• 제목/요약/키워드: System Base

검색결과 7,089건 처리시간 0.03초

Constraint Algorithm in Double-Base Number System for High Speed A/D Converters

  • Nguyen, Minh Son;Kim, Man-Ho;Kim, Jong-Soo
    • Journal of Electrical Engineering and Technology
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    • 제3권3호
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    • pp.430-435
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    • 2008
  • In the paper, an algorithm called a Constraint algorithm is proposed to solve the fan-in problem occurred in ADC encoding circuits. The Flash ADC architecture uses a double-base number system (DBNS). The DBNS has known to represent the multi-dimensional logarithmic number system (MDLNS) used for implementing the multiplier accumulator architecture of FIR filter in digital signal processing (DSP) applications. The authors use the DBNS with the base 2 and 3 to represent binary output of ADC. A symmetric map is analyzed first, and then asymmetric map is followed to provide addition read DBNS to DSP circuitry. The simulation results are shown for the Double-Base Integer Encoder (DBIE) of the 6-bit ADC to demonstrate an effectiveness of the Constraint algorithm, using $0.18{\mu}\;m$ CMOS technology. The DBIE’s processing speed of the ADC is fast compared to the FAT tree encoder circuit by 0.95 GHz.

베이스 가진을 받는 능동자기베어링 시스템에서 Filtered-x LMS 알고리듬을 이용한 가속도 앞먹임 제어 (Acceleration Feedforward Control in Active Magnetic Bearing System Subject to Base Motion by Filtered-x LMS Algorithm)

  • 강민식
    • 대한기계학회논문집A
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    • 제27권10호
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    • pp.1712-1719
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    • 2003
  • This paper concerns on application of active magnetic bearing(AMB) system to levitate the elevation axis of an electro-optical sight mounted on moving vehicles. In such a system, it is desirable to retain the elevation axis within the predetermined air-gap while the vehicle is moving. An optimal base acceleration feedforward control is proposed to reduce the base motion response. In the consideration of the uncertainty of the system model, a filtered-x least-mean-square(FXLMS) algorithm is used to estimate the frequency response function of the feedforward control which cancels base motions. The frequency response function is fitted to an optimal feedforward control. Experimental results demonstrate that the proposed control reduces the air-gap deviation to 27.7% that by feedback control alone.

Smart passive control of buildings with higher redundancy and robustness using base-isolation and inter-connection

  • Murase, Mitsuru;Tsuji, Masaaki;Takewaki, Izuru
    • Earthquakes and Structures
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    • 제4권6호
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    • pp.649-670
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    • 2013
  • It is known that a base-isolated building exhibits a large response to a long-duration, long-period wave and an inter-connected system without base-isolation shows a large response to a pulse-type wave. To compensate for each deficiency, a new hybrid passive control system is investigated in which a base-isolated building is connected to another building (free wall) with oil dampers. It is demonstrated that the present hybrid passive control system is effective both for pulse-type ground motions and long-duration and long-period ground motions and has high redundancy and robustness for a broad range of disturbances.

지능공작기계 지식구조의 규칙베이스 구축 (Constructing Rule Base of knowledge structure for Intelligent Machine Tools)

  • 이승우;김동훈;임선종;송준엽;이화기
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 추계학술대회 논문집
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    • pp.954-957
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    • 2005
  • In order to implement Artificial Intelligence, various technologies have been widely used. Artificial Intelligence is applied for many industrial product and machine tools are the center of manufacturing devices in intelligent manufacturing system. The purpose of this paper is to present the construction of Rule Base for knowledge structure that is applicable to machine tools. This system is that decision whether to act in accordance with machine status is support system. It constructs Rule Base of knowledge used of machine toots. The constructed Rule Base facilitates the effective operation and control of machine tools and will provide a systematic way to integrate the expert's knowledge that will apply Intelligent Machine Tools.

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Seismic isolation performance sensitivity to potential deviations from design values

  • Alhan, Cenk;Hisman, Kemal
    • Smart Structures and Systems
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    • 제18권2호
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    • pp.293-315
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    • 2016
  • Seismic isolation is often used in protecting mission-critical structures including hospitals, data centers, telecommunication buildings, etc. Such structures typically house vibration-sensitive equipment which has to provide continued service but may fail in case sustained accelerations during earthquakes exceed threshold limit values. Thus, peak floor acceleration is one of the two main parameters that control the design of such structures while the other one is peak base displacement since the overall safety of the structure depends on the safety of the isolation system. And in case peak base displacement exceeds the design base displacement during an earthquake, rupture and/or buckling of isolators as well as bumping against stops around the seismic gap may occur. Therefore, obtaining accurate peak floor accelerations and peak base displacement is vital. However, although nominal design values for isolation system and superstructure parameters are calculated in order to meet target peak design base displacement and peak floor accelerations, their actual values may potentially deviate from these nominal design values. In this study, the sensitivity of the seismic performance of structures equipped with linear and nonlinear seismic isolation systems to the aforementioned potential deviations is assessed in the context of a benchmark shear building under different earthquake records with near-fault and far-fault characteristics. The results put forth the degree of sensitivity of peak top floor acceleration and peak base displacement to superstructure parameters including mass, stiffness, and damping and isolation system parameters including stiffness, damping, yield strength, yield displacement, and post-yield to pre-yield stiffness ratio.

SDR 시스템을 위한 MPI 기반 WiMAX 기지국의 구현 (Implementation of MPI-based WiMAX Base Station for SDR System)

  • 안치영;김효한;최승원
    • 디지털산업정보학회논문지
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    • 제9권4호
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    • pp.59-67
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    • 2013
  • Compared to the conventional Hardware-oriented base stations, Software Defined Radio (SDR)-based base station provides various advantages especially in flexibility and expandability. It enables the multimode capability required in 4th-generation (4G) environment which aims at a convergence network of various kinds of communication standards. However, since a single base station processes all data required in various multiple waveforms, the SDR base station faces a problem of data processing speed. In this paper, we propose a new concept of SDR base station system which adopts a parallel processing technology of clustering environment. We implemented a WiMAX system with SDR concept which adopts the Message Passing Interface (MPI) technology which enables the speed-up operations. In order to maximize the efficiency of parallel processing in signal processing, we analyze how the algorithm at each of modules is related to data to be processed. Through the implemented system, we show a drastic improvement in operation time due to parallel processing using the proposed MPI technology. In addition, we demonstrate a feasibility of SDR system for 4G or even beyond-4G as well.

교량의 예비설계를 위한 전문가 시스템의 개발 (Development of Expert System for a Preliminary Bridge Design)

  • 최창근;최인혁
    • 대한토목학회논문집
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    • 제12권1호
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    • pp.9-17
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    • 1992
  • 본 논문에서는 교량의 예비설계 단계중에서 상부구조 형식의 선정에 대한 전문가 시스템을 구축하는 것을 나타낸다. 본 시스템을 구축하기 위한 도구로는 전진추론방식 및 생산시스템으로 지식표현되는 전문가 시스템 개발용 도구인 K-CLIPS가 이용되었으며, 이 도구 위에서 구성된 지식 모듈, 데이터 베이스 및 지식 베이스로 시스템이 구성되었다. 지식 모듈은 주로 교량의 형식 선정과정을 관리하는 설계순서에 관한 지식이고, 지식 베이스 내에 있는 각 부 시스템이 심볼처리에 의해 수행되는 과정에서 데이타 베이스는 이를 지원해 주는 역할을 한다.

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Environmental Monitoring System for Base Station with Sensor Node Networks

  • Hur, Chung-Inn;Kim, Hwan-Yong
    • Journal of information and communication convergence engineering
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    • 제7권3호
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    • pp.258-262
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    • 2009
  • A Practical application of environmental monitoring system based on wireless sensor node network with the core of embedded system STR711FR2 microprocessor is presented in the paper. The adaptable and classifiable wireless sensor node network is used to achieve the data acquisition and multi-hop wireless communication of parameters of the monitoring base station environment including repeaters. The structure of the system is proposed and the hardware architecture of the system is designed, and the system operating procedures is proposed. As a result of field test, designed hardware platform operated with 50kbps bit rate and 5MHz channel spacing at 2040Hz. The wireless monitoring system can be managed and swiftly retreated without support of base station environmental monitoring.

객체지향 데이터베이스를 이용한 지식베이스 모형(OOKS) 개발 (Development of OOKS : a Knowledge Base Model Using an Object-Oriented Database)

  • 허순영;김형민;양근우;최지윤
    • 지능정보연구
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    • 제5권1호
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    • pp.13-34
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    • 1999
  • Building a knowledge base effectively has been an important research area in the expert systems field. A variety of approaches have been studied including rules, semantic networks, and frames to represent the knowledge base for expert systems. As the size and complexity of the knowledge base get larger and more complicated, the integration of knowledge based with database technology cecomes more important to process the large amount of data. However, relational database management systems show many limitations in handing the complicated human knowledge due to its simple two dimensional table structure. In this paper, we propose Object-Oriented Knowledge Store (OOKS), a knowledge base model on the basis of a frame sturcture using an object-oriented database. In the proposed model, managing rules for inferencing and facts about objects in one uniform structure, knowledge and data can be tightly coupled and the performance of reasoning can be improved. For building a knowledge base, a knowledge script file representing rules and facts is used and the script file is transferred into a frame structure in database systems. Specifically, designing a frame structure in the database model as it is, it can facilitate management and utilization of knowledge in expert systems. To test the appropriateness of the proposed knowledge base model, a prototype system has been developed using a commercial ODBMS called ObjectStore and C++ programming language.

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미술 치료를 위한 LMT 그림 진단 지원 시스템 (LMT Diagnosis Assistance System for Art Therapy)

  • 소현경;서영훈
    • Journal of Platform Technology
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    • 제6권1호
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    • pp.24-30
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    • 2018
  • LMT 는 10 가지 풍경요소 그림을 이용하여 내담자의 심리 상태를 분석하는 그림 검사기법이다. 본 논문에서는 LMT 그림 분석에 필요한 지식 베이스를 구축한다. 이를 기반으로 그림 검사 후 내담자에게 제공되는 평가 보고서를 생성하는 LMT 그림 진단지원 시스템을 제안하고, 구현한다. 이 시스템은 각종 문헌 및 연구 결과를 기반으로 진단 결과를 생성하기 때문에 진단 결과의 객관성을 제고한다. 또한, 향후 LMT 그림분석에 대한 지식을 지식 베이스에 축적할 수 있어 지속적으로 확장이 가능하다. 본 시스템은 웹 기반으로 서비스할 수 있도록 구현되었으며, 실제 사례를 이용하여 지원 시스템의 효과성을 보였다.