• Communications for Statistical Applications and Methods
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• v.11 no.1
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• pp.161-168
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• 2004

A single-index model is useful in fields which employ multidimensional regression models. Many methods have been developed in parametric and nonparametric approaches. In this paper, posterior inference is considered and a wavelet series is thought of as a function approximated to a true function in the single-index model. The posterior inference needs a prior distribution for each parameter estimated. A prior distribution of each coefficient of the wavelet series is proposed as a hierarchical distribution. A direction $\beta$ is assumed with a unit vector and affects estimate of the true function. Because of the constraint of the direction, a transformation, a spherical polar coordinate $\theta$, of the direction is required. Since the posterior distribution of the direction is unknown, we apply a Metropolis-Hastings algorithm to generate random samples of the direction. Through a Monte Carlo simulation we investigate estimates of the true function and the direction.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.25 no.8
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• pp.1110-1116
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• 2021

In this paper, we propose a conformal Ku-band data link antenna to ensure low RCS of stealth UAV. As a phased array antenna with electrical beam steering function, a transmitter and a receiver were designed and manufactured for FDD communication, respectively. Each antenna is designed as a 12*12 planar array antenna and has a function to form a uni-directional pattern and a bi-directional pattern through phase control of unit elements. The beam steering range is designed to be able to steer up to 60 degrees in theta direction and 360 degrees in the phi direction. As a result of manufacturing and measurement, the conformal type radome has low transmission loss and meets the required specifications including system performance. The feasibility of mounting the stealth UAV has been confirmed, and future research directions such as interworking of baseband devices and conversion to digital beam steering function are suggested.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.462-470
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• 2015

This study examined for which socio-economic difference effects on brain function and Problem behavior syndrome in children. About a children with no disorders, diseases or cognitive dysfunction-30 were from LIC children and another 30, from MC ones, the study was conducted by measuring and analyzing the data using brain function analysis and K-CBCL from January to April, 2013. The results of the study are as follows. First, it was found that the ratio of LIC's theta(${\Theta}$) and SMR waves and that of delta(${\delta}$), high beta(${\beta}h$), alpha(${\alpha}$) and low beta(${\beta}l$) waves showed significantly higher values than MC children. Second, concerning the symptoms of child behavioral problems, LIC showed significantly higher values than MC children in symptoms of the body, depression and anxiety, social immaturity, thinking problems, attention problems, aggression, internalization, externalization, overall behavioral problems, and emotional instability. MC children showed significantly higher values than LIC chidren in symptoms of social, academic-performance, total social skills. In conclusion, the significant difference of the brain functions and the symptoms of child behavioral problems between LIC and MC children showed that the socio-ecnomic difference has an influence on the same functions and symptoms above.

• Transactions of the Korean Society of Mechanical Engineers
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• v.15 no.2
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• pp.396-403
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• 1991

A solution is presented for the computation of the elastic-creep stresses in a hollow cylinder subjected to nonaxisymmetric temperature distribution. The creep problem is treated by the Maxwell creep model. Laplace transformation is used for reformation of the governing equation of elastic problem and Hooke's law in a function of .gamma. , .theta. , and creep constant. The governing equation is set up using the Airy stress function which leads to the biharmonic equation. The solution is obtained by using Fourer series method and Laplace inverse method used to obtain the stress components which include the variation of time. This solution shows excellent agreement with Lamkin's and Boley & Weiner's solution. The viscoelastic stresses are also obtained for the fuel rob tube subjecting nonaxisymmetric thermal load.

• Journal of Mechanical Science and Technology
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• v.17 no.12
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• pp.2034-2041
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• 2003

This study introduced a lattice Boltzmann computational scheme capable of modeling thermo hydrodynamic flows with simpler equilibrium particle distribution function compared with other models. The equilibrium particle distribution function is the local Maxwelian equilibrium function in this model, with all the constants uniquely determined. The characteristics of the proposed model is verified by calculation of the sound speeds, and the shock tube problem. In the lattice Boltzmann method, a thermal fluid or compressible fluid model simulates the reflection of a weak shock wave colliding with a sharp wedge having various angles $\theta$$\sub$w/. Theoretical results using LBM are satisfactory compared with the experimental result or the TVD.

• Journal of the Korean Chemical Society
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• v.16 no.5
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• pp.261-264
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• 1972

The cubic force constants of the binary hydrides, LiH, BeH, BH, CH, NH and OH are evaluated by use of the one center function of Bishop et. al. The results are reasonably good. The master formula suggested in the previous report of the present author is found relatively insensitive to the crudities of the wave function.

• Journal of the Korean Chemical Society
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• v.16 no.4
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• pp.214-218
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• 1972

The quadratic force constants of heteronuclear diatomic molecules, LiH, BeH, BH, CH, NH and OH are evaluated by use of the one center function of Bishop et. al. The master formula on which the computation is based was suggested by the previous work of one of the present authors. The results are in good agreement with the experimental values. It is found that around the nucleus of the atom located in the close vicinity of the expansion center of the one center function, the electronic distribution is relatively unrealistic, and the suggested formula would lead an erroneous result when one takes the origin of variables of $P_2(cos{\theta})/r_3$ at the atomic nucleus.

• Journal of the Korean Chemical Society
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• v.8 no.1
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• pp.30-32
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• 1964

H. Eyring등의 액체의 구조에 관한 이론에 따라서 액체 사염화탄소의 partition function을 정하였다. 이 Partition function 에 쓰인 parameter $E_s,\;{\sigma},\;{\theta},\;V_s$ 등은 액체 안의 고체와 같은 분자의 고요한 값으로 새로운 방법$^{(4)}$으로 그 값들을 정하였다. 이렇게 정해진 Partition function을 써서 액체 사염화탄소의 몰부피, 증기압, 한계점, 증발엔트로피 및 표면장력 등을 계산하였다. 계산치와 실측치를 비교한 결과 몰부피와 증기압, 엔트로피의 값은 거의 일치하였다. 표면장력 또한 실험치와 좋은 일치를 보여주는 값을 얻었다.

• Journal of the Korean Chemical Society
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• v.8 no.2
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• pp.65-67
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• 1964

The partition function of liquid fluorine were developed by applying the theory of significant structures in liquids. The molar volume, vapor pressure, entropy of vaporization and surface tension of the liquid were calculated over a wide temperature range. The critical properties for the liquid were also calculated. The results show good agreement with experimental observations.

• Journal of the Korean Magnetics Society
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• v.10 no.3
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• pp.99-105
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• 2000

One dimensional magneto-photonic crystal having structure of (A/B)$^{k/W}$(B/A)$^{k}$ , where M is a magnetic layer of highly Bi-substituted iron garnet, A and B are dielectric layers of $SiO_2$ and T $a_2$O$_{5/}$, and k is the stacking number of the dielectric layers, has been numerically analyzed as a function of the thickness (d$_{M}$) of M (1∼535 nm) and the stacking numer of k (5∼15). The transmittance, Faraday rotation, and figure of merit of the magneto-photonic crystal have been investigated both in the visible and infrared wavelengths. A factor of several and several tens greater Faraday rotation and figure of merit have been obtained compared to the single layer of M, at many localized modes. In the visible the maximum figure of merit of 0.15 was obtained ( = 720 nm) when k = 11 and d$_{M}$ = 375 nm with T : 0.54, $\theta$$_{F}$ = 8.13$^{\circ}$, which was a factor of 30 greater than that of single garnet layer. Much greater maximum figure of merit, 0.285, was obtained in the infrared ( = 1114 nm) when k = 11 and d$_{M}$ = 800 nm with T = 0.66, $\theta$$_{F}$ = 18$^{\circ}$, which was a factor of 100 greater than that of single garnet layer.