• 충청수학회지
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• 제22권3호
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• pp.579-586
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• 2009

Let $\varphi$ be a complete probability measure on $\mathbb{R}$, let $m_{\varphi}$ be the analogue of Wiener measure over paths on [0, T] and let f(t) be continuously differentiable on [0, T]. In this note, we give the analogue of Wiener measure $m_{\varphi}$ of {x in C[0, T]$\mid$x(0) < f(0) and $x(s_0){\geq}f(s_{0})$ for some $s_{0}$ in [0, T]} by use of integral equation techniques. This result is a generalization of Park and Paranjape's 1974 result[1].

• Korean Journal of Mathematics
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• 제19권3호
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• pp.309-319
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• 2011

We give sufficient conditions that the homogeneous differential equations : for $t{\geq}t_0$(> 0), $$x^{{\prime}{\prime}}(t)+q(t)x^{\prime}(t)+p(t)x(t)=0,\\x^{{\prime}{\prime}}(t)+q(t)x^{\prime}(t)+F(t,x({\phi}(t)))=0$$, are oscillatory where $0{\leq}{\phi}(t)$, 0 < ${\phi}^{\prime}(t)$, $\lim_{t\to{\infty}}{\phi}(t)={\infty}$. and $F(t,u){\cdot}sgn$ $u{\leq}p(t)|u|$. We obtain comparison theorems.

• 대한설비공학회지:설비저널
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• 제10권1호
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• pp.1-11
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• 1981

In this paper, a new performance equation of bath tubs has been derived, which is very characteristically illuminating and in good agreement with experiments : $$T=T_{\infty}+(T_0-T_{\infty})e-\frac{k(A'_f+A_0)}{Mc_{P{\Delta}x}t$$, where $T_{\infty}$ is the temperature of the bathroom, $T_0$ that of the bathwater at t=0, k the overall heat conductivity of the tub- wall, $A'_f$ the equivalent surface area to the wall, $A_0$ the submerged area of the tub-wall, M mass of the bath-water, $C_p$ the specific heat of the bathwater and ${\Delta}x$ the thickness of the tub-wall. Here the equivalent-free surface area is written as $$A'_f=mA_f,\;m=const.(1-{\phi})^{0.88}$$ : where m is a numerical factor which is determined by a simple experiment and some calculation, {\phi}$ the relative humidity and $A_f$ the real free-surface area. From this study, it has been clarified that cooling of bath-water is mainly due to mass-transfer through evaporation from the free surface and conductive heat loss through the tub-wall is minor, which rather gaily mock at common sense. The effect of keeping bathwater warn by increase of the tub-wall thickness is also analyzed by a new idea of the thickness gain factor.

• Journal of applied mathematics & informatics
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• 제12권1_2호
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• pp.429-436
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• 2003

We study the asymptotic equivalence between the nonlinear differential system $\chi$'(t) = f(t, $\chi$(t)) and its variational system ν'(t) = f$\chi$(t, 0)ν(t) by using the comparison principle and notion of strong stability.

• 대한후두음성언어의학회지
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• 제9권1호
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• pp.38-42
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• 1998

It has been reported that Tonsillectomy ＆ Adenoidectomy(T & A) resulted in the change of voice by structural changes directly to the vocal track. We studied the effect of T & A on the voice of patients comparing the pre-operative to the post-operative voice. It was performed using a Computerized Speech Lab(CSL50) which is currently used as a method for voice analysis. Forty-five patients who had T＆A, aging from 3 to 42 years old, took part in studies and wert evaluated for voice changes and the degree of formant changes of four basic vowels, /a/, /i/, /o/, and /u/. They were evaluated pre-operatively and post-operatively one month later using MDVP, CSL program of CSL50. The results obtained were as follows ; In using MDVP, there were some differences between pre-operative and post-operative shimmer measures within the normal range but other acoustic measures(Fo, jitter, NHR) show no significant differences(p>0.05). F3 of /a/ and /o/ were significantly decreased(p<0.05) and F2, F3 of /i/ were increased(p>0.05) in patients who only had Tonsillectomy in doing CSL spectrogram. For the patients who had T & A, Fl and F3 of /a/, F3 of /i/, Fl, F2 and F3 of /o/ were decreased with significant increase in F1 and F2 of /i/(p<0.05).

• 대한소아치과학회지
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• 제11권1호
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• pp.181-189
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• 1984

1,840 school children aged 6 to 13 years who live in inland area in CHOONG CHUNG BUK DO were surveyed epidemiologically on the dental caries prevalence. The results were as follows; 1. The prevalence of dental carries was 76.35 percentage in male, 76.15 percentage in female, and 76.25 percentage in both sexes. 2. d.m.f rate was 77.72 percentage in male, 80.07 percentage in female, and 78.86 percentage in both sexes. D.M.F rate was 30.73 percentage in male, 38.52 percentage in female, and 34.51 percentage in both sexes. 3. d.m.f.t. rate and index was 27.94 percentage,2.55T, and d.m.f.s. rate & index was 13.62 percentage, 6.22T. 4. D.M.F.T rate & index in permanent teeth was 4.86 percentage,0.72T, and D.M.F.S. rate & index was 1.20 percentage,0.89T. 5. The filling rate was 3.90 percentage in decidious teeth, 2,00 percentage in permanent teeth.

• 대한수학회보
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• 제56권1호
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• pp.1-12
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• 2019

For a finite poset $P=(X,{\preceq})$ the fractional weak discrepancy of P, denoted $wd_F(P)$, is the minimum value t for which there is a function $f:X{\rightarrow}{\mathbb{R}}$ satisfying (1) $f(x)+1{\leq}f(y)$ whenever $x{\prec}y$ and (2) ${\mid}f(x)-f(y){\mid}{\leq}t$ whenever $x{\parallel}y$. In this paper, we determine the range of the fractional weak discrepancy of (M, 2)-free posets for $M{\geq}5$, which is a problem asked in [9]. More precisely, we showed that (1) the range of the fractional weak discrepancy of (M, 2)-free interval orders is $W=\{{\frac{r}{r+1}}:r{\in}{\mathbb{N}}{\cup}\{0\}\}{\cup}\{t{\in}{\mathbb{Q}}:1{\leq}t<M-3\}$ and (2) the range of the fractional weak discrepancy of (M, 2)-free non-interval orders is $\{t{\in}{\mathbb{Q}}:1{\leq}t<M-3\}$. The result is a generalization of a well-known result for semiorders and the main result for split semiorders of [9] since the family of semiorders is the family of (4, 2)-free posets.

• 한국분무공학회지
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• 제28권3호
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• pp.143-149
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• 2023

Amidst the drive towards carbon neutrality, interest in renewable synthetic e-fuels is rising rapidly. These fuels, generated through the synthesis of atmospheric carbon and green hydrogen, offer a sustainable solution, showing advantages like high energy density and compatibility with existing infrastructure. The physical properties of e-fuels can be different from those of conventional gasoline based on manufacturing methods, which requires investigations into how the physical properties of e-fuels affect the fuel injection characteristics. This study performs a comparative analysis between conventional and Fischer-Tropsch (F-T) synthetic gasoline (e-gasoline) across various fuel temperatures, including the cold start condition. The fuel properties of F-T synthetic and conventional gasoline are analyzed using a gas chromatography-mass spectrometry technique and the injection rates are measured using a Bosch-tube injection rate meter. The F-T synthetic gasoline exhibited higher density and kinematic viscosity, but lower vapor pressure compared to the conventional gasoline. Both fuels showed an increase in injection rate as the fuel temperature decreased. The F-T synthetic gasoline showed higher injection rates compared to conventional gasoline regardless of the fuel temperature.

• Journal of Hospice and Palliative Care
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• 제7권1호
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• pp.8-16
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• 2004

목적: 본 연구는 자궁경부암 환자의 삶의 질을 파악하고, 질병 진행 단계와 치료 형태에 따른 삶의 질을 분석하는데 있다. 방법: 자료 수집은 3개의 종합병원에서 자궁경부암 환자 67명을 대상으로 하였으며, 자료수집 기간은 3월 15일부터 6월 4일까지 이었다. 연구 도구로는 Ferrell[18]의 삶의 질-암 환자용 도구(Quality of Life-cancer version)를 번역하여, 자궁경부암 환자에게 맞지 않는 4문항을 제외한 총 37문항으로 사용하였다. 자료 분석은 SPSS 통계프로그램을 이용하여, t-test, ANOVA, Scheffe test로 검증하였고 도구의 신뢰도 검증은 Cronbach's Alpha를 산출하였다. 결과: 자궁경부암 환자의 질병 진행 단계에 따른 삶의 질 정도는 유의한 차이가 있었다.(F=5.06, P=.003) 질병 진행 단계에 따른 영역별 삶의 질 정도에서는 신체적 안녕 영역(F=3.97 P=.012), 정신적 안녕 영역(F=3.91, P=.013), 사회적 안녕 영역(F=4.96, P=.004)에는 유의한 차이를 보였으나, 영적 안녕 영역(F=1.36, P=.262)은 유의한 차이를 보이지 않았다. 치료 형태에 따른 삶의 질정도는 유의한 차이를 보이지 않았다.(t=-1.83, P=.073) 치료 형태에 따른 영역별 삶의 질정도에서는 정신적 안녕 영역(t=-2.14, P=.037), 사회적 안녕 영역(t=-2.15, P=.036)에는 유의한 차이를 보였으나, 신체적 안녕 영역(t=-.93, P=.356), 영적 안녕 영역(t=.73, P=.469)에는 유의한 차이가 없었다. 결론: 자궁경부암 환자의 삶의 질은 질병 진행단계와 치료 형태 및 일반적 특성에 따라 차이가 있었다. 그러므로 자궁경부암 환자에게 질병 진행 단계와 치료 형태 및 일반적 특성을 고려한 간호 중재를 적용할 필요가 있다.

• 한국결정성장학회지
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• 제20권4호
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• pp.159-163
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• 2010

스컬용융법으로 큐빅지르코니아(YSZ) 단결정들($ZrO_2:Y_2O_3:Co_3O_4:CeO_2$=64:36:0.5:0~0.3mol%)을 성장시켜 $N_2$ 분위기 $1200^{\circ}C$에서 3시간 동안 열처리 하였다. 갈색의 단결정들은 각각 녹색 또는 청색으로 변화되었다. 열처리 전 후의 YSZ 단결정들은 직경 7, 두께 2 mm의 웨이퍼 또는 직경 12 mm의 라운드브릴리언트 컷으로 연마 하였다. 각 시편의 광학적 또는 구조적 특성은 UV-VIS 분광광도계와 XRD(X-ray diffraction)로 분석하였으며, $Ce^{3+}(^2F_{5/2},\;_{7/2}(4f){\rightarrow}^2T_g(5d^1))$, $Co^{2+}(^4A_2(^4F){\rightarrow}^4T_1(^4F)$ 또는 $^4T_1(^4P)$) 및 $Co^{3+}$에 의한 흡수, 이온화에너지 및 격자상수 변화를 확인하였다.