• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권4호
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• pp.1638-1654
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• 2018

The heterogeneous network (HetNet) has been one of the key technologies in Long Term Evolution-Advanced (LTE-A) with growing capacity and coverage demands. However, the introduction of femtocells has brought serious co-layer interference and cross-layer interference, which has been a major factor affecting system throughput. It is generally acknowledged that the resource allocation has significant impact on suppressing interference and improving the system performance. In this paper, we propose a hybrid-clustering algorithm based on the $Mat{\acute{e}}rn$ hard-core process (MHP) to restrain two kinds of co-channel interference in the HetNet. As the impracticality of the hexagonal grid model and the homogeneous Poisson point process model whose points distribute completely randomly to establish the system model. The HetNet model based on the MHP is adopted to satisfy the negative correlation distribution of base stations in this paper. Base on the system model, the spectrum sharing problem with restricted spectrum resources is further analyzed. On the basis of location information and the interference relation of base stations, a hybrid clustering method, which takes into accounts the fairness of two types of base stations is firstly proposed. Then, auction mechanism is discussed to achieve the spectrum sharing inside each cluster, avoiding the spectrum resource waste. Through combining the clustering theory and auction mechanism, the proposed novel algorithm can be applied to restrain the cross-layer interference and co-layer interference of HetNet, which has a high density of base stations. Simulation results show that spectral efficiency and system throughput increase to a certain degree.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 추계학술대회
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• pp.255-259
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• 1997

The essence of meridian collateral and acupoints is an overall physiologic unction with the level of multiple unctional states. However it is a pity that until present, so in this paper described about some experimental results of physical reactions of meridian and acupoints. In order to verify meridian pathway and channel theory of energy in body. It is suppose that substance of meridian is pathway channel of the meridian materials. In basic examination, It was analyzed spectrum of reflection waves after beat or continuos vibrate to meridian point and non-meridian point meridian line and non-meridian line. The characteristics of reflection waves similar to flow channel in hydrodynamic. So it be able to suggest that the meridian is pathway and channel in body.

• 대한수의학회지
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• 제26권2호
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• pp.225-228
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• 1986

Progesterone immunogen has been synthesized and its melting point, Rf-value, UV and IR spectrum have been measured to develope the essential step in antisera production against low molecular weight substance. Mixed anhydride reaction was used to conjugate $11{\alpha}$-hydroxy-progesterone with succinic anhydride. Melting point of one intermediate compound was $156^{\circ}C$, and Rf-value was 0.41 in benzene : acetone : methanol (5 : 5 : 2). Maximum absorbance was measured at 242nm and ${\varepsilon}$ was $1.641{\times}10^4cm^2/mole$. Loss of hydroxy group was observed at 3450nm, and carbonyl group was appeared at 1160nm, 1250nm and 2960nm. These results indicated that the intermediate compound was progesterone hemisuccinate. Maximum absorbance of progesterone bovine-serum albumin(BSA) conjugate was observed at 250nm. Molar ratio of progesterone to BSA was average 15.4 on UV spectrum.

• 한국지반공학회논문집
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• 제36권6호
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• pp.17-34
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• 2020

일반적으로 잔교식 구조물의 내진설계를 위한 응답스펙트럼 해석 시 기준서들에서는 지진응답해석을 통해 증폭된 가속도를 입력가속도 활용하도록 제시하고 있으나, 기준서에 따라 방법이 상이하여 설계 시 혼란을 야기할 수 있다. 이에, 본 연구에서는 동적원심모형실험을 통해 지반 내 다양한 깊이에서 지반 가속도를 산정하였으며, 산정된 지반가 속도를 활용하여 응답스펙트럼 해석을 수행하였다. 이후 실험 및 해석을 통해 도출된 잔교식 안벽 구조물의 모멘트 결과를 비교하였으며, 응답스펙트럼 해석 시 적절한 입력지반가속도를 결정하기 위한 방법을 제시하고자 하였다. 실험 및 해석을 비교한 결과, 탄성 지반 스프링을 적용하는 경우 구조물의 고유주기를 가장 적절하게 모사하는 것으로 나타났으며, 상부 지표면에서 증폭된 지진파를 입력가속도로 활용하는 것이 사질토 지반에 관입된 구조물 응답을 가장 합리적으로 모사하는 것으로 나타났다.

• 한국통신학회논문지
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• 제21권7호
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• pp.1668-1676
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• 1996

This paper presents the evaluation of an angular spectrum-based method used to calculate scattering pattern of a three-dimensional object modelled as a collection composed of vertical sectional two-dimensional images. This is done via comparing a proposed method with two existing methods, i.e., a Fresnel hologram method and a ray-tracing method, in terms of computatioal complexities and reconstructed results. Maathematical derivations for each methods are reviewed and implementing procedures are described in detail, along with the amount of computaions required from the implementation point of view, rather than from the mathematical point of view. We show simulation results in which the Fresnel holoram method dose not exhibit promising results although it requires the least computation. Moreover, it is also shown that the proposed method, even with much less computational requirement than the ray-tracing method, produces good performances asmuch as the ray-tracing method does.

• Korean Journal of Mathematics
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• 제28권3호
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• pp.439-447
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• 2020

Let M be a lattice module over a C-lattice L. Let Spec^s(M) be the collection of all second elements of M. In this paper, we consider a topology on Spec^s(M), called the second classical Zariski topology as a generalization of concepts in modules and investigate the interplay between the algebraic properties of a lattice module M and the topological properties of Spec^s(M). We investigate this topological space from the point of view of spectral spaces. We show that Spec^s(M) is always T₀-space and each finite irreducible closed subset of Spec^s(M) has a generic point.

• 한국전자파학회논문지
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• 제26권9호
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• pp.821-827
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• 2015

태양 흑점 폭발로 인해 방출되는 전자파는 지구상 낮 지역의 전파 통신에 장애를 일으킨다. 전세계에서 사용하는 태양 흑점 폭발 경보의 등급은 Geostationary Operational Environmental Satellite의 X선 세기에 따라 분류되고, 통신 장애를 판단한다. 하지만 태양과 직하점이 지구 자전에 따라 변하기 때문에 동일한 경보라도 통신 장애 영향은 같지 않다. 이러한 문제를 해결하기 위해 단파 통신을 전파 스펙트럼으로 수신하고, 통신 두절 여부를 모니터링하는 시스템을 개발하였다. 이 시스템은 단파 스펙트럼을 실시간 측정한 후 매분마다 자동으로 신호대 잡음비를 산출하고, ITU 권고의 간섭기준에 비교하여 통신 두절 시간을 산출한다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 추계학술대회논문집 II
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• pp.1089-1092
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• 2001

In order to measure the vibration of a ribbed clindrical shell, the principle of reciprocity has been implemented. An accelerometer was fixed at the position defined as the excitation point. An impact hammer was used to tap at the response array points (64 points) located along the circumference of the shell. The frequency response function was reciprocally measured at each point in turn. The response data was processed to obtain the frequency/wavenumber spectrum. From the spectrum the characteristics of wave propagation on the ribbed cylindrical shell have been observed.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1041-1041
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• 2001

Removal of variability in spectra data before the application of chemometric modeling will generally result in simpler (and presumably more robust) models. Particularly for sparsely sampled data, such as typically encountered in diode array instruments, the use of Savitzky-Golay (S-G) derivatives offers an effective method to remove effects of shifting baselines and sloping or curving apparent baselines often observed with scattering samples. The application of these convolution functions is equivalent to fitting a selected polynomial to a number of points in the spectrum, usually 5 to 25 points. The value of the polynomial evaluated at its mid-point, or its derivative, is taken as the (smoothed) spectrum or its derivative at the mid-point of the wavelength window. The process is continued for successive windows along the spectrum. The original paper, published in 1964 [1] presented these convolution functions as integers to be used as multipliers for the spectral values at equal intervals in the window, with a normalization integer to divide the sum of the products, to determine the result for each point. Steinier et al. [2] published corrections to errors in the original presentation [1], and a vector formulation for obtaining the coefficients. The actual selection of the degree of polynomial and number of points in the window determines whether closely situated bands and shoulders are resolved in the derivatives. Furthermore, the actual noise reduction in the derivatives may be estimated from the square root of the sums of the coefficients, divided by the NORM value. A simple technique to evaluate the actual convolution factors employed in the calculation by the software will be presented. It has been found that some software packages do not properly account for the sampling interval of the spectral data (Equation Ⅶ in [1]). While this is not a problem in the construction and implementation of chemometric models, it may be noticed in comparing models at differing spectral resolutions. Also, the effects on parameters of PLS models of choosing various polynomials and numbers of points in the window will be presented.

• 한국전산구조공학회논문집
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• 제15권1호
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• pp.21-32
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• 2002

일반적으로 응답스펙트럼 해석법은 건물의 지진해석에 널리 사용되고 있지만 기계하중이나 이동하중 등에 의하여 발생하는 진동에 대한 해석에는 시간이력해석이 주로 사용되고 있다. 그런데, 시간이력해석법은 정확한 반면 매우 복잡하고 어려우며 많은 시간을 필요로 한다. 따라서, 본 논문에서는 동적하중을 받는 구조물의 최대응답을 응답스펙트럼해석법을 이용하여 간편하게 계산하는 방법을 제시하고자 한다. 우선, 이 해석법의 해석과정에 대하여 알아보았으며, 복수절점에 동적 하중을 받는 경우에 대해서 해석시간 및 메모리를 줄이는 방법을 제시하였다. 다음으로는 이동하중을 받는 경우에 대하여 구조물의 최대응답을 구하는 방법에 대하여 알아보았다. 마지막으로 예제를 통하여 시간이력해석을 수행하여 얻은 최대응답과 응답스펙트럼해석에 의한 최대응답을 비교하여 제시한 해석법의 정확성을 확인하였다.