• 제목/요약/키워드: Gage

검색결과 563건 처리시간 0.027초

정밀발파의 표준화 (Standardization of Cautious blasting)

  • 허진
    • 화약ㆍ발파
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    • 제8권3호
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    • pp.3-13
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    • 1990
  • First ot of all, under given condition such as bit gage of 36mm Drill bit with right class of jack-leg-experimental test carried out from two face of Bench, firing of each hole brought 90 degree Angle face and them measured length of Burden and charged ammount of powder as following. $ca=\frac{A}{SW}$ A=Activated Area A=nd i=m S=Peripheral length of charged, room Ca=Rock Coeffiecency d: di=Hole diameter When constructed subway of Seoul in 1980 the blasting works increased complaint of ground vibration, in order to prevent the damage to structures. Some empirical equations were made as follows on condition with Jackleg Drill (Bit Gage 36mm) and within 30 meter distance between blasting site and structures. $V=K(D/W)^{-n}$ N=1.60 - 1.78 K= 48 - 138 Project is one of contineous works to above a determination of empirical equation on the cautious blasting vibration with Crawler Drill (70-75mm) in long distance. $V=41(D/\sqrt[3]{W})^{-1.41}$ $30m\le{D}\le{100m}$ $V=124(D/\sqrt[3]{W})^{-1.66}$ $100m\le{D}\le{285m}$.

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보 구조물의 응력 변화에 따른 구조역학적 임피던스의 특성 분석 (Analysis of Electro-Mechanical Impedance Characteristics according to the change in stress of beam-type structures)

  • 이포영;박재형;윙 칵 유이;김정태
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2011년도 정기 학술대회
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    • pp.299-302
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    • 2011
  • 본 논문에서는 보 구조물의 응력 변화에 따른 구조역학적 임피던스의 특성을 분석하였다. 이를 위해 다음과 같은 연구가 수행되었다. 먼저 외팔보 형식의 알루미늄 보에 PZT센서와 strain gage를 부착하고, 하중을 단계적으로 증가시키면서 임피던스를 계측하였다. 다음으로 strain gage에서 계측된 변형률과 PZT로 부터 계측된 임피던스 사이의 관계를 분석하였다. 마지막으로 수치해석을 통해 변형률과 임피던스의 관계를 분석하여, 실험결과와 비교하였다.

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보구조물의 모드변형에너지기반 손상 검색: 3가지 타입 센서의 비교 (Modal Strain Energy-based Damage Detection in Beam Structures using Three Different Sensor Types)

  • ;홍동수;김정태
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2011년도 정기 학술대회
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    • pp.680-683
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    • 2011
  • This study deals with damage detection in beam structure by using modal strain energy-based technique with three different sensor types: accelerometer, lead zirconate titanate (PZT) piezoelectric sensor and electrical strain gage. First, the use of direct piezoelectric effect of PZT sensor for dynamic strain response are presented. Next, a modal strain energy-based damage detection method is outlined. For validation, forced vibration tests are carried out on lab-scale aluminum cantilever beam. The dynamic responses are measured for several damage scenarios. Based on damage localization results, the performance of three different sensor types is evaluated.

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플라스틱 손목보조기의 응력 해석 연구 (Stress analysis of plastic hand sprint)

  • 장대진;이한림;김명회;양현석
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2003년도 춘계학술대회논문집
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    • pp.899-902
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    • 2003
  • This study was tested for the bending stress analysis of hand spl int for Hemiplegic Patients. Hemiplegia was represented the stroke and the cerebral palsy. Hand splints of four materials was an Orthoplast hand splint, a Polypropylene hand splint, a Yogips hand splint and an Aluminum hand splint. The Stress Analysis system was made by the electronic oscilloscope, strain gage sensors, amplifier, A/D converter, PC with C program. It will be able to using the important data in spl int design. The results of analysis were obtained various different graphes and maximum data in an Orthoplast hand splint, a Polypropylene hand splint, a Yogips hand splint and an Aluminum hand spl int.

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플라스틱 발목보조기의 응력해석 연구 (Stress Analysis of Plastic Sprint)

  • 김명회;이창로;장대진;고흥
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2003년도 춘계학술대회논문집
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    • pp.888-892
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    • 2003
  • This study was tested for the bending stress analysis of Experimental stress analysis on various ankle foot orthoses(AFOs) was fulfilled. Stress was measured by Strain gages which were attached on 8 region in AFOs Results revealed that the peak compressive/tensile stress in the orthoses occured in the lateral region of neck. The Stress Analysis system was made by the electronic oscilloscope, strain gage sensors, amplifier, A/D converter, PC with C program It will be able to using the important data in splint design. Selected AFOs were some different materials but all have same shape except one type(orthosis with joint). C program Is used for managing data. Thus lateral side of the neck region is failed easily.

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차륜/레일 기하학적 인자의 등가답면구배에 미치는 영향 (A study on the influence of wheel/rail geometric parameters to equivalent conicity)

  • 허현무;권성태;김형진
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 추계학술대회 논문집
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    • pp.430-434
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    • 2004
  • The geometric parameters between wheel and rail change wheel/rail contact geometry characteristics, and this influence dynamic behavior of rolling stock. So, the selections of optimum geometric parameters between wheel and rail is important for planning of railway system. In this study, we have analyzed the influence of geometric parameters like wheel flange-back distance, gage, and rail inclination to the equivalent conicity relating dynamic behavior. The analyses show the following results. The widening of wheel flange-back distance increase the equivalent conicity, the widening of gage, rail inclination 1/20 compared with rail inclination 1/40 decrease the equivalent conicity.

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스트레인게이지 응용 6축 힘-토크 센서의 신호처리와 성능 (Signal Processing and Performance of a Six-Axis Force-Torque Sensor Using Strain Gauges)

  • 이재호;강철구
    • 제어로봇시스템학회논문지
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    • 제7권2호
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    • pp.146-151
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    • 2001
  • The importance of sensing the force and torque with arbitrary direction and magnitude is becoming more crucial for robotic applications and manufacturing automations. Recently, several designs of a multi-axis force-torque sensor have been tried to sense this force and torque. This paper deals mainly with the signal processing of a six-axis force-torque sensor using cross-shaped elastic structures with circular holes. In this paper, we show principle of sensing force and torque, the signal processing methodology, and efficient methods of seeking strain gage positions in the sensor structure. The validity of the proposed method is shown via experiments.

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표면온도 차이에 의한 표면마찰력 측정 오차에 대한 연구 (A Study on the Errors in Skin Friction Measurements due to Surface Temperature Mismatch)

  • 백승욱
    • 한국군사과학기술학회지
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    • 제3권2호
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    • pp.213-218
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    • 2000
  • An experimental study was performed to investigate the effect of surface temperature mismatch on measurements of skin friction using a plug-type skin friction gage mounted on the side wall of a supersonic wind tunnel. The freestream Mach number was 2.4 and Reynolds number per meter was $5.25 {\times}10^7$ with total pressure of 50 psi and total temperature of 275K. Temperature mismatch between the gage surface and surrounding wall surface was generated by hot water injection using the active temperature control system. Results of the tests showed that the temperature mismatch made sizable effects on the measurements of skin friction.

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밀폐형 왕복동압축기의 리드밸브 동특성에 관한 연구 (A Study on the Dynamic Characteristics of Reed Valves in Hermetic Reciprocating Compressors)

  • 김정우;김현진;박희용
    • 설비공학논문집
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    • 제4권3호
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    • pp.163-174
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    • 1992
  • This paper presents numerical and experimental methods of investigating dynamic characterisics of reed valves of hermetic reciprocating compressors. For the natural frequency, two different techniques have been tried : microphone method and strain gage method. In the microphone method, acoustic pressure signals from excited valves have been analyzed, while signals of tiny strain gauge attached on the reed valves have been utilized in the strain gage method. The empirically determined natural frequencies have been compared to the ones calculated by finite element method. Reasonably good agreements between the experimental and numerical results have been found, implying that the natural frequencies of reed valves could be obtained by FFM alone with enough accuracy.

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An Ideal strain gage placement plan for structural health monitoring under seismic loadings

  • Vafaei, Mohammadreza;Alih, Sophia C.
    • Earthquakes and Structures
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    • 제8권3호
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    • pp.541-553
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    • 2015
  • Structural Health Monitoring (SHM) systems can provide valuable information regarding the safety of structures during and after ground motions which can be used by authorities to reduce post-earthquake hazards. Strain gages as a key element play an important role in the success of SHM systems. Reducing the number of required strain gages while keeping the efficiency of SHM system not only can reduce the cost of structural health monitoring but also avoids storage and process of uninformative data. In this study, a method based on performance based seismic design of structures is proposed for ideal placement of stain gages in structures. The robustness and efficiency of the proposed method is demonstrated through installation of strain gages on an Airport Traffic Control (ATC) Tower. The obtained results show that the number of required strain gages decrease significantly.