• Title/Summary/Keyword: generality

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A New Correction Algorithm of Servo Track Writing Error in High-Density Disk Drives (고밀도 디스크 드라이브의 서보트랙 기록오차 보정 알고리즘)

  • 강창익;김창환
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.4
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    • pp.284-295
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    • 2003
  • The servo tracks of disk drives are constructed at the time of manufacture with the equipment of servo track writer. Because of the imperfection of servo track writer, disk vibrations and head fluctuations during servo track writing process, the constructed servo tracks might deviate from perfect circles and take eccentric shapes. The servo track writing error should be corrected because it might cause interference with adjacent tracks and irrecoverable operation error of disk drives. The servo track writing error is repeated every disk rotation and so is periodic time function. In this paper, we propose a new correction algorithm of servo track writing error based on iterative teaming approach. Our correction algorithm can learn iteratively the servo track writing error as accurately as is desired. Furthermore, our algorithm is robust to system model errors, is computationally simple, and has fast convergence rate. In order to demonstrate the generality and practical use of our work, we present the convergence analysis of our correction algorithm and some simulation results.

Development of a General Purpose PID Motion Controller Using a Field Programmable Gate Array

  • Kim, Sung-Su;Jung, Seul
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.360-365
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    • 2003
  • In this paper, we have developed a general purpose motion controller using an FPGA(Field Programmable Gate Array). The multi-PID controllers on a single chip are implemented as a system-on-chip for multi-axis motion control. We also develop a PC GUI for an efficient interface control. Comparing with the commercial motion controller LM 629 it has multi-independent PID controllers so that it has several advantages such as space effectiveness, low cost and lower power consumption. In order to test the performance of the proposed controller, robot finger is controlled. The robot finger has three fingers with 2 joints each. Finger movements show that position tracking was very effective. Another experiment of balancing an inverted pendulum on a cart has been conducted to show the generality of the proposed FPGA PID controller. The controller has well maintained the balance of the pendulum.

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Optimal Displacement Control of Shear Wall Structure using Sensitivity Analysis Technique (감도해석기법을 이용한 전단벽 구조물의 최적변위제어)

  • Lee Han-Joo;Jung Sung-Jin;Kim Ho-Soo
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2005.04a
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    • pp.121-128
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    • 2005
  • This study presents an effective stiffness-based optimal technique to control quantitatively lateral drift for shear wall structures subject to lateral loads. To this end the displacement sensitivity depending on behavior characteristics of shear wall structures is established. Also, the approximation concept that can preserve the generality of the mathematical programming and can efficiently solve large scale problems is introduced. Resizing sections in the stiffness-based optimal design are assumed to be uniformly varying in size and the technique of member grouping is considered for the improvement of construction efficiency Two types of 11-story shear wall structures are presented to illustrate the features of the quantitative lateral drift control technique proposed in this study.

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Recognition of Printed and Handwritten Numerals Using Multiple Features and Modularized Neural Networks (다중 특징과 모듈화된 신경회로망을 이용한 인쇄 및 필기체 혼용 숫자 인식)

  • 류강수;김우태;진성일
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.32B no.10
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    • pp.1347-1357
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    • 1995
  • In this paper, we describe a modularized neuroclassifier for enhancing the recognition accuracy of mixed printed and handwritten numerals. This classifier combines four modularized subclassifiers using multi-layer perceptron module. The input of each subclassifier is comprised of a group of specialized feature sets. On applying this method to combining several subclassifiers for unconstrained handwritten numerals, the experimental result shows that the performance of individual subclassifier can be improved. In winner-take-all voting method, the result of subclassifier having the highest RF value is selected as the output. The generality of this classifier is tested with 1,080 printed and 3,000 handwritten numerals that was not shown in training the neural networks. Experimental results show 98.2% recognition rate. The typical recognition test with a threshold value(RF=1.5) has shown 97% recognition, 1% substitution and 2% rejection rates.

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A Design of the General-Purpose Fuzzy Hardware (범용의 퍼지 하드웨어 설계)

  • ;;;Zeungnam Bien
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.31B no.7
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    • pp.149-158
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    • 1994
  • Recently the fuzzy control is widely used as a tool for constructing automatic control systems which can replace the manual operation of large-scale nonlinear plants. In most applications of the fuzzy control however it is hard to meet the requirement of the operation time. In some real-time control the fuzzy control scheme requires too much computing time for fuzzification inference and defuzzification. To reduce the computing time there may be two alternatives the development of a new operation algorithm and the design of high-speed fuzzy hardware. In this paper to solve the problem of reducing the fuzzy operation time we propose a new high-speed fuzzy hardware scheme which has merits of its generality and extensibility. Finally we verify the proposed fuzzy hardware.

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Wavelet based system identification for a nonlinear experimental model

  • Li, Luyu;Qin, Han;Niu, Yun
    • Smart Structures and Systems
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    • v.20 no.4
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    • pp.415-426
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    • 2017
  • Traditional experimental verification for nonlinear system identification often faces the problem of experiment model repeatability. In our research, a steel frame experimental model is developed to imitate the behavior of a single story steel frame under horizontal excitation. Two adjustable rotational dampers are used to simulate the plastic hinge effect of the damaged beam-column joint. This model is suggested as a benchmark model for nonlinear dynamics study. Since the nonlinear form provided by the damper is unknown, a Morlet wavelet based method is introduced to identify the mathematical model of this structure under different damping cases. After the model identification, earthquake excitation tests are carried out to verify the generality of the identified model. The results show the extensive applicability and effectiveness of the identification method.

A Study on Consumer perception about seafood of Hebei Spirit Oil Spill Incident Area (유류사고 피해지역 수산물에 대한 소비자 인식 연구)

  • KIM, Jong-Hwa
    • Journal of Fisheries and Marine Sciences Education
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    • v.27 no.6
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    • pp.1693-1703
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    • 2015
  • This study is aimed to retain objectivity and generality against consumer perception about seafood of Hebei Spirit oil spill incident area, and analyze gap of consumer perception in according to confidence level of seafood using ordinal logit model. As results, This article have three implications. First, Consumer don't have high confidence level in comparison with previous research. Second, It is important to retain confidence of quality for purchasing seafood of oil spill incident area. Third, Consumer perception is improved positively against seafood of oil spill area. But This study has limits that don't take regional opinion and situation into account.

Numerical Simulation on Turbulent Shear Flows over Surface-Mounted Obstacles (표면에 부착된 장애물 주위의 난류전단유동에 관한 수치해석)

  • Myeong, Hyeon-Guk
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.20 no.8
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    • pp.2593-2600
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    • 1996
  • A modified k-$\varepsilon$ turbulence model having a generality is proposed in the present study, in which the constant $C_{\varepsilon2}$in the $\varepsilon$-equation is simply changed as a functional form of a new parameter both satisfying the tensor invariant condition and representing the extra straining effect on complex shear flows. With this model turbulent shear flows over two-dimensional obstacles placed in a channel are numerically studied for different blockage ratios and aspect ratios. Comparing with the available experimental data, the predicted results with the present model provide definite improvements over the standard model's results and work fairly well with the experimental data on the size of the recirculation zone, as well as mean velocity, wall static pressure, turbulent kinetic energy and Reynolds stresses.

The Development of Disaster Prevention Information System Using Internet GIS (Internet GIS를 이용한 방재정보시스템 구축)

  • Yeo, Woon-Ki;Jang, Kyung-Soo;Jeon, Ji-Young;Jee, Hong-Kee
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.620-623
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    • 2007
  • The purpose of this study is developing a disaster prevention information system using Internet GIS to manage disaster information more efficiently and timely. This system has good potential with environment of Internet which has appropriate characteristics of rapidity, wide reach, generality, cost effectivity for disaster management. With this system, general user can easily retrieve disaster information with visuality such as maps. graphs, and texts just by using web browsers. Hence the need of developing Internet GIS system for disaster prevention is growing in these days.

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Expansible and Reconfigurable Neuro Informatics Engine : ERNIE (대규모 확장이 가능한 범용 신경회로망 : ERNIE)

  • 김영주;정제교;동성수;이종호
    • Proceedings of the IEEK Conference
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    • 2003.07d
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    • pp.1263-1266
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    • 2003
  • One of the hardest problems in implementation of digital neural network are extension of synapses and programmability for relocating neurons. This paper Proposes a new hardware structure to solve these problems. The proposed structure can reconfigure network connections without alteration of basic design, and extend number of synapses attached to one neuron. Also, it is possible to extend the number of neurons and layers by connecting many MPUs(Modular Processing Unit). Generality and extensibility are verified by composing various kinds of Perceptorn and Kohonen networks using the architecture proposed in this paper and the verification performances compares well with HDL simulation results as well as the results of C modelling.

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