• 대한수학회지
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• 제48권3호
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• pp.655-667
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• 2011

A class of functions involving divided differences of the psi and tri-gamma functions and originating from Kershaw's double inequality are proved to be completely monotonic. As applications of these results, the monotonicity and convexity of a function involving the ratio of two gamma functions and originating from the establishment of the best upper and lower bounds in Kershaw's double inequality are derived, two sharp double inequalities involving ratios of double factorials are recovered, the probability integral or error function is estimated, a double inequality for ratio of the volumes of the unit balls in $\mathbb{R}^{n-1}$ and $\mathbb{R}^n$ respectively is deduced, and a symmetrical upper and lower bounds for the gamma function in terms of the psi function is generalized.

• 대한수학회지
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• 제45권2호
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• pp.559-573
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• 2008

In this paper, two classes of functions, involving a parameter and the classical Euler gamma function, and two functions, involving the classical Euler gamma function, are verified to be logarithmically completely monotonic in $(-\frac{1}{2},\infty)$ or $(0,\infty)$; some inequalities involving the classical Euler gamma function are deduced and compared with those originating from certain problems of traffic flow, due to J. Wendel and A. Laforgia, and relating to the well known Stirling's formula.

• 대한한의학회지
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• 제20권1호
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• pp.75-83
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• 1999

To investigate the effects of negative therapy at back meridian points on blood gas components and immune functions in male college students, this study was conducted on treatment types(abdomen group and back group) at three sampling times (before, post-2 wks and post-4 wks) by using $2{\times}3$ factoral design. Blood gas $components(pH,\;PCO_2,\;PO_2,\;HCO_3^-,\;O_2SAT,\;BE)$, red blood cell, hematocrit, hemoglobin, white blood cell and subsets(neutrophil, basophil, eosinophil. lymphocyte, monocyte), total T cells, helper T cells, suppressor T cells, Th/Ts ratio, total B cells, serum immunoglobulin levels (IgG, IgA, IgM, IgD, IgE), Cytokines(Interlukin$-1{\beta}$, -2, -4, 2 receptor, -6 and ${\gamma}$-interferon), NK cells were measured. Collected with data were analyzed statistically by repealed measured ANOVA. The pattern of change between two groups for hematocrit, hemoglobin, suppressor T cells, interleukin-6, ${\gamma}-interferon$, NK cells at post-2 weeks and BE, lymphocyte, basophil at post-4 weeks was significantly different(p<0.05) And also the pattern of change over time for ${HCO_3}^-$(2 wks vs 4 wks), WBC, neutrophil, lymphocyte(0 wks vs 2 wks and 2 wks vs 4 wks) was significantly different(p<0.05). In summary, these data suggest that negative therapy at back meridian points had an effect on blood gas components and immune functions in male college students because practicing negative therapy at back meridian points was not associated with changes of all blood gas components and immune factors but associated with changes of BE, hematocrit, hemoglobin, WBC. neutrophil, lymphocyte, interleukin-6. ${\gamma}-interferon$, NK cells.

• Journal of applied mathematics & informatics
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• 제30권1_2호
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• pp.219-234
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• 2012

By using the generalized Riccati transformation and the inequality technique, we establish some new oscillation criterion for the second-order nonlinear delay dynamic equations $$(a(t)(x^{\Delta}(t))^{\gamma})^{\Delta}+q(t)f(x({\tau}(t)))=0$$ on a time scale $\mathbb{T}$, here ${\gamma}{\geq}1$ is the ratio of two positive odd integers with $a$ and $q$ real-valued positive right-dense continuous functions defined on $\mathbb{T}$. Our results not only extend and improve some known results, but also unify the oscillation of the second-order nonlinear delay differential equation and the second-order nonlinear delay difference equation.

• 한국산림과학회지
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• 제102권4호
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• pp.477-483
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• 2013

본 연구의 목적은 몬테 카를로 시뮬레이션을 이용하여 소나무 탄소배출계수 자료의 확률밀도를 추정하고 불확도를 제시하는데 있다. 이용된 탄소배출계수는 목재기본밀도, 바이오매스확장계수, 뿌리함량비이고 4개의 확률밀도 함수(정규분포, 로그정규분포, 감마분포, 와이불 분포)를 고려하였다. 2-표본 콜모그로프-스미르노프 검정통계량과 누적밀도그림을 비교하여 최적의 확률밀도함수를 선정하고 상한과 하한의 불확도를 제시하였다. 본 연구의 결과에 의하면, 각 탄소배출계수에서 추정된 확률밀도함수는 강원지방소나무에서 목재기본밀도는 감마분포, 바이오매스확장계수는 로그정규분포, 뿌리함량비는 정규분포이고 중부지방소나무에서 목재기본밀도는 정규분포, 바이오매스확장계수는 감마분포, 뿌리함량비는 감마분포를 나타내었다. 강원지방소나무 탄소배출계수의 불확도는 상한에서 62.1%, 하한에서 -52.6%이고 중부지방소나무는 상한에서 43.9%, 하한에서 -34.5%를 나타내었다.

• Journal of Korean Vacuum Science & Technology
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• 제1권1호
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• pp.30-37
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• 1997

Interactions of Cu films with Si substrates separated by thin layers of molybdenum and molybdenum nitride were investigated in the viewpoint of diffusion barrier to copper. the diffusion barrier behavior of the layers was studied as functions of deposition and annealing conditions by cross-sectional transmission electron microscopy and Nomarski microscopy. the layers deposited at $N_2$ gas ratios of 0.4 and 0.5 exhibited good diffusion barrier behaviors up to $700^{\circ}C$, mainly due to the phase transformation of molybdenum to $\gamma$-Mo$_2$N phase. The increase in the N gas ratio in deposition elevates the lower limit of barrier failure temperature. Futhermore, amorphous molybdenum nitride films deposited at 20$0^{\circ}C$ and 30$0^{\circ}C$ did not fail, while the crystalline $\gamma$-Mo$_2$N films deposited at 40$0^{\circ}C$ and 50$0^{\circ}C$ showed signs of interlayer interactions between Cu and Si after annealing at 75$0^{\circ}C$ for 30 minutes. Therefore, the amorphous nature of the molybdenum nitride layer enhanced its ability to reduce Cu diffusion and its stability as a diffusion barrier at elevated temperatures.

• 한국지반공학회지:지반
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• 제14권5호
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• pp.39-52
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• 1998

본 논문은 정규압밀된 점성토 지반에서 강관 매입 말뚝의 수평 거동에 영향을 미치는 여러인자들 중에서 말뚝의 근입길이, 지반조건(건조단위 중량 $\gamma_4$), 말뚝 두부의 구속조건의 영향에 관하여 모형실험을 수행하였으며, 이러한 영향을 정량화 할 수 있는 경첩식을 그 결과들로부터 얻었다. 모형실험에 사용한 지반은 3종류의 정규압밀 점토이다. 2종류의 말뚝 근입길이와 말뚝 두부의 고정 자유조건의 모형실험결과들에 의하여 수평하중-변위 관계는 $\gamma_d/\gamma_{dmax}$=0.84 이하에서 완전 탄소성체의 거동형상을 보일 것으로 나타났으며, 각 실험에서 최대 수평하중(Q--) 이후의 수평하중 감소는 상당한 시간 의존성을 보였다. 본 연구에서는 수평 하중-변위관계(logo-logy/D)와 최대 휨 모멘트-변위관계($loaM_{max}$.-.-logy/D)에서 각각 구한 항복 수평하중(Qy)과 항복 최대 휭 모멘트(My)가 직선적인 관계로 밝혀졌다. Relaxation에 의한 수평하 중은 모형실험 결과들로부터 시간을 변수로 한 지수 함수식으로 회귀분석 하였다. 수평 극한하중과 항복하중에 대한 지반조건의 영향은 $\gamma_4$$/\gamma_{dmax}$의 변수로 한 지수함수식으로 모델화 하였으며, Broms와 Budhu et at.에 의한 결과와의 비교에서 예측결과가 26-78%정도 과대평가 되었다. 수평하중-변위 관계에 대한 말뚝 두부의 고정조건 영향에서 $Q_{mxed}/Q_{free}$-y/D의 관계는 상당히 비선형적으로 나타났으며, yiD를 변수로 한 지수함수식으로 모델화하였다.

• Nuclear Engineering and Technology
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• 제4권1호
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• pp.3-10
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• 1972

수정의 영형광 glow curve 상,"before glow"의 생성원인중의 하나가 밀폐된 제한 공간내의 산란 감마선의 기여임을 확인하기 위하여 산란선대 일차선의 기여비(S/P)를 측정하였다. 이 S/P와 "before glow"의 유효높이 ($h_{b}$)와의 상관 관계를 고찰하였는바 상관계수+0.9라는 비교적 밀접한 일차 관계가 있음을 알았으며 이는 에너지가 감소된 산란 선에 의하여 여기되었던 전자가 본래 일차선으로 여기되었던 전자보다 얕은 trap에 걸려 있었음을 입증하는 것으로 보인다. 한편 $h_{b}$와 glow curve의 전면적 (At)의 비 및 "before glow"의 유효면적(Ab)과 At 와의 비가 S/P와 어떤 관계에 있는가도 조사하였는데 이들의 관계는 단순하지 않으며 다만 S/P 값이 0.035 보다 큰 영역에서는 간단한 대수함수로 표현되었다. 끝으로 자연수정을 TLD로 사용할 경우 그 재사용을 위한 선량한계를 살펴본 결과 그것은 $10^{5}$ R 정도임을 알아내었다.

• 대한수의학회지
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• 제36권2호
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• pp.313-325
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• 1996

Experiments were undertaken to examine the ability of selenium to protect against alcohol and/or paraquat-induced hepatotoxicity and to examine the additive effect between alcohol and paraquat. Protective effect against hepatotoxic functions was measured in serum from alcohol(15% v/v), paraquat(200ppm), alcohol and paraquat, and combination of sodium selenite(4ppm) in drinking water-fed guinea pigs ad libitum for 4 weeks. A total of 68 healthy 7-weeks-old male animals were assigned at random to 8 treatment groups(9~13 animals/group). Body and liver weight losses, and high serum concentrations in aspartate aminotransferase(AST), alanine aminotransferase(ALT, in only paraquat group), $\gamma$-glutamyltranspeptidase($\gamma$-GTP), cholesterol(Cho), creatinine, blood urea nitrogen(BUN), total bilirubin(TB), direct bilirubin(DB), total protein(TP), albumin and globulin as well as low values in alkaline phosphatase(ALP) and glucose were produced in a groups of alcohol or paraquat-fed. These values were not potentiated in a group given the combination of alcohol plus paraquat. Morphological changes in the liver were also observed in the alcohol or paraquat-fed group. Lipid droplet and cell swelling in the hepatocytes were observed in alcohol-fed guinea pig, especially Mallory's hyaline arounded hepatic vein. In the paraquat-fed guinea pig, lipid droplet, pyknosis and karyolysis were observed. When alcohol or paraquat was combined with selenium-fed, hyperplasia of Kupffer cell in liver were observed. However, the mean ALT, $\gamma$-GTP, Cho, BUN, TB, TP, albumin and globulin values were lower in groups given the combination of alcohol and/or paraquat plus selenium, compared with groups given alcohol and/or paraquat. Also, the ratio of liver weight to body weight and ALP values(exception of paraquat plus selenium group) were increased by selenium. These results suggest that an adequate selenium confers marked protection against alcohol and paraquat-induced hepatotoxicity.

• Nutrition Research and Practice
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• 제9권2호
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• pp.192-198
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• 2015

BACKGROUND/OBJECTIVES: Vitamin E is a fat-soluble vitamin and functions primarily as a lipid antioxidant. Inadequate vitamin E status may increase risk of several chronic diseases. Thus, the objectives of this study were to estimate intake and plasma concentration of each tocopherol and to evaluate vitamin E status of Korean adults. SUBJECTS/METHODS: Three consecutive 24-h food recalls and fasting blood samples were collected from healthy 20- to 59-y-old adults (33 males and 73 females) living in the Seoul metropolitan area, South Korea. ${\alpha}$-, ${\beta}$-, ${\delta}$-, and ${\gamma}$-tocopherol intakes and plasma concentrations of tocopherols (${\alpha}$-, ${\delta}$-, and ${\gamma}$- tocopherol) were analyzed by gender. RESULTS: Dietary vitamin E and total vitamin E intake (dietary plus supplemental vitamin E) was $17.68{\pm}14.34$ and $19.55{\pm}15.78mg$ ${\alpha}$-tocopherol equivalents, respectively. The mean daily ${\alpha}$-tocopherol, and ${\gamma}$-tocopherol intakes were $3.07{\pm}2.27mg$ and $5.98{\pm}3.74mg$, respectively. Intakes of total vitamin E and each tocopherol of males were significantly higher than those of females (P < 0.05). Plasma ${\alpha}$-tocopherol concentration was $15.45{\pm}10.16$ of males and $15.00{\pm}4.54{\mu}mol/L$ of females, respectively. There were no significant differences in plasma tocopherol concentrations by gender ($P{\geq}0.05$). Plasma ${\alpha}$-tocopherol was negatively correlated with ${\gamma}$-tocopherol intake (P < 0.05). Twenty-three percent of the subjects had plasma ${\alpha}$-tocopherol concentrations < $12{\mu}mol/L$ indicating a biochemical deficiency of vitamin E. Approximately 8% and 9% of these participants had plasma ${\alpha}$-tocopherol:total lipid ratio less than $1.59{\mu}mol/mmol$ and plasma ${\alpha}$-tocopherol:total cholesterol ratio less than $2.22{\mu}mol/mmol$, respectively, which are also indicative of vitamin E deficiency. CONCLUSIONS: Vitamin E intakes of Korean adults were generally adequate with the Korean Dietary Reference Intakes for vitamin E. However, ${\alpha}$-tocopherol intake was lower than that reported in other countries, and 23% of the subjects in the current study were vitamin E deficient based on plasma ${\alpha}$-tocopherol concentrations.