[논문]ZCS를 이용한 간단한 long pulse CO2 레이저 전원

김태균,이임근,김희제 釜山大學校生産技術硏究所 2004 生産技術硏究所論文集 Vol.63 No.-

30Torr 이하 저압 공진기에서 ms order의 long pulse duration을 가진 간단한 펄스 CO2 레이저를 구현하였다. 레이저 시스템의 새로운 전원은 직접 상용전원을 스위칭한다. 이 새로운 전원의 방전 회로에는 정류기, 축전용 커패시터, 또는 전류 제한용 저항이 필요하지 않다. 레이저 출력을 제어하기 위해 펄스 반복률을 최대 60Hz까지 조절했고,SCR의 스위칭각은 30°에서 150°까지 변화시켰다. ZCS circuit과 PIC one-chip microprocessor는 SCR 게이트 신호를 제어하기 위해서 사용되었다. 18 Torr 압력,60Hz 의 펄스 반복률,SCR 스위칭각 90°에서 최대 레이저 출력 35 W를 얻었다. 또한 다른 CO2 레이저와 비교해서 long 펄스를 얻을 수 있었고 이는 대략 3ms(FWHM) 였다.

만성 통증 질환들의 새로운 분류 및 진단 기준 : 류마티스 관절염, 섬유근육통 및 척추관절염

김근태 고신대학교 의과대학 2011 고신대학교 의과대학 학술지 Vol.26 No.1

Rheumatoid arthritis, fibromyalgia, and spondylarthritis are important diseases causing chronic pain and disability in rheumatologic areas. The classification and diagnostic criterias of them were made on the basis of clinical features, radiologic and laboratory findings and have been used decades ago. According to the development of new knowledge about etiology and pathogenesis of rheumatic diseases, the need for new criteria has been increased. In recent years, new criteria for these diseases have been developed, and they allow the early assignment of diseases and early start of therapy. In this review, the author summarizes recent advances and changes in diagnosis of rheumatoid arthritis, fibromyalgia, and spondylarthritis.

신피질 세포에서 organic hydroperoxide에 의해 유발된 세포사망

김근태 고신대학교 의과대학 2009 고신대학교 의과대학 학술지 Vol.24 No.1

Background : Previous studies have shown that the hydrogen peroxide induces the cell injury through a lipid peroxidation-independent mechanism in renal epithelial cells. This study was therefore undertaken to examine the roles of lipid peroxidation in t-butylhydroperoxide (tBHP)-induced cell death to renal epithelial cells. Methods : Opossum kidney (OK) cell cultures, a renal tubular epithelial cell line, were used as the renal epithelial cell model. tBHP caused cell death in a dose-dependent manner over the concentration range of 0.05-2 mM. Results : The cell death was effectively prevented by the hydroxyl radical scavenger (dimethylthiourea), iron chelators (deferoxamine and phenanthroline), and antioxidants (DPPD and BHA), but not by the hydrogen peroxide scavenger catalase. tBHP caused a marked increase in lipid peroxidation, which was completely inhibited by DPPD and deferoxamine. tBHP-induced ATP depletion was prevented by deferoxamine and DPPD. Similar protective effects of antioxidants were observed in cell death induced by cumene hydroperoxide, another organic hydroperoxide. However, inorganic hydroperoxide (H2O2)-induced cell death was not altered by antioxidants. tBHP-induced apoptosis was prevented by DPPD and deferoxamine. Conclusions : These results indicate that organic hydroperoxide induces cell death through a lipid peroxidation-dependent mechanism, unlike inorganic hydroperoxide, in renal epithelial cells. 배경:신장 세뇨관 상피세포에서 inorganic hydroperoxide 인 H2O2가 lipid peroxidation-independent mechanism을 통해 세포 상해를 유도한다는 이전 연구 결과가 있었고, 본 연구에서는 신장 세뇨관 상피세포에 organic hydroperoxide인 t-butylhydroperoxide (tBHP)에 의해 유도된 세포사망에 있어 lipid peroxidation이 어떤 역할을 하는지 조사하였다. 방법 : 신피질 세포로는 Opossum Kidney (OK) cell이 이용되었다. tBHP는 0.05-2mM의 범위에서 농도 의존적으로 세포사망을 유도했다. 이러한 세포사망이 hydroxyl기 제거제인 dimethylthiourea, iron chelator인 deferoxamine과 phenanthroline, 항산화제인 DPPD와 BHA, 그리고 H2O2 제거제인 catalase에 의해 어떠한 차이를 나타내는 지를 관찰하였다. 결과 : 세포사망은 dimethylthiourea, deferoxamine과 phenanthroline, DPPD와 BHA에 의해 효과적으로 방지되었으나, catalase에 의해서는 방지되지 않았다. tBHP는 lipid peroxidation을 확연하게 증가시켰으며 이러한 효과는 DPPD와 deferoxamine에 의해 완전히 억제되었다. 또 tBHP에 의해 유도된 ATP 소모도 deferoxamine 과 DPPD에 의해 방지되었다. 항산화제의 이와 같은 방지효과가 다른 organic hydroperoxide인 cumene hydroperoxide에 의해 유도된 세포사망에서도 나타났으나, H2O2에 의해 유도된 세포사망은 영향을 받지 않았다. tBHP가 apoptosis를 유도하였으며, 이는 DPPD와 deferoxamine에 의해 방지되었다. 결론 : 이상의 결과는 신장 세뇨관 상피세포에서 organic hydroperoxide가 inorganic hydroperoxide와 달리 lipid peroxidation-dependent mechanism을 통해 세포사망을 유발함을 의미한다.

강낭콩의 식물체 부위와 생육시기에 따른 무기영양성분 함량과 흡수량에 대한 질소의 사용효과

오태근,이경아,송범헌 忠北大學校 農業科學硏究所 2012 農業科學硏究 Vol.28 No.2

This study was conducted to examine the nitrogen effects on uptake and utilization of major mineral nutrients of the kidney bean (Phaseolus vulgaris L.). The N treatments were five levels, 0, 3, 6, 9, 12 N kg/10a. The kidney bean was cultivated on the upland experimental field in the agricultural ???? research & extensions service of Chungbuk province. The contents and uptake amounts of mineral nutrients were investigated throughout the growth stages of the kidney bean. Higher content of total N in the stem was maintained until 8 days before flowering stage and then decreased gradually. Also, total N content of leaves was increased in the vegetative growth stage, and it was decreased rapidly to 8 days after the flowering stage, and then increased gradually to the initial maturity stage. Total N content of roots was tended to decrease until 8 days after the flowering stage, while that of seed was increased from the flowering stage to the maturity stage. The amount of uptake N of the shoot parts was increased until the flowering stage, maintained similarly from the flowering to 14 days after the flowering stage, and then increased rapidly to the maturity stage, while that of root was increased slowly to the flowering stage and then maintained similarly to the maturity.

비용 제약하에서의 소모성 동시조달부품의 최적구매량 결정

吳根泰,金明洙 水原大學校 1998 論文集 Vol.16 No.-

In this paper we consider the CSP requirement determination problem of new equipment(machine) system. For the newly procured equipment systems, mathematical analyses are made for the system which is constructed with the consumable parts to derive the associated CSP requirement determination model in mathematical expression. Based on these on these analyses, a mathematical model is derived for making an optimal CSP requirement determination subject to the constraint of satisfying any given fund limitation. We assume that the failure of a part follows a Poisson process. Firstly, the operational availability concept in CSP is defined and the relation between the general system availability and the operational availability concept in CSP is defined and the relation between the general system availability and the operational availability is established. Secondly, the problem is formulated as the operational availability maximization problem that should satisfy the fund limitation, and then, using the generalized Lagrange multipliers method, the optimal solution procedure is derived.

방법으로서의 중국 : 중국인의 관점'에서 옥시덴탈리즘까지 from China Centered Approach to Occidentalism

車泰根 중국어문연구회 2001 中國語文論叢 Vol.20 No.-

In recent years, many scholars of sinology have concerned with the methodology of sinology, They all have the similar tendencies, that is, they criticized the chinese studies of the west published before 1970's because of westcentrism or ethnocentrism, They insisted forwardly that one observe China through inner eye, and suggested a kind of new approach, such as China centered approach. Paul A. Cohen classified some tendencies towards the previous Chinese studies into three kinds of models: impact-response model, tradition-modernity model and imperialism model. These models were based on West centered monistic view of history. On the contrary, Cohen, Mizoguchi Y□, Lydia H. Liu, Xiaomei Chen, David L. Hall and Roger T. Ames, who this essay deal with, not only show a pluralistic view of history and cross-cultural approaches to Chinese studies, but also argue that one should study china from inner view(or with empathetic method), within the context of chinese history. This review will analyze the following scholars' magnum opus around the methodology of sinology: Paul A. Cohen, Discovering History in China: American Historical Writing on the Recent Chinese Past, New York: Columbia University Press, 1984; Mizoguchi Yu­zo­, China as a method, Tokyo: Tokyo University, Press, 1989; Lydia H. Liu. Translingual Practice: Literature, National Culture, and Translated Modernity - China,1900-1937. California: Stanford University Press, 1995. and Interlinguistic Writing, Shanghai: Shanghai sanlian shudian, 1999; Xiaomei Chen. Occidentalism: A Theory of Counter-Discourse in Post-Mao China. Oxford: Oxford University Press, 1994. David L. Hall, and Roger T. Ames, Thinking through Confucius, Albany: State University of New York Press, 1987. and Thinking from the Han: Self, Truth, and Transcendence in Chinese and Western culture, Albany: State University of New York Press, 1998.

측두하악 관절의 재건을 위한 늑연골 이식의 효과

김태규,정기돈,신상훈,김성길,이성근,박상준,서종천 大韓顎顔面成形再建外科學會 1996 Maxillofacial Plastic Reconstructive Surgery Vol.18 No.3

We performed costochondral grafting in mmandibular reconstruction including condyle replacement in 5 patients which have 4 cases of ameloblastoma, 1 case of resorption of left condyle due to osteomyelitis. We harvested the 6 th costochondral cartilage of unaffected side. No specific complications were appeared with unexpected fracture of costochondral junction and infection of operation site, These patients show 30-45mm at month opening, near normal of affected side, near normal or normal of unaffected side at lateral excursion. Postoperative coureses was uneventful with improved cosmetic and functional results. Our report is indicated that the costochondral graft is satisfactory to reconstruct mandibular defect including condyle replacement, especially in growing patients.

실린더 후류를 이용한 아음속 디퓨저 유동의 제어에 관한 연구

오대근,윤복현,김태호 국립7개대학공동논문집간행위원회 2005 공업기술연구 Vol.5 No.-

The present study addressed a computational work to investigate the influence of a turbulent wake flow on the pressure recovery of subsonic diffuser. The turbulent wake is generated by a cylinder with a small diameter, which is installed at the diffuser inlet of a 2-dimensional diffuser Computation are applied to three-dimensional steady Navier-Stokes equations. The computational results are qualitatively well compared to existing experimental results. The results show that the diffuser pressure recovery of the subsonic diffuser is dependent on the diameter and location of the cylinder. It is found that a certain diameter and location of cylinder to generate the turbulent wake give a better pressure recovery, compared with no cylinder flow

중국 근대사상의 전환논리 : 자연법과 변법 A Law of Nature and A Changing of the Laws 康有爲 사상을 중심으로

車泰恨 中國語文硏究會 2003 中國語文論叢 Vol.25 No.-

This article is a study on the China modern thought, especially Kang You Wei's Thought. Generally The change that is from a law of nature to an artificial law is regard as a characteristic of modern thought. The value and organization is said to be on the basis of a law of nature in the traditional thought of china, preticular, zhuzi school. In the end of 19th century, Kang You Wei didn't admit a law of nature, and insisted that the current value and regulation be consist of artificial laws. Furthermore, All values is under the influence of topography and the state of affairs. He transformed a sage' image as a moralist into a reformer. He thought that "saint-hood" was decided by His ability of knowledge not by His moral cleanness.

단일 범용설비 운영을 위한 (r, Q) 정책

오근태 한국경영과학회 1992 한국경영과학회지 Vol.17 No.3

This paper considers an (r, Q) policy for operation of a multipurpose facility. It is assumed that whenever the inventory level falls below r, the model starts to produce the fixed amount of Q. The facility can be utilized for extra production during idle periods, that is, when the inventory level is still greater than r right after a main production operation is terminated or an extra production operation is finished. But, whenever the facility is in operation for an extra production, the operation can not be terminated for the main production even though the inventory level falls below r. In the model, the demand for the product is assumed to arrive according to a compound Poisson process and the processing time required to produce a product is assumed to follow an arbitrary distribution. Similarly, the orders for the extra production is assumed to occur in a Poisson process and the extra production processing time is assumed to follow an arbitrary distribution. It is further assumed that unsatisfied demands are backordered and the expected cumulative amount of demands is less than that of production during each production period. Under a cost structure which includes a setup / production cost, a linear holding cost, a linear backorder cost, a linear extra production lost sale cost, and a linear extra production profit, an expression for the expected cost per unit time for a given (r, Q) policy is obtained, and using a convex property of the cost function, a procedure to find the optimal (r, Q) policy is presented.