편심 압축력을 받는 스테인리스 각형강관 기둥의 곡률형상에 따른 좌굴내력에 관한 실험적 연구

장호주,서성연,양영성 대한건축학회 2005 大韓建築學會論文集 : 構造系 Vol.21 No.2

This study is a series of experimental investigation on the buckling strengths of eccentrically compressed cold-formed stainless steel square hollow section columns. The principal parameters in this study are slenderness ratios(λ=30, 50, 70) and magnitude of eccentricity e(0, 2.5, 5.0, 7.5. 10cm) on the direction of end-moment. The direction of end-moment means 3 different bending moment distributions. Objectives of this paper are to obtain the maximum loads and moments by performing an experimental work and to compare the experimental behaviors with the design standard curves, AIK-LSD and AISC-LRFD, AIJ-LSD, SIJ-ASD curves. The ultimate buckling strengths and bending moments of square section members were evaluated by a method in accordance with design standard curves. Therefore this paper attempts design standard for the use of these stainless steel columns as structural compression members. The numerically obtained ultimate buckling strengths and bending moments design standard curves of beam-columns showed a reasonably good agreement with the available experimental results.

Global-MAHN에서 라우팅 오버헤드 개선에 대한 연구

張良根,金玄旭,李光培,吳世德,裵振勝,金在浩 明知大學校 産業技術硏究所 2007 産業技術硏究所論文集 Vol.26 No.-

In this Paper, we studied the mechanism that increases the network reliability and decreases network load in GMAHN environment based on the AODV routing protocol. This proposed algorithm is the research on the algorithm, minimizing network overhead by preventing unnecessary network overhead previously and adapting Local repair mechanism to efficient data transmission when route error happens in network, in GMAHN environment. To evaluate the proposed algorithm's performance, we analyzed the proposed algorithm and adapting in various experiment environment according to 5 experiment viewpoint such as node movement, gateway network zone, mobile node number, flow number. After evaluating the experiment, we confirmed better network improvement altogether through following result such as total average data reception rate's increase, average data transmission time's decrease, network overhead's decrease than existing GMAHN algorithm.

역류식 충진탑에서 수력학적인 분석과 이산화탄소의 탈착에 관한 연구

楊善惠,崔東勳,지혜미,金恩貞,金彰昊 동아대학교 환경문제연구소 1996 硏究報告 Vol.19 No.1

This study was carried out to interpret hydraulic behavior and CO₂gas desorption in countercurrent packing tower which packed 50 mm plastic Hiflow-ring. The results are as follows: 1. To compare with conventional packing, 50mm Hiflow-ring could save energy because of low pressure drop under high load. 2. As relative error between calculated value and investigated value was less than 6% in the loading point and flooding point we found that we can predict results mathematically which occurres in the packing tower. 3. The unique magnituteds of packing which was used are as follows. C_(L) = 2.1×10^(-4), n = 0.787 so we can predict efficency which occurres.

Ribbon형 Co1-x Crx (x=0.27, 0.29, 0.30, 0.32, 0.35) 합금의 자기특성

장현숙,김미양,이장로,이용호 숙명여자대학교 자연과학연구소 1994 자연과학논문집 Vol.- No.5

급냉법으로 리본형 결정질 Co1-x Crx (x=0.27, 0.29, 0.30, 0.32, 0.35)합금을 제조하여 Cr의 조성에 따른 자기적 특성을 조사하였다. 포화자화값은 벌크값보다 컸지만 박막의 경우보다는 작았다. Cr의 함량이 증가함에 따라 포화자화값은 감소하였다. 27 at.% Cr의 경우를 예외로 하면 Cr 함량 증가에 따라 결정립의 크기는 감소하였고, 항자력은 증가하였다. 리본형 Co1-x Crx 는 포화자화값의 온도 의존성이 비정질 시료인 경우와 유사한 경향을 나타내었으며 Cr의 함량이 증가할수록 Curie온도(Tr)는 감소하였다. Cr 함량의 증가에 따라 exchange interaction의 평균자승거리<r²>와 spin wave stiffness 상수D는 감소하는 경향을 나타내었다. 천이금속(Co)의 원자당평균 자기모멘트는 Cr의 증가에 따라 선형적으로 감소하였다. The magnetic cnaracteristics of crystalline Co1-x Crx (x=0.27, 0.29, 0.30, 0.32, 0.35) ribbons prepared by the rapid solidification were investigated. The saturation magnetization for ribbon was greater than that for bulk alloys containg the same amount of Cr. but smaller for the films. The grain size of ribbon became smaller and coercive force increased with increasing Cr contents except case of 27 at.% Cr. The saturation magnetization decreased with increasing Cr contensts. The temperature dependence of saturation magnetization for Co1-x Crx ribbon showed the similar behavior as the amorphous alloy and the Curie temperatures were decreased with the increase of Cr contents. The spin wave stiffness constant and the mean square range of exchange interaction, also were decreased. The average magnetic moment per transition metal atom was linearly decreased with increasing the contents of Cr.

축력과 양단 대칭모멘트를 받는 스테인리스 원형강관 기둥의 좌굴내력에 관한 실험적 연구

장호주,서성연,양영성 대한건축학회 2005 大韓建築學會論文集 : 構造系 Vol.21 No.3

This study is a series of experimental investigation on the buckling strengths of eccentrically compressed cold-formed stainless steel CHS(circular hollow section) columns. The principal parameters in this study are slenderness ratios(L_(k)/r = 30, 50, 70) and magnitude of eccentricity e(0, 2.5, 5.0, 7.5, 10㎝) on the symmetrical end moment. Objectives this study are to obtain the maximum loads by performing an experimental work and to compare the experimental behaviors with analytical results. The ultimate buckling strength of CHS members are evaluated by a numerical method in accordance with the axial force-bending moment(P-M) interaction curves. The behavior of each specimen is displayed in the form of moment angle(M- θ) relationship. The numerically obtained ultimate buckling interaction curves of beam columns show a reasonably good agreement with the available experimental results of slenderness ratios(L_(k)/r = 30, 50). But experimental results of slenderness ratios 70 were below M-P interaction curve.

축력과 양단 대칭모멘트를 받는 스테인리스 각형강관 기둥의 좌굴내력에 관한 실험적 연구

장호주,서성연,양영성 대한건축학회 2005 大韓建築學會論文集 : 構造系 Vol.21 No.2

This study is a series of experimental investigation on the buckling strengths of eccentrically compressed cold-formed stainless steel square hollow section columns. The principal parameters in this study are slenderness ratios(λ=30, 50, 70) and magnitude of eccentricity e(0, 2.5, 5.0, 7.5, 10cm) on the symmetrical end-moment. Objectives of this paper are to obtain the maximum loads by performing an experimental work and to compare the experimental behaviors with analytical results. The ultimate buckling strength of square section members are evaluated by a numerical method in accordance with the bending moment-axial force(M-P) interaction curves. The behavior of each specimen is displayed in the form of moment-angle(M-θ) relationship. The numerically obtained ultimate buckling interaction curves of beam-columns showed a reasonably good agreement with the available experimental results.

편심 압축력을 받는 스테인리스 원형강관 기둥의 곡률형상에 따른 좌굴내력에 관한 실험적 연구

장호주,서성연,양영성 대한건축학회 2005 大韓建築學會論文集 : 構造系 Vol.21 No.3

This study is a series of experimental investigation on the buckling strengths of eccentrically compressed cold formed stainless steel CHS(circular hollow section) columns. The principal parameters in this study are slenderness ratios( λ=30, 50, 70) and magnitude of eccentricity e(0, 2.5, 5.0, 7.5, 10㎝) on the direction of end moment. The direction of end-moment means 3 different bending moment distributions. Objectives this study are to obtain the maximum loads and moments by performing an experimental work and to compare the experimental behaviors with the design standard curves, AIK-LSD and AISC-LRFD, AIJ-LSD, SIJ-ASD curves. The ultimate buckling strengths and bending moments of circular section members are evaluated by a method in accordance with design standard curves. Therefore this paper attempts design standard for the use of these stainless steel columns as structural compression members. The numerically obtained ultimate buckling strengths and bending moments design standard curves of beam columns show a reasonably good agreement with the available experimental results.

분만 후 심한 저혈당이 동반된 림프구성 뇌하수체염 1예의 경과 관찰

손장명,고승현,안유배,주강,이정록,양성은,송기호,손호영,전정수 대한내분비학회 2003 Endocrinology and metabolism Vol.18 No.3

저자들은 출산 후 발생한 심한 저혈당을 주소로 내원한 31세 여자 환자에서 뇌 자기공명영상검사에서 뇌하수체종괴가 관찰되고 복합 뇌하수체 기능검사 결과전반적인 뇌하수체 기능저하증의 소견을 보여 림프구성 뇌하수체염을 진단하고, 호르몬 보충요법만으로 경과를 관찰하여 호전된 예를 경험하였기에 문헌 고찰과 함께 보고하는 바이다. Lymphocytic hypophysitis, an inflammatory disease of the pituitary gland that is often associated with pregnancy, is caused by autoimmune destruction of the pituitary gland evidenced by diffuse inflammatory cell infiltration of the pituitary gland and some kinds of detectable autoantibodies. We report a case of lymphocytic hypophysitis in a 31-year-old woman presenting with severe hypoglycemia and hyponatremia after delivery. Hormonal study revealed panhypopituitarism and magnetic resonance imaging with enhancement showed the bulging contour of the right side pituitary gland with an ill-defined mass-like lesion and nodular thickening of the stalk The patient's symptoms and biochemical data improved greatly with replacement of L-thyroxine and glucocorticoid. Partial recovery of panhypopituitarism was also seen. The follow-up tests revealed dramatic resolution of the pituitary lesion (J Kor SOC Endocrinol 1 8 : 3 25 -33 1, 2003).

Southern Blot Hybridization법을 이용한 악성 림프종의 면역유전형에 관한 연구

전호종,기근홍,김윤신,이미숙,이미자,장원재,장숙진,박영진,정춘해,정종훈,양성훈,이광민 조선대학교 1994 The Medical Journal of Chosun University Vol.19 No.2

Immunogenotyping using gene rearrangement analysis has emerged as a precise laboratory aid in the diagnosis and classification of malignant Iymphoid neoplasms. The lineage and clonality of the malignant Iymphoid neoplasms can be identified by the demonstration of rearrangements of antigen receptor genes of the immunoglobulin and T-cell receptor genes. The analysis of the gene rearrangements on the malignant Iymphoid neoplasms are also useful as a sensitive unique clonal markers to detect early recurrence in patients with malignant Iymphoid neoplasms after treatment. To analyze the sensitivity and specificity of gene rearrangements in the diagnosis of malignant Iymphoid neoplasms. 24 cases of malignat Iymphoma were examined by Southern blot hybridization using CTβ-T cell receptor β chain gene-DNA probe and JH-immunoglobulin heavy chain gene-DNA probe. The results of the immunogenotypings using Southern blot hybridization disclosed high correlation between the immunophenotyping using immunohistochemical stain with monoclonal antibodies (B-cell Iymphoma 84.2%. T-cell Iymphoma 75% ). The analysis of the gene rearrangement of the angioimmunoblastic lymphadenopathy(AILD) and unclassifiable Iymphoma using immunohistochemical stain could resolve the monoclonality and lineage . Rearranged bands to the CTβDNA probe were observed in one case out of 2 cases of AILD. One case of unclassifiable Iymphoma showed rearranged bands to the CTβ DNA probe. There were no rearrangements in reactive follicular Iymphoid hyperplasia and paracortical Iymphoid hyperplasia. In conclusion, DNA gene rearrangement study should be applied to differentiate the clonality and cell lineage in the malignant Iymphoma with indistinctive immunophenotype.

針葉樹材의 南洋闊葉樹 문틀材 代替 可能性 調査

姜琥陽,張相埴,李華珩 충남대학교 농업과학연구소 1994 농업과학연구 Vol.21 No.2

Since the supply of the Southeast Asian tropical timber decreases and its price steeply increases in the international lumber market, door and window frame manufacturers in this country are eagerly searching for their substitutes. This is the first step to replace Southeast Asian tropical timber by low grade North American softwoods. whose reliable and steady supply is expected, but their appearances are not as good as the tropical timber. In this study, knot distribution on the softwood boards and their warp were examined. The yield and production cost were calculated. The average number of knots on a door frame were 7.2 for Douglas-fir and 3.4 for Western hemlock. Only 11% of the knots of Douglas-fir door frames are larger than 5cm in diameter, while are 35% of the knots of Western hemlock. The deformations of door frames, after 2 months air-drying, were measured with a warp table. The deformation, of Western hemlock door frames were mostly less than 6mm, while those of Douglas-fir distributed in the range of 0.5 and 9.5mm. The yield of Western hemlock is higher than that of Douglas-fir. It can be concluded that the door frames made of the softwoods are compatible with those made of the tropical timber in most aspects except appearance.