• Title/Summary/Keyword: gamma transformation

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Driving Forces for γ→ε Martensitic Transformation of Fe-Mn Alloys (Fe-Mn 합금의 γ→ε 마르텐사이트변태에 필요한 구동력)

  • Lee, Young-Kook;Choi, Chong-Sool
    • Journal of the Korean Society for Heat Treatment
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    • v.9 no.4
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    • pp.243-251
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    • 1996
  • Dilatometric experiment and thermodynamic calculation have been performed to determine $M_s$, $A_s$ and driving forces for ${\gamma}{\rightarrow}{\varepsilon}$ martensitic transformation of Fe-Mn alloys. The transformation temperatures($M_s$, $A_s$, $T_o) were decreased with increasing manganese content and were newly formulated as a function of manganese content. Driving force for ${\gamma}{\rightarrow}{\varepsilon}$ martensitic transformation was increased from -75J/mole to -105J/mole with increasing manganese content from 15wt.% to 25wt.%. Transformation temperature hysteresis($A_s-M_s$) was also increased from 50K to 80K with increasing mangenese content from 15wt.% to 25wt.%. The small driving force(-75J/mole~-105J/mole) and small ${\Delta}T$(50K~80K) for ${\gamma}{\rightarrow}{\varepsilon}$ martensitic transformation indicated that Fe-Mn alloys behave like thermoelastic martensitic alloys : We would like to call them semi-thermoelastic martensitic alloys.

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Eddy Current Testing to Measure Transformation Ratios in Metal (와류탐상에 의한 금속의 변태율 측정)

  • Wee, Sang-Bong;Han, Min-Koo
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.824-827
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    • 1988
  • Eddy Current Sensor to Measure the ${\gamma}-{\alpha}$/ Transformation Ratio of Metal is Designed and Implemented. Experimental Results Regarding to Impedance Variation due to ${\gamma}-{\alpha}$ Transformation Ratio of Metal Under Room Temperature are Reported. It Was Found That the Impedance of Metal is Increased With Increasing ${\gamma}-{\alpha}$ Ratio.

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Histogram Equalization using Gamma Transformation (감마변환을 사용한 히스토그램 평활화)

  • Chung, Soyoung;Chung, Min Gyo
    • KIISE Transactions on Computing Practices
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    • v.20 no.12
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    • pp.646-651
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    • 2014
  • Histogram equalization generally has the disadvantage that if the distribution of the gray level of an image is concentrated in one place, then the range of the gray level in the output image is excessively expanded, which then produces a visually unnatural result. However, a gamma transformation can reduce such unnatural appearances since it operates under a nonlinear regime. Therefore, this paper proposes a new histogram equalization method that can improve image quality by using a gamma transformation. The proposed method 1) derives the proper form of the gamma transformation by using the average brightness of the input image, 2) linearly combines the earlier gamma transformation with a CDF (Cumulative Distribution Function) for the image in order to obtain a new CDF, and 3) to finally perform histogram equalization by using the new CDF. The experimental results show that relative to existing methods, the proposed method provides good performance in terms of quantitative measures, such as entropy, UIQ, SSIM, etc., and it also naturally enhances the image quality in visual perspective as well.

Transformation and Mutation of Bacillus licheniformis 9945a Producing ${\gamma}-Poly(glutamic\;acid)$ (${\gamma}-Poly(glutamic\;acid)$ 생산성 균주 Bacillus licheniformis 9945a의 형질전환 미 돌연변이 유도)

  • Chung, Wan-Seok;Ko, Young-Hwan
    • Applied Biological Chemistry
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    • v.40 no.3
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    • pp.173-177
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    • 1997
  • Bacillus licheniformis 9945a releases a natural ${\gamma}-poly(glutamic\;acid)({\gamma}-PGA)$ into fermentation broth and shows a mucoid phenotype on the solid agar medium. Transformation of mucoid cells of Bacillus species has not been simple and straightforward. The transpositional activity of Tn10 in B. licheniformis also has not been own either. Thus, a spontaneous non-mucoid derivative of the B. licheniformis was obtained first. Shuttle vector pHV1248 containing mini-Tn10 was introduced into the non-mucoid derivative by the method of protoplast transformation. The resulting transformant was reverted to the wild mucoid phenotype, and then mutated randomly with the mini-transposon by heat induction. Auxotrophs requiring arginine, lysine, or tryptophan were isolated by replica plating method. Southern blotting and DNA-DNA hybridzation analysis showed that these auxotrophs were generated by mini-Tn10 insertion into the chromosomal DNA. This method of transformation and mutation using pHV1248 would be useful for the generation of diverse mutants of B. licheniformis 9945a.(Received January 24,1997; accepted March 10, 1997)

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OSCILLATION OF SECOND ORDER SUBLINEAR NEUTRAL DELAY DYNAMIC EQUATIONS VIA RICCATI TRANSFORMATION

  • SETHI, ABHAY KUMAR
    • Journal of applied mathematics & informatics
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    • v.36 no.3_4
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    • pp.213-229
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    • 2018
  • In this work, we establish oscillation of the second order sublinear neutral delay dynamic equations of the form:$$(r(t)((x(t)+p(t)x({\tau}(t)))^{\Delta})^{\gamma})^{\Delta}+q(t)x^{\gamma}({\alpha}(t))+v(t)x^{\gamma}({\eta}(t))=0$$ on a time scale T by means of Riccati transformation technique, under the assumptions $${\displaystyle\smashmargin{2}{\int\nolimits^{\infty}}_{t_0}}\({\frac{1}{r(t)}}\)^{\frac{1}{\gamma}}{\Delta}t={\infty}$$, and ${\displaystyle\smashmargin{2}{\int\nolimits^{\infty}}_{t_0}}\({\frac{1}{r(t)}}\)^{\frac{1}{\gamma}}{\Delta}t$ < ${\infty}$, for various ranges of p(t), where 0 < ${\gamma}{\leq}1$ is a quotient of odd positive integers.

The Study of Analytical Chemistry of the Modification of Manganese Dioxide (Report Two). Quantitative Determination of ${\gamma}$-Manganese Dioxide by Differential Heating Curves (變態二酸化 망간의 分析化學的 硏究 (第二報). 示差熱曲線에 依한 ${\gamma}-MnO_2$의 定量法)

  • Chan Ho Kim
    • Journal of the Korean Chemical Society
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    • v.15 no.5
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    • pp.241-245
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    • 1971
  • Endothermic peak of transformation of ${\gamma}-MnO_2$ was obviously shown by differential heating curve in the present study, and the transformation temperature was different from other modification. ${\gamma}-MnO_2$ carried out to analyze exclusively, by means of the half area method in corresponding endothermic peak of differential heating curve. ${\alpha}-\;and\;{$beta}-MnO_2$ (Pyrolusite) containing in sample about 75% is interfered about ${\pm}$10% of the relative error, and while those of below 50% is interfered about ${\pm}$5%.

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On the Properties of $\gamma$-.$\varepsilon$ for $H_\infty$ Control by State Feedback and Computation of the Infimum of $H_\infty$ Norm

  • Tian, Dong;Ohta, Michio
    • 제어로봇시스템학회:학술대회논문집
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    • 1993.10b
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    • pp.562-565
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    • 1993
  • It is well known that H$_{\infty}$ control problem involves solving an algebraic Riccati equation which includes a pair of parameters (.gamma., .epsilon.). Focusing on .epsilon. the maximum of .epsilon.. We discuss in this paper about the properties between the H$_{\infty}$ norm of a trnsfer function matrix and the parameters(.gamma., .epsilon.). We can change the algebraic relattion between .gamma. and .epsilon. by the similarity transformation of a considered system and we can find a proper transformation to get a simple quadratic algebraic equation between .gamma. and .epsilon.. This relation provide the H$_{\infty}$ norm of a transfer function.on.

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A Control Chart for Gamma Distribution using Multiple Dependent State Sampling

  • Aslam, Muhammad;Arif, Osama-H.;Jun, Chi-Hyuck
    • Industrial Engineering and Management Systems
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    • v.16 no.1
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    • pp.109-117
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    • 2017
  • In this article, a control chart based on multiple dependent (or deferred) state sampling for the gamma distributed quality characteristic is proposed using the gamma to normal transformation. The proposed control chart has two pairs of control limits, which can be determined by considering the in-control average run length (ARL). The shift in the scale parameter of a gamma distribution is considered and the out-of-control ARL is evaluated. The performance of the proposed chart has been shown for different levels of the parameters of the proposed control chart. It is also shown that the proposed chart is better than the Shewhart chart in terms of ARLs. A case study with a real data has been included for the practical usage of the proposed scheme.

RICCATI TRANSFORMATION AND SUBLINEAR OSCILLATION FOR SECOND ORDER NEUTRAL DELAY DYNAMIC EQUATIONS

  • Tripathy, Arun Kumar
    • Journal of applied mathematics & informatics
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    • v.30 no.5_6
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    • pp.1005-1021
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    • 2012
  • This work is concerned with oscillation of the second order sublinear neutral delay dynamic equations of the form $$\(r(t)\;\((y(t)+p(t)y(a(t)))^{\Delta}\)^{\gamma}\)^{\Delta}+q(t)y^{\gamma}({\beta}(t))=0$$ on a time scale $\mathcal{T}$ by means of Riccati transformation technique, under the assumptions $\int^{\infty}_{t_0}\(\frac{1}{r(t)}\)^{\frac{1}{\gamma}}$ ${\Delta}t={\infty}$ and $\int^{\infty}_{t_0}\(\frac{1}{r(t)}\)^{\frac{1}{\gamma}}$ ${\Delta}t$ < ${\infty}$, where 0 < ${\gamma}{\leq}1$ is a quotient of odd positive integers.

Resveratrol enhances cisplatin-induced apoptosis in human hepatoma cells via glutamine metabolism inhibition

  • Liu, Zhaoyuan;Peng, Qing;Li, Yang;Gao, Yi
    • BMB Reports
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    • v.51 no.9
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    • pp.474-479
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    • 2018
  • Cisplatin is one of the most effective chemotherapeutic drugs used in the treatment of HCC, but many patients will ultimately relapse with cisplatin-resistant disease. Used in combination with cisplatin, resveratrol has synergistic effect of increasing chemosensitivity of cisplatin in various cancer cells. However, the mechanisms of resveratrol enhancing cisplatin-induced toxicity have not been well characterized. Our study showed that resveratrol enhances cisplatin toxicity in human hepatoma cells via an apoptosis-dependent mechanism. Further studies reveal that resveratrol decreases the absorption of glutamine and glutathione content by reducing the expression of glutamine transporter ASCT2. Flow cytometric analyses demonstrate that resveratrol and cisplatin combined treatment leads to a significant increase in ROS production compared to resveratrol or cisplatin treated hepatoma cells alone. Phosphorylated H2AX (${\gamma}H2AX$) foci assay demonstrate that both resveratrol and cisplatin treatment result in a significant increase of ${\gamma}H2AX$ foci in hepatoma cells, and the resveratrol and cisplatin combined treatment results in much more ${\gamma}H2AX$ foci formation than either resveratrol or cisplatin treatment alone. Furthermore, our studies show that over-expression of ASCT2 can attenuate cisplatin-induced ROS production, ${\gamma}H2AX$ foci formation and apoptosis in human hepatoma cells. Collectively, our studies suggest resveratrol may sensitize human hepatoma cells to cisplatin chemotherapy via gluta${\gamma}H2AX$mine metabolism inhibition.