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.

응력 제한조건하의 신뢰성 기반 형상 최적설계

오영규(Young-kyu Oh),박재용(Jae-kyu Oh),임민규(Min-gyu Im),박재용(Jae-yong Park),한석영(Seog-young Han) 한국생산제조학회 2010 한국생산제조학회지 Vol.19 No.4

The objective of this study is to integrate reliability analysis into shape optimization problem using the evolutionary structural optimization (ESO) in the application example. Reliability-based shape optimization is formulated as volume minimization problem with probabilistic stress constraint under minimization max. von Mises stress and allow stress. Young's modulus, external load and thickness are considered as uncertain variables. In order to compute reliability index, four methods, i.e., reliability index approach (RIA), performance measure approach (PMA), single-loop single￢vector (SLSV) and adaptive-loop (ADL), are used. Reliability-based shape optimization design process is conducted to obtain optimal shape satisfying max. von Mises stress and reliability index constraints with the above four methods, and then each result is compared with respect to numerical stability and computing time.

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.

감성돔(Acanthopagrus schlegeli) 유래의 주화세포의 확립과 확립된 세포의 특성

임은영,강민수,오명주,정태성,정성주 한국어병학회 2003 한국어병학회지 Vol.16 No.3

감성돔 (Acanthopagrus schlegeli)의 비장에서 주화세포인 BSBS를 확립하고 세포의 특성을 검사하였다. BSBS세포는 60회 이상의 계대배양이 가능하였고 형태학적으로는 상피성 세포였다. 세포는 20℃, 10%의 FBS가 든 L-15배지에서 배양하는 조건에서 잘 자랐다. BSBS세포는 해양버나바이러스 (MABY Y-6), 잉어의 봄바이러스병바이러스 (SVCV), 넙치의 랍도바이스(HIRRV)와 연어바이러스 (CSV)를 접종했을 때 세포변성효과가 나타났다. 새로 확립된 주화세포는 앞으로 많은 바이러스병의 연구에 유용하게 사용할 수 있을 것으로 생각된다. A stable cell line, BSBS (black seabream spleen), was established from the cells in spleen of black seabream, Acanthopagrus schlegeli, and characterized. Subculture maintained more than 60 passages and mophologically, BSBS cell was epithelioid cell. The cells grew optimally at 20℃ in Leibovitz's L-15 medium supplemented with 10% fetal bovine serum with incubation temperature of 20℃. BSBS cells supported the growth of marine birnavirus (MABV Y-6), chum salmon reovirus (CSV), spring viremia of carp virus (SVCV) and hirame rhabdovirus (HIRRV). Thus, the new cell line may be useful for studying wide range of fish viruses.

Mini-implant를 이용한 III급 부정교합 환자의 협진 치료 : 문제중심의 교정치료

임동혁,김영신,조민아,김기성,양성은 대한치과교정학회 2007 대한치과교정학회지 Vol.37 No.4

자폐적 행동 양상을 보이는 아동과 어머니간의 애착 발달에 관한 분석적 연구

임숙빈,주세진,오민자,권미경,곽은영 대한간호학회정신간호학회 1994 정신간호학회지 Vol.3 No.1

This study was conducted to examine the feature of attachment and the main factors of attachment development between autistic child and his or her mother. Data was collected at Day Care Center for Children with Developmental Disorder in S National University Hospital through nurses's in S National University Hospital through nurses's participating observation, interview with the mothers, and review of nursing records, from April 2 to June 30, 1994. The subjects were all 6 children, one was a girl, the others were boys, and their mothers who participate at the sensory-integrative play for attachment promotion served at this center. Content analysis was done for data analysis. First, all data were categorized by main concepts, reciprocity and affect. Then these wee analyzd and discussed on the aspects of specificity, proximity, synchrony, joint attention, strong affect, emotional availability which were chosen as the components of attachment through literature review. The results of this study were summarized as follows : all subjects were underdeveloped, unstable and showed different level of mother-child attachment. But during the program their attachment behaviors improved little by little. The behaviors which represented specificity, proximity, and strong affect were increased considerably, on the other hand the behaviors which represented joint attention and emotional availability were scarce. The more mother and child had contact and interacted merrily, the more their attachment behaviors developed. Another important factors of attachment development in these cases were mother and child's each characteristics. Especially the child's autistic peculiarity, such as indifference, severe resistance, distracterbility, stereotype tendency, physical condition were major barriers of maintatining the mother-child interaction. Also mother's attitude to her child, raring skill and physical condition were influencing factors. A few mothers who were anxious and stubborn had much more difficulty to adjust to their children. The mother who had experienced happiness with her child, especially if the mother experienced more fun at the play by herself became more positive, active and flexible, and that mother-child interaction maintained much longer and improved. It was more critical to help them enjoy their interaction. Thus nurses had to plan and intervene more joyful and various play, and consider mother's need in addition to child's need. And The program should be strengthened to support the mother emotionally to maximize the therapeutic effect.

Carbamazepine Degradation by Photolysis and Titanium Dioxide Photocatalysis

Im, Jong-Kwon,Son, Hyun-Seok,Kang, Young-Min,Zoh, Kyung-Duk Wiley (John WileySons) 2012 Water environment research Vol.84 No.7

<P>We investigated the degradation of carbamazepine by photolysis/ultraviolet (UV)-C only and titanium dioxide photocatalysis. The degradation of carbamazepine by UV-only and titanium-dioxide-only (adsorption) reactions were inefficient, however, complete degradation of carbamazepine was observed by titanium dioxide photocatalysis within 30 min. The rate of degradation increased as initial carbamazepine concentration decreased, and the removal kinetics fit well with the Langmuir-Hinshelwood model. The addition of methanol, a radical scavenger, decreased carbamazepine removal, suggesting that the hydroxide radical played an important role during carbamazepine degradation. The addition of oxygen during titanium dioxide photocatalysis accelerated hydroxide radical production, thus improving mineralization activity. The photocatalytic degradation was more efficient at a higher pH, whereas the removal of carbamazepine and acridine (a major intermediate) were more efficient under aerobic conditions. The mineralization of carbamazepine during photocatalysis produced various ionic by-products such as ammonium and nitrate by way of nitrogen dioxide.</P>

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.

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.

우리나라 생명공학 연구 개발의 현황과 육성방향

오을임,박민희,이숙영 朝鮮大學校 社會科學硏究所 2000 社會科學硏究 Vol.21 No.2