• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2002년도 ICCAS
• /
• pp.79.2-79
• /
• 2002

1. the principal of a PSD(Position Sensitive Detector) 2. the optical system of the proposed method 3. signal processing 4. experimental result A mechanical engineer experiment on the tension test. In this experiment, they use the extensometer which can measure the extended distance of material. A normal extensometer is the contact type which means that the extensometer should attached to the specimen. It is not convenient to the user. The contacting type can also effect the characteristic of the specimen. So a extensometer is changed from contacting type to non-contacting type. Non-contacting type is not necessary to attach the extensometer to the specimen...

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2008년도 추계학술대회A
• /
• pp.368-371
• /
• 2008

An extensometer system to measure strain and displacement of cylindrical fatigue specimen in a autoclave of high temperature and high pressure environment has been developed by KEPRI. The extensometer reads the displacement caused by fatigue loads at the target length of the specimen installed inside the autoclave. The performance of the extensometer were tested at 15MPa, $315^{\circ}C$ of a operating pressurized water reactor. Two LVDT's of magnet type were connected to the extensometer and used for converting the fatigue displacement to electronic signal. The device is being used for developing environmental fatigue curve of CF8M cast austenitic stainless steel (CASS) in the test condition of low cycle and low strain. This paper introduces the background and results of the development.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2002년도 추계학술대회 논문집
• /
• pp.1085-1087
• /
• 2002

Deformation of soft tissue is known inhomogeneous and non-linear in general. In this study, we propose a measurement methodology of local/global strain during soft tissue elongation precisely using laser extensometer which has high accuracy, resolution and is possible to measure global/local strain. The mechanical tensile test are performed on tibialis cranialis, flexor hallucis longus, extensor digitorum longus of swine hindlimb. In order to measure target displacement, reflective marker is attached to detect elongation on specimen using surgical adhesive. The result of this study is to show that laser extensometer is valid to measure longitudinal elongation which is inhomogeneous and non-linear fur soft tissue.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2000년도 가을 학술발표회 논문집
• /
• pp.607-614
• /
• 2000

A cost-effective automated slope monitoring system is developed to monitor hazardous cut slopes along highways. This automated slope monitoring system consists of data-collection and visual monitoring, data-transmitting, database and internet service, and alarm system. Wire-line extensometer, automatic raingauge, and CCD camera are selected as monitoring instruments in this system, after consideration of failure characteristics of roadside cut slopes in the country. This paper describes the important features of this newly developed automated slope monitoring system.

• 터널과지하공간
• /
• 제4권3호
• /
• pp.297-304
• /
• 1994

This study aimed at analysis of induced stress and deformation behavior in rock mass around coal seams of Sam Chuck coal mine. For this study Vibrating Wire Stressmeters and Multi-point Borehole Extensometers were installed in the area of coal shale near coal seams. Induced stress and displacement in this area were coutinuously increased for 6 days from the begining of measurement, and then converged. But induced stress and displacement occurred when there were another openings by tunnelling and mining. The value of final induced stress was 21.8kgf/$\textrm{cm}^2$, displacement of rod extensometer was 1.3 mm at arch. Especially, over 1 mm of displacement between E2 and E3 in rod extensometer was measured.

• 한국초전도ㆍ저온공학회논문지
• /
• 제13권4호
• /
• pp.14-17
• /
• 2011

The evaluation of the electromechanical properties of HTS CC tapes is one of the foremost procedures to be done to ensure the applicability of superconducting wires to electric devices. A precise measurement of the stress and strain is important in deriving the mechanical properties under operating environment. Up to now, there is no standard test method yet for the electromechanical property evaluation of HTS tapes under self field and external magnetic field although there are already reports on the different devices used to evaluate these properties. Strain can be measured by adopting a strain gauge or a high resolution double extensometer. In this study, strain effect on $I_c$ in HTS CC tapes under magnetic fields was evaluated. Comparison of advantages and setback of strain measuring devices were discussed. In addition, a dual strain measurement system using both the SG and extensometer may be practical to lessen the burden in case one of the measuring devices does not work well.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 1996년도 가을 학술발표회 논문집
• /
• pp.61-70
• /
• 1996

• 화약ㆍ발파
• /
• 제10권4호
• /
• pp.19-50
• /
• 1992

This Study is Concerned about the Gage Controled analysis in Tunneling. Gage Control was to analysis made by recording paper such as Convergence meter, Inclinometer and extensometer etc.

• 지질공학
• /
• 제33권1호
• /
• pp.27-37
• /
• 2023

땅밀림은 균열 및 단차가 오랜시간에 걸쳐 발생하기 때문에 장기적인 모니터링이 반드시 필요하다. 그러나 사면변위계, 경사계 등을 이용한 장기모니터링은 비용 및 관리 차원에서 비효율적이다. 따라서 본 연구에서는 땅밀림이 진행 중인 지역을 테스트베드로 선정하고 영상을 이용한 모니터링 가능성을 평가하였다. 이를 위해 지상라이다와 드론을 이용하여 땅밀림 모니터링을 실시하고 계측자료와 비교하였다. 현장 계측은 사면변위계를 설치하여 분단위 측정을 실시하였다. 분석값의 비교결과 정확도에 따라 미세한 차이는 있지만 지상라이다와 드론을 이용한 모니터링에서도 사면변위계와 유사한 값을 얻을 수 있었다. 이는 땅밀림의 정밀분석 및 예측을 위해서는 분단위의 현장계측이 필요하지만 지상라이다 및 드론을 활용한 기초 모니터링의 가능성을 보여준다. 향후 다양한 차원에서 영상분석에 대한 검증이 이루어지고 기후, 정확도 등을 고려한 데이터가 누적되면 영상을 이용한 정밀 모니터링도 가능할 것으로 판단된다.

• 산업기술연구
• /
• 제20권A호
• /
• pp.257-267
• /
• 2000

It was difficult to apply conventional excavation methods in some sections from Seoul to Pusan high speed rail road construction of 1 lot 2, due to highway concrete road, gas pipe, water pipe and nearby factories with automatic control system machine. To excavate safely and efficiently in these sections new blast patterns were employed within allowable blast vibration level, by test blast and controlled vibration by sequential blast. Behaviors of the rock mass including convergence and displacement around tunnel were measured with construction works and the crack width in concrete wall was also monitored for controlling allowable limits. The results can be summarized as follow : 1. The allowable blast vibration level in structure site is less 1.0cm/sec for highway concrete, 0.5 cm/sec for gas pipe, water pipe and building housing and 0.3 cm/sec for automatic control system machine. 2. The convergence displacement, single rod extensometer and multi rod extensometer around tunnel and cracks in concrete wall were measured, it was confirmed that the measured values were converged within allowable level. 3. The empirical formular of ground vibrations with 90% confidence lines for PD-3 was given as follow. $$V_{90%}=45.549({\frac{D}{\sqrt{W}}})^{-1.353}$$