http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Junyong Jang,Su-gil Cho,Su-Jin Lee,Kyu-Seob Kim,Ji-Min Kim,Jung-Pyo Hong,Tae Hee Lee IEEE 2015 IEEE transactions on magnetics Vol.51 No.3
<P>Reliability-based robust design optimization (RBRDO) is a notable method to secure the quality and feasibility of performances from uncertainties. In this paper, geometric uncertainties of a stator sheet that can occur during a stamping process are considered as the uncertainty of controllable variables. Then, as the uncertainty of uncontrollable variables, skew angle due to inexact lamination is considered. No researches on the effect of this uncertainty have been performed. To analyze the effects of the uncertainties, the kernel density estimation (KDE) was employed to estimate the distribution because of its convenience, flexibility, and robustness. Then, RBRDO with the KDE is performed and the optimum results are compared with real data measured from manufactured motors.</P>
Jang, Junyong,Lee, Jin Min,Cho, Su-gil,Kim, Saekyeol,Kim, Ji-Min,Hong, Jung-Pyo,Lee, Tae Hee IEEE 2018 IEEE transactions on magnetics Vol.54 No.3
<P>In rotating motors, an electromagnetic analysis using finite-element analysis is performed according to the time interval such as the steps of the rotation angle. If the uncertainty of time variable is necessary to be handled, the time interval should become smaller than uncertainty values. It causes an increase of the cost even if the surrogate model is applied. Thus, space-time kriging surrogate model is proposed to consider time variable as well as space variable in the design stage. The proposed model handles time variable and predicts responses between time intervals to obtain outputs for the tiny uncertainty of time variable. The performance of prediction is verified with simulation data and then the reliability estimated by the proposed model is compared with measured data from manufactured prototypes.</P>
( Junyong Jang ),( So-my Koo ),( Ki-up Kim ),( Hyeon-jong Yang ),( Suyeon Park ),( Sangyoung Kim ) 대한결핵 및 호흡기학회 2021 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.129 No.-
Background There is limited head-to-head comparative studies on the effects of EGFR-TKIs used in advanced EGFR mutant non-small cell lung cancer (NSCLC). The purpose of this study is to analyze the real-world clinical data of the target therapies (afatinib, erlotinib, gefitinib, and osimertinib) as a first-line treatment in patients with NSCLC with brain metastasis. Method The data were retrospectively collected from patients who were diagnosed with advanced NSCLC within 60 days prior to receiving EGFR-TKIs using common data model (CDM) from four Soonchunhyang University hospital. Primary outcome was the time to treatment failure, and secondary outcome was overall survival and adverse drug reaction (ADR) : leukopenia, neutropenia, anemia, thrombocytopenia, hepatitis, and kidney injury. The time to treatment failure was defined as the duration of EGFR-TKI treatment as first-line treatment. Result In total of 437 patients were included (afatinib, 88 [20.1%]; erlotinib, 80 [18.3%]; gefitinib, 245 [56.0%]; Osimertinib, 24 [5.5%]). The median time to treatment failure was 164.0 days (interquartile range [IQR], 52.5 to 382.5 days) in afatinib group, 83.5 days (IQR, 24.5 to 279.8 days) in erlotinib group, 171.0 days (IQR, 42.0 to 411.0 days) in gefitinib group, and 139.5 days (IQR, 59.8 to 212.0 days) in Osimertinib group. Of the 437 patients, 104 patients had brain metastasis. Among patients with brain metastasis, gefitinib also showed the longest median time to treatment failure (201.0 days [IQR, 42.0 to 420.0 days]). Anemia was more common in the gefitinib group (n = 89, 40.3%). Thrombocytopenia is more common in erlotinib group (n=28, 35%) and osimertinib (n=9, 37.5%). Creatinine increase was more common in gefitinib (n=67, 27.4%) and osimertinib (n=6, 25.0%). Conclusion As the first-line treatment for advanced EGFR mutant NSCLC, gefitinib showed the longest treatment duration. There are limitations to analyzing survival of patients with CDM, and further studies are needed.
코깅 토크와 토크 리플 저감을 위한 800W급 소형 SPM 전동기 다중목적 최적 설계
장준용(Junyong Jang),조수길(Su-gil Cho),이수진(Su-Jin Lee),홍정표(Jung-Pyo Hong),이태희(Tae Hee Lee) 한국자동차공학회 2011 한국자동차공학회 부문종합 학술대회 Vol.2011 No.5
SPM(Surface-mounted permanent magnet) motor is widely used for variety of fields, but it is necessary for reducing torque ripple and cogging torque which result in noise and vibration. Since the configuration of the motor has great impact on these responses, study related shape optimization is proceeding actively. However, these responses cannot design easily for general optimization technique because of trade off relation. So, this paper presents multi-objective optimization of stator and rotor in a SPM motor. Also kriging metamodel and global optimization technique is applied, because multi-objective function is nonlinearity and has multiple local optimums.
상관함수에 따른 분할영역 크리깅모델의 1차 미분연속 연구
장준용(Junyong Jang),이진민(Jin Min Lee),이태희(Tae Hee Lee) 대한기계학회 2011 대한기계학회 춘추학술대회 Vol.2011 No.4
공학에서 효율적인 최적설계를 위하여 크리깅모델을 널리 사용하고 있다. 하지만 설계변수에 대한 표본점이 많아지면 크리깅모델을 구성할 때 상관계수를 결정하는 최우량추정과정이 오래 걸리는 어려움이 있다. 특히 시간-변화 동적 응답에 대한 이중순환 다중응답접근법 기반 통계적 공간-시간 메타모델에서 취급해야 할 시간변수에 대한 표본점이 상당히 많다. 따라서 시간변수를 효율적으로 다루기 위하여 시간분할영역 메타모델링 기법이 개발되었다. 본 논문에서는 분할영역의 경계점에서 크리깅모델의 1차 미분연속성과 분할영역 크리깅모델의 수치적 안정성을 검증한다. 그리고 수학예제를 통하여 상관함수에 따른 경계에서의 연속성에 대해 비교 분석한다. In engineering fields, Kriging model has been widely used to improve the efficiency of optimization. However, if the number of sample point of variables increase, it is time-consuming to build Kriging model because of maximum likelihood estimation(MLE) determining coπelation parameter. Especially in double-loop multiple response approach based statistical space-time metamodel for time-variant dynamic responses the number of time presampled point is much more than the number of space variable. Thus split time region(STR) metamodeling technique is developed for handling time-variable efficiently. In this research, we verify C1-continuty and numerical stability of split region Kriging model at boundary points. And we carry out some mathematical examples for comparing differential value according to coπelation functions at boundary point.
대체모델의 정확성 및 강건성 향상을 위한 가중함수 기반 순차 최소거리최대화계획
장준용(Junyong Jang),조수길(Su-gil Cho),이태희(Tae Hee Lee) 대한기계학회 2015 大韓機械學會論文集A Vol.39 No.4
효율적인 최적설계를 위해 공학분야에 도입된 대체모델의 정확성은 표본점에 큰 영향을 받는다. 대체모델의 정확성을 높이는 방법으로 기 추출한 응답을 이용하는 순차실험계획이 제안되었다. 크리깅 대체모델의 상관계수를 가중치로 적용하여 대체모델의 정확성을 향상시킨 연구가 있었으나, 주어진 정보가 부족하거나 상관계수가 잘못 추정된 경우 표본점이 잘못 추출되어 대체모델의 강건성이 저하된다. 본 논문에서는 기존 순차실험계획의 여러 문제점을 제시하고, 이를 해결하기 위한 가중함수 기반 순차 최소거리최대화계획을 제안한다. 제안하는 순차실험계획의 효용성을 수학 함수에 적용하여 기존 순차실험계획들과 비교하여 정확성과 강건성이 향상됨을 예시한다. In order to efficiently optimize the problem involving complex computer codes or computationally expensive simulation, surrogate models are widely used. Because their accuracy significantly depends on sample points, many experimental designs have been proposed. One approach is the sequential design of experiments that consider existing information of responses. In earlier research, the correlation coefficients of the kriging surrogate model are introduced as weight parameters to define the scaled distance between sample points. However, if existing information is incorrect or lacking, new sample points can be misleading. Thus, our goal in this paper is to propose a weight function derived from correlation coefficients to generate new points robustly. To verify the performance of the proposed method, several existing sequential design methods are compared for use as mathematical examples.
시간-변화 동적 응답에 대한 통계적 공간-시간 메타모델링 기법의 비교 연구
장준용(Junyong Jang),이진민(Jin Min Lee),이태희(Tae Hee Lee) 대한기계학회 2010 대한기계학회 춘추학술대회 Vol.2010 No.11
Statistical metamodels have developed with a variety of design optimization techniques in structural engineering fields for the last decade because of efficient design and easy interconnection into design frameworks. However, they have only handled responses with respect to space (design) variables such as size and shape of structures. In this research, statistical space-time metamodeling techniques that can handle time-variant dynamic responses with respect to both space variables and a time variable are compared. The first, we compare spatiotemporal response approach (SRA) and multiple response approach (MRA) from the viewpoint for handling approaches of a time variable. The second, we compare MRA and double-loop MRA from the viewpoint for prediction of responses at time untried points. The last, we compare double-loop MRA and split time region (STR) double-loop MRA from the viewpoint for building time of kriging model.
장준용(Junyong Jang),조수길(Su-gil Cho),이민욱(Minuk Lee),이태희(Tae Hee Lee) 대한기계학회 2011 대한기계학회 춘추학술대회 Vol.2011 No.10
Carrying out optimum design, in general, designer needs to set up ranges of design variables at the beginning. At this point, after we fulfil optimization by using metamodel and design of experiment, we need to modify the ranges of design variables or additional sample point if initial optimum point is located around boundary that designer set arbitrarily. In this study, through extrapolation of metamodel applied to initial design, we quantitatively evaluate accuracy of predicted responses outside of the boundary and propose ranges of extrapolation keeping accuracy without additional sample points. We select krigingmodel as the metamodel which gives Bayesian information and evaluates expanding performance after we examine the nonlinearity according to R-square of response surface model(RSM) through mathematical examples.