• Title/Summary/Keyword: direct sum

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A NOTE ON G-VECTOR BUNDLES

  • KIM, YANG-KON
    • Honam Mathematical Journal
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    • v.2 no.1
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    • pp.37-44
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    • 1980
  • 우리는 먼저 Principal G-bundle와 성질을 살피고 representation of G over C를 irreducible CG-space의 direct sum으로 표시하여 Schur's Lemma를 이용하면 E가 임의의 CG-space, ${\sigma}E=Hom_c(E{\sigma},E)$라 할 때 ${\oplus}_{\sigma}(E_{\sigma}{\otimes}{\sigma}E){\rightarrow}E$ 가 G-ismorphism이 됨을 알아본다. 본 논문의 목적은 이러한 결과를 이용하여 K(X)와 $K_G(X)$의 관계를 구명하는데 있다.

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THE GROUP OF UNITS OF SOME FINITE LOCAL RINGS I

  • Woo, Sung-Sik
    • Journal of the Korean Mathematical Society
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    • v.46 no.2
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    • pp.295-311
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    • 2009
  • The purpose of this paper is to identify the group of units of finite local rings of the types ${\mathbb{F}}_2[X]/(X^k)$ and ${\mathbb{Z}}_4[X]/I$, where I is an ideal. It turns out that they are 2-groups and we give explicit direct sum decomposition into cyclic subgroups of 2-power order and their generators.

On the Fitting ANOVA Models to Unbalanced Data

  • Jong-Tae Park;Jae-Heon Lee;Byung-Chun Kim
    • Communications for Statistical Applications and Methods
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    • v.2 no.1
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    • pp.48-54
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    • 1995
  • A direct method for fitting analysis-of-variance models to unbalanced data is presented. This method exploits sparsity and rank deficiency of the matrix and is based on Gram-Schmidt orthogonalization of a set of sparse columns of the model matrix. The computational algorithm of the sum of squares for testing estmable hyphotheses is given.

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DIRECT SUM FOR BASIC COHOMOLOGY OF CODIMENSION FOUR TAUT RIEMANNIAN FOLIATION

  • Zhou, Jiuru
    • Bulletin of the Korean Mathematical Society
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    • v.57 no.6
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    • pp.1501-1509
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    • 2020
  • We discuss the decomposition of degree two basic cohomology for codimension four taut Riemannian foliation according to the holonomy invariant transversal almost complex structure J, and show that J is C pure and full. In addition, we obtain an estimate of the dimension of basic J-anti-invariant subgroup. These are the foliated version for the corresponding results of T. Draghici et al. [3].

SOME ONE-DIMENSIONAL NOETHERIAN DOMAINS AND G-PROJECTIVE MODULES

  • Kui Hu;Hwankoo Kim;Dechuan Zhou
    • Bulletin of the Korean Mathematical Society
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    • v.60 no.6
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    • pp.1453-1461
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    • 2023
  • Let R be a one-dimensional Noetherian domain with quotient field K and T be the integral closure of R in K. In this note we prove that if the conductor ideal (R :K T) is a nonzero prime ideal, then every finitely generated reflexive (and hence finitely generated G-projective) R-module is isomorphic to a direct sum of some ideals.

Implementation and the Energy Efficiency of the Kinetic Shading System (가동형 차양 시스템의 구성과 에너지 효율)

  • Han, Seung-Hoon
    • KIEAE Journal
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    • v.14 no.5
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    • pp.67-73
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    • 2014
  • This study aims at examining kinetic efficient shading systems and their implementation methods. These days, the importance of the shading devices are getting more significant due to the energy problem. Cordially, suitable shade designs are required as an important element for the exterior envelope of the building. This study employs the optimal shading design as an efficient shading method with the kinetic system that can be converted actively by the altitude of the sun. The proposed kinetic shading system works not only as a lightshelf in case the altitude of the sun is high but also as a vertical louver when the sun is getting lower in order to block the direct sunlight. This study has analyzed the thermal performance and shading coefficient of the kinetic shading system in comparison to existing fixed shading devices using the Ecotect. The results, in sum, conclude that the suggested kinetic shading system could decrease direct sunlights 26.2% more than the existing shading methods.

A Joint Scheme of AGC and Gain/Phase Mismatch Compensation for QPSK DCR

  • Song, Yun-Jeong;Lee, Ho-Jin;Ra, Sung-Woong;Kim, Young-Wan
    • ETRI Journal
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    • v.26 no.5
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    • pp.501-504
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    • 2004
  • This paper presents a simple gain/phase blind compensation algorithm with an automatic gain control (AGC) function for the adoption of the AGC function and compensation for gain/phase imbalances in quadrature phase shift keying (QPSK) direct conversion receivers (DCRs). The AGC function is interactively operated with the compensation algorithm for gain/phase imbalances. By detecting the gain sum and difference values between the I-channel and Q-channel, the combined AGC and gain imbalance compensation algorithm provides a simpler DCR architecture.

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Baer and Quasi-Baer Modules over Some Classes of Rings

  • Haily, Abdelfattah;Rahnaou, Hamid
    • Kyungpook Mathematical Journal
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    • v.51 no.4
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    • pp.375-384
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    • 2011
  • We study Baer and quasi-Baer modules over some classes of rings. We also introduce a new class of modules called AI-modules, in which the kernel of every nonzero endomorphism is contained in a proper direct summand. The main results obtained here are: (1) A module is Baer iff it is an AI-module and has SSIP. (2) For a perfect ring R, the direct sum of Baer modules is Baer iff R is primary decomposable. (3) Every injective R-module is quasi-Baer iff R is a QI-ring.

Performance Prediction of a Solar Power System with Stirling Engine (Matching Collector/Receiver with Engine/Generator Systems) (스털링엔진 태양열 발전시스템의 성능예측(집열기.수열기 및 엔진.발전기 시스템의 조화))

  • Bae, Myung-Whan;Chang, Hyung-Sung
    • Proceedings of the KSME Conference
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    • 2001.11b
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    • pp.794-799
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    • 2001
  • The simulation analyses of a solar power system with monolithic concentrator by using a stirling engine are carried out to predict the system performance in four test sites. The site has different intensities and distributions of direct solar radiation respectively. Seoul, Pusan and Cheju in Korea, and Naha in Japan are selected as test sites. To accomplish the same demand of a 25 kW output that the power level of a system has, it needs to take the matching of collector/receiver with engine/generator systems. In such a case, also, the size of the collector is sometimes adjusted. In this study, the diameter of the collector is decided by using the solar radiation of design point, which is defined as the sum of average and standard deviation $\sigma$ of maximum direct solar radiation distribution for a day during a year in the respective test site. It is found that the average power output during the system operating time in the case of slope error ${\sigma}_s=2.5$ is within the range of 9 to 13 kW.

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Effect of C18-polyunsaturated Fatty Acids on Their Direct Incorporation into the Rumen Bacterial Lipids and CLA Production In vitro

  • Choi, S.H.;Song, M.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.4
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    • pp.512-515
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    • 2005
  • An in vitro study was conducted to determine the effect of C18-polyunsaturated fatty acid on direct incorporation into the rumen bacteria, bio-hydrogenation and production of CLA in vitro. Sixty milligrams of linoleic acid ($C_{18:2}$) or linolenic acid ($C_{18:3}$) were absorbed into the 0.5 g cellulose powder was added to the 150 ml culture solution consisting of 120 ml McDougall's buffer and 30 ml strained rumen fluid. Four uCi of 1-$^{14}C_{18:2}$ or 1-$^{14}C_{18:3}$ (1 uCi/15 mg each fatty acid) were also added to the corresponding fatty acids to estimate the direct incorporation into the bacterial lipids. The culture solution was then incubated anaerobically in a culture jar with stirrer at 39$^{\circ}C$ for 12 h. Ammonia concentration and pH of the culture solution were slightly influenced by the fatty acids. Amount of fatty acid incorporated into the bacteria was 1.20 mg and 0.43 mg/30 ml rumen fluid for $C_{18:2}$ and $C_{18:3}$, respectively during 12 h incubation. Slightly increased CLA (sum of cis-9, trans-11 and cis-10, trans-12 $C_{18:2}$) was obtained from the $C_{18:3}$ addition compared to that from $C_{18:2}$ after 12 h incubation in vitro.