Flexural Responses of Prestressed Hybrid Wide Flange Composite Girders

Sun?Jin Han,Deuck Hang Lee,Jae?Yuel Oh,Seung?Ho Choi,Kang Su Kim 한국콘크리트학회 2018 International Journal of Concrete Structures and M Vol.12 No.5

In this study, prestressed hybrid wide flange (PHWF) composite girders were proposed, and full-scale flexural tests were conducted to evaluate their structural performances. This new proposed girder system was developed and designed to effectively resist external loads considering the actual construction sequences. Two specimens with and without shear connectors were fabricated and tested to examine the effect of the shear connectors for achieving the fully-composite behaviors between a cast-in-place (CIP) concrete and the prefabricated prestressed steel–concrete composite girder. The test results showed that sufficient flexural strengths and deformation capacities can be obtained in both types of PHWF composite girders with and without shear connectors. To reflect the actual construction stages of the proposed PHWF composite girder, nonlinear flexural analyses were proposed considering the prestress effect and segmental effect before and after composite with the CIP concrete, respectively. The observed and analysis results of strain behaviors of the PHWF girder specimens were also compared and discussed in detail.

한강둔치에서 재배된 농작물 중의 미중금속 함량에 관한 연구

김연천,전옥경,양혜란,최영희,한선희,이강문,Kim, Youn-Choen,Chun, Ock-Kyoung,Yang, Hae-Ran,Choi, Young-Hee,Han, Sun-Hee,Lee, Kang-Moon 한국식품위생안전성학회 2000 한국식품위생안전성학회지 Vol.15 No.3

한강 고수부지 및 지천인 안양천, 탄천, 중랑천변의 경작지에서 채집된 36종 285건의 농작물에 대한 Pb, Cr, Cd, Fe, Zn, Mn, Cu. Hg의 농도를 측정하고 그 결과를 채집 시기, 채집 지역 및 작물별로 비교, 분석한 결과, 작물 중의 중금속 함량은 평균치를 기준으로 볼 때 Fe(34.592 ppm)>Mn(11.071 ppm)>Zn(8.853 ppm)>Cu(1.795 ppm)>Cr(0.237 ppm)>Pb(0.100 ppm)>Cd(0.011 ppm)>Hg(0.003 ppm) 순으로 곡류 및 두류에서는 Zn의 함량이 Mn보다 높고, 채소류와 과실류에서는 Mn의 함량이 Zn보다 높은 양상을 나타냈다. 또한 각 지역에서 채취한 작물의 미량금속 함량의 경우 Fe은 0.004∼203.083 ppm, Cu은 0.017∼22.727 ppm. Mn은 0.000∼74.373 ppm. Zn은 0.080∼37.166 ppm으로 비교적 고농도로 존재하고 있는 반면 유해중금속류인 Pb은 0.000∼0.654 ppm, Cd은 0.000∼0.270 ppm, Cr은 0.000∼l.229 ppm, Hg은 0.000∼0.037 ppm으로 비교적 미량으로 존재함을 알수 있었다. 대상 농작물을 잎, 줄기, 뿌리, 열매로 분류하여 미량금속 함량을 분석한 결과, 분석 대상 금속의 농도가 잎>줄기>뿌리>열매의 순으로 나타났다. 무등의 뿌리 작물에 있어서 Pb은 잎(0.055 ppm))뿌리(0.035 ppm), Cr은 잎(0.118 ppm))뿌리(0.031 ppm), Cd은 잎(0.004 ppm)1뿌리(0.001 ppm), Hg은 잎(0.004 ppm))뿌리(0.001 ppm)으로 뿌리보다 잎에 많은 것으로 나타났는데 이러한 결과로 보아 뿌리는 금속 이온이 흡수되는 기관일 뿐 축적은 잎에 비해 상대적으로 적게 됨을 알 수 있었다. This study was conducted to determine the content of trace metals in crops cultivated in Han-riverside, Anyang stream, Tan stream, and Jungryang stream. Trace metals (Pb, Cr, Cd, Fe, Zn, Cu, Hg) were detected in 36 crops, 285 samples by Atomic Absorption Spectrophotometer and Mercury Analyzer. The average concentration of trace metals in crop samples was in the order of Fe (34.592 ppm)>Mn (11.071 ppm)$\geq$Zn(8.853 ppm)>Cu(1.795 ppm)>Cr(0.237 ppm)>Pb(0.100 ppm)>Cd(0.011 ppm)>Hg(0.003 ppm). In crop samples, the contents of Fe, Cu, Mn, and Zn, which ranges were 0.004-203.083 ppm, 0.017~22.727 ppm, 0.000~74.373 ppm, 0.080~37.166 ppm, respectively, were relatively higher than those of Pb, Cd, Cr, and Hg, which ranges were 0.000~0.654 ppm, 0.000~0.270 ppm, 0.000~l.229 ppm, 0.000~0.037 ppm, respectively. The concentration of trace metals in crop samples was in the order of leafy vegetables > stem vegetables > root vegetables > fruity vegetables. In the root vegetables, such as radish, the content of Pb was leaf(0.055 ppm)>root(0.035 ppm), that of Cr, leaf (0.118 ppm)>root(0.031 ppm), that of Cd, leaf(0.004 ppm)>root(0.001 ppm), that of Hg, leaf(0.004 ppm)>root(0.001 ppm). As the results, it could be thought that root is the organ which doesn't accumulate the heavy metal ions, but absorb them.

다변량 분석법을 이용한 소양강댐 상류 유역의 하천 수질 평가

최한규,백효선,허준영 江原大學校 産業技術硏究所 2002 産業技術硏究 Vol.22 No.A

The object of this study is to evaluate the factors affecting the water quality and to propose the influence of dominant factor quantitatively. The correlation analysis was performed to know the correlationship among the water quality items. As a result of partial correlation analysis, it was shown that the water quality items are affected by the rainfall item directly. The factor analysis was performed to grasp some number of factors on each point for deducing the items of similar variable characteristics. The four points were divided into different factor groups. It was grasped that NH_3-N and NO_3-N items have different variable characteristics after comparing the items. The Multiple regression analysis can decrease the number of observation. In the deduced multiple regression formula, it was shown that the rate of T-N, NH_3-N and NO_3-N in the independent variable took about 60% among all the regression formulas.

하천설계기준의 만곡부 수면형 결정 방법에 대한 적용성 검증

최한규,채홍기,백효선 강원대학교 산업기술연구소 2006 産業技術硏究 Vol.26 No.B

Through the result of calculating the deviation between the value calculated from two-dimensional number formula, one-dimensional number interpretation, and curving part water surface type calculation method, we could confirmed that the deviation is reduced more than 50% when we use curving part water surface type calculation method. Also it was confirmed that there occurs the reduction since the reduction rate of safe room height was 20% in 500 CMS of flood water quantity when we planed the construction of levee by curving part water surface type calculation method. And therefore, we have confirmed that the curving water surface type calculation method can be used as a simple formula in rivers with water quantity less than 500 CMS that flows in and out in less than 90 degree angle.

昭陽湖 上流流城의 降雨强度에 따른 浮游物質流出持性

최한규,유상모,백효선 강원대학교 산업기술연구소 2005 産業技術硏究 Vol.25 No.B

When it is raining or snowing, floating debris flows into a lake and raises its turbidity. High level of turbidity in the lake often causes eutrophication, which pollutes the water. In order to collect and present some essential information for effective management plan for water quality, we carried out our research at the watershed of Mandae-cheon located at the upstream of Soyang Lake. We examined water quality at the time of rainfall or snowfall to analyze the changes in the amount of suspend soils(SS) in the lake.

후두 및 하인두 암종에서 p53단백 발현과 Espstein-Barr Virus 검출

최영환,도남용,나한조,이도용,노용훈,김완수,최종선 조선대학교 2001 The Medical Journal of Chosun University Vol.26 No.2

Background and Objectives : When p53 cancer suppressor gene, occurs gene deletion or point mutation, malignancy develops by loss of p53 function with abnormal p53 protein. The Epstein-Barr virus (EBV) is the causative agent of certain type of lymphoma and undifferentiated nasopharyngeal carcinoma. However, the role of EBV as a causative factor in other head &eck tumors is not fully elucidated except nasopharyngeal carcinoma. This study, the author examined that p53 expression and detection rate of EBV correlate to development of laryngeal and hypopharyngeal squamous cell carcinoma(SCC) and play the possible role of prognostic indicators. Materials and Methods : Formalin-fixed, paraffin-embedded tissue specimen from 32 cases of larynx and hypopharyngeal squamous cell carcinomas were studied by immunohistochemical staining for p53 and EBV. The results of analysis were compared with clinicopathological parameters. Results : p53 expression was 56.3% (18 cases) and the detection rate of EBV was 43.6% (14 cases) of 32 cases in laryngeal and hypopharyngeal squamous cell carcinomas. p53 expression was correlate with histologic grade (p<05) only. Detection of EBV was not correlate with clinicopathological parmeters. Conclusion : These results suggest p53 expression and the detection of EBV may be related with development of laryngeal and hypopharyngeal squamous cell carcinoma. And, the expression of p53 protein can be used as a prognosticator in laryngeal and hypopharyngeal squamous cell carcinoma under certain limitation.

분수로 분류부 형상에 따른 유량분배율 특성의 실험적 연구

최한규,백효선,이석환 江原大學校 産業技術硏究所 2002 産業技術硏究 Vol.22 No.A

The divided channel is not often used on the river and when the installation is for the controlling of the flow quantity. The determination of the channel size is not a easy task. Model tests are examined to confirm the variation of distribution rate by the method of the channel installation and the position of the structure and the adjustment of numerical simulation is executed by the comparing of the results. This study is to execute numerical model according to installation of divided channel by using AQUADYN program, the 2nd dimension numerical model, and HEC-RAS program, the 1st dimension numerical model, by the shape of divided channel. Also, it compares with difference by method about each case.

肺吸蟲症 診斷에 있어서 ELISA법의 應用에 관한 硏究

崔銑吉,李駿商,林漢鍾 고려대학교 의과대학 1984 고려대 의대 잡지 Vol.21 No.1

Human paragonimiasis is one of the common trematode diseases and of very important public health problem in Korea. Although many techniques have been deviced for immunological diagnosis of paragonimiasis, they exhibit low sensitivity and specificity. In this study the enzyme-iinked immununosorvent assay (ELISA) was employed in the diagnosis of human paragonimiasis using Paragonimus VBS(veronal buffered saline) antigen, peroxidase conjugated anti-human Ig G and ortho-phenylenediamine as a substrate by micromethod according to technique of Voller et al. (1979) and McLaren et aI. (1978) with minor modifications. Sera tested were categorized into 106 paragonimiasis, 20 clonorchiasis, 12 taeniasis, 10 toxoplasmosis, 10 hymenolepiasis and 10 non-infected human cases. The results obtained are as follows: 1. In the preliminary study optimal dilutions of conjugate, stock antigen and serum were 1/5,000, 1/400 and 1/400 respectively. 2. The O.D. (optical density) values of the ELISA in the sera of paragonimiasis cases using stock antigen and VBS antigen were 1.291±0.731 and 1.466±0.813, respectively, and the mean O.D. values in the sera of paragonimiasis cases using VBS antigen were not significantly different from that of stock antigen in sensitivity. (p<0.001) Results showed a standard sensitivity in the application of the ELISA in the diagnosis of human paragonimiasis using VBS antigen. 3. The mean O.D. values of the ELISA in 106 sera of paragonimiasis cases were 1.243±0.863 and those of other parasite infection groups and non-infected human group were 0.487±0.549 in clonorchiasis, 0.513±0.521 in taeniasis, 0.158±0.235 in hymenolepiasis, 0.222±0.235 in non-infected human group and that in paragonimiasis was significantly higher than those of other groups. 4. Distribution of the O.D. values of the ELISA, 86 (81.1%) out of 106 paragonimiasis sera, 3 out of 52 other parasite infection group sera and none out of 10 non-infected human group showed highter than that of the positive serum of 1.000 at 488nm) O.D. value. In conclusion, results of this study suggest that the ELISA is more applicable and reproducible in the diagnosis of human paragonimiasis than other immunological tests used especially in seroepidemiological study.

저압 증발형 압력 용기의 응력 변화 특성에 관한 연구

최석천,이용훈,전유신,허선철,정효민,정한식 경상대학교 해양산업연구소 2002 해양산업연구소보 Vol.15 No.-

The purpose of this research is to obtain the characteristics of strain and stress in the vacuum pressure vessel. The vacuum pressure vessel is used to many of industrial devices and cooling tower system. The vessel is under the vacuum pressure in this research, and we analyzed the stress on the vessel surface. As the experimental set up, we introduced the Static Strain Measurement(UCAM 70A, Kyowa) system. The environmental condition of vessel is reserved under vacuum pressure 50mmHg, and the vacuum pressure was made by a ejector pump system.

하천폭의 국부적 축소 및 확대에 따른 수리특성 연구

최한규,김주석,백효선 江原大學校 産業技術硏究所 2007 産業技術硏究 Vol.27 No.B

This research investigated the way of generating the flowing of water in case of artificial fluctuation of river width by the unidimensional numerical analysis in order to reconstruct vertical and expanse features of flowing, and the problem of existing numerical analysis in accordance with local enlargement and reduction of river through hydraulic model experiments with results of numerical analysis. The result revealed that when the local section change in the same river is exist, it showed 0.93m in the case of no change of local section in the hydraulic model experiments and numerical analysis, however, it presented 1.645m on the occasion of local section changes in the hydraulic model experiments and numerical analysis, In other words, there was a significant difference in the existing numerical analysis, when there was a local section change. As a result of the experimental section for the enlargement and reduction of local river width, due to the sensitive change for fluctuation of flood discharge, there was a significant difference between numerical analysis and hydraulic model experiments. In addition, the result of comparison between the enlargement and reduction of local river width confirmed that the result of numerical analysis with hydraulic model experiments showed larger generation of deviation in case of enlargement of section than in case of reduction of section.