• Title/Summary/Keyword: cyclic-parallel

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CERTAIN RESULTS ON THREE-DIMENSIONAL f-KENMOTSU MANIFOLDS WITH CONFORMAL RICCI SOLITONS

  • Mandal, Tarak
    • Korean Journal of Mathematics
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    • v.30 no.1
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    • pp.1-10
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    • 2022
  • In the present paper, we have studied conformal Ricci solitons on f-Kenmotsu manifolds of dimension three. Also we have studied 𝜙-Ricci symmetry, 𝜂-parallel Ricci tensor, cyclic parallel Ricci tensor and second order parallel tensor in f-Kenmotsu manifolds of dimension three admitting conformal Ricci solitons. Finally, we give an example.

Direct Methods for Linear System on Distributed Memory Parallel Computers

  • Nishimura, S.;Shigehara, T.;Mizoguchi, H.;Mishima, T.;Kobayashi, H.
    • Proceedings of the IEEK Conference
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    • 2000.07a
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    • pp.333-336
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    • 2000
  • We discuss the direct methods (Gauss-Jordan and Gaussian eliminations) to solve linear systems on distributed memory parallel computers. It will be shown that the so-called row-cyclic storage gives rise to the best performance among the standard three (row-cyclic, column-cyclic and cyclic-cyclic) data storages. We also show that Gauss-Jordan elimination, rather than Gaussian elimination, is highly efficient for the direct solution of linear systems in parallel processing, though Gauss-Jordan elimination requires a larger number of arithmetic operations than Gaussian elimination. Numerical experiment is performed on HITACHI SR12201 with the standard libraries MPI and BLAS.

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A NOTE ON REAL HYPERSURFACES OF A COMPLEX SPACE FORM

  • Ki, U-Hang;Kim, He-Jin
    • Bulletin of the Korean Mathematical Society
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    • v.26 no.1
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    • pp.69-74
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    • 1989
  • Recently one of the present authors [2] asserted that a real hypersurface of a complex space form M$^{n}$ (c), c.neq.0, is of cyclic parallel if and only if AJ=JA and he showed also a complete and connected cyclic-parallel real hypersurface of M$^{n}$ (c), is congruent to type $A_{1}$, $A_{2}$ or A according as c>0 or c<0. A real hypersurface of a complex space form M$^{n}$ (c) is said to be covariantly cyclic constant if the cyclic sum of covariant derivative of the second fundamental form is constant. The purpose of the present paper is to extend theorem 3 and 4 in [2] when the hypersurfaces are of coveriantly cyclic constant, that is a real hypersurface of a complex space form M$^{n}$ (c), c.neq.0, is of covariantly cyclic constant if an only if AJ=JA, and a complete and connected covariantly cyclic constant real hypersurface of M$^{n}$ (c) is congruent to type $A_{1}$, $A_{2}$ or a according as c>0 or c<0.

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An efficient parallel solution algorithm on the linear second-order partial differential equations with large sparse matrix being based on the block cyclic reduction technique (Block Cyclic Reduction 기법에 의한 대형 Sparse Matrix 선형 2계편미분방정식의 효율적인 병렬 해 알고리즘)

  • 이병홍;김정선
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.15 no.7
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    • pp.553-564
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    • 1990
  • The co-efficient matrix of linear second-order partial differential equations in the general form is partitioned with (n-1)x(n-1) submartices and is transformed into the block tridiagonal system. Then the cyclic odd-even reduction technique is applied to this system with the large-grain data granularity and the block cyclic reduction algorithm to solve unknown vectors of this system is created. But this block cyclic reduction technique is not suitable for the parallel processing system because of its parallelism chanigng at every computing stages. So a new algorithm for solving linear second-order partical differential equations is presentes by the block cyclic reduction technique which is modified in order to keep its parallelism constant, and to reduce gteatly its execution time. Both of these algoriths are compared and studied.

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A study on the advanced RFID system using the parallel cyclic redundancy check (병렬 순환 잉여 검사를 이용한 발전된 무선인식 시스템에 관한 연구)

  • Kang Tai-Kyu;Yoon Sang-Mun;Shin Seok-kyun;Kang Min-Soo;Lee Key-Sea
    • Proceedings of the KSR Conference
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    • 2004.10a
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    • pp.1235-1240
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    • 2004
  • This paper has presented the parallel cyclic redundancy check (CRC) technique that performs CRC computation in parallel superior to the conventional CRC technique that processes data bits serially. Also, it has showed that the implemented parallel CRC circuit had been successfully applied to the inductively coupled passive RFID system working at a frequency of 13.56MHz in order to process the detection of logical faults more fast and the system had been verified experimentally. In comparison with previous works, the proposed RFID system using the parallel CRC technique has been shown to reduce the latency and increase the data processing rates in the results. Therefore, it seems reasonable to conclude that the parallel CRC realization in the RFID system offers a means of maintaining the integrity of data in the high speed RFID system.

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A Modified Parallel Iwan Model for Cyclic Hardening Behavior of Sand(I) : Model Development (수정 IWAN 모델을 이용한 사질토의 반복경화거동에 대한 연구(I): 모델 개발)

  • 이진선;김동수
    • Journal of the Earthquake Engineering Society of Korea
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    • v.7 no.5
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    • pp.47-56
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    • 2003
  • In this paper, the cyclic soil behavior model. which can accommodate the cyclic hardening, was developed by modifying the original parallel IWAN model. In order to consider the irrecoverable plastic strain of soil. the cyclic threshold strain, above which the backbone curve deviates from the original curve, was defined and the accumulated strain was determined by summation of the strains above the cyclic threshold in the stress-strain curve with applying Masing rule on unloading and reloading curves. The isotropic hardening elements are attached to the original parallel IWAN model and the slip stresses in the isotropic hardening elements are shown to increase according to the hardening functions. The hardening functions have a single parameter to account for the cyclic hardening and are defined by the symmetric limit cyclic loading test in forms of accumulated shear strain. The model development procedures are included in this paper and the verifications of developed model are discussed in the companion paper.

Efficient Parallel Block-layered Nonbinary Quasi-cyclic Low-density Parity-check Decoding on a GPU

  • Thi, Huyen Pham;Lee, Hanho
    • IEIE Transactions on Smart Processing and Computing
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    • v.6 no.3
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    • pp.210-219
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    • 2017
  • This paper proposes a modified min-max algorithm (MMMA) for nonbinary quasi-cyclic low-density parity-check (NB-QC-LDPC) codes and an efficient parallel block-layered decoder architecture corresponding to the algorithm on a graphics processing unit (GPU) platform. The algorithm removes multiplications over the Galois field (GF) in the merger step to reduce decoding latency without any performance loss. The decoding implementation on a GPU for NB-QC-LDPC codes achieves improvements in both flexibility and scalability. To perform the decoding on the GPU, data and memory structures suitable for parallel computing are designed. The implementation results for NB-QC-LDPC codes over GF(32) and GF(64) demonstrate that the parallel block-layered decoding on a GPU accelerates the decoding process to provide a faster decoding runtime, and obtains a higher coding gain under a low $10^{-10}$ bit error rate and low $10^{-7}$ frame error rate, compared to existing methods.

A Modified Parallel Iwan Model for Cyclic Hardening Behavior of Sand(II) : Verification (수정 IWAN 모델을 이용한 사질토의 반복경화거동에 대한 연구(II) : 모델 검증)

  • 이진선;김동수;추연욱;윤종구
    • Journal of the Earthquake Engineering Society of Korea
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    • v.7 no.5
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    • pp.57-66
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    • 2003
  • In order to verify the applicability of the developed modified parallel IWAN model. two types of cyclic torsional shear tests were performed using Kum-Kang and Toyoura sands. One was a symmetric-limit loading test and the other was an irregular loading test. Model parameters were derived from the symmetric limit loading tests at various relative densities and confining pressures. The modified parallel IWAN model can predict the cyclic hardening behavior of sands very well as increasing loading cycles in the symmetric-limit tests. Irregular loading tests were performed using the loading shape suggested by Pyke(1979). Cyclic behaviors under irregular loading were simulated using model parameters derived from symmetric limit loading test results of similar loading conditions. The predicted cyclic hardening behaviors under irregular loading matched well with experimental results and the applicability of the proposed model was verified.

REAL HYPERSURFACES IN THE COMPLEX HYPERBOLIC QUADRIC WITH CYCLIC PARALLEL STRUCTURE JACOBI OPERATOR

  • Jin Hong Kim;Hyunjin Lee;Young Jin Suh
    • Journal of the Korean Mathematical Society
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    • v.61 no.2
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    • pp.309-339
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    • 2024
  • Let M be a real hypersurface in the complex hyperbolic quadric Qm*, m ≥ 3. The Riemannian curvature tensor field R of M allows us to define a symmetric Jacobi operator with respect to the Reeb vector field ξ, which is called the structure Jacobi operator Rξ = R( · , ξ)ξ ∈ End(TM). On the other hand, in [20], Semmelmann showed that the cyclic parallelism is equivalent to the Killing property regarding any symmetric tensor. Motivated by his result above, in this paper we consider the cyclic parallelism of the structure Jacobi operator Rξ for a real hypersurface M in the complex hyperbolic quadric Qm*. Furthermore, we give a complete classification of Hopf real hypersurfaces in Qm* with such a property.