• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제5권1호
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• pp.1-10
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• 2002

목적: 소아기는 알코올이나 약물 등에 의한 자극이 거의 없는 시기로 H. pylori 감염의 자연 경과와 단기간의 영향을 연구하기에 적합한 시기이다. 최근 H. pylori 감염의 기전으로 중요시되고 있는 위상피세포 증식과 세포사에 대해 소아에서 알아보고자 하였다. 방법: 1996년 5월부터 2001년 6월까지 이화여자대학교 목동병원 소아과에서 소화기 증상으로 내시경을 시행하여 H. pylori 감염으로 진단된 58예와 감염 음성 40예를 대상으로 하였다. H. pylori 감염 양성은 조직학적으로 H. pylori 균이 관찰되고, CLO 검사와 ureC PCR이 전부 양성인 경우로 하였다. 위생검 조직에서 개정된 시드니 체계를 이용하여 조직 소견을 분석하고, proliferating cell nuclear antigen (PCNA) 발현으로 위 상피세포 증식의 정도를, in situ terminal deoxynucleotidyl transferasemediated dUTP nick-end labeling (TUNEL) 방법으로 세포사의 정도를 조사하였다. 결과: 1) H. pylori 감염 양성에서 다핵형 중성구의 활동성(P=0.000), 만성 염증(P=0.000), 상피손상(P=0.000), 림프여포(P=0.000)의 정도가 감염 음성에 비하여 유의하게 높았다. H. pylori 감염 양성에서 장형화생은 관찰되지 않았다. 2) H. pylori 감염 양성에서 세포 증식 지표는 $67.8{\pm}18.13$으로, 음성 $54.8{\pm}14.46$에 비하여 유의하게 높았다(P=0.000). 세포 증식 지표는 H. pylori 밀도가 증가할수록(r=0.277, P=0.007), 다핵형 중성구의 활동성이 증가할수 (r=0.280, P=0.007), 만성염증이 증가할수록(r=0.284, P=0.006) 증가하였다. 3) 세포사 지표는 H. pylori 감염 양성에서 $0.44{\pm}0.447$, 음성에서 $0.14{\pm}0.196$으로 감염 양성에서 음성보다 유의하게 높았다(P=0.000). 세포사 지표는 H. pylori 밀도가 증가할수록(r=0.472, P=0.000), 다핵형 중성구의 활동성이 증가할수록(r=0.370, P=0.001), 만성 염증이 증가할수록(r=0.483, P=0.000) 증가하였다. 4) 세포 증식 지표가 증가할수록 세포사 지표는 유의하게 증가하였다(r=0.353, P=0.003). 결론: H. pylori 감염 소아에서 세포 증식 지표와 세포사 지표가 유의하게 증가하였으며 상관성도 유의하였다. 이는 소아에서 위 상피세포 증식과 세포사가 H. pylori의 병인에 중요함을 시사하며, 앞으로 세포 증식과 세포사의 기전, 유발 요인 외에 다른 병독 인자와의 관련성에 대한 연구가 필요하리라 생각된다.

• Bulletin of the Korean Chemical Society
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• 제20권1호
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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.

• 대한수학회보
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• 제55권2호
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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.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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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

• 한국환경보건학회지
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• 제3권1호
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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.

• 대한전자공학회논문지TC
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• 제45권6호
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• pp.27-33
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• 2008

차수가 h인 다항식 ${\hbar}(x){\in}F_q[x]$에서, $x-s_1,\;x-s_2,\;{\cdots},\;x-s_n$에 의해 생성된 $\(F_q[x]/({\hbar(x))\)*$의 multiplicative subgroup의 크기를 결정하는 것은 대단히 중요한 과제이다. 여기서 $\{s_1,\;s_2,\;{\cdots},\;s_n\}{\sebseteq}F_q$이고 모든 i 에 대해서, ${\hbar}(x){\neq}0$이다. 지금까지 알려진 asymptotic lower bound는 $(rh)^{O(1)}\(2er+O(\frac{1}{r})\)^h$이며, 여기서 $r=\frac{n}{h}$이고 e(=2.718...)는 natural logarithm의 기저이다. 본 논문에서는, coding theory 문제와 연계해서 더 낳은 lower bound인 $(rh)^{O(1)}\(2er+{\frac{e}{2}}{\log}r-{\frac{e}{2}}{\log}{\frac{e}{2}}+O{(\frac{{\log}^2r}{r})}\)^h$를 증명하고자 한다. 여기서 log는natural logarithm을 나타내며, 또한 이방식의 제약점에 대해서도 논의한다.

• 한국세라믹학회지
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• 제52권3호
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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.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book II
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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.

• 한국수소및신에너지학회논문집
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• 제20권6호
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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.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2005년도 전력전자학술대회 논문집
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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.