• 제목/요약/키워드: in-exact line search

검색결과 14건 처리시간 0.026초

CONVERGENCE OF DESCENT METHOD WITH NEW LINE SEARCH

  • SHI ZHEN-JUN;SHEN JIE
    • Journal of applied mathematics & informatics
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    • 제20권1_2호
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    • pp.239-254
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    • 2006
  • An efficient descent method for unconstrained optimization problems is line search method in which the step size is required to choose at each iteration after a descent direction is determined. There are many ways to choose the step sizes, such as the exact line search, Armijo line search, Goldstein line search, and Wolfe line search, etc. In this paper we propose a new inexact line search for a general descent method and establish some global convergence properties. This new line search has many advantages comparing with other similar inexact line searches. Moreover, we analyze the global convergence and local convergence rate of some special descent methods with the new line search. Preliminary numerical results show that the new line search is available and efficient in practical computation.

근사 선탐색을 이용한 동적 반응 최적화 (Dynamic response optmization using approximate search)

  • 김민수;최동훈
    • 대한기계학회논문집A
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    • 제22권4호
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    • pp.811-825
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    • 1998
  • An approximate line search is presented for dynamic response optimization with Augmented Lagrange Multiplier(ALM) method. This study empolys the approximate a augmented Lagrangian, which can improve the efficiency of the ALM method, while maintaining the global convergence of the ALM method. Although the approximate augmented Lagragian is composed of only the linearized cost and constraint functions, the quality of this approximation should be good since an approximate penalty term is found to have almost second-order accuracy near the optimum. Typical unconstrained optimization algorithms such as quasi-Newton and conjugate gradient methods are directly used to find exact search directions and a golden section method followed by a cubic polynomial approximation is empolyed for approximate line search since the approximate augmented Lagrangian is a nonlinear function of design variable vector. The numberical performance of the proposed approach is investigated by solving three typical dynamic response optimization problems and comparing the results with those in the literature. This comparison shows that the suggested approach is robust and efficient.

MS-HEMs: An On-line Management System for High-Energy Molecules at ADD and BMDRC in Korea

  • Lee, Sung-Kwang;Cho, Soo-Gyeong;Park, Jae-Sung;Kim, Kwang-Yeon;No, Kyoung-Tae
    • Bulletin of the Korean Chemical Society
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    • 제33권3호
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    • pp.855-861
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    • 2012
  • A pioneering version of an on-line management system for high-energy molecules (MS-HEMs) was developed by the ADD and BMDRC in Korea. The current system can manage the physicochemical and explosive properties of virtual and existing HEMs. The on-line MS-HEMs consist of three main routines: management, calculation, and search. The management routine contains a user-friendly interface to store and manage molecular structures and other properties of the new HEMs. The calculation routine automatically calculates a number of compositional and topological molecular descriptors when a new HEM is stored in the MS-HEMs. Physical properties, such as the heat of formation and density, can also be calculated using group additivity methods. In addition, the calculation routine for the impact sensitivity can be used to obtain the safety nature of new HEMs. The impact sensitivity was estimated in a knowledge-based manner using in-house neural network code. The search routine enables general users to find an exact HEM and its properties by sketching a 2D chemical structure, or to retrieve HEMs and their properties by giving a range of properties. These on-line MS-HEMs are expected be powerful tool for deriving novel promising HEMs.

Advanced Lane Detecting Algorithm for Unmanned Vehicle

  • Moon, Hee-Chang;Lee, Woon-Sung;Kim, Jung-Ha
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.1130-1133
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    • 2003
  • The goal of this research is developing advanced lane detecting algorithm for unmanned vehicle. Previous lane detecting method to bring on error become of the lane loss and noise. Therefore, new algorithm developed to get exact information of lane. This algorithm can be used to AGV(Autonomous Guide Vehicle) and LSWS(Lane Departure Warning System), ACC(Adapted Cruise Control). We used 1/10 scale RC car to embody developed algorithm. A CCD camera is installed on top of vehicle. Images are transmitted to a main computer though wireless video transmitter. A main computer finds information of lane in road image. And it calculates control value of vehicle and transmit these to vehicle. This algorithm can detect in input image marked by 256 gray levels to get exact information of lane. To find the driving direction of vehicle, it search line equation by curve fitting of detected pixel. Finally, author used median filtering method to removal of noise and used characteristic part of road image for advanced of processing time.

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A Development of Safety Management System for Water Lines Using GIS

  • Park, Byoung-Gil
    • Korean Journal of Geomatics
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    • 제1권1호
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    • pp.75-83
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    • 2001
  • Due to the fast industrial growth and unplanned urban underground development in Korea, systematic management for water lines could not be accomplished. Unsystematic water line management has resulted in difficulty in finding the exact location and the age of the lines, which has the potential of leading to a disastrous situation. The objective of this study is a development of safety management system for water lines using GIS. This system is constructed to easily estimate water line deterioration by the geographic output system on it, search for damaged objectives near the surrounding area in a situation of destruction, and offer the emergency information by which one can quickly take action. Also, it is constructed to prevent accidents from occurring during work by presenting underground utilities and states of work.

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Identification of Differentially Expressed Genes by Exposure of Methylmercury in Neuroblastoma Cell Line Using Suppression Subtractive Hybridization (SSH)

  • Kim, Youn-Jung;Ryu, Jae-Chun
    • Molecular & Cellular Toxicology
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    • 제2권1호
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    • pp.60-66
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    • 2006
  • Methylmercury (MeHg), one of the heavy metal compounds, can cause severe damage to the central nervous system in humans. Many reports have shown that MeHg is poisonous to human body through contaminated foods and has released into the environment. Despite many studies on the pathogenesis of MeHg-induced central neuropathy, no useful mechanism of toxicity has been established so far. This study, using of suppression subtractive hybridization (SSH) method, was peformed to identify differentially expressed genes by MeHg in SH-SY5Y human neuroblastoma cell line. We prepared to total RNA from SH-SY5Y cells treated with solvent (DMSO) and $6.25\;{\mu}M\;(IC_{50})$ MeHg and performed forward and reverse SSH. Differentially expressed cDNA clones were screened by dot blot, sequenced and confirmed that individual clones indeed represent differentially expressed genes with real time RT-PCR. These sequences were identified by BLAST homology search to known genes or expressed sequence tags (ESTs). Analysis of these sequences may provide an insight into the biological effects of MeHg in the pathogenesis of neurodegenerative disease and a possibility to develop more efficient and exact monitoring system of heavy metals as ubiquitous environmental pollutants.

문자열 검출을 위한 슬라브 영역 추정 (Slab Region Localization for Text Extraction using SIFT Features)

  • 최종현;최성후;윤종필;구근휘;김상우
    • 전기학회논문지
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    • 제58권5호
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    • pp.1025-1034
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    • 2009
  • In steel making production line, steel slabs are given a unique identification number. This identification number, Slab management number(SMN), gives information about the use of the slab. Identification of SMN has been done by humans for several years, but this is expensive and not accurate and it has been a heavy burden on the workers. Consequently, to improve efficiency, automatic recognition system is desirable. Generally, a recognition system consists of text localization, text extraction, character segmentation, and character recognition. For exact SMN identification, all the stage of the recognition system must be successful. In particular, the text localization is great important stage and difficult to process. However, because of many text-like patterns in a complex background and high fuzziness between the slab and background, directly extracting text region is difficult to process. If the slab region including SMN can be detected precisely, text localization algorithm will be able to be developed on the more simple method and the processing time of the overall recognition system will be reduced. This paper describes about the slab region localization using SIFT(Scale Invariant Feature Transform) features in the image. First, SIFT algorithm is applied the captured background and slab image, then features of two images are matched by Nearest Neighbor(NN) algorithm. However, correct matching rate can be low when two images are matched. Thus, to remove incorrect match between the features of two images, geometric locations of the matched two feature points are used. Finally, search rectangle method is performed in correct matching features, and then the top boundary and side boundaries of the slab region are determined. For this processes, we can reduce search region for extraction of SMN from the slab image. Most cases, to extract text region, search region is heuristically fixed [1][2]. However, the proposed algorithm is more analytic than other algorithms, because the search region is not fixed and the slab region is searched in the whole image. Experimental results show that the proposed algorithm has a good performance.

ASP와 SQL을 연동한 사이버닥터의 지능형 전자진료차트와 데이터처리 (Intelligence Type Electronic Medical Examination Chart and Data Treatment of Cyber Doctor to Interconnect ASP and SQL)

  • 김석수
    • 디지털콘텐츠학회 논문지
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    • 제4권1호
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    • pp.57-66
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    • 2003
  • 본 논문에서는 인터넷 기반에서의 3자(환자, 의사, 약사)간의 상호대화형 원격진료 시스템 구현으로서, 효율적인 진료와 빠른 처리를 위한 전자진료차트 및 자료처리에 관한 내용을 제시하고 있다. 즉, 고가형 시스템, 비호환성 등 기존 원격진료시스템의 문제점을 해결한 저가형이면서, 누구나 참여할 수 있는 웹상에서의 시공간을 초월한 on-line 및 off-line 겸용모드의 지능형 원격진료시스템이다. 데이터베이스는 IIS 4.0 웹서버상에서 ASP와 SQL을 연동한 구현하여 효율적인 자료처리를 위한 시스템 통합과 환자와 의사간의 on-line 상담, 그리고 off-line상에서의 진료와 환자가 지정한 약사로의 처방전 전송 및 조제, 그리고 진료데이터의 저장 및 검색으로 인한 반영구적인 진료데이터저장, 환자 및 의사의 본 진료데이터를 이용한 보다 정확한 진료 및 처방등이 가능하다.

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차량 탑재를 위한 고속 중앙차선 인식 방법 (Fast Center Lane Detection Method for Vehicle Applications)

  • 장광희;곽성우
    • 한국전자통신학회논문지
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    • 제9권6호
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    • pp.649-656
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    • 2014
  • 본 논문에서는 지능형 운전 시스템을 위한 중앙 차선 검출 알고리즘을 제안 한다. 차량의 진행 방향에 있는 가로 한 줄의 색상 정보를 분석하여 중앙 차선에 대한 색상 정보를 얻는다. 이를 기반으로 차선 경계값을 설정하고 형태학적 연산처리와 클러스트링, 그리고 가상 직선화를 통해 중앙 차선을 검출한다. 또한 예상 차선 영역을 설정하여 다음 영상 프레임에서 전체 영상이 아니라 예상 영역에서 차선을 탐색하게 하여 차선 검출 속도를 높였다.

분지한계법을 이용한 양면조립라인 밸런싱 (Two-sided assembly line balancing using a branch-and-bound method)

  • 김여근;이태옥;신태호
    • 대한산업공학회지
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    • 제24권3호
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    • pp.417-429
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    • 1998
  • This paper considers two-sided (left and right side) assembly lines which are often used, especially in assembling large-sized products such as trucks and buses. A large number of exact algorithms and heuristics have been proposed to balance one-sided lines. However, little attention has been paid to balancing two-sided assembly lines. We present an efficient algorithm based on a branch and bound for balancing two-sided assembly lines. The algorithm involves a procedure for generating an enumeration tree. To efficiently search for the near optimal solutions to the problem, assignment rules are used in the method. New and existing bound strategies and dominance rules are else employed. The proposed algorithm can find a near optimal solution by enumerating feasible solutions partially. Extensive computational experiments are carried out to make the performance comparison between the proposed algorithm and existing ones. The computational results show that our algorithm is promising and robust in solution quality.

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