• 제목/요약/키워드: rack system

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센서 노드를 위한 플래시 메모리 저장 시스템에 대한 고찰 (Survey on Flash Memory based Storage System for Sensor Nodes)

  • 송준영;이기혁;한형진;최원철;한경훈;한지연;손기락
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 2007년도 가을 학술발표논문집 Vol.34 No.2 (C)
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    • pp.23-28
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    • 2007
  • 본 논문에서는 현재 많은 분야에 적용되어 데이터 수집을 위해 사용되는 센서 노드들의 데이터 저장을 위한 플래시 메모리를 기반으로 한 저장 시스템들을 비교해 보고 각각의 특징과 취약점을 비교 분석한다. 그리고 대용량 플래시 메모리 기반 저장시스템을 위한 개발 방안에 대한 앞으로 나아갈 방향을 제시한다.

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용수로 분수문 개폐장치 개발 (Development of Devices of the Diversion Gate in Irrigation Canal)

  • 전종길;김경원;이인복;천만복
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2003년도 학술발표논문집
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    • pp.223-226
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    • 2003
  • Devices of diversion gate used at irrigation canal, as a irrigation structures of agriculture, have shown serious problems such as corrosion, defect, inconvenience of operation, etc. Accordingly, handy devices of diversion gate have been developed and then tested in the laboratory. The operating types of the prototype were a rack-and-pinion type, an improved screw type that only gate plate was moved up and down while the screw axis was unmoved, and a remote control type which can be controlled from 50m away using a remote control system. Those 3 types were developed, and the improved screw type was shown the best operation through the laboratory tests.

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세종 자격루의 경점보시 시스템의 복원 (ht-Watch Time-Annunciating Systems for the King Sejong's Striking Clepsydra)

  • 남문현
    • 대한전기학회논문지
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    • 제38권12호
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    • pp.1022-1032
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    • 1989
  • King Sejong's Striking Clepsydra was an elaborate timekeeping and annunciating system incorporating biological automata capable of annunciating hours, intervals and night-watches based on Shou-shih calindrical systems automatically. In this paper the author has studied the original manuscripts on the Striking Clepsydra [Sejong sillock, 65: 1a-3b ff` 16th year, 7th month(1434)] from the technical point of view undertaking a close analysis of this monumental clock and aiming to our modern understanding of the full degree of delicate mechanisms and sophisticated controls built into the night-watch and division announcing clockwork(jackwork). Based on the input/output model, timekeeping, ball-rack, ball-relay, and audible time-indicating mechanisms were synthesized reconstructing night-watch annunciating systems. It revealed that the night-watch and division announcing processes were entirely renewed automatically. Historical and philological data concerning the improvements of the proposed model were discussed.

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Development of a shared remote control robot for aerial work in nuclear power plants

  • Shin, Hocheol;Jung, Seung Ho;Choi, You Rack;Kim, ChangHoi
    • Nuclear Engineering and Technology
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    • 제50권4호
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    • pp.613-618
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    • 2018
  • We are developing a shared remote control mobile robot for aerial work in nuclear power plants (NPPs); a robot consists of a mobile platform, a telescopic mast, and a dual-arm slave with a working tool. It is used at a high location operating the manual operation mechanism of a fuel changer of a heavy water NPP. The robot system can cut/weld a pipe remotely in the case of an emergency or during the dismantling of the NPP. Owing to the challenging control mission considering limited human operator cognitive capability, some remote tasks require a shared control scheme, which demands systematic software design and integration. Therefore, we designed the architecture of the software systematically.

시계열모델을 이용한 하수처리장 유입수 성상 예측 (Forecast of Influent Characteristics in Wastewater Treatment Plant with Time Series Model)

  • 김병군;문용택;김홍석;김종락
    • 상하수도학회지
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    • 제21권6호
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    • pp.701-707
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    • 2007
  • The information on the incoming load to wastewater treatment plants is not often available to apply to evaluate effects of control actions on the field plant. In this study, a time series model was developed to forecast influent flow rate, BOD, COD, SS, TN and TP concentrations using field operating data. The developed time series model could predict 1 day ahead forecasting results accurately. The coefficient of determination between measured data and 1 day ahead forecasting results has a range from 0.8898 to 0.9971. So, the corelation is relatively high. We made forecasting program based on the time series model developed and hope that the program will assist the operators in the stable operation in wastewater treatment plants.

제한된 구동기 용량을 갖는 선형 시스템의 스케듈링 $H_{\infty}$ 제어기 설계 (Design of Scheduled $H_{\infty}$ Control for Linear Systems with Limited Actuator Capacity)

  • 송용희;김진훈
    • 대한전기학회논문지:시스템및제어부문D
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    • 제53권9호
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    • pp.622-629
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    • 2004
  • In practical control systems, the capacity of actuators is limited and this degrades the system performances and it is often a source of instability. To use full capacity of actuators, we adopt the gain scheduled control permitting the over saturation in controls. The basic idea of gain scheduled control is to use a higher gain control when the state variables are smaller and a lower gain control when the state variables are larger. First, we derive a constant H control and a reachable set while satisfying the degree of over saturation. Next, we divide this set into nested subsets and find $H_{\infty}$ controls at rack subsets while satisfying the degree of over saturation. Finally, the control gain is applied according to the status of states. Note that all procedures are done by solving linear matrix inequalities(LMI). Finally, we show the validity and applicability of our proposed control using the simulations of a six-story building subjected to the earthquake excitation.

효율적인 병원전산시스템 운영을 위한 KMS 적용에 관한 연구 (A Study on KMS adapt ways to hospital computer system effective operation)

  • 윤영기;박구락;김진묵
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2014년도 추계 종합학술대회 논문집
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    • pp.5-6
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    • 2014
  • 본 논문은 전국적으로 병원 전산시스템을 운영하는 근로자의 근무 조건들과 애로사항, 병원 전산시스템의 운영 특징들에 대해 조사하였다. 대전지역 보훈병원 전산 근로자들을 대상으로 설문조사한 결과 기술적, 환경적, 동료관계적 특징들에 대해서 파악하게 되었고, 이를 해결할 수 있는 방법으로 지식관리시스템 기술을 도입함으로써 효율적인 운영이 가능하다. 향후 연구를 확대해 대전지역 보훈병원뿐만 아니라 충남지역 일반병원까지 제안 연구기법을 적용함으로써 지식관리시스템 기술을 도입함으로써 병원 전산시스템의 운영 및 관리에 효율성을 높일 수 있음을 보인다.

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현가장치 기구정역학 시험에 의한 차량동역학 모델링 및 시험검증 (Vehicle Dynamics Modeling and Correlation Using the Kinematic and Compliance Test of the Suspension)

  • 김상섭;정홍규
    • 한국자동차공학회논문집
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    • 제13권1호
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    • pp.109-118
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    • 2005
  • A functional suspension model is proposed as a kinematic describing function of the suspension that represents the relative wheel displacement in polynomial form in terms of the vertical displacement of the wheel center and steering rack displacement. The relative velocity and acceleration of the wheel is represented in terms of first and second derivatives of the kinematic describing function. The system equations of motion for the full vehicle dynamic model are systematically derived by using velocity transformation method of multi-body dynamics. The comparison of field test results and simulation results of the ADAMS/Car demonstrates the validity of the proposed functional suspension modeling method. This model is suitable for real-time vehicle dynamics analysis.

파워스티어링 기어박스 특성을 이용한 중립 조향감의 향상 (Improvement of on Center Steer Feel by Using Power Steering Gear Box Characteristics)

  • 이병림;이재응
    • 한국자동차공학회논문집
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    • 제10권6호
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    • pp.202-208
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    • 2002
  • Ball k nut type steering gear box has disadvantages on on-center range as compared with rack & pinion type because of many linkages. In this study, a technique which can improve the on-center loose feel is introduced. The improvement can be obtained by putting simple devices on steering gear box valve body which can change the stiffness of steering gear on on-center handling range. Analysis and test of the vehicle with improved steering system are performed.

6-시그마 기법을 이용한 고속자동피치가변장치 메커니즘 설계 (Mechanism Design of High Speed Automated Pitch Variation Unit by using 6-Sigma Method)

  • 이진환;원윤재;이혁
    • 반도체디스플레이기술학회지
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    • 제7권4호
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    • pp.23-28
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    • 2008
  • A high speed automated pitch variation unit (HAPU) related to semiconductor category sorting movement of the test handler system was developed. In the design process, 'DMADOV' step of 6-Sigma method has been applied. The design result for the desirable pitch variation was a 3:1 reduction rack-pinion and a linkage which are operated by servomotors. The realization and reliability of the mechanism was obtained at the design stage by FEM analysis, and by robust design using Taguchi orthogonal array against weight and deformation. Finally, the validity of the high speed variation mechanism was confirmed via inspection using a high speed camera while performing pitch variation.

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