• 제목/요약/키워드: IT Convergency

검색결과 124건 처리시간 0.022초

시스템 식별을 위한 Erlang 함수의 망각 인자를 가진 개선된 RLS 알고리즘 (An Improved New RLS Algorithm with Forgetting Factor of Erlang Function for System Identification)

  • 석진욱;최경삼;이종수;조성원
    • 제어로봇시스템학회논문지
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    • 제5권4호
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    • pp.394-402
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    • 1999
  • In this paper, we present an effective RLS algorithm with forgetting factor of Erlang function for the system identification. In the proposed algorithm, the forgetting factor decreases monotonically in the first stage, and then it increases monotonically in the second stage in contrary to the conventional forgetting factor RLS algorithms. In addition, annealing effect and an asymptotically stability of the proposed algorithm is discussed based on the analysis of convergency property on. Simulation results for the system identification problem indicate the superiority of the proposed algorithm in comparison to the RLS algorithm such as NLMS and Kalman filter based algorithm.

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수학에서의 창의적 태도의 측정도구 개발과 그 적용 (Development and Its Applications of the CAS-K in Mathematics)

  • 김부윤;이지성
    • 한국수학교육학회지시리즈A:수학교육
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    • 제45권1호
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    • pp.25-34
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    • 2006
  • In this paper, we focus on the creative attitude in mathematics as one aspect of mathematical creativity. To measure the creative attitude, we first introduce some prior studies and CAS (Creative Attitude Scale) designed by Noboru Saito in Japan. We develop the CAS-K (Creative Attitude Scale-Korea) including 33 items of 7 factors based on CAS which has 27 items. The factors are fluency, appropriateness, positiveness, independency, concentration, convergency, and accuracy. In CAS-K, it is important to give the information about students' creative attitude for each factor. Thereby, CAS-K can be useful sources of creative attitude to foster mathematical creativity. Rather than the total scores, we emphasize applications and results from CAS-K relating to the 7 factors.

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2차원 박판성형공정해석을 위한 강소성 외연적 유한 요소수식화 (Rigid-Plastic Explicit Finite Element Formulation for Two-Dimensional Analysis of Sheet Metal Processes)

  • 안동규;정동원;양동열
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1993년도 추계학술대회 논문집
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    • pp.206-211
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    • 1993
  • The explicit scheme for finite element analysis of sheet metal forming problems has been widely used for providing practical solution since it improves the convergency problem,memory size and computational time especially for the case of complicated geometry and large element number. In the present work, a basic formulation for rigid-plastic explicit finite element analysis of plain strain sheet metal forming problems has been proposed. The effect of some basic parameters involved in the dynamic analysis has been studied in detail. A direct trial-and-error method is introduced to treat contact and friction. In order to show the validity and effectiveness of the proposed explicit scheme, computation are carried out for cylindrical punch stretching and the computational results are compared with those by the implicit scheme as well as with a commercial code. The proposed rigid-plastic explicit element method can be used as a robust and efficient computational method for analysis of sheet method forming.

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2차원 강소성 유한요소해석에서의 안정성 및 효율성 향상에 관한 연구

  • 박근;양동열
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1993년도 추계학술대회 논문집
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    • pp.195-199
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    • 1993
  • In the analysis of metal forming processes by the finite element method, there are many numerical instabilities such as element locking, hourglass mode, shear locking. These instabilities may have a bad effect upon accuracy and convergence. The present work is concerned with improvement of stability and efficiency in two dimensional rigid-plastic finite element method using various type of elements and numerical integration schemes. AS metal forming examples, upsetting and backward extrusion are taken for comparison among the methods : various element types and numerical integration schemes. comparison is made in terms of stability and efficiency. As a result, it has been shown that the finite element computation is stabilized from the viewpoint of computational time, convergency, and numerical instability.

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국내 공동주택 트렌드 분석 연구 (A Study on Trend Analysis of Domestic Multi-family Housing)

  • 이보라;신연섭;연태경
    • 한국실내디자인학회:학술대회논문집
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    • 한국실내디자인학회 2006년도 춘계학술발표대회 논문집
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    • pp.150-153
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    • 2006
  • The purpose of this study is to analyze the trend of Korean domestic multi-family housing. For that, this study surveyed 139 apartment complex cases which were sold from December 2002 to December 2005. When Hwasung Dongtan apartment complex was sold in 2004, there were a lot of attempts in various quarters, especially in unit planning and eco-friendly design. Accordingly, it is worthy that analyzing the trend before and after of 2004. As a result, the trend has been moving from 'convenient and high class' to 'LOHAS, one-stop living, convergency, and residents' satisfaction' because leasure and well-living have been the purpose of their living. Therefore, we can predict that B.I. and design identity would be more important, and various contents would be created for residents' community and private life.

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Play-Back 서보 시스템의 학습제어 방법 (An Iterative Learning Control of Play-Back Servo Systems)

  • 김광배;안현식;오상록;고명삼
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1989년도 추계학술대회 논문집 학회본부
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    • pp.367-371
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    • 1989
  • As a menas of designing a robust servo system for electrical motor drive system, an iterative learning control method is proposed by employing the structure of the model algorithmic control. A sufficient condition for the convergency is shown, and via simulation for permanent magnet synchronous motor drive system, it is demonstrated 1hat the method yields a 'good performance even in the presence of the external load distrurbances.

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Switched Shunt의 무효전력 민감도를 이용한 조류계산 수렴성 개선 (Improvement of the Power Flow Convergency Using Switched Shunt Reactive Power Sensitivity)

  • 오성균;양민욱;김건중
    • 전기학회논문지
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    • 제61권3호
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    • pp.355-360
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    • 2012
  • It is difficult to converge power flow for the power system planning data. The main cause of power flow diverse is reactive power imbalance. A active power could be adjust by ELD or merit order but a reactive power couldn't dispatch before power flow analysis. The lack of reactive power of power system is cause a inadequate voltage drop This paper suggest new reactive power dispatch algorithm using switched shunt admittance. This algorithm uses reactive power sensitivity called switch shunt jacobian. When proposed algorithm applies to real system data that couldn't be conversed in PSS/E the power flow analysis is converged.

대형 건설프로젝트 현장관리를 위한 복합센서의 필수기능 분석 (Analysis of Essential Function of Composite Sensor for the Ground Work of a Large Construction Project)

  • 조남석;김창원;조대구;조훈희;강경인
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2012년도 춘계 학술논문 발표대회
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    • pp.39-40
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    • 2012
  • Construction IT convergency proposes advanced management abilities of a construction project. Sensing data provided by various sensor technologies can be utilized for diverse management areas. This study analyzes required functions of sensors for implementing time, cost, safety and quality management, focusing on the ground works including excavation, pipe installation, retaining wall etc. Therefore, this study first generates essential management areas, analyzes cutting-edge sensor technologies appropriated for the areas, and finally proposes a matrix system that represents relationships between the management areas and sensor technologies, The proposed system is expected to reinforce construction management abilities by integrating sensor technologies.

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Lattice 필터에 의한 OFDM 신호의 채널 등화 특성 (Channel Equalization Characteristic of Lattice Filter in OFDM Signal)

  • 조상현;이우재;신위재;주창복
    • 융합신호처리학회 학술대회논문집
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    • 한국신호처리시스템학회 2001년도 하계 학술대회 논문집(KISPS SUMMER CONFERENCE 2001
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    • pp.45-48
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    • 2001
  • 본 논문에서는 OFDM 시스템에 있어서 심블간 간섭을 일으키는 채널에 대해 lattice 필터를 사용한 등화기의 등화 특성을 검토하였다. Lattice 괼터를 사용한 등화기는 다른 등화기와 비교해서 단수마다의 직교화 효과에 의해, 탭 수가 작아도 수렴이 빠르고 등화 오차를 작게 할 수 있는 특징이 있다. 본 논문에서는 Lattice 필터를 사용한 등화기 필터 계수의 수렴성과 정적인 BER특성을 컴퓨터 시뮬레이션에 의해 해석하고 Transversal 필터 방식에 비해서 우수한 보상 방식인 것을 보인다.

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순간가열(瞬間加熱)된 Strip의 과도적열응력해석(過渡的熱應力解析) (Thermal Stress Analysis in the Vicinity of Butt Welded Joiny of a Strip)

  • 박종은;김효철
    • 대한조선학회지
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    • 제10권1호
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    • pp.15-20
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    • 1973
  • In this paper, it is desired to show a simplified analytical method in estimating the thermal stresses in the heat affected zone of butt welded joint. A finite strip as shown in Fig.1 is taken as a analytical model for stress analysis. Expressing the temperature distributions by Fourier series, the thermal stresses are obtained. From the numerical sample calculation, the following results can be obtained. (1) Thermal stresses can be estimated by the sujected method. (2) The stress component, which is parallel to the weld direction is the largest stress component in major part of the strip. (3) In obtaining a stress component for the engineering purpose, length of the strip can be treated as five times of the thickness with same degree of convergency.

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