• Title/Summary/Keyword: conventional method

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Improving Real-Time Efficiency of Case Retrieving Process for Case-Based Reasoning

  • Park, Yoon-Joo
    • Asia pacific journal of information systems
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    • v.25 no.4
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    • pp.626-641
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    • 2015
  • Conventional case-based reasoning (CBR) does not perform efficiently for high-volume datasets because of case retrieval time. To overcome this problem, previous research suggested clustering a case base into several small groups and retrieving neighbors within a corresponding group to a target case. However, this approach generally produces less accurate predictive performance than the conventional CBR. This paper proposes a new case-based reasoning method called the clustering-merging CBR (CM-CBR). The CM-CBR method dynamically indexes a search pool to retrieve neighbors considering the distance between a target case and the centroid of a corresponding cluster. This method is applied to three real-life medical datasets. Results show that the proposed CM-CBR method produces similar or better predictive performance than the conventional CBR and clustering-CBR methods in numerous cases with significantly less computational cost.

A study on the speed control of ship propulsion induction motor using improved AFE rectifier

  • HUR, Jae-Jung
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.56 no.1
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    • pp.71-81
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    • 2020
  • This paper proposes a possibility of using active front-end rectifier with the SVPWM method for induction motor speed control, which is applicable to small electric propulsion boats. The proposed method can produce a more precise sinusoidal input current waveform and a higher power factor than conventional methods. Its speed, torque, input current, DC voltage, and load current control performance are similar to or better than those of conventional methods. Through computer simulations using the PSIM program, the validity of the proposed method was verified by comparing and analyzing the characteristics of the conventional methods and the proposed method.

A new Driving Algorithm Design and Implementation for High Efficiency and High Image Quality in PDP (PDP 고효율 고화질 구동 알고리즘 설계 및 FPGA 구현)

  • Cha, Soo-Ik;Lee, Dong-Ho
    • Proceedings of the KIEE Conference
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    • 2005.05a
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    • pp.152-154
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    • 2005
  • This paper proposes the new subfield method to erase reverse gray levels and low gray level contour in AC plasma display panel(PDP). In the conventional method, it is supposed that output luminance levels of a PDP increase regularly. But actual output luminance levels of a PDP increase irregularly. Therefore, conventional methods are unable to effectively reduce low gray-level contours and reverse gray levels. Accordingly, a new subfield method is applied to improve the low gray-level expression in PDP. Conclusively this paper clear proof that a new subfield method can suppress low gray-level contours and reverse gray levels more effectively than conventional methods.

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Kalman filter Method and the Conventional Method for the Bias Error Reduction of INS Vertical Channel (관성 항해 시스템 수직 찬넬의 Bias Error 감소에의 Kalman Filter 방법과 재래식 방법의 응용 비교)

  • Ha, In-Jung;Kim, Yeong-Gyun;Choe, Gye-Geun
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.19 no.2
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    • pp.23-30
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    • 1982
  • In this paper, two methods (Kalman filter and Conventional) are investigated to reduce the bias error in the INS (Intertial Navigation System) vertical channel. The schemes by these methods show better performance (estimation error and response) than the others commonly used. Comparison results show that the scheme by Kalman filter method gives much better performance than the Conventional method.

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A study on integrated guidance scheme for guided weapon system (유도무기를 위한 통합된 유도기법에 관한 연구)

  • 김병수;한형석;이장규;박성희;이재명;김삼수
    • 제어로봇시스템학회:학술대회논문집
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    • 1992.10a
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    • pp.590-595
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    • 1992
  • An integrated guidance scheme for guided weapon system is described in this paper. Against conventional guidance methods, this method combines an autopilot and a guidance law. The controller is designed using LQ regulator whose performance index is different from other optimal guidance laws. Since dynamics of the system is considered in the derivation, the controller performance is improved. By simulation, the suggested method shows better performance in minimum distance sense than conventional guidance schemes such as Bang Bang guidance or Pursuit Guidance. Since the suggested method provides smooth rudder deflection in contrast to the conventional method, the load on a energy source of the system can be greatly lessened.

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Development of a Smooth Colon Surface Restoration Method for Electronic Colon Cleansing (전자적 장세척을 위한 부드러운 장표면 복원 방법 개발)

  • Kim, Seung-Hwan;Kim, Dong-Sung
    • Journal of Biomedical Engineering Research
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    • v.32 no.3
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    • pp.251-256
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    • 2011
  • Virtual colonoscopy is favored over conventional colonoscopy because its non-invasive procedure can avoid complications that may happen in a conventional approach and because it can cleanse colon electronically instead of uncomfortable conventional colon cleansing. Electronic Colon Cleansing(ECC) has to deal with not only removing tagged fecal material but also recovering Partial Volume Effect(PVE) due to tagging material. This paper proposes an ECC method restoring inherent natural PVE while previous approaches focused only on reducing PVE due to tagged fecal material. The proposed method reduces PVE using 3-dimensional adaptive density correction and then replaces tagged fecal material into air. Next, it generates natural PVE for the replaced air adjacent to soft tissue and finally makes smooth transition of gray values for soft tissue adjacent to the replaced air. The proposed method applied to eleven patient data, and showed promising results.

Performance Enhancement of Trellis Coded Mary PSK using Minimum Hamming Distance (최소해밍거리를 이용한 트렐리스 부호화된 M- ray PSK의 성능 향상)

  • 은도현;조훈상;이순흠
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.3
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    • pp.417-424
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    • 2001
  • This paper proposes new symbol mapping method that can enhance the performance of trellis coded M-ary PSK compared with conventional symbol mapping methods in AWGN environment. Since the basic criteria of TCM design is Maximum Euclidean distance in AWGN, conventional symbol mapping method keep this basic criteria. In this paper, proposed new symbol mapping method uses both Euclidean distance and Hamming distance to design, while conventional methods make use of only optimal Euclidean distance. New symbol mapping method show the better BER performance than the other through computer simulation and error equations.

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Introduction of Conventional Stress Analysis Method based on Kowalski's Formula at Internal Thread Undercut

  • Yoon, Jaehuy;Kang, Youngsu;Lee, Inchul;Park, Sangjoon
    • International Journal of Aerospace System Engineering
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    • v.2 no.2
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    • pp.54-57
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    • 2015
  • The purpose of this paper is to provide the method of conventional stress analysis for a pressurized hydraulic cylinder with internal thread undercut. In the case of hydraulic cylinder with thread undercut, several loads and stresses occur during operating. So, the thread undercut can be most critical section has to be considered in detail for strength check. In this paper, the conventional stress analysis method at internal thread undercut of hydraulic cylinder based on Kowalski's formula is introduced. The method is verified by comparing to FEM analysis results using ANSYS.

A Fast and Adaptive Feature Extraction Method for Textured Image Segmentation (Texture 영상 분할을 위한 고속 적응 특징 추출 방법)

  • 이정환;김성대
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.16 no.12
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    • pp.1249-1265
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    • 1991
  • In this paper, a fast and adaptive feature extraction algorithm for textured image segmentation is proposed. First, a conventional algorithm to extract the statistical texture features are described and we obtain the recursive equations from that conventional method and it is used for extraction of sevaral texture features. And also we propose the adaptive algorithm which extract the texture features. To evaluate the performance of proposed algorithm, we apply the proposed method to artificial texture images. From the results of computer simulation, the proposed method is superior to the conventional one.

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Tree aging observation of XLPE by image processing (화상처리에 의한 XLPE의 트리열화관측)

  • 임장섭;김태성;길촌승
    • Electrical & Electronic Materials
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    • v.8 no.5
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    • pp.551-557
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    • 1995
  • For the observation of treeing, a visual measurement with an optical microscope has been used to explain breakdown mechanism in high-voltage systems. The conventional directed visual method of tree aging observation is difficult to measure in short time processing, and it is impossible to analyze on tree degradation area, progressed direction, tree pattern, etc. By using an image processing technique, the tree features which appear immediately after the tree initiation as well as changes in the configuration of the tree can be easily measured and observed than using the conventional visual methods. In this paper, we have developed a tree observating system by using image processing for tree growth, degradation area and other treeing progress. As an experimental result, it can be concluded that the image processing method is a more effective alternative than directed visual observation method. As a matter of fact, it is possible to record the image of tree propagation immediately after its first appearance and explain the characteristics of tree growth froth the computer processing image.

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