Top-Down 공법이 적용된 지중연속벽의 설계시 측방토압의 적합성 평가

홍원표(Hong Won-Pyo),강철중(Kang Chul-Joong),윤중만(Yun Jung-Mann) 한국토목섬유학회 2012 한국지반신소재학회 논문집 Vol.11 No.1

본 연구에서는 지중연속벽 설계시 사용되는 범용 해석프로그램에 Rankin(1857)의 이론토압과 홍원표와 윤중만(1995a)의 경험 토압을 각각 적용하여 Top-Down 공법에 적용된 지중연속벽의 수평변위를 분석하였다. 그리고 이들 해석 프로그램에서 산정된 예측변위량과 지중경사계로 측정된 실측변위량을 비교 검토하였다. 현재 지중연속벽 설계에 적용되는 해석프로그램에는 Rankine의 토압이 주로 적용되고 있다. 검토결과, 지중연속벽의 예측수평변위는 적용되는 토압에 따라 상당히 큰 차이를 나타내고 있다. Rankine의 토압을 적용하여 산정된 예측수평변위 형상은 실측결과와 큰 차이를 보이고 있으며 벽체의 하부에서 예측치가 실측치보다 과다하게 산정되었다. 반면, 홍원표·윤중만의 토압을 적용하여 얻은 예측수평변위 형상과 최대수평변위 량은 실측결과와 유사하게 나타났다. 따라서 Top-Down 공법이 적용된 지중연속벽의 설계시 Rankine의 토압보다는 홍원표·윤중만의 경험토압을 적용하는 것이 적합함을 알 수 있다. The Rankine(1857)'s earth pressure and the Hong and Yun(1995a)'s earth pressure was applied to analyze the lateral displacement of diaphragm wall applied to the Top-Down construction method using the computer program, which is a common design program for diaphragm wall. The lateral displacement estimated by the computer program was compared with the lateral displacement measured by inclinometer. The Rankine's earth pressure has been widely used to design the diaphragm wall in the analysis of computer program. As the result of comparison, the lateral displacement of diaphragm wall was predicted differently according to the applied earth pressures. The behavior of lateral displacement predicted by the Rankine's earth pressure was different with displacement measured by inclinometer and the lateral displacement at the bottom part was overestimated. However, the lateral displacement predicted by the Hong and Yun's earth pressure is similar to the behavior and maximum value of real displacement. Therefore, the Hong and Yun's earth pressure is more suitable than the Rankine' earth pressure to design the diaphragm walls applied to the Top-Down Construction Method.

논문 : Top-Down 공법이 적용된 흙막이벽의 역해석을 이용한 거동분석

홍원표 ( Won Pyo Hong ),강철중 ( Chul Joong Kang ),윤중만 ( Jung Mann Yun ) 대한지질공학회 2012 지질공학 Vol.22 No.1

본 연구에서는 흙막이벽 설계시 널리 사용되고 있는 SUNEX 프로그램을 이용하여 Top-Down 공법이 적용된 지중연 속벽, 주열식 흙막이벽 (CIP벽, SCW벽)의 변형거동을 분석하였다. 해석프로그램에 Rankine의 토압(l857), Terzaghi and Peck의 토압(1967), Tschebotarioff의 토압(1973), 홍원표·윤중만의 토압(1995a)을 적용하여 흙막이벽의 수평변위를 예측하였다. 프로그램 해석결과, 흙막이벽의 수평변위량은 토압의 종류에 따라 큰 차이를 나타내고 있다. 홍원표·윤중만의 토압(I995a)을 적용하여 얻은 흙막이벽의 예측수평변위량이 실측수평변위량과 가장 유사하게 나타났다. 따라서 프로 그램 해석시 홍원표·윤중만의 경험토압(l995a)을 적용하면, Top-Down 공법이 적용된 흙막이벽의 변형거동을 비교적 정확히 예측할 수 있다. Abstract: The behaviors of a diaphragm wall and a contiguous pile wall such as CIP (Case-in-place pile) and SCW (Soil-cement wall), applied to the top-down construction method, were analyzed using the SUNEX program, which is widely used to design earth retaining walls. Four types of earth pressures, as described by Rankine (1857), Terzaghi and Peck (1967), Tchbotarioff (1973), and Hong and Yun (1995a), were applied to the analysis program to predict the lateral displacement of walls, The results show that the displacements of an earth retaining walls vary with the applied earth pressure. The predicted lateral displacement based on Hong & Yun`s (1995a) earth pressure is similar to the measured displacement. Therefore, the actual lateral displacement of an earth retaining wall, as applied to top-down construction method, can be accurately predicted by using an analysis program considering Hong and Yun`s (1995a) earth pressure.

Quinlolone 유도체 국소도포에 의한 좌창치료의 임상적 연구

권철욱,노영석,김재홍,조소연,강형철,함정희 大韓臨床藥理學會 1994 臨床藥理學會誌 Vol.2 No.2

마비형 뇌성마비환자의 뇌파 및 임상양상

윤여훈,송홍기,김형철,이병철,이숙자 대한신경과학회 1996 대한신경과학회지 Vol.14 No.1

미스트 분무 및 스프링클러 관수가 단동 플라스틱 하우스에 미치는 냉각효과

강정윤,최동호,임홍성,허종철 제주대학교 산업기술연구소 2000 尖端技術硏究所論文集 Vol.11 No.2

As crops recently can be cultivated all the year in greenhouses, we need to improve the environment in which crops are able to grow in the summer. Therefore, in this study, we quantitatively got the cooling effects of 4 single span plastic greenhouses in the following ways : by spraying mist or sprinkler, or by opening the side window. and with those variables, we simultaneously did experiments at 4 greenhouses under equivalent conditions to reduce the temperature of the greenhouses in the summer. The results of the experiments are as following : 1) The temperatures of the greenhouses were effectively reduced by both spraying mist and sprinkler. 2) When the mist is intermittently sprayed. the indoor temperature has decreased by 4 degrees centigrade, meanwhile, in the greenhouse to make experiments using sprinkler, the temperature of that has been reduced by 2 degrees centigrade. Therefore, we can see the cooling effects of smaller mist in size as more effective than those of sprinkler. 3) When the greenhouse is naturally ventilated by opening the side window, we have to apply another cooling system because the indoor temperature is higher than the outdoor one.

사업장 근로자의 건강위험 평가도구 개발

홍윤철,임현술,하은희,정규철,조희숙,박혜숙,이용애 大韓産業醫學會 1998 대한직업환경의학회지 Vol.10 No.4

Health Risk Appraisal(HRA) is usually defined as a process by which we expect of individual's chances of death or acquiring specific diseases within a defined period of time. The concept of worksite as an area of health maintenance and promotion is newly developing. Our movement for health promotion of employees has been increasingly known in the worksite. The aim of this study is to develop health risk appraisal tools about health promotion at the worksite for employees. We performed this study by two steps; one step was to develop a HRA questionnaire of worksites in Korea, another was to evaluate the reliability of the questionnaire. For developing HRA questionnaire, we reviewed scientific examples at first, and then weighted the score by delphi. To evaluate the reliability of developed questionnaire, we carried out survey by test-retest method. A total of 131 employees completed HRA questionnaire on two times. The results are as follows. The total score of health risk in unhealthy workers was higher than that of healthy workers. The range of test-retest reliability of responses to the questionnaire was 0.57-0.94. Therefore it seems that this questionnaire was very suitable to assess the health behavior of workers. In conclusion, the developed HRA questionnaire can be used as a tool for evaluating health behavior and for providing health counseling materials.

고속액체크로마토그래피-가시선/자외선 검출기를 이용한 Di(2-ethylhexyl)phthalate 검출 방법 검증과 일부 한국 성인 남성 혈액 중 DEHP 정량

양윤정,명순철,김세철,홍연표 大韓産業醫學會 2005 대한직업환경의학회지 Vol.17 No.1

목적: 이 연구는 HPLC-UV를 이용한 생체 시료 중 저농도의 DEHP 분석법을 CDER 기준에 따라 검증하고 검증된 분석법으로 일부 한국의 혈장 중의 DEHP를 분석하여 인체 노출 정도를 뒷받침할 수 있는 기초 자료를 제시하고자 한다. 방법: 혈액 내 DEHP 정량을 위한 HPLC-UV 정량 분석법을 CDER의 검증 기준인 검량선 및 직선성과 정밀성, 정확성에 대해 시행하였다. 검증된 분석법으로 울산과 춘천 일부 지역의 근로자 30세 이상 60세 이하의 건강한 남성 255명으로부터 채취한 혈액 내 DEHP를 정량하였다. 결과: 혈액 중 DEHP 정량을 위해 사용된 HPLC-UV는 표준액 0∼150 μg/l 에서 직선성을 나타냈다(r²=0.999). 검량한계는 5.22 μg/l , 정량한계는 15.81 μg/l 이었다. 정밀성과 정확도는 2.5 μg/l DEHP 농도에서 첫째 날을 제외하고는 둘째 날과 셋째 날은 CDER 기준에 적합하였다. 50 μg/l 과 150 μg/l DEHP 농도는 모두 CDER 기준에 적합하였다. 대상자의 98 %가 10 μg/l 이하이었고, 85%는 5 μg/l 이하이었고 왼쪽으로 치우친 분포를 나타냈으며, 최고 농도는 18.9 μg/l 이었다. 대상자의 혈액의 DEHP 농도의 기하평균과 기하표준편차는 0.4±1.5 μg/l 이었다. 결론: 본 연구에 사용된 HPLC-UV를 이용한 혈액 중 DEHP 분석법은 CDER 기준에 따라 검증한 결과 정밀도, 정확도, 검출한계 및 정량한계 등 모든 항목에서 기준에 적합하였다. 일부 한국 성인 남자의 혈액 중 DEHP 농도는 0∼18.9 μg/l 이었으며 왼쪽으로 치우친 분포를 나타냈다. Objectives: This study was conducted to validate a simple, rapid and sensitive reverse-phase high-performance liquid chromatographic method with UV detector (HPLC-UV) and present the plasma level of di(2-ethylhexyl)phthalate (DEHP) in some Korean male workers. Methods: HPLC-UV for quantification of plasma DEHP was validated by the following guideline from the Center for Drug Evaluation and Research (CDER) - calibration/standard curve, precision, accuracy and recovery. Plasma DEHP from 255 healthy Korean male workers aged from 30 to 60 years was analyzed by validated HPLC-UV method. Results: The calibration curve over the range 0∼150 μg/l for the plasma DEHP standard solution showed linearity(r²=0.999). The limit of detection (LOD) and limit of quantification (LOQ) of plasma DEHP were 5.22 μg/l and 15.81 μg/l , respectively. The accuracy and precision for 2.5 μg/l of DEHP were acceptable in CDER guideline on the second and third day but not first day, and those for 50 μg/l and 150 μg/l of DEHP were acceptable on all three days(Ed-confirm this addition). The distribution of plasma DEHP level was skewed to the left and ranged from 0 to 18.9 μg/l. The plasma DEHP level was lower than 10 μg/l for 98 % of subjects and lower than 5 μg/l for 85 %. The geometric mean and standard deviation of plasma DEHP were 0.4±1.5 μg/l. Conclusions: The HPLC-UV method for quantification of plasma DEHP was acceptable by CDER guideline. The plasma DEHP of 255 Korean male workers ranged from 0 to 18.9 μg/l and the distribution was skewed to the left.

고지방식이가 백서 골격근 및 지방조직의 지방분해에 미치는 영향

김철희,정윤이,이성진,박중열,홍성관,김홍규,서교일,이기업 대한당뇨병학회 2002 Diabetes and Metabolism Journal Vol.24 No.6

연구배경:지방산화의 증가가 골격근에서 인슐린 저항성을 유발한다는 주장이 꾸준히 제기되어 나왔으나, 최근 제2형 당뇨병 환자나 인슐린저항성 상태에서 골격근의 지방산화능이 저하되어 있다는 보고도 있어 논란이 있는 상태이다. 본 연구에서는 고지방식이를 투여하여 인슐린저항성을 유발한 백서에서 microdialysis 기법을 이용하여 조직내의 지방분해 결과로 간질액내로 방출되는 글리세롤 농도를 골격근 및 지방조직에서 직접 측정하여 지방분해의 변화를 알아보고자 하였다. 방법:정상 Sprague­Dawley 백서를 두 군으로 나누어 4주간 고지방식이 및 저지방식이를 투여하였다. 4주간 기저상태 및 고인슐린 정상혈당 클램프 중의 골격근 및 지방조직에 microdialysis probe를 삽입하고 일정한 농도의 글리세롤을 포함하는 dialysate를 통과시켜 주입액과 유출액의 글리세롤 농도 차이로부터 조직 간질의 글리세롤 농도를 산출하엿다. 결과:기저상태에서 골격근 및 지방조직 간질의 글리세롤 농도는 저지방식이군에 비하여 고지방식이군에서 유의하게 낮았다. 고인슐린 정상혈당 클램프 중에는 골격근 및 지방조직 간질의 글리세롤 농도가 양군에서 모두 억제되었는데, 기저 상태와 마찬가지로 골격근 및 지방조직 모두에서 저지방식이군보다 고지방식이 군에서 더 낮았다. 기저 상태에 대한 고인슐린 클램프중의 글리세롤 방출 억제 정도는 저지방식이군에 비하여 고지방식이군에서 덜 억제되는 경향을 보였는데, 골격근조직에서만 통계적으로 유의하였다. 결론:본 연구 결과는 고지방식이에 의한 인슐린저항성 모델에서 골격근 및 지방조직내 지방분해가 억제되어 있음을 보여주며, 기존의 포도당­지방산 cycle 이론과는 달리 조직내 지방산화의 증가보다는 지방산화능의 감소에 따른 세포내 지방축척이 인슐린저항성과 관련될 가능성을 시사하였다. Background : It has been hypothesized that increased fat oxidation reduces glucose utilization in skeletal muscle, and is responsible for the insulin resistance associated with obesity or high-fat feeding. In contrast, there have been reports that fat oxidation capacity was decreased in skeletal muscles from insulin resistant subjects. This study was undertaken to examine whether insulin resistance in high-fat fed rats is associated with increased lipolysis in skeletal muscle and adipose tissue. Methods : Two groups of Sprague-Dawley rats were fed either high-fat or low-fat diets for 4 weeks. Lipolysis in skeletal muscle and adipose tissue was determined by measurement of interstitial 1 glycerol concentrations by a microdialysis method in basal and hyperinsuline mic-euglycemic clamp conditions. Results : In basal state, plasma glycerol levels and interstitial glycerol concentrations of skeletal muscle, and adipose tissue were lower in high-fat fed than in low-fat fed rats. The degree of suppression of glycerol release by the hyperinsuline mia was smaller in the high-fat diet than in the low-fat diet group. However, plasma and interstitial glycerol concentrations during the hyperinsuline mic euglycemic clamps were also lower in the high-fat diet group. Conclusion : Lipolysis was decreased in skeletal muscle and adipose tissue of insulin resistant, high-fat fed rats. These results support the idea that limited fat oxidation capacity resulting in lipid accumulation in tissues, rather than increased fat oxidation perse, is responsible for the insulin resistance associated with high-fat feeding (J Kor Diabetes Asso 24:641~651, 2000).

延伸 및 熱處理한 Nylon6 纖維의 二重 熔融現象에 對한 實驗的 考察

朴然欽,洪喆載,曺元鎬 成均館大學校 科學技術硏究所 1983 論文集 Vol.34 No.2

The thermal analysis of nylon 6 drawn and heat-treated at different draw ratios and temperatures has been carried out using a differential thermal calorimeter(DSC). The origin of double melting peaks in DSC thermogram has been controversial. If double melting peaks were due to the same species, i.e. the recrystallization process, it is expected that the heat of fusion of lower melting peak increases with the drawing temperature. The opposite, in fact, is observed, i.e., higher drawing temperature results in more of the higher melting peak. A single melting peak of the remelting thermograms shows that double melting peaks in drawn nylon 6 are not caused by the original crystal melting and its recrystallization in DSC. It is concluded that the material which shows the higher melting peak of double melting peaks may be morphologically different from that of the lower melting peak.

승모판 대치술후에 발생한 좌심실유출로 폐색 1예

김도연,조홍근,정익모,박시훈,박성훈,신길자,정병철 대한순환기학회 1998 Korean Circulation Journal Vol.28 No.1