ⅱ, Ⅲ were up to 90% and 50-60% at 50ppm, respectively. Inhibitory effects on xanthine oxidase were about 80% at 50ppm, breast adenocarcinoma was about 60% at 2,000 ppm, higher Ⅲ than Ⅱ. Inhibitory effect on prostate adenocarcinoma was about 23% at 500 ppm. In conclusion, Korean Pear peel was expected to use as a functional material.

쇼트피닝가공한 평기어의 최적 피닝강도 탐색에 관한 연구

이동선,이국진,김태형,정성균 한국공작기계학회 2005 한국공작기계학회 춘계학술대회논문집 Vol.2005 No.-

The shot peening process is often used to improve fatigue properties of metal parts. Among them, It is the most use in an auto-component. In order to achieve optimum, repeatable and reliable fatigue enhancement from the shot peening process, the important shot peening parameters must be controlled. In this paper, the optimum peening intensity (Almen intensity) condition is investigated by experiment..The Spur Gear steel was used to investigate shot peening effects. The fatigue life at σ_(a)=1,050 and σ_(a)=1,250MPa first gently increases, then drops gently as peening intensity increases compared with unpeened specimen. Experimental results show that the optimum peening intensity range is 0.391~0.434mmA..So the fatigue strength and fatigue life have been tremendously increased by optimum-peening treatment. However, the fatigue strength and fatigue life have been decreased by over peeing.

Ethyoene Oxide 폭로 근로자의 말초 임파구 자매염색분체 교환에 관한 연구

황천현,박종태,장성훈,김대성,이원진,김청식,김영환 大韓産業醫學會 1998 대한직업환경의학회지 Vol.10 No.4

Operators of hospital sterilizers who use ethylene oxide(EtO) were studied to determine the exposure of EtO level and the frequency of sister chromatid exchanges(SCEs) from June 12 to July 20, 1997. To evaluate SCEs in the peripheral blood cells, we selected 22 workers at the central supply room of 4 university hospitals and 22 unexposed workers at the same hospitals according to match sex, age, and smoking habit and also did questionnaires. The mean air concentrations(8-hr TWA) of EtO at 4 university hospitals were less than 1 ppm. The SCE frequencies in exposed workers to EtO and controls were normally distributed. The SCE frequencies in exposed workers to EtO and controls were 6.42±0.63, 5.86±0.69, respectively and their differences were statistically significant(p=0.0093). But there were no statistically significant differences in smoking, alcohol intake, coffee drinking. Especially smokers who exposed to EtO were increased SCE statistically significant than the exposed group who did not smoke.

실리카흄을 흔입한 고강도 콘크리트 개발

홍창우,김태경,김경진,김성환,김남윤,심도식,이정호,윤청호,백민경,원치문,박제선,이주형,정경일 강원대학교 석재복합신소재제품연구센터 1996 석재연 논문집 Vol.1 No.-

콘크리트 구조물이 대형화됨에 따라 설계단면이 증대되어 상대적으로 많은 경제적 손실을 부담하게 된다. 따라서 단면을 감소시키면서도 소요의 하중에 안전한 구조물을 건설하기 위해서는 우선적으로 구조물 건설에 기초가 되는 고품질, 고내구성의 고강도 콘크리트 개발이 절실히 요구된다 본 연구에서는 일정 시멘트비 및 혼화재 비율하에서 소요의 워커빌리티가 확보되는 고강도 콘크리트를 시간과 온도의 변화에 따라 증기 양생하여, 압축, 인장, 휨강도 뿐만 아니라 파괴특성을 실험적으로 연구하였다. 시료 제작시 시멘트 입자 사이의 공극 및 불연속 영역을 충전하여 고밀도화하기 위한 콘크리트용 혼화재로 시멘트 비표면적이 상당히 작은 초미립 분말인 실리카흄을 이용하였다. 또한 AE감수제 및 고성능 유동화제를 사용하여 혼화재의 첨가에 의하여 발생될 수 있는 워커빌리티의 감소를 방지하였다. 실험결과에 의하면 일정 양생 지속 시간하에서 온도의 증가에 따라 콘크리트의 압축, 인장 및 휨강도가 전반적으로 증가하였다. 동일하게 일정 온도하에서 양생 지속시간이 커짐에 따라 강도들이 증가됨을 알 수 있었다. 따라서 상대적으로 높은 온도와 긴 지속 양생 조건하에서 파괴에 대한 저항력이 크게 나타났다. The compressible, tensible, and flexibleresistance of the high strength concrete is analyzed by the experimentation in the present study. For the test, we cure several samples with the silica fume as a mixture being become dense the spaces between the particle of cement under the variation of both the temperature and the curing-interval. Then, the superplasticizer and the ezcon are also used to satisfy the required workability for construction. The compressible, tensible, and flexible resistances to a stress are increased as increasing the temperature and the time interval for the curing. Therefore it is concluded that the overal fractural and mechanical properties is improved by mixing the silica fume into the cement.