• Title/Summary/Keyword: I-T curve

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I-t Curve Simulation of the Low Voltage Distriubtion Line Fuse (저압배선용 전선퓨즈의 I-t곡선 시뮬레이션)

  • 박두기;이세현;박영범;구경완;김종식;한상옥
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1996.11a
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    • pp.214-217
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    • 1996
  • In this paper. we deal wish the I-t characteristic of law voltage distribution fuse. It is used to be thermal characteristic in being produced at fuse element part. The elements are divided low temperature melting element(LTME) by high temperature melting element(HTME). Those parts make of coordination. The characteristic of fuse is decided by material and design etc. used at element. We analysis I-t characteristic curve by using the numerical method. And we compared the curve of simulation with that of experiment

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T-curve, wear and Erosion of Silicon Carbide (탄화규소의 T-curve, 마모 및 침식)

  • 채준혁;조성재;윤경진;김석삼
    • Tribology and Lubricants
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    • v.14 no.4
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    • pp.114-120
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    • 1998
  • The T-curve, wear and erosion behaviors of two different silicon carbides, i.e., the fine grained SiC and the in situ-toughened SiC(IST-SiC). Both materials exhibited an increasing T-curve behavior, although the T-curve of IST-SiC was steeper than that of fine grained SiC. The fracture toughness of IST-SiC was larger than that of fine grained SiC at long crack regime, whereas an opposite tendency occurred at short crack regime. The rate of material removal during wear and erosion tests was higher in IST-SiC compared to fine grained SiC. The difference between the material removal rates of two materials was discussed in the light of their R-curve behaviors.

The comparison of the fatigue crack initiation life in a notch (노치부의 피로균열발생 수명 비교)

  • Kim, S.H.;Bae, S.I.;Ham, K.C.;Song, J.I.
    • Proceedings of the KSME Conference
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    • 2001.06a
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    • pp.217-222
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    • 2001
  • For the life evaluating of notched members, it is the best way that performing the real fatigue test of structure containing notch. But this method required generally much times and costs to evaluate fatigue life. So, generally we use the modified S-N curve or several methods to predict fatigue life. In this study, crack initiation life was evaluated by fatigue testing the SAE keyhole specimen and smooth specimen made of Al 7075-T6 alloys using the constant load then obtained S-N curve of smooth specimen and P-N curve of SAE keyhole specimen. And, fatigue lives of keyhole specimen are predicted using some life prediction methods (Nominal range I method, Nominal range II method, FEM analysis) for investigating experimented results, and that were compared with experimental data. Predicted fatigue lives by FEM analysis were corresponded with experimental data between 1/3times and 3times on the whole, and predicted fatigue lives using modified S-N curve (Nominal range I method, Nominal range II method) were nonconservative compared with that of FEM analysis.

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A Study on the Evaluation of the Pipe Fracture Characteristic (I) (실배관 파괴특성 평가에 관한 연구 (I))

  • Park, Jae-Sil;Seok, Chang-Sung
    • Proceedings of the KSME Conference
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    • 2001.06a
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    • pp.345-350
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    • 2001
  • In order to perform elastic-plastic fracture mechanical analyses, fracture resistance curves for concerned materials are required. 1T-CT specimen was used to obtain fracture resistance curves. But the fracture resistance curve by the 1T-CT specimen was very conservative to evaluate the integrity of the structure. And fracture resistance curve was affected by the specimen geometry and crack plane orientation. The objective of this paper is to be certain the conservativeness of the fracture resistance curve by the 1T-CT specimen and to provide the additional safety margin. For these, the fracture tests using the real pipe specimen and standard 1T-CT specimen test were performed. 4-point bending jig was manufactured for pipe test and direct current potential drop method was used to measure the crack extension and length for pipe test. From the pipe and the 1T-CT specimen test results, it was observed that the J-integral of the 1T-CT specimen test at the crack initiation point was very small compare to that of the pipe specimen test.

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A VANISHING THEOREM FOR REDUCIBLE SPACE CURVES AND THE CONSTRUCTION OF SMOOTH SPACE CURVES IN THE RANGE C

  • Ballico, Edoardo
    • Communications of the Korean Mathematical Society
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    • v.34 no.1
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    • pp.105-111
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    • 2019
  • Let $Y{\subset}{\mathbb{P}}^3$ be a degree d reduced curve with only planar singularities. We prove that $h^i({\mathcal{I}}_Y(t))=0$, i = 1, 2, for all $t{\geq}d-2$. We use this result and linkage to construct some triples (d, g, s), $d>s^2$, with very large g for which there is a smooth and connected curve of degree d and genus g, $h^0({\mathcal{I}}_C(s))=1$ and describe the Hartshorne-Rao module of C.

ESTIMATES FOR SCHRÖDINGER MAXIMAL OPERATORSALONG CURVE WITH COMPLEX TIME

  • Niu, Yaoming;Xue, Ying
    • Journal of the Korean Mathematical Society
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    • v.57 no.1
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    • pp.89-111
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    • 2020
  • In the present paper, we give some characterization of the L2 maximal estimate for the operator Pta,γf(Γ(x, t)) along curve with complex time, which is defined by $$P^t_{a,{\gamma}}f({\Gamma}(x,t))={\displaystyle\smashmargin{2}{\int\nolimits_{\mathbb{R}}}}\;e^{i{\Gamma}(x,t){\xi}}e^{it{\mid}{\xi}{\mid}^a}e^{-t^{\gamma}{\mid}{\xi}{\mid}^a}{\hat{f}}({\xi})d{\xi}$$, where t, γ > 0 and a ≥ 2, curve Γ is a function such that Γ : ℝ×[0, 1] → ℝ, and satisfies Hölder's condition of order σ and bilipschitz conditions. The authors extend the results of the Schrödinger type with complex time of Bailey [1] and Cho, Lee and Vargas [3] to Schrödinger operators along the curves.

A Clinical Study on Diagnosis of the patients with Scoliosis by D.I.T.I. (D.I.T.I.를 이용한 척추측만증 진단의 임상적 고찰)

  • Bae, Eun-jung;Seo, Jung-chul;Lim, Sung-chyl;Han, Sang-won
    • Journal of Acupuncture Research
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    • v.21 no.1
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    • pp.51-58
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    • 2004
  • Objective: The purpose of this study is to report that D.I.T.I. can be used for diagnosis of scoliosis. Methods: We measured the posterior trunk surface of the patients with shoulder pain or low back pain. They were ruled out as scoliosis by D.I.T.I. and compared with X-ray finding of T L-spine Ap views and calculated scoliosis angle. Results: In according to the spinoprocess curve in D.I.T.I. we could rule out as scoliosis. Thermal difference of left and right segmental areas of the patients was showed. Scoliosis angle of the patients ranged from $4^{\circ}$ to $11^{\circ}$ in X-ray finding. Conclusions: The results suggest that D.I.T.I. can explain physiologic and functional abnormalities than X-ray, in diagnosis of scoliosis. But further studies are required to for the diagnosis of scoliosis by analysing D.I.T.I..

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Cyclic compressive loading-unloading curves of brick masonry

  • AlShebani, Milad M.;Sinha, S.N.
    • Structural Engineering and Mechanics
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    • v.9 no.4
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    • pp.375-382
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    • 2000
  • Experimental investigation into the cyclic behaviour of sand plast brick masonry was performed on forty two square panels. The panels were subjected to cyclic uniaxial compression for two cases of loading: normal to bed joint and parallel to bed joint. Experimental data were used to plot the unloading-reloading curves for the entire range of the stress-strain curve. Mathematical expressions to predict the reloading and unloading stress-strain curves at various values of residual strain are proposed. A simple parabola and an exponential type formula are found adequate to model the unloading and reloading curves respectively. The models account for the potential effects of residual strain on these curves. Comparison of test results with the proposed mathematical expression shows good correspondence.

Real Time Scale Measurement of Inorganic Phosphate Release by Fluorophore Labeled Phosphate Binding Protein (형광단이 붙어 있는 인산결합 단백질에 의한 인산 배출의 실시간 측정)

  • Jeong Yong-Joo
    • Journal of Life Science
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    • v.15 no.6 s.73
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    • pp.935-940
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    • 2005
  • Fluorescence change of coumarin labeled phosphate binding protein (PBP-MDCC) was monitored to measure the amount of released inorganic phosphate ($P_{i}$) during nucleoside triphosphate (NTP) hydrolysis reaction. After purification of PBP-MDCC, fluorescence emission spectra showed that fluorescence responded linearly to $P_{i}$ up to about 0.7 molar ratio of $P_{i}$ to protein. The correlation of fluorescence signal and $P_{i}$ standard was measured to obtain [$P_{i}$] - fluorescence intensity standard curve on the stopped-flow instrument. When T7 bacteriophage helicase, double-stranded DNA unwinding enzyme using dTTP hydrolysis as an energy source, reacted with dTTP, the change of fluorescence was able to be converted to the amount of released $P_{i}$ by the $P_{i}$ standard curve. $P_{i}$ release results showed that single-stranded Ml3 DNA stimulated dTTP hydrolysis reaction several folds by T7 helicase. Instead of end point assay in NTP hydrolysis reaction, real time $P_{i}$-release assay by PBP-MDCC was proven to be very easy and convenient to measure released $P_{i}$.

Ferroelectric Properties of Ti-Doped and W-Doped SBT Ceramics (Ti와 W이 첨가된 SBT 세라믹스의 강유전 특성)

  • 천채일;김정석
    • Journal of the Korean Ceramic Society
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    • v.41 no.5
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    • pp.401-405
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    • 2004
  • Undoped SrB $i_2$T $a_2$O$_{9}$, donor-doped Sr$_{0.99}$B $i_2$(Ta$_{0.99}$W$_{0.01}$)$_2$O$_{9}$ and acceptor-doped SrB $i_2$(Ta$_{0.99}$Ti$_{0.01}$)$_2$O$_{8.99$ ceramics were prepared and their microstructure, ferroelectric P-E hysteresis and Curie temperature were investigated. Grain size did not influence P-E hysteresis curve in undoped SrB $i_2$T $a_2$O$_{9}$ ceramics. Donor-Doped Sr$_{0.99}$B $i_2$(Ta$_{0.99}$W$_{0.01}$)$_2$O$_{9}$ ceramics showed more saturated P-E hysteresis curve with larger remanent polarization (P$_{r}$) than undoped SrB $i_2$T $a_2$O$_{9}$ ceramics while acceptor-doped SrB $i_2$(Ta$_{0.99}$Ti$_{0.01}$)$_2$O$_{8.99}$ ceramics led to a pinched P-E hysteresis loop. Larger polarization in donor-doped Sr$_{0.99}$B $i_2$(Ta$_{0.99}$W$_{0.01}$)$_2$O$_{9}$ ceramics resulted from easier domain wall motion by Sr-vacancies.