복강경을 이용한 종양학적 우반대장절제술: 우측 대장혈관의 구조와 림프절 전이 양상의 연구

최규석,전수한 대한대장항문학회 1997 Annals of Coloproctolgy Vol.13 No.4

上·下向流 多段式 嫌氣性 固定層 反應器에서 음이온과 양이온의 反應經路에 關한 硏究

崔錫圭 서라벌대학 1992 논문집 Vol.6 No.-

The primary objective of this research program is to provide a fundmental mechanism of involved reactions using a modified upflow and downflow multistage perked bed bioreactor. As a first stage of this reaserch program, the following theoretical principles was applied. 1) Principle of electroneutrality where the molar concentrations of cation and anion in solution are the same. 2) Relationship between the concentration of bicarbonate anion and pH as follows [HCO_3^]=K_11P_TY_(CO_2)10^(pH-K1) Based upon the above two principles, a series of experimental works was conducted to elucidated the relationship between the concentration of CO2 and pH related in the concentrations of cations and anions.

THMs 저감을 위한 고도정수처리 기술 연구

강석규,오재원 大田産業大學校 1999 한밭대학교 논문집 Vol.16 No.1

At the time when the application of advanced water treatment process is required, a pilot plant consisting of ozonation, granular activated carbon(GAC) column and conventional water treatment treating 30㎥/day was conceived. As Daechung lake was in eutrophicated state, treatment of the polluted raw water by the pilot plant was studied. Especially, TOC removal which is the THM precursor and the optimum operating condition were investigated. The results obtained were as follows ; 1. Advanced water treatment using the pilot plant was effective for reducing THM formation potential : at the early stage - 90% reduction, after 8, month - 30% reduction were achieved. 2. Removal efficiency of organic pollutants(COD_Mn, TOC, DOC) by ozonation was about 10%, and it was not particularly sucessful comparing to GAC alone. 3. In order to remove such slow diffusivity pollutants as DOC, TOC in GAC column, it was confirmed that the bed depth was one of the most important design parameters. 4. For GAC column, imported GACI showed the better removal efficiency than GAC2(domestic product).

신뢰성 지수에 의한 위상최적화

임민규,박재용,황승민,오영규,박재용,한석영 한국공작기계학회 2009 한국공작기계학회 춘계학술대회논문집 Vol.2009 No.-

The objective of this work is to integrate reliability analysis into topology optimization problems. The reliability index determines design domain and uncertainty value. The elemental sensitivity numbers are calculated from finite element analysis and then converted to the nodal sensitivity numbers in the design domain. A mesh-independency filter using nodal variables is introduced to determine the addition of elements and eliminate unnecessary structural details below a certain length scale in the design. To further enhance the convergence of the optimization process, the accuracy of elemental sensitivity numbers is improved by its historical information. Application of the RBTO model gives a different topology relative to DTO. It is found that the RBTO model yields more reliable optimal topologies than those produced by DTO.

항갑상선제로 치료한 그레이브스병 환자의 관해예측인자

남일송,윤여일,김선규,김용현,이주영,목지오,윤석기,김철희,김영선,변동원,서교일,유명희 순천향의학연구소 2001 Journal of Soonchunhyang Medical Science Vol.7 No.2

Background: Most cases of Graves' disease have been treated by antithyroid drugs in Korea. The major drawbacks of antithyroid drugs are the relative high rate of relapse and the inconvinience of long term therapy. Measurement of TBII and TRH stimulation test have been considered as the most reliable tests predicting relapse, but the predictive power is not high enough to use in clinical situation. This study was performed to find good prognostic indicators in Graves' disease patients after the discontinuation of antithyroid drug therapy. Subjects and methods : We restrospectively evaluated 96 patients with Graves' disease who showed normal TRH test at the end of antithyroid drug therapy and were followed for more than one year. Serum T3, T4, T3/T4 ratio, TBII, Anti-TPO Ab and TGAb levels were measured at the time of diagnosis and at the end of therapy. Two to three months after withdrawal of antithyroid medication, serum TSH and free T3 responses to TRH were examined. These parameters were compared between the relapse group and the remission group. Results : Among the 96 patients, 22 patients(22.9%) relapsed(Group Ⅱ) and 74 patients(77.1%) remained in remmision(Group Ⅰ). No significant difference was observed between the relapse and the remission group in clinical parameters, serum T3, T4, TSH, T3/T4 ratio, TBⅡ and Anti-TPO Ab determined before and after treatment. Serum TSH and free T3 levels measured after TRH stimulation were also similar in both groups. Serum TGAb levels determined at the end of treatment were significantly higher in the remission group(p<0.05). Relapse following the discontinuation of therapy occured within 24 months in 72.7% of the relapsed cases. After 24 months, relapse rate was reduced significantly. Conclusion : These results suggest that high serum TGAb levels could be a favorable prognostic indicator for the long term remission of Graves' disease treated with antithyroid drugs, and may suggest that Hashimoto's thyroiditis is combined with Graves' disease in those patients.

道德的 危態에 대한 經濟的 對應 方案

高良坤,崔錫奎 全北大學校 1996 論文集 Vol.42 No.-

The efficiency of a competitive market equilibrium depends on all of the decentralized decision-makers having full information. The market mechanism itself plays an informational role by conveying information in the form of relative prices to decision-makers about the relative costs and benefits of different actions. It is obvious that perfect insurance and financial markets of the type required for pareto optimality do not exist on practice. It is useful to consider the reasons why insurance and financial markets may fail to exist and why those that do exist may not exploit all of the mutual benefits to risk-sharing. Two types of informational externalities impede the functioning of insurance and financial markets, generally referred to as adverse selection and moral hazard. One way to distinguish between adverse selection and moral hazard is to remember that adverse selection in a problem of asymmetric information before entering into a transaction, whereas moral hazard is a problem of asymmetric information after the transaction has occurred. The problems created by adverse selection and moral hazard are an important impediment to well functioning insurance and financial markets, so market failure occurs because of those problems. Hence the purpose of this paper is to examine and analysis the problems of adverse selection and moral hazard, and then to seek the economically corresponding schemes of asymmetric information from adverse selection and moral hazard. For this purpose, this paper consists of four major sections Chapter Ⅰ involves the necessity, the purpose of this study. Chapter Ⅱ. explains the nature of risk, peril and hazard. In chapter Ⅲ. this paper will analysis the market failure from the asymmetric information of adverse selection and moral hazard. Also it explains the theoretical models of moral hazard. Finally chapter Ⅳ offers the economically corresponding schemes of the problems from adverse selection and moral hazard, and the conclusion. That is, there are some solutions such as lump-sum tax-financed subsidies on locks·burglar and smoke alarms, private production and sale of information, government regulation, financial intermediation, collateral and net worth, monitoring and enforcement of restrictive covenants etc.

적응 루프법을 이용한 진화적 구조 위상 최적설계

황승민,박재용,임민규,오영규,한석영 한국공작기계학회 2009 한국공작기계학회 춘계학술대회논문집 Vol.2009 No.-

This paper presents a reliability-based topology optimization (RBTO) using bi-directional evolutionary structural optimization (BESO). Topology optimization is formulated as volume minimization problem with probabilistic displacement constraint. Young's modulus, external load and thickness are considered as uncertain variables. In order to compute reliability index, four methods, i.e., RIA, PMA, SLSV and ADL(adaptive-loop), are used. Reliability-based topology optimization design process is conducted to obtain optimal topology satisfying displacement and reliability index constraints with the above four methods, and then each result is compared with respect to numerical stability and computing time.

ESO기법을 이용한 신뢰성 기반 형상 최적설계

오영규,박재용,황승민,임민규,박재용,한석영 한국공작기계학회 2009 한국공작기계학회 춘계학술대회논문집 Vol.2009 No.-

This paper presents a reliability-based shape optimization (RBSO) using the evolutionary structural optimization (ESO). An actual design involves uncertain conditions such as material property, operational load and dimensional variation. The deterministic optimization (DO) is obtained without considering uncertainties related to uncertainty parameters. However, the RBSO can consider the uncertainty variables because it has the probabilistic constraints. In order to determine whether the probabilistic constraint is satisfied or not, simulation techniques and approximation methods are developed. In this paper, the reliability-based shape design optimization method is proposed by utilizing the reliability index approach (RIA), performance measure approach (PMA), single-loop single-vector (SLSV), adaptive-loop (AOL) are adopted to evaluate the probabilistic constraint. In order to apply the ESO method to the RBSO, a sensitivity number is defined as the change in the displacement. Numerical examples are presented to compare the DO with the RBSO. The results of design example show that the RBSO model more reliable than deterministic shape optimization.

순차적 크리깅기법을 이용한 미소혼합기의 최적화

박재용,유진식,황승민,임민규,오영규,김용대,한석영,맹주성 한국공작기계학회 2008 한국공작기계학회 추계학술대회논문집 Vol.2008 No.-

An active micro-mixer, which is composed of an oscillating micro-stirrer in the micro-channel to provide effective mixing was optimized. The effects of molecular diffusion and disturbance by the stirrer were considered with regard to two types of mixer models: the simple straight micro-channel and micro-channel with an oscillating stirrer. Two types of mixer models were studied by analyzing mixing behaviors such as their interaction after the stirrer. The mixing was calculated by Lattice Boltzmann methods using the D2Q9 model. In this study, the time-averaged mixing index formula was used to estimate the mixing performance of time-dependent flow. The mixing indices of the two models were compared. From the results, it was found that the mixer with an oscillating stirrer was much more enhanced' and stabilized. Therefore, an approximate optimization of an active micro-mixer with an oscillating stirrer was performed using Kriging method with OLHD (Optimal Latin Hypercube Design) in order to determine the optimal design variables. The design parameters were established as the frequency, the length and the angle of the stirrer. The optimal values were obtained as 1.5754, 0.803D and ±45°, respectively. It was found that the mixing index of the optimal design increased by 83.36% compared with that of the original design.

폐모세포종 : 1례보고 A Case Report

최영호,서홍주,임영혁,김정중,박성강,이석기,임진수,김은규 조선대학교 2001 The Medical Journal of Chosun University Vol.26 No.2

Pulmonary blastoma is a very rare primary neoplasm of the lung. We experienced a case of pulmonary blastoma in a 40 years old man. The mediobasal segmentectomy of the right lower lobe was performed. The patient was discharge on the postoperative days 6. There is no evidence of recurrence or metastasis on followup study during 7 months period after operation.