Arch교의 橫桁連結部 局部應力과 疲勞擧動에 관한 硏究

최광순,조호근,손영호,최광규 東亞大學校 建設技術硏究所 1997 硏究論文集 Vol.21 No.2

In this paper, the relation between the local stress and the fatigue behavior at gusset plate connected with main girder and floor beam in arch bridges was obtained. The conclusion was as follows : (1) In-plane bending moment and out-of-plane bending moment are higher than other internal stress resultants. (2) When a vehicle crosses the bridges, the change of out-of-plane bending moment corresponds with the change of relative difference in displacement in the longitudinal direction between the tie-girder and stringer. (3) The change of in-plane bending moment corresponds with the change of the displacement in the transverse direction of arch-rib. (4) Fatigue crack can be initiated by in-plane bending stress that is produced by out-of-plane bending moment at the toe of gusset plate. (5) Fatigue crack can be initiated by tension stress that is produced by in-plane bending moment at the toe of gusset plate.

주개 이온을 첨가한 강유전체 Bi₄Ti₃O_12(BIT) 박막의 특성

최은경,박문흠,김두회,구영건,김상수 昌原大學校 基礎科學硏究所 2001 基礎科學硏究所論文集 Vol.13 No.-

Bismuth layered structure ferroelectric thin films, BIT and donor (V, Nb and W) doped BIT, were prepared on the Pt/Ti/SiO2/Si substrates by sol-gel method. BIT film was characterized by strong c-axis prepared orientation. In the case of donor doped BIT thin films, the degree of c-axis prepared orientation decreased systematically V-BIT→W-BIT→Nb-BIT and Nb-BIT film was shown random orientation. Surface morphologies of BIT and V-BIT films had a plate-like and Nb-BIT and W-BIT had a mixture of plate-like and rod-like. In the results of ferroelectric hysteresis loops, the remanent polarization (2Pr) of random-oriented Nb-BIT capacitor was 26 μC/cm2, and this value was over two times higher than that of 12 μC/cm2 for BIT capacitor. The polarization fatigue up to 4.5×1010 read/write switching cycles of W-BIT capacitor was shown superior to the other capacitors. The polarization of the W-BIT capacitor decreased only 10% of the initial value after 4.5×1010 switching cycles.

경쟁적 효소면역검사를 이용한 혈청내 매독균 항체 검사의 유용성

최하영,박건,장숙진,박영진,문대수 조선대학교 부설 의학연구소 2000 The Medical Journal of Chosun University Vol.25 No.1

Background : Laboratory methods for detection of syphilis are Venereal Disease Research Laboratory (VDRL) and rapid plasma reagin (RPR) test to non-treponemal tests, and fluorescent treponemal antibody absorption (FTA-ABS) and microhemagglutination assay for antibodies to Treponema pallidum (MHA-TP) to treponemal tests. However, RPR card test had many false positive results and FTA-ABS IgM method required high degrees of technical ability and experience. Recently, enzyme immunoassay (EIA) kits for IgM and IgG antibodies to T. pallidum in syphilis have been developed. So, we evaluated that usefulness of competitive EIA for detection of T. pallidum antibody in serum. Methods : RPR positive 38 specimens and negative 6 specimens were compared by T. pallidum hemagglutination (TPHA), two commercial competitive EIA kits for detection of syphilis and FTA-ABS IgM. Those data were compared with concordant and discordant rate of each RPR, TPHA, EIA and FTA-ABS IgM. Results : 28 of 34 RPR positive specimens were TPHA(+) and EIA (+), and 6 of 6 RPR negative specimens were TPHA (-) and EIA (-). The data of two EIAs were same results with TPHA. 3 of 28 EIA positive specimens were FTA-ABS IgM (+), and 16 of 16 EIA negative specimens were FTA-ABS IgM (-). Conclusion: Two commercial competitive EIA kits for detection of syphilis were evaluated. The EIA method could be replaced with RPR and TPHA, and this method was possible to combination for detection of syphilis.

Arch교의 橫桁連結部 局部應力과 疲勞擧動에 관한 硏究

최광순,조호근,손영호,최광규 동아대학교 건설기술연구소 1997 硏究報告 Vol.21 No.2

In this paper, the relation between the local stress and the fatigue behavior at gusset plate connected with main girder and floor beam in arch bridges was obtained. The conclusion was as follows : (1) In-plane bending moment and out-of-plane bending moment are higher than other internal stress resultants. (2) When a vehicle crosses the bridges, the change of out-of-plane bending moment corresponds with the change of relative difference in displacement in the longitudinal direction between the tie-girder and stringer. (3) The change of in-plane bending moment corresponds with the change of the displacement in the transverse direction of arch-rib. (4) Fatigue crack can be initiated by in-plane bending stress that Is produced by out-of-plane bending moment at the toe of gusset plate. (5) Fatigue crack can be initiated by tension stress that is produced by in-plane bending moment at the toe of gusset plate.

흰쥐 십이지장 점막의 Polyamine 대사, [^(14)C]Spermine 단백 결합능 및 [³H]Thymidine DNA 섭취에 대한 Calcitriol과 Prednisolone의 상호작용

최상현,이영재,정휘정,김형건,신경호,천연숙,전보권 고려대학교 의과대학 1997 고려대 의대 잡지 Vol.34 No.1

Calcitriol has been shown to induce the duodenal synthesis of the spermine-binding protein. and hydrocortisone was reported to increase the intestinal polyamine contents. This study examined whether prednisolone might enhance or reduce the calcitriol effects on the polyamine contents, [^(14)C]spermine-protein binding activity, and [^(3)H] thymidine DNA synthesis of the rat duodenum. The mucosal contents of putrescine. spermidine. and spermine were increased by 198.8%, 84.0%, and 78.3%, respectively, within 6 hours after calcitriol. 5 ㎍/kg (CT) and fell down to the control values at 12 hours. And prednisolone. 10 mg/kg (PD) also increased the polyamine contents in similar patterns. They did not counteract each other in the polyamine metabolism. CT increased the [^(14)C]spermine-binding activity of the cytosol protein fraction from the duodenal mucosa by 71.1%. But PD increased the binding activity by 28.0% and did not affect the CT-induced increase. CT increased the [^(3)H]thymidine DNA synthesis of the duodenal mucosa by 42.3%. but PD reduced it slightly. The CT-dependent increase of the synthesis was significantly inhibited by PD. These results suggested that the inhibitory effect of glucocorticoids on the vitamin D dependent increases of the duodenal calcium absorption and mucosal proliferation seems not to be associated with the metabolic changes of polyamines in the duodenal mucosa.

오렌지 껍질로부터 분리된 프라보노이드의 화학요법 감작효과

최철익,변익건,차윤정,김선필,민영돈,유진철,송재경 조선대학교 2001 The Medical Journal of Chosun University Vol.26 No.2

Background and Objectives : The overexpression of P-glycoprotein (Pgp) or multidrug resistanceassociated protein (MRP) confers multidrug resistance (MDR) to cancer cells. MDR cells could be sensitized to anticancer drugs when treated concomitantly with a chemosensitizer. In this study, orange peel have been screened for the development of chemosensitizers reversing MDR. Materials and methods : Expression of Pgp in AML-2/WT and AML-2/D100 were determined using western blot analysis and RT-PCR. Candidates for chemosensitizers were isolated, purified from orange peel using sephadex LH-20 column chromatography and silica-gel column chromatography, whose structure was determined using ^1H-NMR, ^13C-NMR, ^1H-^1H-COSY, 13C-NMR, EI-Mass, IR. Chemosensitizing effect of NP-28 on AML-2/DX100 over expressing Pgp and MRP was determined by the MTT assay. Membrane toxicity was evaluated by the RBC hemolysis test. Antioxidant effects were examined by using a fluorescence probe (2’-7’-dichlorofluorescein diacetate). Results : A potent candidate, NP-28, has a flavonoid nucleus with some methoxy moiety. NP-28 is believed to have high therapeutic index, being non-transportable inhibitor and possibly, of inhibiting other efflux pumps such as MRP and antioxidant effects. NP-28 is also unlikely to be a substrate of Pgp. NP-28 did not increase Pgp levels. Conclusion : NP-28 has a Chemosensitizing effect to reverse Pgp-mediated MDR by increasing the intracellular accumulation of drugs. Furthermore, they do not increase expression of Pgp, which can allow a long term use without the concern about Pgp activation. NP-28 is anticipated as an ideal second-generation flavonoid chemosensitizer and/or possibly other therapeutic agents by further investigation.

면내 지진파에 대한 부지응답해석

김효건,최홍석,손영호,최광규 동아대학교 건설기술연구소 1999 硏究報告 Vol.23 No.2

The site responses of seismic waves were considered when in-plane P and SV waves are incident to alluvial deposit of arbitrary shape. Parametric variables such as the incident angle and the dimensionless frequency and the sheat wave velocity ratio and the mass density ratio between the half-space and the allvial deposit were selected. For numerical analysis, the inhomogeneous alluvial deposit was modeled by using 8-node isoparametric finite elements and the surrounding homogeneous linear elastic soil half-space was modeled by using 3-node isoparametric boundary elements. The two elements at the interface were coupled together with the equilibrium condition of the tractions and the compatibility condition of the displacements.

p-type InP 표면에 미치는 H₂S 플라즈마 Passivation 효과

이영철,최병건,한교용 嶺南大學校 工業技術硏究所 1997 工業技術硏究所論文集 Vol.25 No.2

The effects of H₂S plasma passivation on p-type InP surface have been characterized by performing PL measurements. PL samples were fabricated under different RF power and different exposure time. After exposing them to H₂S plasma, their surface was covered by RF sputtered ITO film. Our PL results showed that RF power and exposure time should be optimized to obtain better surface passivation. In order to investigate surface type conversion by H₂S plasma, ITO/InP solar cell was fabricated and electrically characterized. The solar cell showed the typical I-V characteristic curve of a pn diode, which demonstrated the formation of pn junction by H₂S plasma.

제주 차귀도 연안해역 미생물 분포 및 이화학적 특성

문영건,김만철,이준백,송춘복,여인규,김종만,박근태,손홍주,최우봉,허문수 한국환경과학회 2006 한국환경과학회지 Vol.15 No.3

제대군인 취업지원 프로그램 구안

정철영,서우석,김성호,이예성,최동선,이종범,이성식,이건남,양안나,김성남 한국직업능력개발원 2007 직업능력개발연구 Vol.10 No.1

이 연구의 목적은 중·장기복무를 마치고 제대하여 재취업하고자 하는 제대군인들의 원활한 전직을 돕기 위한 제대군인 취업지원 프로그램의 개발방향과 개발안을 제시하는 데 있다. 이를 위해 국내·외에서 이루어지고 있는 제대군인 취업지원 프로그램의 실태를 분석하였고, 제대군인 취업지원 프로그램에 대한제대예정군인 및 제대군인과 기업체의 요구를 분석하여 시사점을 도출하였다. 그리고 이를 기초로 제대군인 취업지원 프로그램의 기본방향과 전체 흐름도, 세부 프로그램 개발안을 제시하였다. 이를 위해서 활용된 연구의 방법은 문헌연구, 조사연구, 전문가협의회 등이다. 이 연구를 통해서 제시된 제대군인 취업지원 프로그램의 개발방향과 개발안을 토대로, 일관되고 지속적인 수요자 중심의 제대군인 취업지원 프로그램의 개발이 가능할 것이다. The purpose of this study is to suggest plans and directions for developing. job-seeking support program for military veterans. The study is conducted through literature review, survey and interview. The results of this study are as follows: ⒧ basic development directions and flowchart of job-seeking support program for military veterans are suggested; and ⑵ development plans for sub-programs are suggested.