• Journal of the Chungcheong Mathematical Society
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• v.15 no.1
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• pp.75-85
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• 2002

Let X be a compact metric space and let f be a continuous relation on X. Let U be an attractor block for f and let A bean attractor determined by U. Then there exists a continuous function ${\lambda}^{-1}:X{\rightarrow}[0,1]$ such that ${\lambda}^{-1}(0)=A$, ${\lambda}^{-1}(1)=X-B(A,U)$, and $M({\lambda},f)(x)$ < ${\lambda}(x)$ for all $x{\in}B(A,U)-A$.

• Communications of the Korean Mathematical Society
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• v.23 no.2
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• pp.201-209
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• 2008

In this paper we introduce two products of tempered distributions with positive support. These products are based in the Laguerre representation of distributions. We calculate some products as, $[{\delta}]x^{\lambda}_+={\delta}[x^{\lambda}_+]=0\;and\;[x^{\lambda}_+]x^{\mu}_+=x^{{\lambda}+{\mu}}_+$ for appropriate ${\lambda}$ and ${\mu}$.

• Communications for Statistical Applications and Methods
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• v.2 no.1
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• pp.55-63
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• 1995

The characteristics of $I{\lambda}$-optimality are investigated with repsect to other experimental design's criteria, D-and G-optimality. The comparisons are based on D- and G-, and $I{\lambda}$-efficiencies using the Beta(p, q) distribution as a weighting function for $I{\lambda}$-optimality. Results indicate that serious consideration should be given to the $I{\lambda}$-optimality criterion especially when the error variance function is not homogeneous.

• Journal of the Chungcheong Mathematical Society
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• v.4 no.1
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• pp.45-48
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• 1991

Wiener measure $m({\lambda}B)$ can behave arbitrarily badly as a function of ${\lambda}$ for Wiener measurable sets B. We show however that $m({\lambda}B)$ is Borel measurable with respect to ${\lambda}$ for any Borel subset B of $C_0$[0, 1].

• Proceedings of the Korean Statistical Society Conference
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• 2001.11a
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• pp.109-114
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• 2001

m=2 또는 n=2이고, ${\lambda}_1<{\lambda}_2$인 그룹분류가능계획을 매개디자인으로 사용한 완전이면교배가 A-최적, D-최적임을 보였다. 또한, ${\lambda}_2={\lambda}_1+1$이면 일반화된 최적계획이 됨을 보였다.

• Bulletin of the Korean Chemical Society
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• v.34 no.7
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• pp.2117-2124
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• 2013

The binding properties and sequence selectivities of ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ (bip = 4,4'-biphenylene (imidazo [4,4-f][1,10]phenanthroline) complexes with $poly[d(A-T)_2]$ and $poly[d(G-C)_2]$ were investigated using conventional spectroscopic methods. When bound to $poly[d(A-T)_2]$, a large positive circular dichroism (CD) spectrum was induced in absorption region of the bridging moiety for both the ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complexes, which suggested that the bridging moiety sits in the minor groove of the polynucleotide. As luminescence intensity increased, decay times became longer and complexes were well-protected from the negatively charged iodide quencher compared to that in the absence of $poly[d(A-T)_2]$. These luminescence measurements indicated that Ru(II) enantiomers were in a less polar environment compared to that in water and supported by minor groove binding. An angle of $45^{\circ}$ between the molecular plane of the bridging moiety of the ${\Delta}{\Delta}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complex and the local DNA helix axis calculated from reduced linear dichroism ($LD^r$) spectrum further supported the minor groove binding mode. In the case of ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complex, this angle was $55^{\circ}$, suggesting a tilt of DNA stem near the binding site and bridging moiety sit in the minor groove of the $poly[d(A-T)_2]$. In contrast, neither ${\Delta}{\Delta}$-nor ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complex produced significant CD or $LD^r$ signal in the absorption region of the bridging moiety. Luminescence measurements revealed that both the ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complexes were partially accessible to the $I^-$ quencher. Furthermore, decay times became shorter when bis-Ru(II) complexes bound to $poly[d(G-C)_2]$. These observations suggest that both the ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ complexes bind at the surface of $poly[d(G-C)_2]$, probably electrostatically to phosphate group. The results indicate that ${\Delta}{\Delta}$- and ${\Lambda}{\Lambda}-[{\mu}-Ru_2(phen)_4(bip)]^{4+}$ are able to discriminate between AT and GC base pairs.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.5 s.96
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• pp.465-471
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• 2005

A method of calculation fur propagating and focusing of focused beams generated in antenna arrays, using BPM(Beam Propagation Method), is presented in this paper. Based on the diffraction theory, the beam focusing and Propagation is studied specially for the case of the antenna way fed by the Rotman lens that is able to focus microwave power on its focal arc or generate multiple beams. There are difficulties in performing a full-wave simulation using a commercial EM simulation tool for propagating and focusing of beams because of the structural complexity and the feeding assignment of the antenna array. Therefore, as an alternative solution, the BPM is presented to calculate the beam propagation from the aperture-type antennas. From the point of view of optics, the propagations of the lens have been simplified from the Fresnel diffraction integral to the Fourier transform. Using Fourier Transform, a beam propagation method is developed to show improvement of the resolution by controlling the wavefront of wave Propagating from an aperture-type antenna array. The beam width(or spot size) and the intensity are calculated for a focused beam propagating from an array having $10\lambda$ of its size. For the beams with $20\lambda,\;30\lambda$, and $50\lambda$ of geometrical focal length, the half-power beam widths(or spot size) are about 1.1\lambda,\;1.3\lambda,\;and\;1.9\lambda$ respectively.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.44-52
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• 2017

In this paper, we propose a DFD (Digital Frequency Discriminator) design that has better frequency discrimination and a smaller size. Electronic warfare equipment can analyze different types of radar signal such as those based on Frequency, Pulse Width, Time Of Arrival, Pulse Amplitude, Angle Of Arrival and Modulation On Pulse. In order for electronic warfare equipment to analyze radar signals with a narrow pulse width (less than 100ns), they need to have a special receiver structure called IFM (Instantaneous Frequency Measurement). The DFD (Digital Frequency Discriminator) is usually used for the IFM. Because the existing DFDs are composed of separate circuit devices, they are bulky, heavy, and expensive. To remedy these shortcomings, we use a three delay line ($1{\lambda}$, $4{\lambda}$, $16{\lambda}$) in the DFD, instead of the four delay line ($1{\lambda}$, $4{\lambda}$, $16{\lambda}$, $64{\lambda}$) generally used in the existing DFDs, and apply the microwave integrated circuit method. To enhance the frequency discrimination, we detect the pulse amplitude and perform temperature correction. The proposed DFD has a frequency discrimination error of less than 1.5MHz, affording it better performance than imported DFDs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.12 no.1
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• pp.1-6
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• 1979

본연구에서는 그물어구의 상사를 지배하는 무차원수 K를 $$K=\frac{{\nu}^n\rho_wv^{2-n}}{{d^{1+n}(\rho-\rho_w)}$$ d, p: 재료의 직경 및 밀도 $\nu,\rho_w,v$: 물의 동점성계수, 밀도 및 속도으로 정하고, 여기에서의 직경의 비를 결정하는 방법에 따라 실물과 모형과의 상사를 완전하게 그리고 근사적으로 만족시키는 조건들을 구하였다. 즉, 원전한 상사한 경우는 직경의 비를 축척비와 같게 하고, 나아가서 다른 모든 치수의 비도 축척비와 같게 함으로써 만족된다고 하였으며, 측사적 상사의 경우느 직경의 비가 축척비 $(\frac{\lambda_2}{\lambda_1})$와 같지 않아도 된다고 하여, 그물실의 직경 d, 코의 크기 $\iota$ 및 콧수 N의 비를 $$\frac{d_2}{d_1}=\frac{\iota_2}{\iota_1}=\frac{\lambda_2}{\lambda_1}{\cdot}\frac{N_1}{N_2}$$ 으로, 줄의 직경 d', 길이 $\iota'$ 및 밀도 $\rho'$의 비를 $$\frac{d_2'}{d_1'}=\sqrt{{\frac{\lambda_2}{\lambda_1}}\cdot{\frac{d_2}{d_1}}\cdot{\frac{\rho_2-\rho_{w2}}{\rho_1-\rho_{w1}}\cdot{\frac{\rho_1'-\rho_{w1}}{\rho_2'-\rho_{w2}}}}$$, $\frac{\iota_2'}{\iota_1'}=\frac{\lambda_2}{\lambda_1}$로, 부속구의 치경 $d'$, 밀도 $\rho'$ 및 수 $N'$의 비를 $$\frac{N_2'}{N_1'}=(\frac{\lambda_2}{\lambda_1})^2(\frac{d_2}{d_1})(\frac{d_1'}{d_2'})\frac{(\rho_2-\rho_{w2})}{(\rho_1-\rho_{w1})}\frac{(\rho_1'-\rho_{w1})}{(\rho_2'-\rho_{w2})}$$으로 정하였다. 이렇게 정해진 모형어구에 대해 유속 v의 비느 $K_1=K_2$로부터 $$(\frac{u_2}{u_1})^{2-n}=(\frac{\nu_2}{\nu_1})^{-n}\;(\frac{\rho_{w1}}{\rho_{w2}})\;(\frac{\rho_2-\rho_{w2}}{\rho_1-\rho_{w1}})\;(\frac{d_2}{d_1})^{1+n}$$으로 주어지므로, 이를 이용하여 어구저항 D 및 그물감의 다리에서의 장력 $\tau$의 비를 $$\frac{D_2}{D_1}=\frac{d_2(\rho_2-\rho_{w2})}{d_1(\rho_1-\rho_{w1})}(\frac{\lambda_2}{\lambda_1})^2$$ $${\frac{\tau_2}{\tau_1}=\frac{d_2\iota_2(\rho_2-\rho_{w2})}{d_1\iota_1(\rho_1-\rho_{w1})}\;{\cdot}\frac{\lambda_2}{\lambda_1}$$로 정하였다.

• Communications of the Korean Mathematical Society
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• v.22 no.1
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• pp.41-51
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• 2007

Let R be a ring with left identity e and suitably-restricted additive torsion, and Z(R) its center. Let H : $R{\times}R{\times}R{\rightarrow}R$ be a symmetric 3-additive mapping, and let h be the trace of H. In this paper we show that (i) if for each $x{\in}R$, $$n=<<\cdots,\;x>,\;\cdots,x>{\in}Z(R)$$ with $n\geq1$ fixed, then h is commuting on R. Moreover, h is of the form $$h(x)=\lambda_0x^3+\lambda_1(x)x^2+\lambda_2(x)x+\lambda_3(x)\;for\;all\;x{\in}R$$, where $\lambda_0\;{\in}\;Z(R)$, $\lambda_1\;:\;R{\rightarrow}R$ is an additive commuting mapping, $\lambda_2\;:\;R{\rightarrow}R$ is the commuting trace of a bi-additive mapping and the mapping $\lambda_3\;:\;R{\rightarrow}Z(R)$ is the trace of a symmetric 3-additive mapping; (ii) for each $x{\in}R$, either $n=0\;or\;<n,\;x^m>=0$ with $n\geq0,\;m\geq1$ fixed, then h = 0 on R, where denotes the product yx+xy and Z(R) is the center of R. We also present the conditions which implies commutativity in rings with identity as motivated by the above result.