• Title/Summary/Keyword: D-F/F

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KRONECKER FUNCTION RINGS AND PRÜFER-LIKE DOMAINS

  • Chang, Gyu Whan
    • Korean Journal of Mathematics
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    • v.20 no.4
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    • pp.371-379
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    • 2012
  • Let D be an integral domain, $\bar{D}$ be the integral closure of D, * be a star operation of finite character on D, $*_w$ be the so-called $*_w$-operation on D induced by *, X be an indeterminate over D, $N_*=\{f{\in}D[X]{\mid}c(f)^*=D\}$, and $Kr(D,*)=\{0\}{\cup}\{\frac{f}{g}{\mid}0{\neq}f,\;g{\in}D[X]$ and there is an $0{\neq}h{\in}D[X]$ such that $(c(f)c(h))^*{\subseteq}(c(g)c(h))^*$}. In this paper, we show that D is a *-quasi-Pr$\ddot{u}$fer domain if and only if $\bar{D}[X]_{N_*}=Kr(D,*_w)$. As a corollary, we recover Fontana-Jara-Santos's result that D is a Pr$\ddot{u}$fer *-multiplication domain if and only if $D[X]_{N_*} = Kr(D,*_w)$.

Study on the Analysis of Differential Pressure of the Access Door for a Smoke Control Zone and the Effectiveness of the Measurement Criteria of its Opening Force (제연구역 출입문의 차압 및 개방력 측정기준의 실효성 분석에 관한 연구)

  • Lee, Jae-Ou;Choi, Chung-Seog
    • Fire Science and Engineering
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    • v.26 no.4
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    • pp.24-30
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    • 2012
  • The purpose of this study is to analyze the problem in measuring the differential pressure between the fire area and the neighboring smoke control zone as well as the opening force of a fire door and to present the actual values measured by an objective method. NFSC 501A specifies that the force necessary to open an access door when operating a smoke control system shall be less than 110 N. When the smoke control system does not operate in the space where it is installed, the door opening force can be measured by the test method in KS F 2805. However, when the smoke control system operates, additional opening force is required to overcome the force generated by the differential pressure between the fire area and smoke control room. Therefore, it can be seen that the method proposed by the standard has insufficient reliability. The analog measuring device and digital measuring device showed that the opening forces, $F_a$ and $F_d$, of the fully closed door before the smoke control system were 27.8 N and 27.4 N, respectively. When the door remained open by $5^{\circ}$, the opening forces, $F_a$ and $F_d$, were 33 N and 33.6 N, respectively. When the smoke control system operated and the door was fully closed, the door opening forces, $F_a$ and $F_d$, were 77.6 N and 76.0 N, respectively. Therefore, since the door opening forces are different from the criteria presented by KS F 2805, it is required to review the criteria appropriately.

Segregation Mode of Plant Height in Crosses of Rice Cultivars Ⅸ. Crosses between Semi-dwarf Japonicas and Semi-dwarf(d-t) gene Testers (수도 품종간 교잡에 있어서 간장의 유전분리 Ⅸ. 단간 Japonica 품종과 Semi-dwarf (d-t) gene 검정친과의 조합)

  • Kim, Yong-Kwon;Kim, Hong-Yeol;Nam, Yeong-Woo;Park, Sun-Zik;Heu, Mun-Hue
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.30 no.4
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    • pp.449-454
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    • 1985
  • In order to search for the semi-dwarf japonica varieties allelic to the semi-dwarf rice cultivar which is controlled by d-t gene, seven dwarf japonica varieties. Reimei, Hoyoku. Shiranui, Kokumasari, M 7. S.224 and S.295 were crossed to the semi-dwarf cultivar, wx 817. wx 817 is known to have semi-dwarf gene d-t. Their F$_1$, F$_2$ and F$_3$ were grown in 1984 and 1985 and culm lengths were measured at harvest. The results are summarized as follows. 1. The F$_2$s of all 7 cross combinations showed normal distribution and no segregation. 2. The range of culm length variation in the F$_3$ was variable depending on the cross combination, but the general pattern was similar in the all 7 crosses. 3. The mean of F$_3$ and parental F$_2$ mean which were selected into short, medium and tall groups were similar and showed no segregation, implying the selection efficiency in F$_2$. 4. From the results of F$_2$ and F$_3$ segregations, it is concluded that the culm length of the 7 semi-dwarf japonicas tested here are controlled by the same major gene d-t although they are modified by different minor genes.

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A Research on Subjective Symptoms of Fatigue of Housewives at Shin-Chon Area in Seoul (피로 자각증상표에 의한 일부 신촌지역 주부들의 피로도에 관한 일 연구)

  • 이광옥;신공범
    • Journal of Korean Academy of Nursing
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    • v.9 no.2
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    • pp.27-38
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    • 1979
  • This study was undertaken to determine the subjective symptoms of fatigue among the house-wives groups. Inquiries into subjective symptoms of fatigue were made by the form designied by the Industrial Fatigue Research Committee of the Japan Society of Industrial Health (1961), Comprising 30 items. These items are classified into 3 groups of 10 items, namely, A) Physical Symptoms, B) Mental Symptoms, C) Neuro-Sensory Symptoms (Figure 1 ). The results of the investigation can be summerized as follows: 1. Within the total items (T), the physical symptoms (A) were the strongest in the effect on the feelings of fatigue, and were followed by (B), and (C). 2. There was a significant difference shown in the distribution of responses by height (X$^2$=236.29, d.f. = 145, p < 0.00001). In the mental category (F = 2.22, d.f. = 4, p = 0.05) and neuro-sensory category (F = 2.64, d.f. = 4, p < 0.001), there was a difference in the responses’com-plaints by weight. 3. As for the ages, housewives at the age of 50 presented a higher rate than those 30 or 20. 4. Regarding the number of children, respondents have more children showed higher frequency rate of complaints. 5. In the investigation sample, complaints were related to education level (f = 18.34, d.f. = 3, p<0.0001) pentruation (t = 2.31, p< 0.022), and sleeping hours (F = 6.04, d.f. = 6, p< 0.0001).

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N-(4-[$^{18}F$]Fluoromethylbenzyl)spiperone : A Selective Radiotracer for In Vivo Studies of Dopamine $D_2$ Receptors (N-(4-[$^{18}F$Fluoromethylbenzyl)spiperone : 유력한 도파민 $D_2$ 수용체 선택성 방사성리간드)

  • Kim, Sang-Eun;Choe, Yearn-Seong;Chi, Dae-Yoon;Lee, Kyung-Han;Choi, Yong;Kim, Byung-Tae
    • The Korean Journal of Nuclear Medicine
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    • v.31 no.4
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    • pp.421-426
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    • 1997
  • We evaluated the in vivo kinetics, distribution, and pharmacology of N-(4-[$^{18}F$]fluoromethylbenzyl)spiperone ([$^{18}F$]FMBS), a newly developed derivative of spiperone, as a potentially more selective radiotracer for the dopamine (DA) $D_2$ receptors. Mice received 1.9-3.7 MBq (1.8-3.6 nmol/kg) of [$^{18}F$]FMBS by tail vein injection. The time course and regional distribution of the tracer in brain were assessed. Blocking studies were carried out by intravenously preinjecting DA $D_2$ receptor blockers (spiperone, butaclamol) as well as drugs with high affinity for DA $D_1$ (SCH 23390), DA transporter (GBR 12909), and serotonin $S_2$ ($5-HT_2$) (ketanserin) sites. After injection of the tracer, the radioactivity in striatum increased steadily over time, resulting in a striatal-to-cerebellar ratio of 4.8 at 120 min postinjection. By contrast, the radioactivity in cerebellum, frontal cortex, and remaining cortex washed out rapidly. Preinjection of unlabeled FMBS (1 mg/kg) and spiperone (1 mg/kg) reduced [$^{18}F$]FMBS striatal-to-cerebellar ratio by 41% and 80%, respectively. (+)-Butaclamol (1 mg/kg) blocked 80% of the striatal [$^{18}F$]FMBS binding, while (-)-butaclamol (1 mg/kg) did not. Preinjection of SCH 23390 (1 mg/kg) and GBR 12909 (5 mg/kg) had no significant effect on [$^{18}F$]FMBS binding. Ketanserin (1 mg/kg), a ligand for the $5-HT_2$ receptors, did not cause significant inhibition either in striatum, in frontal cortex, or the remaining cortex. The results demonstrate that [$^{18}F$]FMBS labels DA $D_2$ receptors selectively in vivo in the mouse brain. It may hold promise as a selective radiotracer for studying DA $D_2$ receptors in vivo by PET.

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ON FARTHEST POINTS IN METRIC SPACES

  • Narang, T.D.
    • The Pure and Applied Mathematics
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    • v.9 no.1
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    • pp.1-7
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    • 2002
  • For A bounded subset G of a metric Space (X,d) and $\chi \in X$, let $f_{G}$ be the real-valued function on X defined by $f_{G}$($\chi$)=sup{$d (\chi, g)\in:G$}, and $F(G,\chi)$={$z \in X:sup_{g \in G}d(g,z)=sup_{g \in G}d(g,\chi)+d(\chi,z)$}. In this paper we discuss some properties of the map $f_G$ and of the set $ F(G, \chi)$ in convex metric spaces. A sufficient condition for an element of a convex metric space X to lie in $ F(G, \chi)$ is also given in this pope.

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NORMAL FAMILIES OF MEROMORPHIC FUNCTIONS WITH MULTIPLE VALUES

  • Li, Yuntong;Liu, Zhixiu
    • Bulletin of the Korean Mathematical Society
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    • v.54 no.2
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    • pp.593-605
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    • 2017
  • In this paper, we consider some normality criteria concerning multiple values. Let $\mathcal{F}$ be a family of meromorphic functions defined in a domain D. Let k be a positive integer and ${\psi}(z){\not\equiv}0$, ${\infty}$ be a meromorphic function in D. If, for each $f{\in}\mathcal{F}$ and $z{\in}D$, (1) $f(z){\neq}0$, and all of whose poles are multiple; (2) all zeros of $f^{(k)}(z)-{\psi}(z)$ have multiplicities at least k + 3 in D; (3) all poles of ${\psi}(z)$ have multiplicities at most k in D, then $\mathcal{F}$ is normal in D.

PULSATIONAL CHARACTERISTICS OF $\delta$ SCUTI VARIABLE HR1170

  • Kim, Seoung-Li;Lee, See-Woo
    • Journal of The Korean Astronomical Society
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    • v.23 no.1
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    • pp.1-13
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    • 1990
  • New uvby photoelectric photometry was carried out for a $\delta$ Scuti variable, HR1170. By applying the Fourier method and the linear least square method, three frequencies were derived: $f_1=10.06134c/d$ ($P_1=0.^d0994$). $f_2=11.91754c/d$ ($P_2=0.^d0839$). $f_3=18.96776c/d$ ($P_3=0.^d0527$). From the observed pulsational constants and from the phase difference and amplitude ratios for color(b-y) and magnitude y. three different pulsation modes (n, l) of $f_1(0,0)$, $f_2(1,2)$, $f_3(3,2)$ are deduced, indicating the existence of nonradial mode in HR1170. Some physical parameters indicate that HR1170 is evolving at the stage of H-shell burning.

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LEONARD PAIRS OF RACAH AND KRAWTCHOUK TYPE IN LB-TD FORM

  • Alnajjar, Hasan
    • Communications of the Korean Mathematical Society
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    • v.34 no.2
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    • pp.401-414
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    • 2019
  • Let ${\mathcal{F}}$ denote an algebraically closed field with characteristic not two. Fix an integer $d{\geq}3$, let $Mat_{d+1}({\mathcal{F}})$ denote the ${\mathcal{F}}$-algebra of $(d+1){\times}(d+1)$ matrices with entries in ${\mathcal{F}}$. An ordered pair of matrices A, $A^*$ in $Mat_{d+1}({\mathcal{F}})$ is said to be LB-TD form whenever A is lower bidiagonal with subdiagonal entries all 1 and $A^*$ is irreducible tridiagonal. Let A, $A^*$ be a Leonard pair in $Mat_{d+1}({\mathcal{F}})$ with fundamental parameter ${\beta}=2$, with this assumption there are four families of Leonard pairs, Racah, Hahn, dual Hahn, Krawtchouk type. In this paper we show from these four families only Racah and Krawtchouk have LB-TD form.

THE LATTICE DISTRIBUTIONS INDUCED BY THE SUM OF I.I.D. UNIFORM (0, 1) RANDOM VARIABLES

  • PARK, C.J.;CHUNG, H.Y.
    • Journal of the Korean Mathematical Society
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    • v.15 no.1
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    • pp.59-61
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    • 1978
  • Let $X_1$, $X_2$, ${\cdots}$, $X_n$ be i.i.d. uniform (0,1) random variables. Let $f_n(x)$ denote the probability density function (p.d.f.) of $T_n={\sum}^n_{i=1}X_i$. Consider a set S(x ; ${\delta}$) of lattice points defined by S(x ; ${\delta}$) = $x{\mid}x={\delta}+j$, j=0, 1, ${\cdots}$, n-1, $0{\leq}{\delta}{\leq}1$} The lattice distribution induced by the p.d.f. of $T_n$ is defined as follow: (1) $f_n^{(\delta)}(x)=\{f_n(x)\;if\;x{\in}S(x;{\delta})\\0\;otherwise.$. In this paper we show that $f_n{^{(\delta)}}(x)$ is a probability function thus we obtain a family of lattice distributions {$f_n{^{(\delta)}}(x)$ : $0{\leq}{\delta}{\leq}1$}, that the mean and variance of the lattice distributions are independent of ${\delta}$.

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