• 제목/요약/키워드: parallel communication

검색결과 1,116건 처리시간 0.024초

Optimized Algebra LDPC Codes for Bandwidth Efficient Modulation

  • Hwang, Gi-Yean;Yu Yi;Lee, Moon-Ho
    • Journal of electromagnetic engineering and science
    • /
    • 제4권1호
    • /
    • pp.17-22
    • /
    • 2004
  • In this paper, we implement an efficient MLC/PDL system for AWGN channels. In terms of the tradeoff between the hardware implementation and system performance, proposed algebra LDPC codes are optimized by the Gaussian approximation(GA) according to the rate of each level assigned by the capacity rule and chosen as the component code. System performance with Ungerboeck Partitioning(UP), Miked Partitioning(MP) and Gray Mapping(GM) of 8PSK are evaluated, respectively. Many results are presented in this paper; they can indicate that the proposed MLC/PDL system using optimized algebra LDPC codes with different code rate, capacity rule and Gray mapping(GM) can achieve the best performance.

Design of Modified Banyan Switch for High Speed Communication Network

  • Kwon, Seung-Tag;Sam-Ho cho
    • Proceedings of the IEEK Conference
    • /
    • 대한전자공학회 2000년도 ITC-CSCC -1
    • /
    • pp.537-540
    • /
    • 2000
  • In this paper, we propose and design new architecture of the modified Banyan switch for a high speed networking and the high speed parallel computer. The proposed switching network with a remodeled architecture is a newly modified Banyan network with eight input and output ports. The switch scheme is that two packets may arrive on different inputs destined for the same output. We have analyzed the maximum throughput of the revised switch. The result of the analyses shows good agreement simulation and if we adopt such architecture of the revised model of the Banyan switch, the hardware complexity can be reduced. The FIFO discipline has increased about lloio when we compare the switching system with the input buffer system. We have designed and verified the switching system in VHDL.

  • PDF

COMPUTATION OF INDUCTIVE COUPLING BETWEEN ELECTRIFIED RAILWAYS AND COMMUNICATION CABLES (전철시스템에서 전차선로와 통신선로간 유도전압의 해석)

  • Song, Jin-Ho;Lee, Hyung-Soo;Ryu, Keun-Bai;Chang, Sang-Hoon
    • Proceedings of the KIEE Conference
    • /
    • 대한전기학회 1999년도 하계학술대회 논문집 A
    • /
    • pp.436-439
    • /
    • 1999
  • This paper present a study on the interference levels on the communication lines, which are parallel to the electrified rails. The interference study is carried out using a circuit model approach. First, the self and shunt impedances of all the conductors in the rail system and the mutual impedances between different conductors are computed. Several different scenarios are analyzed, including the load condition and a few fault conditions with different fault locations. The induced potentials on the communication cables are computed. The effect of the buried ground wires is also analyzed by comparing the results with and without the presence of the ground wires. The results presented in the paper can be used as a reference for estimating interference levels in similar rail systems.

  • PDF

Load Balancing for the Efficient Parallelization in the Grid (그리드 환경하의 효율적 해석을 위한 작업 분할 기법 연구)

  • Ko Soon-Heum;Jung Myungwoo;Kim Chongam;Rho Oh-Hyun;Lee Sangsan
    • 한국전산유체공학회:학술대회논문집
    • /
    • 한국전산유체공학회 2003년도 추계 학술대회논문집
    • /
    • pp.63-68
    • /
    • 2003
  • The Grid[1] is a communication service that collaborates dispersed high performance computers so that those can be shared and worked together. So, the Grid enables a researcher to analyze a huge-sized problem which was impossible by using local resources. However, diverse communication speeds among computing resources and heterogeneity of computing resources can reduce parallel efficiency in the Grid, The present paper focuses on the development of an efficient load balancing algorithm suitable for the Grid. Proposed algorithm classifies the whole processors into several groups with relatively faster communication speeds. Computational domain is firstly partitioned to each group and then to the processor level considering the performance of each processor. Developed algorithm is validated in the homogeneous system by comparing the present result with the result of equally partitioned meshes and then applied to the heterogeneous system. Additionally, the present algorithm is expanded to be able to solve the decomposed domains and applied to some problems.

  • PDF

DESIGN AND IMPLEMENTATION OF THE ALL DIGITAL QPSK TRANSMITTER FOR MPEG-2 PACKETS SUPPORTING THE DAVIC STANDARD

  • Park, Sungsoo;Lee, Youngkou;Kim, Kiseon
    • Proceedings of the IEEK Conference
    • /
    • 대한전자공학회 2000년도 ITC-CSCC -2
    • /
    • pp.914-918
    • /
    • 2000
  • In this paper, a next generation high speed QPSK transmitter is designed based on 1.8${\mu}$m design rule. The designed transmitter supports the MPEG2-TS coded packed data for the DAVIC standard. Transmitter is composed of the convolutional coder, the shortened Reed-Solomon coder, and QPSK modulator. The coded packets are modulated in APSK with an RC filter. Especially, Galois Field multiplier with a standard basis is designed with the pipelined parallel architecture. Also, in the QPSK modulator, the RC filter and mixer are simplified into the ROM table, which can improve the performance of the transmitter. The total number of gates for the implemented baseband transmitter is 26,875.

  • PDF

SOC Test Compression Scheme Sharing Free Variables in Embedded Deterministic Test Environment

  • Wang, Weizheng;Cai, Shuo;Xiang, Lingyun
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • 제15권3호
    • /
    • pp.397-403
    • /
    • 2015
  • This paper presents a new SOC test compression scheme in Embedded Deterministic Test (EDT) compression environment. Compressed test data is brought over the TAM from the tester to the cores in SOC and decompressed in the cores. The proposed scheme allows cores tested at the same time to share some test channels. By sharing free variables in these channels across test cubes of different cores decompressed at the same time, high encoding efficiency is achieved. Moreover, no excess control data is required in this scheme. The ability to reuse excess free variables eliminates the need for high precision in matching the number of test channels with the number of care bits for every core. Experimental results obtained for some SOC designs illustrate effectiveness of the proposed test application scheme.

Object Extraction technique Using Belief Propagation Stereo Algorithm of Bidirectional Search based on Brightness (밝기기반 양방향 탐색기법의 신뢰전파 스테레오 알고리즘을 이용한 물체 추출 기법)

  • Choi, Young-Seok;Choi, Kyung-Seok;Kang, Hyun-Soo
    • Proceedings of the IEEK Conference
    • /
    • 대한전자공학회 2007년도 하계종합학술대회 논문집
    • /
    • pp.313-314
    • /
    • 2007
  • In this paper, we suggest robust object extraction algorithm taking advantage of efficient Belief Propagation method. It does not get a disparity information because of uniform region and occlusion region etc. on initial depth map that use forward direction disparity information although is object area. Therefore, We run parallel backward disparity information and brightness information for certain object extraction.

  • PDF

A Parallel Approach on the B-tree for an Information Retrieval System using FAST-INV (FAST-lNV를 이용한 정보검색 시스템에서의 B-트리의 병렬접근에 대한 연구)

  • Kim, Soo-Young;Goh, Ji-Hyun;Park, Soon-Chol
    • Proceedings of the Korea Information Processing Society Conference
    • /
    • 한국정보처리학회 2001년도 추계학술발표논문집 (상)
    • /
    • pp.263-266
    • /
    • 2001
  • 인터넷 상의 문서양이 기하급수적으로 증가하면서 검색엔진의 성능평가가 대두되고 있다. 이를 위해 검색엔진 인덱스 모듈부분의 좋은 성능이 요구되는데 빠른 대용량 역파일 구성을 위한 알고리즘을 사용하게 되면 인덱스 속도를 향상시킬 수 있다. 그러나, 병렬처리가 되지 않는 문헌벡터화일 제작시 트리검색 모듈에서 병목 현상이 발생하게 된다. 본 논문에서는 병목현상이 발생하는 트리를 병렬로 접근함으로써 시스템의 병목현상을 해소하고 인덱스 시스템의 전체적인 성능을 개선찬 수 있는 방안을 연구한다.

  • PDF

Metaheuristic Optimization Techniques for an Electromagnetic Multilayer Radome Design

  • Nguyen, Trung Kien;Lee, In-Gon;Kwon, Obum;Kim, Yoon-Jae;Hong, Ic-Pyo
    • Journal of electromagnetic engineering and science
    • /
    • 제19권1호
    • /
    • pp.31-36
    • /
    • 2019
  • In this study, an effective method for designing an electromagnetic multilayer radome is introduced. This method is achieved by using ant colony optimization for a continuous domain in the transmission coefficient maximization with stability for a wide angle of incidence in both perpendicular and parallel polarizations in specific X- and Ku-bands. To obtain the optimized parameter for a C-sandwich radome, particle swarm optimization algorithm is operated to give a clear comparison on the effectiveness of ant colony optimization for a continuous domain. The qualification of an optimized multilayer radome is also compared with an effective solid radome type in transmitted power stability and presented in this research.

Remote Parallel Pseudo-Dynamic Testings Using Internet on Base Isolated Bridge (인터넷을 이용한 원격병렬 유사동적실험 : 면진교량에 대하여)

  • 윤정방;김재민;김남식;심종민;구기영
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 한국전산구조공학회 2000년도 봄 학술발표회논문집
    • /
    • pp.304-307
    • /
    • 2000
  • This paper presents a numerical simulation study for remote parallel pseudo-dynamic testings using Internet. In this testing method, experimental facilities located at different places can be parallelly used for testing a large-scale structure with many components subjected to severe nonlinear behavior. Example analysis is carried out on a base- isolated bridge for earthquake loading. The results indicate that the time required for data communication between two facilities located 250km apart through Internet for t 000 time steps is about 20 minutes, which is fairly equivalent to the time required for pseudo-dynamic testing. This testing method can be more powerful, as the data transmitting technique through Internet improves.

  • PDF