• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2014년도 제49차 동계학술대회논문집 22권1호
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• pp.149-151
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• 2014

주의(attention)를 어떻게 할당하는가는 정신물리학뿐만 아니라, 컴퓨터 시각과정을 모델링하는데 중요한 주제 중 하나이다. 기존 연구는 saliency와 같은 활성화 값에 의해서 주의탐사 순위가 결정된다. 본 논문에서는 주의탐사과정을 병렬처리를 통한 활성화 값 추출과정과 순차적 처리를 통한 공간적 전략과정으로 구분하였다. 단서패러다임에 기초한 계산모형을 이용하여, 실제 인간의 수행결과를 AUC와 Levenshtein 척도를 이용하여 비교하였다. Fixation point 비교에서는 인간과 활성화를 기반으로 한 계산모형의 수행은 높은 상관성을 가지고 있었다. 주의궤적 혹은 scanpath 분석에서는 활성화기반 전략보다는 공간적 전략 모형이 더 높은 유사성을 보였다. 이는 주의탐사과정이 병렬처리과정을 통해 얻어진 saliency에 의해서만 결정되는 것이 아니라, 목표물간의 근접성 등의 공간적 전략을 통해 순차적 (sequential) 경로가 생성됨을 의미한다.

• 한국조명전기설비학회지:조명전기설비
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• 제7권3호
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• pp.57-66
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• 1993

본 연구에서는 순차식 게이트구동방식을 사용하여 L, C 공진회로로 링크된 2조의 full-bridge 인버터회로를 병렬제어하는 기법을 제안하고 있다.MOSFET로 구성된 각 인버터는 한 개의 등가스위치 모델로 되어 직렬공진형 등가 half-bridge 인버터회로를 구성하고 있다. 게이트 제어기법으로 각 소자의 구동 주기를 분할 제어함으로서 소자의 직병렬 운전이 가능한 순차식 게이트 구동방식을 사용하고 이에 따른 인버터의 회로동작 모드를 분석하고 해석하였다.시뮬레이션을 통한 회로 해석 결과 각 인버터단과 소자의 전압 및 전류분담이 적절히 이루어지고 있음을 알 수 있었고 안정된 회로동작이 이루어지고 있음을 확인하였다.

• Asian Pacific Journal of Cancer Prevention
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• 제13권5호
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• pp.1863-1867
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• 2012

Background: Maintenance chemotherapy is one strategy pursued in recent years with intent to break through the chemotherapy plateau for advanced non-small cell lung cancer (NSCLC). However, given the toxicity, platinum-based combinations are rarely given for this purpose. We carried out the present prospective study of triplet platinum-based combination sequential chemotherapy in advanced NSCLC to investigate if patients could tolerate and benefit from such intensive treatment. Methods: From Dec 2003 to Dec 2007, 190 stage IIIB and IV NSCLC patients in Sun yat-sen University sequentially received the 3 platinum-based combination (TP-NP-GP) treatment (T: paclitaxol175$mg/m^2$ d1; N: vinorelbine25$mg/m^2$ d1 and 8; G: gemcitabine1$g/m^2$ d1 and 8; P: cisplatin20$mg/m^2$ d1-5; repeated every 3 weeks). Patients were followed up to at least 3 years to obtain survival data. Treatment toxicities and the quality of life (QOL) were assessed during the whole treatment. Results: There were 187 patients evaluable. The TP, NP and GP response rates with sequential use were 42.8% (80/187), 41.1% (65/158) and 28.8% (21/73) respectively. Median survival time was 18.2 months and the 1, 2 and 3 year overall survival (OS) rates were 78.7%, 38.5% and 21.3%. Patients receiving > 6 cycles of chemotherapy had significantly longer OS and TTP (MST 25.3 vs. 14.5 months, TTP 15.1 vs. 9.1 months). The QOL on the whole for the patients was improved after chemotherapy. Conclusions: The sequential chemotherapy strategy with triplet platinum-based combination regimens can improve the survival outcome and the quality of life of advanced non-small cell lung cancer patients.

• Clinical Endoscopy
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• 제56권2호
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• pp.135-142
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• 2023

Endoscopic biliary drainage strategies for managing unresectable malignant hilar biliary obstruction differ in terms of stent type, drainage area, and deployment method. However, the optimal endoscopic drainage strategy remains unclear. Uncovered self-expandable metal stents (SEMS) are the preferred type because of their higher functional success rate, longer time to recurrent biliary obstruction (RBO), and fewer cases of reintervention than plastic stents (PS). Other PS subtypes and covered SEMS, which feature a longer time to RBO than PS, can be removed during reintervention for RBO. Bilateral SEMS placement is associated with a longer time to RBO and a longer survival time than unilateral SEMS placement. Unilateral drainage is acceptable if a drainage volume of greater than 50% of the total liver volume can be achieved. In terms of deployment method, no differences were observed in clinical outcomes between side-by-side (SBS) and stent-in-stent deployment. Simultaneous SBS boasts a shorter procedure time and higher technical success rate than sequential SBS. This review of previous studies aimed to clarify the optimal endoscopic biliary drainage strategy for unresectable malignant hilar biliary obstruction.

• 품질경영학회지
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• 제40권4호
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• pp.431-440
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• 2012

Purpose: In this paper we propose modified Notz designs which are useful to experimenters who want to adopt the sequential experimentation strategy and to estimate second-order regression model with as few experimental points as possible. Methods: We first present the design matrices and design points in two or three dimensional spaces for such small sized second-order designs as small composite, hybrid, and Notz designs. Modified Notz designs are proposed and compared with some response surface designs in terms of the total number of experimental points, the estimation capability criteria such as D- and A-optimality. Results: When sequential experimentation is necessary, the modified Notz designs are recommendable. Conclusion: The result of this paper will be beneficial to experimenters who need to do experiments more efficiently, especially for those who want to reduce the time of experimentation as much as possible to develop cutting-edge products.

• 대한기계학회논문집A
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• 제24권12호
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• pp.3040-3052
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• 2000

For effective construction of second-order response surface models, an efficient quad ratic approximation method is proposed in the context of trust region model management strategy. In the proposed method, although only the linear and quadratic terms are uniquely determined using 2n+1 design points, the two-factor interaction terms are mathematically updated by normalized quasi-Newton formula. In order to show the numerical performance of the proposed approximation method, a sequential approximate optimizer is developed and solves a typical unconstrained optimization problem having 2, 6, 10, 15, 30 and 50 design variables, a gear reducer system design problem and two dynamic response optimization problems with multiple objectives, five objectives for one and two objectives for the other. Finally, their optimization results are compared with those of the CCD or the 50% over-determined D-optimal design combined with the same trust region sequential approximate optimizer. These comparisons show that the proposed method gives more efficient than others.

• 한국농공학회지
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• 제36권2호
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• pp.111-122
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• 1994

In this study, an algorithm which can be applied to the optimum design of simple steel plate girders was developed, and efficient optimization strategies for the solution of algorithm were found out. The optimum design algorithm consists of 3-levels of optimization. In the first and second levels of optimization, the absolute maximum bending moment and shearing force are extracted and in the third level of optimization, the optimum cross section of steel plate girder is determined. For the optimum design of cross section, the objective function is formulated as the total area of cross section and constraints are derived in consideration of the various stresses and the minimum dimension of flange and web based on the part of steel bridge in the Korea standard code of road bridge. Sequential unconstrained minimization technique using the exterior penalty function method(SUMT-EP), sequential linear programming(SLP) and sequential quadratic programming (SQP) are proved to be efficient and robust strategies for the optimum design of simple plate girder cross section. From the reliable point of view, SLP is the most efficient and robust strategy and SQP is the most efficient one from the viewpoint of converguency and computing time.

• Journal of Electrical Engineering and Technology
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• 제7권1호
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• pp.109-114
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• 2012

In this paper, we utilize training strategy of hidden Markov model (HMM) to use in versatile issues such as classification of time-series sequential data such as electric transient disturbance problem in power system. For this, an automatic means of optimizing HMMs would be highly desirable, but it raises important issues: model interpretation and complexity control. With this in mind, we explore the possibility of using genetic algorithm (GA) and harmony search (HS) algorithm for optimizing the HMM. GA is flexible to allow incorporating other methods, such as Baum-Welch, within their cycle. Furthermore, operators that alter the structure of HMMs can be designed to simple structures. HS algorithm with parameter-setting free technique is proper for optimizing the parameters of HMM. HS algorithm is flexible so as to allow the elimination of requiring tedious parameter assigning efforts. In this paper, a sequential data analysis simulation is illustrated, and the optimized-HMMs are evaluated. The optimized HMM was capable of classifying a sequential data set for testing compared with the normal HMM.

• 한국컴퓨터정보학회논문지
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• 제6권2호
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• pp.48-57
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• 2001

퍼지 논리의 추론과정에서 일부의 정보가 무시되어 적절하지 못한 추론 결과를 초래할 수 있다. 한편 신경망은 패턴 처리에는 적합하지만 인간의 지식을 모델링 하기 위해서 필요한 논리적인 추론에는 부적합하다. 그러나 신경망의 변형인 신경 논리망을 이용하면 논리적인 추론이 가능하다. 따라서 본 논문에서는 기존의 신경 논리망을 기반으로 하는 추론네트워크를 확장하여 퍼지 추론 네트워크를 구성한다. 그리고 기존의 추론 네트워크에서 사용되는 전파규칙을 보완하여 적용한다. 퍼지 추론 네트워크상에서 퍼지규칙의 실행부에 해당하는 명제의 믿음 값을 결정하기 위해서는 추론하고자 하는 명제에 연결된 노드들을 탐색해야 한다.

• Structural Engineering and Mechanics
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• 제3권6호
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• pp.529-539
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• 1995

The rigid-plastic yield-line analysis of isotropically reinforced concrete slabs acting in conjunction with torsionally weak supporting beams is developed as the lower-bound form of a linear programming formulation. The analysis is extended to consider geometric variation of chosen yield-line patterns by the technique of sequential linear programming. A strategy is followed of using a fine potential yield-line mesh to identify possible collapse modes, followed by analysis using a coarser, simplified mesh to refine the investigation and for use in conjunction with geometric optimization of the yield-line system. The method is shown to be effective for the analysis of three slabs of varying complexity. The modes detected by the fine and simplified analyses are not always similar but close agreement in load factors has been consistently obtained.