• 제목/요약/키워드: STRAIN

검색결과 22,187건 처리시간 0.038초

수용성 적색 색소를 생산하는 Serratia marcescens US50-3 균주의 분리 및 동정 (Isolation and Identification of Serratia marcescens strain US50-3 Producing Water-Soluble Red Pigment)

  • 양인영;황순욱
    • 한국미생물·생명공학회지
    • /
    • 제23권6호
    • /
    • pp.777-780
    • /
    • 1995
  • A strain US50-3 producing water-soluble red pigment was isolated from the pond separating oil from water near the oil storage tanks. The strain US50-3 was identified as a strain of Serratia marcescens considering its morphological and physiological characteristics, and DNA G+C contents. It showed a little difference comparing to the Type strain and was considered to be another biotype strain.

  • PDF

단일 모-드 광섬유 스트레인 게이지 (Single-mode optical fiber strain gauge)

  • 이기완;김병교
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
    • /
    • pp.1198-1203
    • /
    • 1991
  • A single w& optical fiber strain gauge subjected to the excited PZT-plate is presented which was obtained using a Mach-Zehnder interferometer. This paper has been performed the considerations to the experimental situation In which the dynamical behavior of a optical fiber strain gauge is illustrated. A comparison is reported between the dynamic response of a optical fiber strain gauge and the semiconductor strain gauge in the frequency range 5-50Hz. This result is shown in very good usage as the dynamical measurement of the low strain below l.mu..epsilon. by this system.

  • PDF

화상처리법을 이용한 곡면변형률 측정에 관한 연구 (A Study on the Measurement of Surface Strain Using the Image Processing Technique)

  • 김영수;김형종
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 1997년도 춘계학술대회논문집
    • /
    • pp.213-216
    • /
    • 1997
  • The measurement of 3D surface strain using the image processing method is another approach for strain measurement. The advantage of this method is that strains at several points included in a captured image can be obtained automatically from only one process. In this study, the whole process of automated surface strain measurement is presented. The strain distribution on a LDH specimen is illustrated as a result of the trial to develope an automated strain measurement system.

  • PDF

강구조부재 연결부의 변형특성 및 안전도에 관한 연구 (A study on strain specification and safety degree of connection joints of steel structural member)

  • 김경진;김두환
    • 기술사
    • /
    • 제19권4호
    • /
    • pp.5-10
    • /
    • 1986
  • On SWS 41 Plates jointed by the F11T M 20 high strength bolts the study on stress behavior and safety degree until rupture in static tensile tests were performed. By these results, in case of no clamping force stress concentration was extremed for strain of about 10% higher ratio. Elastic strain occurred to change of test specimens depth by the load and plastic strain occurred to local minute sleep after elastic strain. compared shear stress with tension stress from the fracture load it was showned lower values than the maximum shear stress theory and stress strain energy theory.

  • PDF

변위응답의 측정으로부터 변형률응답의 예측 (Prediction of Strain Responses from Displacement Response Measurements)

  • 이건명;신봉인;이한희
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2001년도 추계학술대회논문집 II
    • /
    • pp.1384-1387
    • /
    • 2001
  • Presented is a method to predict strain responses from displacement measurements on a mechanical structure. The method consists of forming a transformation matrix, which is calculated from displacement and strain modal matrices. The modal matrices can be obtained by either finite element analysis or modal testing. One disadvantage of the method is that it requires displacements on all measuring points be measured simultaneously. The strain prediction method is applied to a simple simulated system.

  • PDF

액압성형공정을 적용한 엔진크레들의 가공 경화 특성 연구 (A Study on the strain hardening behavior of hydroformed Engine Cradle)

  • 박현규;임흥섭;이혜경;김광순;문영훈
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 2008년도 추계학술대회 논문집
    • /
    • pp.154-157
    • /
    • 2008
  • It is important to know the variations of the mechanical properties in the hydroforming process for the safe and durable design purposes. In this study, strain hardening behavior during hydroforming has been investigated by hydroforming of engine cradle as a model process. The variation of mechanical properties such as local hardness and flow stress were used as an index of strain hardening during respective processes. By using the inter-relationships between hardness-flow stress-effective strain at variable pre-strains, the strain hardening behavior during hydroforming has been successfully analyzed. The comparison of predicted hardness with measured hardness confirmed that the methodology used in this study was feasible and the strain hardening behavior can be quantitatively estimated.

  • PDF

Nanoscale Longitudinal Normal Strain Behavior of ${Si_3}{N_4}$-to-ANSI 304L Brazed Joints under Pure Bending Condition

  • Seo, D.W.;Lim, J.K.
    • International Journal of Korean Welding Society
    • /
    • 제4권1호
    • /
    • pp.46-52
    • /
    • 2004
  • To combine the mechanical advantages of ceramics with those of metals, one often uses both materials within one composite component. But, as known, they have different material properties and fracture behaviors. In this study, a four-point bending test is carried out on $Si_3N_4$ joined to ANSI 304L stainless steel with a Ti-Ag-Cu filler and a Cu interlayer at room temperature to evaluate their longitudinal strain behaviors. And, to detect localized strain, a couple of strain gages are pasted near the joint interfaces of the ceramic and metal sides. The normal strain rates are varied from $3.33{\times}10^5$ to $3.33{\times}10^{-1}s^{-1}$ Within this range, the experimental results showed that the four-point bending strength and the deflection of the interlayer increased with increasing the strain rate.

  • PDF

포화점성토의 비배수 CREEP 성질에 의한 공극수압의 거동 (Pore Water Pressure Behavior due to Undrained Creep of Saturated Clay)

  • 강우묵;조성섭;지인택
    • 한국농공학회지
    • /
    • 제30권3호
    • /
    • pp.38-50
    • /
    • 1988
  • carried out to present a rheology model which is able to treat time-dependent properties of clay. The results were summarized as follow ; 1. The slope (a(e1)) of deviator stress in strain rate test was independent on axial strain, and pore water pressure was decreased with increment of strain rate. 2. The pore water pressure in a stress relaxation condition was not changed when the strain rate before stress relaxation was 0.05%/min., but it was increased with increment of time when the strain rate before stress relaxation was 0.2%/min 3. The greater the stress condition (q/qmax) and the strain rate before creep test became, the greater the increment rate of axial strain in creep test became. 4. SEKIGUCHI's constitutive equation was slightly overpredicted while empirical equation proposed in the study was well coincided with measured values. 5. The constitutive equation induced by a strain function could be dealed with a behavior of the pore water pressure increased with increment of elapsed time after primary consolidation.

  • PDF

FBG 센서를 삽입한 3차원 브레이드 하이브리드 복합재료의 잔류변형률 및 내부변형률 측정 (Measurement of Residual and Internal Strain of 3-D Braided Hybrid Composite using Embedded FBG Sensor)

  • 정경호;김돈건;강태진
    • 한국복합재료학회:학술대회논문집
    • /
    • 한국복합재료학회 2005년도 춘계학술발표대회 논문집
    • /
    • pp.21-24
    • /
    • 2005
  • Three dimensional circular braided Glass/Aramid hybrid fabric/epoxy resin composite was fabricated. FBG sensor was embedded along the braid yam in order to monitor the internal dimensional changes of the 3-D braid composite. The amount of cure and thermal shrinkage of epoxy resin was also determined using FBG sensor system. FBG sensors with different grating length were embedded and their response were compared. The thermo-optic coefficient of FBG sensor was measured by several preliminary experiments. The internal strain that measured by FBG sensor and electric strain gauge was compared during compressive test. The released residual strain of the fabricated tubular composite was estimated using cutting method. The internal strain of the composite was estimated using FBG sensor system, and the result was compared with the value from electric strain gauge. It was found that FBG sensor system is a very useful technique to investigate inside region of complicated structure.

  • PDF

A Study on Dynamic Crack-Tip Fields in a Strain Softening Material

  • Jang, Seok-Ki;Xiankui Zhu
    • Journal of Advanced Marine Engineering and Technology
    • /
    • 제27권4호
    • /
    • pp.494-502
    • /
    • 2003
  • The near-tip field of mode-I dynamic cracks steadily propagating in a strain softening material is investigated under plane strain conditions. The material is assumed to be incompressible and its deformation obeys the $J_2$ flow theory of plasticity. A power-law stress-strain relation with strain softening is adopted to account for the damage behavior of materials near the dynamic crack tip. By assuming that the stresses and strain have the same singularity at the crack tip. this paper obtains a fully continuous dynamic crack-tip field in the damage region. Results show that the stress and strain components the same logarithmic singularity of (In(R/r))$\delta$, and the angular variations of filed quantities are identical to those corresponding to the dynamic cracks in the elastic-perfectly plastic material.