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한국산 민물 새우류에 관한 생물학적 연구 1. 징거미의 상대 성장 (BIOLOGICAL STUDIES ON THE FRESHWATER SHRIMPS OF KOREA 1. Relative Growth of Macrobrachium nipponensis (de Haan))

  • 정경석
    • 한국수산과학회지
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    • 제3권1호
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    • pp.71-76
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    • 1970
  • 낙동강에서의 징거미 (M. nipponensis)의 상대 성장을 암수별로 조사한 결과 두흉갑장과 체장의 회귀 관계는 암수사이에 유의의 차가 없었으나 제2보각의 각절은 뚜렷한 차이가 있었고 그 회귀 관계는 다음과 같다. 1. 두흉갑장(X)과 체장(Y) : Y=2.68996X+1.14784 in female. Y=2.73121X+1.10827 in male 2. 두흉갑장(X)과 기절(Y) : Y=0.16910X-0.06422 in female Y=0.19410X-0.06075 in male 3. 두흉갑장(X)과 좌절(Y) : Y= 0.48524X-0.10812 in female. Y= 0.69052X-0.28616 in male 4. 두흉갑장(X)과 장절(Y) : Y=0.51217X-0.04088 in female. Y= 1.9792X-0.98258 in male 5. 두흉갑장(X)과 완절(Y) : Y=0.87701X-0.33919 in female. Y=2.00091X-1.64116 in male 6. 두흉갑장(X) 전절(Y) : Y= 1.04672 X-0.50727 in female. Y=2.67663X-2.40488 in male 7. 두흉갑장(X) 과 지절(Y) : Y=0.26366 X+0.15743 in female. Y=1.04866 X-0.67781 in male

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EVALUATION OF SOME CONDITIONAL WIENER INTEGRALS

  • Chang, Kun-Soo;Chang, Joo-Sup
    • 대한수학회보
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    • 제21권2호
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    • pp.99-106
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    • 1984
  • J. Yeh has recently introduced the concept of conditional Wiener integrals which are meant specifically the conditional expectation E$^{w}$ (Z vertical bar X) of a real or complex valued Wiener integrable functional Z conditioned by the Wiener measurable functional X on the Wiener measure space (A precise definition of the conditional Wiener integral and a brief discussion of the Wiener measure space are given in Section 2). In [3] and [4] he derived some inversion formulae for conditional Wiener integrals and evaluated some conditional Wiener integrals E$^{w}$ (Z vertical bar X) conditioned by X(x)=x(t) for a fixed t>0 and x in Wiener space. Thus E$^{w}$ (Z vertical bar X) is a real or complex valued function on R$^{1}$. In this paper we shall be concerned with the random vector X given by X(x) = (x(s$_{1}$),..,x(s$_{n}$ )) for every x in Wiener space where 0=s$_{0}$ $_{1}$<..$_{n}$ =t. In Section 3 we will evaluate some conditional Wiener integrals E$^{w}$ (Z vertical bar X) which are real or complex valued functions on the n-dimensional Euclidean space R$^{n}$ . Thus we extend Yeh's results [4] for the random variable X given by X(x)=x(t) to the random vector X given by X(x)=(x(s$_{1}$).., x(s$_{n}$ )).

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수열합성법으로 합성된 나노 SmxCe1-xO2-2/x 분말의 수계 분산 (Dispersion of SmxCe1-xO2-2/x Nanoparticles which is Synthesized by Hydrothermal Process in Aqueous System)

  • 배동식;김은정;한경섭
    • 한국재료학회지
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    • 제15권2호
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    • pp.112-114
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    • 2005
  • Dispersion stability of the $Sm_xCe_{1-x}O_{2-2/x}$ nanoparticles, which was produced by hydrothermal process, was studied in aqueous suspension using ESA (Eletrokinetic Sonic Amplitude). The average particle size of the synthesized $Sm_xCe_{1-x}O_{2-2/x}$ at nanoparticles was about $5{\pm}2nm$. The dispersion and rheological behavior of the $Sm_xCe_{1-x}O_{2-2/x}$ nanoparticles aqueous suspension was investigated using $NH_4OH\;and\;HNO_3$ as a disperse agent. The colloidal stability of aqueous suspensions with $Sm_xCe_{1-x}O_{2-2/x}$ nanoparticles at different pH values has been investigated by means of zeta potential, average particle size, and the distribution of synthesized $Sm_xCe_{1-x}O_{2-2/x}$ nanoparticles. The isoelectric point of the $Sm_xCe_{1-x}O_{2-2/x}$ nanoparticles was at pH around 11 and the value of zeta potential was at its maximum near pH 6.5.

$Ni_{1-x}Zn_{x}Fe_{2}O_{4}(0{\leq}x{\leq}1)$ Ferrrite의 자기적 성질 연구 (A Study on Magnetic Properties of $Ni_{1-x}Zn_{x}Fe_{2}O_{4}(0{\leq}x{\leq}1)$ Ferrrite)

  • 조익한;양재석;김응찬;강신규
    • 한국자기학회지
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    • 제6권6호
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    • pp.397-404
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    • 1996
  • 본 연구에서는 세라믹 소결 방법중의 하나인 건식법으로 $Ni_{1-x}Zn_{x}Fe_{2}O_{4}$을 제조하고 상온에서의 X-선 회절과 $M\"{o}ssbauer$ 스펙트럼을 조사하였다. 시료들은 Zn 함유량 x가 증가됨에 따라 격자상수는 선형으로 증가하며 $8.3111{$\AA$}~8.4184{$\AA$}({\pm}0.0003)$이다. 산소 파라미터는 0.3799~0.3852이며, X가 증가됨에 따라 증가하며, 특히 x=0.4 ~ 0.8 사이에서 크게 증가하였다. $M\"{o}ssbauer$ 스펙트럼은 x가 0.6이하인 시료들은 초미세 자기장에 의한 고명흡수선을 나타내고, Zn 함유량 x가 증가됨에 따라 초미세 자기장은 감소하고 있다. 특히 x가 0.2에서 0.6인 스팩트럼은 Yafet-Kittel의 자기구조를 갖으며 x가 0.6인 시료는 완화현상에 의한 공명흡수선을 나타내고 있다. x가 0.8이상인 시료는 사중극자 분열에 의한 공명흡수선을 나타내고 있다. 또한 $M\"{o}ssbauer$ 스펙트럼으로 부터 이성질체 이동(IS), 사중극자 분열(QS), 초미세 자기장(HF), 자기 모우멘트(${\mu}_{B}$)의 Zn 함유량 x에 따른 변화를 조사하였다.

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아크릴 점착제의 최적물성에 관한 연구 (A Study on Optimization of Physical Properties of Acrylic Pressure Sensitive Adhesives)

  • 변상훈;김중현
    • 공업화학
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    • 제3권4호
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    • pp.678-685
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    • 1992
  • 기능성 단량체가 점착물성에 미치는 영향을 알아보기 위하여 아크릴산과 기타 단량체로 아크릴 수지를 라디칼 용액중합을 이용하여 4원공중합시킨 후 물성을 측정하였으며, 또한 최적 점착 물성을 얻기 위하여 통계적 분석 방법을 이용하여 검토하였다. 점착물성에 있어서 아크릴산이 아크릴아미드보다 점착력의 증가에 미치는 영향이 컸다. 반면에 tackiness의 감소에 있어서는 아크릴아미드의 영향이 아크릴산 보다 컸다. 통계적 방법을 인용하여 점착물성 중 점착력, tackiness 그리고 응집력을 최적화 시킨 결과 단량체의 성분 비율은 부틸 아크릴레이트 81.7 mole%, 아크릴산 8.0 mole%, 아크릴아미드 2.1 mole%, 비닐아세테이트 8.2 mole% 일 때로 나타났고 이 때의 추정 회귀식은 다음과 같았다. $D=.857+.072X_1-.114X_2-.027X_3-.126X_1{^2}-.046X_1{\cdot}X_2-.063X_1{\cdot}X_3-.152X_2{^2}+.027X2{\cdot}X_3-.120X_3{^2}$ $X_1$:coded acylic acid, $X_2$:coded acylamide, $X_3$:coded vinylacetate

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직물의 보온성에 관한 통계학적연구 (A Statistical Study on the Warmth Retaining Properties of Fabrics)

  • 이광배;이동표
    • 한국의류학회지
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    • 제9권1호
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    • pp.17-27
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    • 1985
  • In order to investigate the warmth retaining properties of fabrics some characteristics such as thickness. porosity, packing density, thermal conductivity, moisture regain and air permeability were measured and experimental results were analysed statistically to relate the warmth retaining properties with those characteristics. From the analysis, the following results were obtained. 1. When the warmth retaining properties of fabrics (Y) are dependent variable and thickness ($x_1$), porosity ($x_2$), packing density ($x_3$), thermal conductivity ($x_4$), moisture regain ($x_5$) and air permeability ($x_6$) are independent variables, the regression equation of warmth retaining properties can be represented as follows. 1) Y= 1.6005+46.817$x_1$, (R=0.9487) 2)Y=-1.4187+26.5072$x_1$+0.2055$x_2$(R=0.9704) 3) Y= -3.6908+17.4482$x_1$+0.1782$x_2$+28.3243$x_3$ (R=0.9756) 4) Y=0.9202+16.9553$x_1$+0. 1167$x_2$+30.3577$x_3$+1.8884$x_4$ (R=0.9792) 5) Y=0.9353+17.2266$x_1$+0.1177$x_2$+28.9821$x_3$-1.8302$x_4$+0.0151$x_5$ (R=0.9792) 6) Y=0.7583+17.2343$x_1$+0.1196$x_2$+28.8830$x_3$-1.8336$x_4$+0.0187$x_5$0.0004$x_5$ (R=0.9792) 2. The warmth retaining properties of fabrics are merely affected by adding thermal conductivity, moisture regain and multiple regression equation which contains thickness, porosity and packing density as variables. Therefore the multiple regression which contains thickness, porosity and packing density as variables Y=-3.6908+17.4482$x_1$+0.1782$x_2$+28.3243$x_3$ is highly practical.

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ON A CHARACTERIZATION OF THE EXPONENTIAL DISTRIBUTION BY CONDITIONAL EXPECTATIONS OF RECORD VALUES

  • Lee, Min-Young
    • 대한수학회논문집
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    • 제16권2호
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    • pp.287-290
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    • 2001
  • Let X$_1$, X$_2$, … be a sequence of independent and identically distributed random variables with continuous cumulative distribution function F(x). X(sub)j is an upper record value of this sequence if X(sub)j > max {X$_1$, X$_2$, …, X(sub)j-1}. We define u(n) = min {j│j > u(n-1), X(sub)j > X(sub)u(n-1), n $\geq$ 2} with u(1) = 1. Then F(x) = 1 - e(sup)-x/c, x > 0 if and only if E[X(sub)n(n+1) - X(sub)u(n)│X(sub)u(m) = y] = c or E[X(sub)u(n+2) - X(sub)u(n)│X(sub)u(m) = y] = 2c, n $\geq$ m+1.

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HEREDITARY PROPERTIES OF CERTAIN IDEALS OF COMPACT OPERATORS

  • Cho, Chong-Man;Lee, Eun-Joo
    • 대한수학회보
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    • 제41권3호
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    • pp.457-464
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    • 2004
  • Let X be a Banach space and Z a closed subspace of a Banach space Y. Denote by L(X, Y) the space of all bounded linear operators from X to Y and by K(X, Y) its subspace of compact linear operators. Using Hahn-Banach extension operators corresponding to ideal projections, we prove that if either $X^{**}$ or $Y^{*}$ has the Radon-Nikodym property and K(X, Y) is an M-ideal (resp. an HB-subspace) in L(X, Y), then K(X, Z) is also an M-ideal (resp. HB-subspace) in L(X, Z). If L(X, Y) has property SU instead of being an M-ideal in L(X, Y) in the above, then K(X, Z) also has property SU in L(X, Z). If X is a Banach space such that $X^{*}$ has the metric compact approximation property with adjoint operators, then M-ideal (resp. HB-subspace) property of K(X, Y) in L(X, Y) is inherited to K(X, Z) in L(X, Z).

FUNCTIONAL EQUATIONS IN THREE VARIABLES

  • Boo, Deok-Hoon;Park, Chun-Gil;Wee, Hee-Jung
    • 충청수학회지
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    • 제17권2호
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    • pp.169-190
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    • 2004
  • Let r, s be nonzero real numbers. Let X, Y be vector spaces. It is shown that if a mapping f : $X{\rightarrow}Y$ satisfies f(0) = 0, and $$sf(\frac{x+y{\pm}z}{r})+f(x)+f(y){\pm}f(z)=sf(\frac{x+y}{r})+sf(\frac{y{\pm}z}{r})+sf(\frac{x{\pm}z}{r})$$, or $$sf(\frac{x+y{\pm}y}{r})+f(x)+f(y){\pm}f(z)=f(x+y)+f(y{\pm}z)+f(x{\pm}z)$$ for all x, y, $z{\in}X$, then there exist an additive mapping A : $X{\rightarrow}Y$ and a quadratic mapping Q : $X{\rightarrow}Y$ such that f(x) = A(x) + Q(x) for all $x{\in}X$. Furthermore, we prove the Cauchy-Rassias stability of the functional equations as given above.

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Quasi-F 공간과 극소 Quasi-F cover의 역사적 배경 (Historical backgrounds of Quasi-F spaces and minimal quasi-F covers)

  • 김창일
    • 한국수학사학회지
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    • 제18권4호
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    • pp.113-124
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    • 2005
  • 티코노프공간 X에 대하여 C(X)와 $C^*(X)$는 Riesz-공간이다 C(X)가 순서-코시완비일 필요충분한조건은 X가 quasi-F 공간이고, X가 컴팩트공간이며 QF(X)가 X의 극소 quasi-F cover일 때, C(X)의 순서-코시완비화와 C(QF(X))는 동형이다. 본 논문에서는 quasi-F 공간의 정의와 극소 quasi-F cover의 구성에 관한 동기 및 역사적 배경을 살펴본다.

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