• 제목/요약/키워드: speed restriction

검색결과 108건 처리시간 0.027초

DCM(심층혼합처리공법)에 의한 자립식 흙막이 적용사례 (Application for Self-Supported Retaining Wall Using Deep Cement Mixing)

  • 정경환;김용완;신민식;한경태;김태효
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 2006년도 춘계 학술발표회 논문집
    • /
    • pp.257-267
    • /
    • 2006
  • The earth retaining wall systems for excavation works in a populated urban area or a poor soil deposit can be limited due to various restriction. Thus there are various methods to be applied for them such as the soldier pile method, the diaphragm wall with counterfort and so on. In this study, the self-supported earth retaining wall using the DCM(Deep Cement Mixing) method, including its merits, demerits and some important characteristics occured in the design and the construction stage, was introduced. It might be reference for the other design and construction procedures using the DCM method.

  • PDF

A Practical Method of Prediction of Resistance for Displacement Vessels

  • Doctors, Lawrence J.
    • Journal of Ship and Ocean Technology
    • /
    • 제1권2호
    • /
    • pp.1-10
    • /
    • 1997
  • The prediction of the total resistance of a ship is generally based on considering it to be a simple sum of the viscous resistance and the wave resistance. An experimental approach for predicting full-size ship resistance on this basis is practical but obviously has the deficiency that a model has to be built for each prototype of interest and the resulting tank tests are time consuming. On the other hand, purely theoretical calculations of the wave resistance, using, for example, the Michell theory, require relatively little computer time and give an excellent portrayal of the overall variation of the vessel resistance as a function of forward speed. Unfortunately, there are sufficient differences between this theory and the measured results to make this method impractical for design purposes. The proposal examined here is to use a data bank of experimental resistance results to modify the theoretical predictions. It is demonstrated that the technique will produce remarkably accurate resistance predictions and can take into account the effects of the water depth, any restriction of canal or river width, as well as the prismatic coefficient, and other geometric parameters.

  • PDF

모바일 디지털카메라 모듈에 대한 개선된 AE 알고리즘 구현 (An Improved AE System for Mobile Digital Still Camera)

  • 조선호;김동한;박종국
    • 제어로봇시스템학회논문지
    • /
    • 제14권5호
    • /
    • pp.426-431
    • /
    • 2008
  • In this paper, an improved AE system for digital still camera is proposed. AE system is auto exposure system to maintain optimized brightness of output image. But there is limitation for mobile devices to get high quality image with the conventional AE algorithm, because of organizational restriction of system. The conventional research has been studied only electronic shutter and AGC on the AE algorithm. In this paper, we suggest new AE algorithm included target setting, frame delay, Gamma Correction as well as electronic shutter and AGC to get high quality image. The proposed algorithm show improved result at control speed and ability of luminance expression.

5축 가공을 이용한 쾌속조형 시스템의 개발 (A study on the development of rapid prototyping system using 5 axis machining)

  • 정태성;양민양
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2002년도 추계학술대회 논문집
    • /
    • pp.1011-1014
    • /
    • 2002
  • In order to reduce the lead-time and cost, many useful methods have been applied to Rapid Prototyping (RP) in recent years. But cutting process is still considered as one of the effective RP methods that have been developed and currently available in the industry. It also owen practical advantages such as precision and versatility. However, traditional 3 axis NC machining has some inherent limitations such as the restriction of tool accessibility and the complex setup. In this work, a new rapid prototyping system with high speed 5 axis machining has been developed to overcome those limitations. The architecture of developed system is described in detail and the successful application examples are presented.

  • PDF

이방성 Plasma 내에서 운동중인 Source에 의한 전자계 (Electromagnetic Fields Due to Moving Sources in Anisotripic Plasma)

  • Kim, Young-Cho
    • 대한전자공학회논문지
    • /
    • 제23권2호
    • /
    • pp.149-169
    • /
    • 1986
  • Fundamentals of electrodynamics of moving sources with constant velocity in an anisotripic plasma when the do magnetic field and the relative motion are oriented in arbitrary directions are presented. The well-known Minkowski's relations are generalized to accomodate anisotropic and dispersive media, and relativistic transformation formulae of constitutive parameters are derived and expanded into polynomials of the speed ratio \ulcornerto increase the utility of the formulae. The helmholtz wave equation of electromagnetic fields is generalized to the media charactrized by tensor parameters, and is solved in operator form. Also the solution of wave equation is expressed as a porcuct of the inverse of the wave operator matrix and the source function vector, and the inverse of the wave operator matrix is presented in an explicit form. The equations and formulae derived in this paper are all general, and can be reduced to known and proven results upon imposing the restriction called for by specific situations.

  • PDF

가시화 엔진을 이용한 직분식 디젤 엔진의 분무 연소 특성에 관한 연구 (A study on the spray combustion characteristics of D.I. diesel engine using visualization engine system)

  • 정재우;이기형;최석우;김병수
    • 한국분무공학회지
    • /
    • 제4권4호
    • /
    • pp.17-23
    • /
    • 1999
  • Recently, many researchers have been studied a D.I. diesel engine because of the exhaust gas restriction and fuel consumption performance. It is well known that the fuel injection characteristics are the key factors on the diesel combustion and exhaust emission. In this study, the fuel injection characteristics of 5-hole injector and the combustion characteristics are investigated with the amount of fuel by means of the visualization method and visualization D.I. diesel engine system. As the results of the experiments, the spray pattern of the fuel injection and the diffusion flame of a D.I. diesel engine are clarified. In addition, combustion phenomena with operation conditions such as engine speed and engine load are made clear.

  • PDF

Binary CDMA 기반 차량용 카메라 시스템의 무선 영상전송기 개발 (Development of a Wireless Video Transmitter for Automobile Camera System based on the Binary-CDMA Technology)

  • 최재원
    • 한국정보통신학회논문지
    • /
    • 제18권7호
    • /
    • pp.1571-1578
    • /
    • 2014
  • Binary CDMA는 음성 영상 등의 멀티미디어 데이터를 초고속으로 우수한 전송품질로 통신할 수 있는 우리나라가 개발한 새로운 표준 무선통신 기술이다. 본 논문에서는 유선의 제약 없이 자유롭게 설치 가능한 차량용 무선 카메라 시스템의 개발을 위해 이의 핵심 장치인 Binary CDMA 무선 영상전송기와 중계기의 설계와 구현에 관해 연구하였다.

Linux에서 SQLite 데이터베이스의 검색 성능 분석 (Search Performance Analysis of SQLite Database on Linux)

  • 최진오
    • 한국정보통신학회:학술대회논문집
    • /
    • 한국정보통신학회 2016년도 춘계학술대회
    • /
    • pp.390-391
    • /
    • 2016
  • SQLite는 리소스 제약이 큰 소형 기기에 적합한 데이터베이스 엔진이며 리눅스 기반 모바일 기기에 많이 사용되고 있다. SQLite는 오픈소스 프로그램이며 가볍고 속도가 빠른 장점을 지닌다. 이 논문에서는 리눅스 기반 환경에서 SQLite 데이터베이스의 검색 성능을 테스트하여 장단점을 분석하고자 한다. 분석은 같은 환경에서 실행되는 다른 데이터베이스와 비교하여 진행한다.

  • PDF

철도신호장치를 위한 지상신호 Emulator의 개발 (Development of a Wayside Signaling Emulator in Railway Signaling Systems)

  • 이을재;양이우;김영석;변종영
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1998년도 추계학술대회 논문집 학회본부A
    • /
    • pp.350-353
    • /
    • 1998
  • In this paper, a wayside signaling emulator systems developed for testing to carbone ATC/ATO/TWC systems adopted in SMRT(Seoul Metropolitan Rapid Transit Coperation) line 7, 8 is presented. Informations that are required to train movement with driverless, such as stations status, destination station, restriction speed and train modes are provided through the wayside signaling emulator. The developed emulator systems can be constructed to 1.5km testing tracks and the end points of track, are emulated to the arbitrary stations in SMRT line 7, 8.

  • PDF

Linux환경에서 SQLite 데이터베이스의 검색 성능 실험 (Search Performance Experiments of SQLite Database on Linux Environments)

  • 김수환;최진오
    • 한국정보통신학회:학술대회논문집
    • /
    • 한국정보통신학회 2016년도 추계학술대회
    • /
    • pp.445-447
    • /
    • 2016
  • SQLite, Realm 등은 리소스 제약이 큰 소형 기기에 적합한 데이터베이스 엔진들이며 리눅스 기반 모바일 기기에 많이 사용되고 있다. 이 엔진들은 대부분 오픈소스 프로그램들이며 범용 데이터베이스에 비해 가볍고 속도가 빠른 장점을 지닌다. 이 논문에서는 리눅스 기반 환경에서 SQLite 데이터베이스의 검색 성능을 파악하기 위한 테스트 프로그램을 구현하고 성능 실험을 실시한다. 실험은 같은 환경에서 실행되는 Oracle 데이터베이스와 비교하여 진행한다.

  • PDF