• Bulletin of the Korean Mathematical Society
• /
• v.51 no.6
• /
• pp.1605-1614
• /
• 2014

In continuation to the investigation initiated by Ferraz, Goodaire and Milies in [4], we provide an explicit description for the Wedderburn decomposition of finite semisimple group algebras of the class of finite groups G, such that $$G/Z(G){\simeq_-}C_2{\times}C_2$$, where Z(G) denotes the center of G.

• Journal of the Korean Operations Research and Management Science Society
• /
• v.14 no.2
• /
• pp.19-26
• /
• 1989

We in this paper have defined the concept of .epsilon.-symmetric relation between the Lagrangean relaxation and the Benders' decomposition. This links the solutions of the Lagrangean subproblems and those of the Benders' subproblems even under positive duality gaps. As an application we have discussed the reduction of the size for a special class of problems.

• Korean Journal of Mathematics
• /
• v.32 no.1
• /
• pp.163-171
• /
• 2024

In this paper, we proceeded to the classification of four dimensional baric algebras strictly satisfying a polynomial identity of degree six. After some results on the structure of such algebras, we show that the type of an algebra of the studied class is an invariant under change of idempotent in the Peirce decomposition. This last result plays a major role in our classification.

• Kyungpook Mathematical Journal
• /
• v.64 no.2
• /
• pp.245-260
• /
• 2024

In this study, we establish some new characterizations for a class of anisotropic Herz spaces in which all exponents are considered as variables. We also provide a description of these spaces based on bloc decomposition. As an application, we investigate the boundedness of certain sublinear operators within these function spaces.

• Geophysics and Geophysical Exploration
• /
• v.15 no.1
• /
• pp.39-46
• /
• 2012

Recently, stratigraphic reservoirs are getting more attention than structural reservoirs which have mostly developed. However, recognizing stratigraphic thin gas reservoirs in a stacked section is usually difficult because of tuning effects. Moreover, if the reflections from the brine-saturated region of a thin layer have the same polarity with those from the gas-saturated region, we could not easily identify the gas reservoir with conventional data processing technique. In this study, we introduced a way to delineate the gas-saturated region in a thin layer reservoir using a spectral decomposition method. First of all, amplitude spectrum with the variation of the frequency and the incident angle was investigated for the medium which represents property of Class 3, Class 1 or Class 4 AVO response. The results show that the maximum difference in the amplitude spectra between brine and gas-saturated thin layers occurs around the peak frequency independent of the incident angle and the type of AVO responses. In addition, the amplitude spectra of the gas-saturated zone are greater than those of brine-saturated one in Class 3 and Class 4 at the peak frequency while those of phenomenon occur oppositely in Class 1. Based on the results, we applied spectral decomposition method to the stacked section in order to distinguish the gas-saturated zone from the brine-saturated zone in a thin layer reservoir. To verify our new method, we constructed a thin-layer velocity model which contains both gas and brine-saturated zones which have the same reflection polarities. As a result, in the spectral decomposed sections near the peak frequency obtained by Wigner-Ville Distribution (WVD), we could identify the difference between reflections from gas- and brinesaturated region in the thin layer reservoir, which was hardly distinguishable in the stacked section.

• Journal of Industrial Technology
• /
• v.28 no.B
• /
• pp.143-148
• /
• 2008

A real-time face detection is to find human faces robustly under the cluttered background free from the effect of occlusion by other objects or various lightening conditions. We propose a face detection system for real-time applications using wavelet decomposition method based on Gabor features. Firstly, skin candidate regions are extracted from the given image by skin color filtering and projection method. Then Gabor-feature based template matching is performed to choose face cadidate from the skin candidate regions. The chosen face candidate region is transformed into 2-level wavelet decomposition images, from which feature vectors are extracted for classification. Based on the extracted feature vectors, the face candidate region is finally classified into either face or nonface class by the Levenberg-Marguardt back-propagation neural network.

• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2012.07a
• /
• pp.176-177
• /
• 2012

사람의 음성을 압축하는 방법으로 Code Excited Linear Prediction (CELP) 코더가 주로 사용되어 왔다. CELP 코더의 수신단에서는 양자화 된 여기신호를 LPC 필터로 합성하여 신호를 복원한다. LPC 합성필터의 영향으로 양자화 된 여기신호의 보로노이 셀 모양이 변형되는 문제점이 있기 때문에 이런 문제점을 해결하기 위해서 Karhunen-Loeve-Transform based Classify vector Quantization (KLT-CVQ) 코더가 제안되었다. 기존 KLT-CVQ 코더는 KLT 변환과 class 선택을 위해서 Eigen Value Decomposition (EVD)을 이용해서 eigen vector와 eigen value를 계산한다. 본 논문에서는 EVD 대신에 UTV Decomposition (UTVD)을 이용하여 KLT-CVQ의 계산량 문제점을 개선하는 방법을 제안한다.

• Journal of Electrical Engineering and information Science
• /
• v.2 no.5
• /
• pp.121-128
• /
• 1997

This paper proposes a class of rearrangeable networks, called generalized rearrangeable networks(GRNs). GRNs are obtained from the Benes network by rearranging the connections between states and the switches within each stage. The GRNs constitute all of the rearrangeable networks which have the recursive decomposition structure and can be routed by the outside-in decomposition of permutations as the Bene network. This paper also presents a necessary condition for a network to be a GRN and a network labeling scheme to check if a network satisfies the condition. the general routing algorithm for the GRNs is given by modifying slightly the looping algorithm of the Benes network.

• Journal of the Korea Computer Industry Society
• /
• v.2 no.9
• /
• pp.1199-1208
• /
• 2001

Program slicing is a program decomposition technique to improve the effectiveness of program testing and maintenance. In this paper I propose a method for slicing object-oriented programs and show its correctness. Also, I propose the class interface slicing technique which can eliminate irrelevant data members, subobjects, and methods from the class declaration parts of the given program. And I show its correctness. Finally, I propose the class hierarchy slicing technique which can compute the declarative parts affecting or affected by the given data member. These techniques may be used for information analysis in some area such as class testing.

• The Korean Journal of Soil Zoology
• /
• v.2 no.2
• /
• pp.83-91
• /
• 1997

One year study with litter bags(mesh size - 0.4mm, 0.8mm, 1.7mm and 5.0mm) was carried out to investigate the soil invertebrate community in the process of leaf decomposition in Namsan and Kwangreung deciduous forests, which were considered to be under different degrees of environmental selective pressure. Soil animals collected from litter bags were classified into the class of order or higher taxa. Acari and Collembola were major groups: Acari and Collembola were about 60% and 30% of total soil animals in their numbers, respectively. Among minor groups, Dipteria, Araneae, Diplopoda, Coleoptera and Chilopoda were comparatively dominant. In Namsan forest which was considered to be under higher environmental selective pressure than Kwangreung, the densities of Acari and Collembola were somewhat higher than in Kwangreung, although there was no statistically significant difference between two sites. The densities of Chilopoda, Enchytraeidae and Nematoda were much higher in Namsan than in Kwangreung but Diplopoda and Symphyla were much more in Kwangreung. It was expected that those groups could be used as bioindicators. The densities of Acari and Collembola were very low until March and then showed the peak in May. But they decreased slowly until November. There was no significant difference among the mesh sized of litter bags in the densities of Acari and Collembola but other groups of soil invertebrates seemed to be prevented from immigrating into the litter bag of mesh size 0.4mm. Decomposition rate of litter in the litter bag was low in early stage of decomposition. The % residual mass over initial mass at 8 months after litter bag introduction in the field was over 80%. Thereafter, % residual mass decreased more fast and was about 60% at 1 year after bag introduction. There was little evidence for the effects of soil invertebrates upon the litter decomposition in the period of this study. And there was no significant difference between Namsan and Kwangreung or among mesh sizes of litter bags in the decomposition rate.