• Title/Summary/Keyword: $E_b/N_t$

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Performance Analysis of DS/CDMA System Considering Specific Absorption Rate in the Human (인체에서의 전자파 흡수율을 고려한 DS/CDMA 시스템의 성능 분석)

  • 조광윤;강희곡;조성언;조성준
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
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    • 2000.11a
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    • pp.264-267
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    • 2000
  • 본 논문에서는 이동국의 안테나로부터 방사되는 전파의 일부가 인체에 흡수되므로써 기지국에서 수신되는 E$_{b}$ N$_{t}$의 감소에 대해 조사하였고, 감소된 E$_{b}$ N$_{t}$를 기준으로 하여 전파의 인체 흡수가 DS/CDMA BPSK 시스템의 성능에 미치는 영향을 분석하였다. 분석 결과, 인체에서의 흡수가 30[%]에서 40[%]로 증가할 때 기지국에서의 E$_{b}$ N$_{t}$, 값이 약 0.5 [dB] 정도 감소함을 알 수 있으며, 40 [%]에서 50[%]로 중가할 때에는 약 0.6 [dB] 정도 감소함을 알 수 있었다. 또한 시뮬레이션을 통해 사용자 수가 15 명일 때 약 2.5 [dB]의 E$_{b}$ N$_{t}$ 값에서 음성 서비스가 가능하다는 것을 알 수 있었다. 그리고 이러한 E$_{b}$ N$_{t}$ 값을 만족시키려면, 흡수율이 10 [%] 증가 할 때마다 안테나 방사 전력을 약 20 [mW] 이상 증가시켜야 한다는 것도 알아내었다. 것도 알아내었다.

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Effects on n-Alcohols on the Amino-Proton Chemical Shifts and on the Hindered Rotation about the N-C(O) Bond of Acetamide (아세트아미드의 아미노 양성자의 화학적 이동과 N-C(O) 결합주위의 부자유회전에 미치는 n-알코올 용매 효과)

  • Gwon, Sun Gi;Choe, Jong Ho;Choe, Yeong Sang;Yun, Chang Ju;Gwon, Dae Geun
    • Journal of the Korean Chemical Society
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    • v.34 no.6
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    • pp.509-516
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    • 1990
  • 1H-nmr chemical shifts and lineshapes of amino-protons of acetamide (AA) in n-alcohols were determined. The chemical shifts are discussed by the Reichardt's solvent polarity parameter, E$_{T}$(30). The following relationship between $\delta$obs and E$_{T}$(30) was obtained. ${\delta}_{obs}$ = ${\delta}_{o}$ + aE$_{T}$ (30) + b[E$_{T}$(30)]$^2$ where ${\delta}_{o}$ is the chemical shift of the solute in gaseous state or at $E_{T}$(30) = 0, a is a characteristic constant for the protons of AA in n-alcohol solutions and b is a constant for the solute (AA)-solvent (n-alcohols) interaction. The barrier of the hindered rotation about the N-C(O) bond in AA was obtained by analysis of the lineshapes of the amino-protons in AA. The behavior of the internal rotation as well as chemical shifts of the amino-protons in AA has been found to be closely related to the $E_{T}$(30) of n-alcohols.

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Assessment of In Vitro Oocyte Maturation in Two Gobiid Fish Species, Chasmichthys dolichognathus and Tridentiger trigonocephalus after Exposure to Benzo[a]pyrene

  • Hwang, In-Joon;Baek, Hea-Ja
    • Development and Reproduction
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    • v.15 no.3
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    • pp.223-230
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    • 2011
  • Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous environmental contaminants derived from incomplete combustion of carbons and crude oil. In this study, we investigated the effects of benzo[a]pyrene (B[a]P), a representative PAHs on in vitro sex steroid hormone production and germinal vesicle breakdown (GVBD) using isolated oocytes of longchin goby (Chasmichthys dolichognathus) and chameleon goby (Tridentiger trigonocephalus). Oocytes in diameters of 0.8-0.9 (end vitellogenic stage) and 0.9-1.0 mm (germinal vesicle migratory stage) from longchin goby and 0.5 mm (fully vitellogenic stage) from chameleon goby were used. In GVBD assay, B[a]P at 10 nM stimulated GVBD in the oocytes of 0.8-0.9 mm from longchin goby. B[a]P at 1 nM stimulated GVBD in the oocytes with diameter 0.5 mm from chameleon goby. In steroid production from oocytes of longchin goby, B[a]P at 100 nM decreased testosterone (T) production, B[a]P at 1,000 nM increased estraiol-17 (J (E2) production and 10 and 100 nM increased $17,20{\beta}$-dihydroxy-4-pregnen-3-one ($17{\alpha}20{\beta}P$) production in the oocytes with diameter 0.8-0.9 mm. B[a]P at 1,000 nM increased E2 production, 100 and 1,000 nM increased $17{\alpha}20{\beta}P$ production in the oocytes with diameter 0.9-1.0 mm. In steroid production of oocytes from chameleon goby, B[a]P at 1,000 nM increased $E_2$ production. B[a]P at 10 nM increased $17{\alpha}20{\beta}P$ production. In the ratio of $E_2$ to T ($E_2$/T), B[a]P at 100 and 1,000 nM increased $E_2$/T in the oocytes of longchin goby. B[a]P at 100 nM also increased $E_2$/T in the oocytes of chameleon goby. Taken together, these results suggest that B[a]P have not only weak estrogenic effects but progestogenic effects on oocyte maturation.

SYMBOLIC DYNAMICS AND UNIFORM DISTRIBUTION MODULO 2

  • Choe, Geon H.
    • Communications of the Korean Mathematical Society
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    • v.9 no.4
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    • pp.881-889
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    • 1994
  • Let ($X, \Beta, \mu$) be a measure space with the $\sigma$-algebra $\Beta$ and the probability measure $\mu$. Throughouth this article set equalities and inclusions are understood as being so modulo measure zero sets. A transformation T defined on a probability space X is said to be measure preserving if $\mu(T^{-1}E) = \mu(E)$ for $E \in B$. It is said to be ergodic if $\mu(E) = 0$ or i whenever $T^{-1}E = E$ for $E \in B$. Consider the sequence ${x, Tx, T^2x,...}$ for $x \in X$. One may ask the following questions: What is the relative frequency of the points $T^nx$ which visit the set E\ulcorner Birkhoff Ergodic Theorem states that for an ergodic transformation T the time average $lim_{n \to \infty}(1/N)\sum^{N-1}_{n=0}{f(T^nx)}$ equals for almost every x the space average $(1/\mu(X)) \int_X f(x)d\mu(x)$. In the special case when f is the characteristic function $\chi E$ of a set E and T is ergodic we have the following formula for the frequency of visits of T-iterates to E : $$ lim_{N \to \infty} \frac{$\mid${n : T^n x \in E, 0 \leq n $\mid$}{N} = \mu(E) $$ for almost all $x \in X$ where $$\mid$\cdot$\mid$$ denotes cardinality of a set. For the details, see [8], [10].

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Effects of n-Alcohols on the Amino-Proton Chemical Shift and on the Hindered Rotation About N-C (S) Bond of Thioacetamide (Thioacetamide의 아미노 양성자의 화학적 이동과 N-C (S) 결합 주위의 부자유 회전에 미치는 n-알코올 용매 효과)

  • Jong-Ho Choi;Young-Sang Choi;Chang-Ju Yoon
    • Journal of the Korean Chemical Society
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    • v.33 no.2
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    • pp.149-155
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    • 1989
  • 1H-nmr chemical shifts and lineshapes of amino-protons of thioacetamide in n-alcohols were determined. The chemical shifts are discussed by the Reichardt's solvent polarity parameter, $E_T(30)$. The following relationship between ${delta}_{obs}\;and\;E_T(30)$ was obtained, ${\delta}_{obs}=a{\cdot}E_T(30)+b{\cdot}(E_T(30))_2$ where a is a characteristic constant for the protons of thioacetamide in n-alcohol solutions and b is a constant for the solute(TA)-solvent (n-alcohols) interactions. The barrier of the hindered rotation about the N-C(S) bond in TA was obtained by analysis of the lineshape of the amino-protons in TA. The behavior of the hindered rotation as well as chemical shifts of the amino-protons in TA has been found to be closely related to the $E_T(30)$ of n-alcohols.

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Temperature Dependence of Excitonic Transitions in GaN Grown by MOCVD

  • Guangde Chen;Jingyu Lin;Hongxing Jiang;Kim, Jung-Hwan;Park, Sung-Eul
    • Journal of Photoscience
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    • v.7 no.1
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    • pp.27-30
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    • 2000
  • The Photoluminescence (PL) measurement results of a very good quality GaN sample grown by metalorganic chemical vapor deposition (MOCVD) are reported. The temperature dependences of peak position, emission intensity, and the full width at half maximum (FWHM) of free-exciton (FX) A and B are presented. Our results show the fast thermal quenching of FX transition intensities and predominantly acoustic phonon scattering of emission line broadening. The transition-energy-shift following the Varshni's empirical equation, and by using it to fit the data, E$\_$A1/(T) = 3.4861 eV -6.046 $\times$ 10$\^$-4/T$^2$ (620.3+ T) eV, E$\_$B1/(T) = 3.4928 eV -4.777 $\times$ 10$\^$-4/T$^2$ / (408.2+ T) eV and E$\_$A2/ = 3.4991 eV -4.426 $\times$ 10$\^$-4/ T$^2$ / (430.6+ T) eV for A(n=1), B(n=1), and A(n=2) are obtained respectively.

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APPROXIMATION OF COMMON FIXED POINTS OF NON-SELF ASYMPTOTICALLY NONEXPANSIVE MAPPINGS

  • Kim, Jong-Kyu;Dashputre, Samir;Diwan, S.D.
    • East Asian mathematical journal
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    • v.25 no.2
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    • pp.179-196
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    • 2009
  • Let E be a uniformly convex Banach space and K a nonempty closed convex subset which is also a nonexpansive retract of E. For i = 1, 2, 3, let $T_i:K{\rightarrow}E$ be an asymptotically nonexpansive mappings with sequence ${\{k_n^{(i)}\}\subset[1,{\infty})$ such that $\sum_{n-1}^{\infty}(k_n^{(i)}-1)$ < ${\infty},\;k_{n}^{(i)}{\rightarrow}1$, as $n{\rightarrow}\infty$ and F(T)=$\bigcap_{i=3}^3F(T_i){\neq}{\phi}$ (the set of all common xed points of $T_i$, i = 1, 2, 3). Let {$a_n$},{$b_n$} and {$c_n$} are three real sequences in [0, 1] such that $\in{\leq}\;a_n,\;b_n,\;c_n\;{\leq}\;1-\in$ for $n{\in}N$ and some ${\in}{\geq}0$. Starting with arbitrary $x_1{\in}K$, define sequence {$x_n$} by setting {$$x_{n+1}=P((1-a_n)x_n+a_nT_1(PT_1)^{n-1}y_n)$$ $$y_n=P((1-b_n)x_n+a_nT_2(PT_2)^{n-1}z_n)$$ $$z_n=P((1-c_n)x_n+c_nT_3(PT_3)^{n-1}x_n)$$. Assume that one of the following conditions holds: (1) E satises the Opial property, (2) E has Frechet dierentiable norm, (3) $E^*$ has Kedec -Klee property, where $E^*$ is dual of E. Then sequence {$x_n$} converges weakly to some p${\in}$F(T).

IDEMPOTENCE PRESERVING MAPS ON SPACES OF TRIANGULAR MATRICES

  • Sheng, Yu-Qiu;Zheng, Bao-Dong;Zhang, Xian
    • Journal of applied mathematics & informatics
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    • v.25 no.1_2
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    • pp.17-33
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    • 2007
  • Suppose F is an arbitrary field. Let ${\mid}F{\mid}$ be the number of the elements of F. Let $T_{n}(F)$ be the space of all $n{\times}n$ upper-triangular matrices over F. A map ${\Psi}\;:\;T_{n}(F)\;{\rightarrow}\;T_{n}(F)$ is said to preserve idempotence if $A-{\lambda}B$ is idempotent if and only if ${\Psi}(A)-{\lambda}{\Psi}(B)$ is idempotent for any $A,\;B\;{\in}\;T_{n}(F)$ and ${\lambda}\;{\in}\;F$. It is shown that: when the characteristic of F is not 2, ${\mid}F{\mid}\;>\;3$ and $n\;{\geq}\;3,\;{\Psi}\;:\;T_{n}(F)\;{\rightarrow}\;T_{n}(F)$ is a map preserving idempotence if and only if there exists an invertible matrix $P\;{\in}\;T_{n}(F)$ such that either ${\Phi}(A)\;=\;PAP^{-1}$ for every $A\;{\in}\;T_{n}(F)\;or\;{\Psi}(A)=PJA^{t}JP^{-1}$ for every $P\;{\in}\;T_{n}(F)$, where $J\;=\;{\sum}^{n}_{i-1}\;E_{i,n+1-i}\;and\;E_{ij}$ is the matrix with 1 in the (i,j)th entry and 0 elsewhere.

THERE ARE NO NUMERICAL RADIUS PEAK n-LINEAR MAPPINGS ON c0

  • Sung Guen Kim
    • Bulletin of the Korean Mathematical Society
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    • v.60 no.3
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    • pp.677-685
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    • 2023
  • For n ≥ 2 and a real Banach space E, 𝓛(nE : E) denotes the space of all continuous n-linear mappings from E to itself. Let Π (E) = {[x*, (x1, . . . , xn)] : x*(xj) = ||x*|| = ||xj|| = 1 for j = 1, . . . , n }. An element [x*, (x1, . . . , xn)] ∈ Π(E) is called a numerical radius point of T ∈ 𝓛(nE : E) if |x*(T(x1, . . . , xn))| = v(T), where the numerical radius v(T) = sup[y*,y1,...,yn]∈Π(E)|y*(T(y1, . . . , yn))|. For T ∈ 𝓛(nE : E), we define Nradius(T) = {[x*, (x1, . . . , xn)] ∈ Π(E) : [x*, (x1, . . . , xn)] is a numerical radius point of T}. T is called a numerical radius peak n-linear mapping if there is a unique [x*, (x1, . . . , xn)] ∈ Π(E) such that Nradius(T) = {±[x*, (x1, . . . , xn)]}. In this paper we present explicit formulae for the numerical radius of T for every T ∈ 𝓛(nE : E) for E = c0 or l. Using these formulae we show that there are no numerical radius peak mappings of 𝓛(nc0 : c0).

Photoluminance Properties of $Al_3GdB_4O_{12}$ Phosphors Activated by $Tb^{3+}$and $Eu^{3+}$ ($Tb^{3+}$$Eu^{3+}$로 활성화된 $Al_3GdB_4O_{12}$ 형광체의 발광특성)

  • 김기운;김성우;이임렬
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.11a
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    • pp.594-597
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    • 1999
  • The new green and red phosphors for PDP application activated by T $b^{3+}$ and E $u^{3+}$ were synthesized, and their photoluminance properties were investigated. It was found that the brightness of $Al_3$Gd $B_4$ $O_{12}$ :T $b^{3+}$ green phosphor under 147nm VUV irradiation was higher than that of commercial Z $n_2$ $SiO_4$:M $n^{2+}$ phosphor. But the emitting intensity of A1$_3$Gd $B_4$ $O^{12}$ :E $u^{3+}$ red phosphor was inferior to the commercial (Y,Gd)B $O_3$:E $u^{3+}$. $Al_3$Gd $B_4$ $O_{12}$ Phosphor had a strong excitation band at 160nm associated with the host absorption, and also the photoluminance excitation intensity of $Al_3$Gd $B_4$ $O_{12}$ :T $b^{3+}$ was higher than that of Z $n_2$ $SiO_4$:M $n^{2+}$, but the intensity of $Al_3$Gd $B_4$ $O_{12}$ :E $u^{3+}$ phosphor was smaller than (Y,Gd)B $O_3$:E $u^{3+}$ phosphor In the VUV range. C $e^{3+}$ co-doping in A1$_3$Gd $B_4$ $O^{12}$ :E $u^{3+}$ and substitution of $Al^{3+}$ by G $a^{3+}$ A1$_3$Gd $B_4$ $O^{12}$ :E $u^{3+}$ phosphor were tried, but they did not improved the optical property .d the optical property .ty .

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