• 약학회지
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• 제51권6호
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• pp.435-439
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• 2007

Novel asiaticoside mimetics simplified the sugar moiety by tetrahydropyrans (THP) were designed, synthesized and tested their wound healing effects by tensile strength measurement. From this study, it is speculated that the sugar moiety of asiaticoside could be simplified to tetrahydropyrans without a significant loss of wound healing effect.

• Journal of the Korean Wood Science and Technology
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• 제31권3호
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• pp.35-41
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• 2003

The mechanical and physical properties of wood are strongly dependent upon the slope of grain. Specially, tensile strength is more severely affected by the slope of grain. Therefore, tension tests were performed on small thin wood samples made from Pinus radiata with varying the slope of grain. Determining the tensile strength for clear thin wood samples the other variabilities associated with material, size, drying, defects, etc were discarded. Slope of grain was measured by the slope of grain indicator and actual slope of grain was also determined by a protractor. Correlation coefficients between machine measured and actual slope of grain for 40 pieces of 2×20 mm, 300 mm long Pinus radiata were 0.84 for wide face measurement. Results also showed that tensile strength and MOE from stress wave tests decreased with increasing the slope of grain. This study did not establish a relationships for tensile strength and MOE from stress wave with slope of grain. However, the trends of MOEs from stress wave test with both slope of grain are agreed well with Hankinson's equation. Predicted tension strength curve by Hankinson's equation was also agreed well with the experimental data over the range from 0 to 13 degrees for slope of grain.

• 소성∙가공
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• 제12권5호
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• pp.504-512
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• 2003

The plastic strain ratios(R-values) of low carbon steel sheets were determined by the automatic strain measurement method using two extensometers, the indirect photo method for the same tensile specimen during tensile test and the indirect method for the specimen after tensile test. The experimental results showed that the measured plastic strain ratios from the automatic strain measurement method using two extensometers coincided with those from the indirect photo method and the indirect method for all tensile specimens. In addition, the strain dependence of plastic strain ratios could be continuously recorded and the anisotropy of the strength coefficient, K, and strain hardening exponent, n, could be automatically calculated in three directions by computer through the use of two extensometers. The experimental results showed that the strain dependence of R-value was related to the anisotropy of strain hardening exponent in low carbon steel sheets.

• 대한토목학회논문집
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• 제26권6C호
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• pp.377-384
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• 2006

다짐된 모래-벤토나이트 혼합토의 인장강도 측정을 위한 새로운 시험방법을 개발하기 위하여 일축관입(UP)시험에 대한 이론적 실험적 측면에서의 연구를 실시하였다. 다짐된 혼합토의 인장강도는 완전소성이론을 이용한 한계해석으로부터 계산될 수 있으며 개량일축관입시험기(Improved Unconfined Penetration, IUP)는 기존의 일축관입시험기와 비교하여 시험기기의 개선을 통해 측정 오류를 감소시켰다. 선행 시험 결과 원반의 크기와 재하속도의 증가와 pH가 높아(산성)짐에 따라 인장강도가 증가함을 알 수 있었다. 또한 원반 직경이 25.4mm이며 재하속도가 0.5%/min~1%/min일 경우가 개량일축관입시험에 가장 적합하다는 것을 알 수 있었다. 할렬인장시험 결과와의 비교를 통해 개량일축관입시험법의 신뢰성도 확인하였다.

• 한국응용과학기술학회지
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• 제37권5호
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• pp.1248-1256
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• 2020

In this study, the polyurethane resin was synthesized by applying PTMG and DMBA of different composition ratios for the synthesis of water-dispersible polyurethane used in wound coating resin. The varying properties of the synthesized water-dispersible polyurethane were measured through tensile strength, elongation, and abrasion resistance analysis. As for the tensile strength measurement result according to the PTMG content, the sample with the highest reaction molar ratio was measured as 1.08 kgf/mm2 and the elongation was measured as 520%. As for the tensile strength result according to the DMBA content, the sample with the highest reaction molar ratio was measured as 0.51 kgf/mm2, and the elongation was measured as 435%. The degree of surface destruction by the abrasion resistance measurement was visually confirmed through SEM.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1321-1325
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• 2003

Nickel thin film is one of the most important materials used in micromachined structure. To measure the mechanical properties of electroplated nickel thin film, two techniques are adopted and compared quantitatively with. One is nano-indentation test to measure the elastic modulus. The other is tensile test to measure not only elastic modulus but also yield strength and plastic deformation, ultimate strength. To perform the tensile test, the test apparatus was constructed with linear guided servo motor for actuation, load cell for force measurement and dual microscope for strain measurement.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1996년도 추계학술대회논문집
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• pp.85-92
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• 1996

The Measurement method of the plastic strain ratio is various in Automotive sheet steel. In this paper, the measurement of the plastic strain are used two different methods, ASTM E 517 method and the automatic strain measurement tensile specimen during the tensile test, and compared the plastic strain ratios from the two methods. The experimental results showed that the measured plastic strain ratios from the automatic strain measurement method are coincide with that from the ASTM E 517 standard measurement in various specimens. Therefore, automatic strain measurement method by two extensometers shows good accuracy. Also, the strain dependance of plastic strain ratios could be recorded by the computer continuously and anisotropy of the strength coefficient, K, and strain hardening exponent, n ,could be compared with each direction automatically through the use of automatic strain measurement system.

• Advances in concrete construction
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• 제3권4호
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• pp.269-282
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• 2015

In this paper, a compression to tensile load converter device was developed to determine the anisotropic tensile strength of concrete. The samples were made from a mixture of water, fine sand and cement, respectively. Concrete samples with a hole at its center was prepared and subjected to tensile loading using the compression to tensile load converter device. A hydraulic load cell applied compressive loading to converter device with a constant pressure of 0.02 MPa per second. Compressive loading was converted to tensile stress on the sample because of the overall test design. The samples have three different configurations related to loading axis; 0, $45^{\circ}$, $-45^{\circ}$. A series of finite element analysis were done to analyze the effect of hole diameter on stress concentration of the hole side along its horizontal axis to provide a suitable criterion for determining the real tensile strength of concrete. Concurrent with indirect tensile test, Brazilian test and three point loading test were also performed to compare the results from the three methods. Results obtained by this device were quite encouraging and show that the tensile strengths of concrete were similar in different directions because of the homogeneity of bonding between the concrete materials. Also, the indirect tensile strength was clearly lower than the Brazilian test strength and three point loading test.

• 한국전기전자재료학회논문지
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• 제28권2호
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• pp.126-130
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• 2015

In this study, some materials are organized and experimented with variables to obtain the optimum mix proportion for the mechanical property of halogen free flame resistance compound with varying addition of nano clay. Tensile strength, density and stiffness are tested in the room temperature. In this study, unlike existing layered structure, nano clay with tabular structure is used and sufficient stiffness, strength, thermal stability and gas block capability can be achieved with small amount of addition. Tensile strength and elongation test show high rupture strength only in specimens with compatibilizing agents while density test shows average measurement in all the specimens except T-9. It was confirmed that the measurement value according to the additives in compatibilizing agent or in nano clay of hardness test represents similarly.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1059-1062
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• 2003

Micro-tensile testing system has been developed and micro-tensile tests for copper foil have been carried out. The system consisted of a micro tensile loading system and a micro-ESPI system for measuring strain. The loading system has a maximum loading capacity of 50N and a stroke resolution of 4.5nm. Stress-strain curves for the electro-deposited copper foil with the thickness of 18$\mu\textrm{m}$ were obtained, and tensile properties, including elastic modulus, yielding strength and tensile strength, were determined. The tensile properties obtained under three different conditions of testing speed showed a dependency on the speed.