• Title/Summary/Keyword: H&R

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Synthesis and Characterization of Group 13 Compounds of 2-Acetylpyridine Thiosemicarbazone. Single-Crystal Structure of $(iC_4H_9)-2Al(NC_5H_4C(CH_3)$NNC(S)NHPh)

  • 강영진;강상옥;고재정;손정인
    • Bulletin of the Korean Chemical Society
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    • v.20 no.1
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    • pp.65-68
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    • 1999
  • Novel mononuclear group 13 metal complexes with the formula (R2M){NC5H4C(CH3)NNC(S)NH(C6H5)} (M=Al, R=iC4H9 (1); M=Ga, R=iC4H9 (2); M=Al, R=CH2SiMe3 (3); M=Ga, R=CH2SiMe3 (4)) result when 2-acetyl pyridine 4-phenyl-thiosemicarbazone ligand is mixed with trialkyl aluminum or trialkylgallium. These compounds 1-4 are characterized by microanalysis, NMR (1H, 13C) spectroscopy, mass spectra, and singlecrystal X-ray diffraction. X-ray single-crystal diffraction analysis reveals that 1 is mononuclear metal compound with coordination number of 5 and N, N, S-coordination mode.

KRULL DIMENSION OF HURWITZ POLYNOMIAL RINGS OVER PRÜFER DOMAINS

  • Le, Thi Ngoc Giau;Phan, Thanh Toan
    • Bulletin of the Korean Mathematical Society
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    • v.55 no.2
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    • pp.625-631
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    • 2018
  • Let R be a commutative ring with identity and let R[x] be the collection of polynomials with coefficients in R. There are a lot of multiplications in R[x] such that together with the usual addition, R[x] becomes a ring that contains R as a subring. These multiplications are from a class of functions ${\lambda}$ from ${\mathbb{N}}_0$ to ${\mathbb{N}}$. The trivial case when ${\lambda}(i)=1$ for all i gives the usual polynomial ring. Among nontrivial cases, there is an important one, namely, the case when ${\lambda}(i)=i!$ for all i. For this case, it gives the well-known Hurwitz polynomial ring $R_H[x]$. In this paper, we completely determine the Krull dimension of $R_H[x]$ when R is a $Pr{\ddot{u}}fer$ domain. Let R be a $Pr{\ddot{u}}fer$ domain. We show that dim $R_H[x]={\dim}\;R+1$ if R has characteristic zero and dim $R_H[x]={\dim}\;R$ otherwise.

Development of 40 inch Full Color AMOLED Display

  • Chung, K.;Huh, J.M.;Sung, U.C.;Chai, C.C.;Lee, J.H.;Kim, H.;Lee, S.P.;Goh, J.C.;Park, S.K.;Ko, C.S.;Koh, B.S.;Shin, K.J.;Choi, J.H.;Jung, J.H.;Kim, N.D.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07a
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    • pp.781-784
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    • 2005
  • We have developed technology to fabricate large-size active matrix organic light-emitting diode (AMOLED) displays with good color purity. Using these innovations, we have developed a 40inch diagonal WXGA AMOLED full color display. Because the TFT circuitry occupies a large portion of the pixel structure, an efficient white emission OLED is essential to integrate the device onto the active matrix backplane. The development of these technologies enables OLED displays to fulfill the requirements for larger size applications such as HDTVs

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An Observation on the Viability and pH of Lactobacillus casei isolated from Yakult. (유산균음과에서 분리한 Lactobacillus casei의 저장온도별 균수 및 pH의 경시적 변화 관찰)

  • 이용욱;이원창
    • Journal of Environmental Health Sciences
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    • v.3 no.1
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    • pp.1-3
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    • 1976
  • The authors studied the viability and pH of Lactobacillus casei which was isolated from the Yakult in terms of its storage temperature time(days). The following results have been obtained: (1) The viability test to Lactobacillus casei under storage in 4$\circ$C temperature condition in 35 days, has shown that the original population of $4.0\times 10^8$ organisms was decreased to $0.1\times 10^8$, under storage in 10$\circ$C temperature the organisms to $0.08\times 10^8$, in room temperature the organisms to $0.009\times 10^8$, and in 35$\circ$C temperature the organisms to $0.0009\times 10^8$. The correlation coefficient of storage period (days) and number of bacterial viability were significant as r=0.956(p<0.01) in 4$\circ$C, r=-0.999 (p<0.01) in 100C, r=0.975(p<0.01) in room temperature and r=-0.923(p<0.01) in 35$\circ$C. (2) The pH test to Lactobacillus casei unde.r storage in 4$\circ$C temperature condition for 35 days has shown that the original pH of 3.54 were acidified to 3.35, under storage in 10$\circ$C temperature the pH were acidified to 3.20, in room temperature the pH were acidified to 3.15, and in 35$\circ$C temperature the pH were acidified to 3.0. The correlation coefficient of variation of pH between storage period (days) and temperature were significant as r=-0.972(p<0.01) in 4$\circ$C, r=-0.922 (p<0.01) in 10$\circ$C, r=-0.963 (p<0.01) in room temperature and r=-0.953 in 35$\circ$C.

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On The Size of The Subgroup Generated by Linear Factors (선형 요소에 의해 생성된 부분그룹의 크기에 관한 연구)

  • Cheng, Qi;Hwang, Sun-Tae
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.45 no.6
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    • pp.27-33
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    • 2008
  • Given a polynomial ${\hbar}(x){\in}F_q[x]$ of degree h, it is an important problem to determine the size of multiplicative subgroup of $\(F_q[x]/({\hbar(x))\)*$ generated by $x-s_1,\;x-s_2,\;{\cdots},\;x-s_n$, where $\{s_1,\;s_2,\;{\cdots},\;s_n\}{\sebseteq}F_q$, and for all ${\hbar}(x){\neq}0$. So far the best known asymptotic lower bound is $(rh)^{O(1)}\(2er+O(\frac{1}{r})\)^h$, where $r=\frac{n}{h}$ and e(=2.718...) is the base of natural logarithm. In this paper, we exploit the coding theory connection of this problem and prove a better lower bound $(rh)^{O(1)}\(2er+{\frac{e}{2}}{\log}r-{\frac{e}{2}}{\log}{\frac{e}{2}}+O{(\frac{{\log}^2r}{r})}\)^h$, where log stands for natural logarithm We also discuss about the limitation of this approach.

Correlations between Electrical Properties and Process Parameters of Silicon Nitride Films Prepared by Low Temperature (100℃) Catalytic CVD

  • Noh, Se Myoung;Hong, Wan-Shick
    • Journal of the Korean Ceramic Society
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    • v.52 no.3
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    • pp.209-214
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    • 2015
  • Silicon nitride films were deposited at $100^{\circ}C$ by using the catalytic chemical vapor deposition technique. The source gas mixing ratio, $R_N=[NH_3]/[SiH_4]$, was varied from 10 to 30, and the hydrogen dilution ratio, $R_H=[H_2]/[SiH_4]$, was varied from 20 to 100. The breakdown field strength reached a maximum value at $R_N=20$ and $R_H=20$, whereas the resistivity decreased in the same sample. The relative permittivity had a positive correlation with the breakdown field strength. The capacitance-voltage threshold curve showed an asymmetric hysteresis loop, which became more squared as $R_H$ increased. The width of the hysteresis window showed a negative correlation with the slope of the transition region, implying that the combined effect of $R_N$ and $R_H$ overides the interface defects while creating charge storage sites in the bulk region.

Development of Novel Pyrone Derivative Retaining Retinoidal Anti-aging Activity with Low Skin Irritation

  • Rho, H.S;Kim, D.H;Kim, S.N;Kim, S.J;Chang, I.S;Kang, H.H;Lee, O.S
    • Proceedings of the SCSK Conference
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    • 2003.09b
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    • pp.184-191
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    • 2003
  • New pyranone derivative, 2-((3E)-4(2H, 3H, -benzo[3, 4-d] 1, 3-dioxolan-5-yl)-2-oxo-but-3-enyloxy)-5-hydroxy-4H-pyran-4-one (Seletinoid $G^{TM}$), was designed as a novel retinoid on the assumption that the pyranone ring may mimic the carboxylic acid moiety in retinoid structure. The enolic hydroxy of pyranone at five position was easily deprotonated to form an enolate. The role of enolate was similar to that of carboxylic acid. To evaluate the value of Seletinoid G as an anti-aging ingredient, various tests were performed for example inhibitory effect for MMP-l expression, anti-oxidative activity, procollagen synthesis in hairless mouse and primary skin irritation. The result of this study suggested that our new synthetic retinoid could be used as a safe material for anti-aging cosmetics.

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Performance Characteristics of a Cascade Refrigeration System with Internal Heat Exchanger using Carbon Dioxide (R744) and Propane (R290) (내부 열교환기 부착 $CO_2-C_3H_8$용 캐스케이드 냉동시스템의 성능 특성)

  • Son, Chang-Hyo
    • Transactions of the Korean hydrogen and new energy society
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    • v.20 no.6
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    • pp.526-533
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    • 2009
  • In this paper, cycle performance analysis of $CO_2-C_3H_8$ (R744-R290) cascade refrigeration system with internal heat exchanger is presented to offer the basic design data for the operating parameters of the system. The operating parameters considered in this study include subcooling and superheating degree and gas cooling pressure and evaporating temperature in the propane (R290) low temperature cycle and the carbon dioxide (R744) high temperature cycle. The main results were summarized as follows : The COP of cascade refrigeration system of $CO_2-C_3H_8$ (R744-R290) increases with the increasing subcooling degree, but decreases with the increasing superheating degree. The COP of cascade refrigeration system increases with the increasing evaporating temperature, but decreases with the increasing gas cooling pressure. Therefore, superheating and subcooling degree, compressor efficiency, evaporating temperature and gas cooling pressure of $CO_2-C_3H_8$ (R744-R290) cascade refrigeration system have an effect on the COP of this system.

Development of Variable Torque Inverter from $37{\sim}280[kW]$ to 280[kW] ($37{\sim}280[kW]$ VT 인버터 개발)

  • Kwon, B.H.;Kim, J.H.;Na, S.H.;Hong, C.O.;Lee, J.P.;Park, C.H.;Park, E.S.;Kim, K.M.;Yoon, H.M.;Lee, K.J.
    • Proceedings of the KIPE Conference
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    • 2005.07a
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    • pp.51-53
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    • 2005
  • This paper focuses on the power circuit section of newly developed LSIS inverter for the variable torque application and presents the detailed explanation on the power circuits as well as its application-specific functional performance.

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Pixel-based Skin Color Detection using the Ratio of H to R in Color Images (컬러 영상에서 HR비를 이용한 화소기반 피부색 검출)

  • Lee Byung Sun;Rhee Eun Joo
    • Journal of Information Technology Applications and Management
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    • v.12 no.1
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    • pp.231-239
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    • 2005
  • This paper describes a new algorithm for pixel-based skin color detection to differentiate human form in color images by the ratio of R to H. In order to detect skin color efficiently, we examine the distribution of the R, G and B color elements combining to constitute the skin color in various color images. It shows that R is located in a narrower area than G and B on the RGB color space. And skin color is more related to R than G and B. Meanwhile, when the color image is transformed to the HSI color space, the S is variously changed in accordance with skin colors. The I is changed in accordance with the quantity and angle of light. But the H is less influenced by other conditions except for color. On the basis of the aforementioned study, we propose that the threshold for skin color detection is decided by the ratio of R to H. The proposed method narrows down the range of threshold, detects more skin color and reduces mis-detection of skin color in comparison to detection by R or H. In experimentation. it shows that the proposed algorithm overcomes changes of brightness and color to detect skin color in color images.

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