• Title/Summary/Keyword: Thread

Search Result 1,128, Processing Time 0.026 seconds

The implementation of the Communication Kernel on IXP1200 (IXP1200 네트워크 프로세서를 이용한 Communication Kernel의 구현)

  • 황광섭;백성찬;박우진;정영환;안순신
    • Proceedings of the Korean Information Science Society Conference
    • /
    • 2002.04a
    • /
    • pp.313-315
    • /
    • 2002
  • 인터넷의 급격한 성장과 함께 네트워크 서비스에 대한 사용자의 요구도 점점 증대되고 있다. 이러한 시장의 요구에 빠르게 대응하고 새로운 특징에 대한 시스템의 수정과 보완이 용이하게 되도록 고안된 것이 네트워크 프로세서이며, 본 논문에서는 인텔사의 IXP1200 네트워크 프로세서를 이용하여 기본적인 IP패킷 포워딩기능을 수행하는 Communication kernel을 구현한다. 우리의 구현에서는 8개의 slow port와 1개의 fast port가 하나의 queue를 공유하며, Receive thread가 이 queue를 공유하도록 한다. Communication kernel은 receive scheduler, receive thread, transmit scheduler, transmit thread의 네 개의 모듈로 구성 되어진다.

  • PDF

A Design of a 8-Thread Graphics Processor Unit with Variable-Length Instructions

  • Lee, Kwang-Yeob;Kwak, Jae-Chang
    • Journal of information and communication convergence engineering
    • /
    • v.6 no.3
    • /
    • pp.285-288
    • /
    • 2008
  • Most of multimedia processors for 2D/3D graphics acceleration use a lot of integer/floating point arithmetic units. We present a new architecture with an efficient ALU, built in a smaller chip size. It reduces instruction cycles significantly based on a foundation of multi-thread operation, variable length instruction words, dual phase operation, and phase instruction's coordination. We can decrease the number of instruction cycles up to 50%, and can achieve twice better performance.

Implementation of Parallel Task Creation Mechanism in POSOX Thread (POSIX Thread를 이용한 병렬 태스크 생성 메커니즘의 구현)

  • 윤봉식;황선태
    • Proceedings of the Korean Information Science Society Conference
    • /
    • 1999.10c
    • /
    • pp.759-761
    • /
    • 1999
  • 본 논문에서는 동적 병렬 태스크를 추출하는 메커니즘을 공유 메모리 구조상에서 구현하는데 있어서 최적화 기법에 대해서 소개한다. 최대의 호환성을 고려하여 POSIX thread와 C언어를 사용하였는데 이에 따른 오버헤드를 여러 가지 구현 기법을 사용하여 줄이고자 노력하였다. 그리고 병렬 처리시 대부분의 계산은 각 처리기에서 순차 계산에 의해 이루어지므로 이 순차 계산시에 발생하는 오버헤드를 줄이는 것을 최우선으로 하였다.

  • PDF

The design of the Receive Thread in IXP1200 Network Processor (IXP1200 네트워크 프로세서를 이용한 Receive Thread의 설계)

  • 박우진;이병재;왕명안;황광섭;안순신
    • Proceedings of the Korean Information Science Society Conference
    • /
    • 2001.10c
    • /
    • pp.178-180
    • /
    • 2001
  • 인터넷의 급격한 성장과 함께 네트워크 서비스에 대한 사용자의 요구도 점점 증대되고 있다. 이러한 시장의 요구에 빠르게 대응하고 새로운 특징에 대한 시스템의 수정과 보완이 용이하게 되도록 고안된 것이 네트워크 프로세서이며, 본 논문은 인텔의 IXP1200 네트워크 프로세서를 이용한 포워딩 엔진의 한 모듈인 Receive Thread를 설계한다.

  • PDF

Research on Optimal Taper Stud Bolts for Steam Turbines Using the FEM (유한요소법을 이용한 증기터빈용 최적 테이퍼 스터드 볼트에 관한 연구)

  • 이부윤;김태완
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.24 no.2
    • /
    • pp.8-16
    • /
    • 2000
  • The thread load distribution as applied to large stud bolts for steam turbines is investigated using the finite element method. The stress concentration in tapered threads is studied with varying prestress and taper angle. Based upon the thread load distribution, the optimal taper angles to reduce the stress concentration are determined for various prestresses. The presented finite element model is validated by comparing results of the calculated thread load with analytic ones. The optimal taper angles obtained from this research can be used in designing tapered threads of large stud bolts for steam turbines.

  • PDF

Experimental study on stripping mechanism of tension controlled bolts (TC볼트의 스트리핑 메카니즘에 대한 실험적 연구)

  • 신근하
    • Journal of the Korean Society of Manufacturing Technology Engineers
    • /
    • v.9 no.1
    • /
    • pp.111-118
    • /
    • 2000
  • Over tightening experiments of the tension-controlled bolts are carried out and the stripping mechanism is reviewed base on the observed results. There are two modes of bolt failure due to the over tightening : one the fracture of the bolt the other the thread stripping Bifurcation between these two modes is rather delicate but it seems being related with the elastic flexibility of the bolt which depends upon the unused thread length. The fracture mode occurs in the bolts with good flexibility while the latter with bad one. According to the ISO Standard some meter coarse threads like M20 and M22 have the same pitch which causes bigger fastener to less resistance in shear and bending compared with the smaller one. however since UNC thread system adapts different pitch for different nominal diameter unified coarse threads show better stripping resistance than their corresponding meter threads.

  • PDF

Effective method of accessing SHORE volumes (효과적인 SHORE 볼륨 접근 방법)

  • Ahn, Sung-Soo;Choi, Yun-Soo;Jin, Du-Seok
    • Proceedings of the Korea Information Processing Society Conference
    • /
    • 2002.11c
    • /
    • pp.1815-1818
    • /
    • 2002
  • 사용자에게 서비스 할 데이터가 많을 경우 데이터베이스의 여러 볼륨에 저장해서 처리해야 할 경우가 발생한다. 볼륨이 여러 개일 경우 효과적이고 효율적인 접근 방법이 필요하다. 본 논문에서는 SHORE 저장 시스템을 이용할 경우에 효과적이고 효율적인 접근 방법을 알아보고자 한다. single thread, multi thread, multi process, socket 을 이용한 접근 방법을 살펴보고 multi thread 를 이용하는 방법이 가장 효율적인 것을 실험 결과를 통해서 보인다. SHORE thread 는 CPU bound 에 과련된 job 이 많은 경우는 process 를 사용했을 때에 비해 큰 효과가 없으나 I/0 bound 에 관련에 것일 경우는 multi process 를 사용한 것과 비슷한 효과가 있음을 알 수 있다.

  • PDF

Multi-Thread based Synchronization of Locomotion Control in Snake Robots

  • Rai, Laxmisha;Kang, Soon-Ju
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2005.06a
    • /
    • pp.947-950
    • /
    • 2005
  • In this paper, we present an approach to control the locomotion of snake robot with concurrent programming model constructed using threads and semaphores. The multi-thread based concurrent programming model adds the flexibility to design and synchronize the movement of snake robots as compared with microcontroller and mechanical based approaches. We have designed a physical snake robot using LEGO sensors and actuator blocks and the wave motion of the snake robot is generated by multi-thread based concurrent programming under RT-Linux. The different robot movements in a desired direction along with different types of snake movements are achieved using angle sensors.

  • PDF

An Implementation of Single Stack Multi-threading for Small Embedded Systems

  • Kim, Yong-Seok
    • Journal of the Korea Society of Computer and Information
    • /
    • v.21 no.4
    • /
    • pp.1-8
    • /
    • 2016
  • In small embedded systems including IoT devices, memory size is very small and it is important to reduce memory amount for execution of application programs. For multi-threaded applications, stack may consume a large amount of memory because each thread has its own stack of sufficiently large size for worst case. This paper presents an implementation of single stack multi-threading, called SSThread (Single Stack Thread), by sharing a stack for all threads to reduce stack memory size. By using SSThread, multi-threaded applications can be programmed based on normal C language environment and there is no requirement of transporting multi-threading operating systems. It consists of several library functions and various C macro definitions. Even though some functional restrictions in comparison to operating systems supporting complete multi-thread functionalities, it is very useful for small embedded systems with tiny memory size and it is simple to setup programming environment for multi-thread applications.

Strain hardening behavior of linear polymer melts

  • Hong Joung Sook;Ahn Kyung Hyun;Lee Seung Jong
    • Korea-Australia Rheology Journal
    • /
    • v.16 no.4
    • /
    • pp.213-218
    • /
    • 2004
  • Linear high-density polyethylene (PE) was controlled to induce strain-hardening behavior by introducing a small amount of second component with an anisotropic structure. In order to form an anisotropic structure in the PE matrix, the polymer was extruded through a twin-screw extruder, and the structure was controlled by varying the extrusion conditions. Depending on conditions, the second component formed a film, thread and droplet structure. If the second component was kept rigid, the morphology evolution could be delayed and the second component could maintain its film or thread structure without further relaxation. In par­ticular, the second component of the thread structure made a physical network and gave rise to remarkable strain hardening behavior under high extension. This study suggests a new method that induces strain hard­ening behavior by introducing a physically networked second component into the linear polymer melt. This result is anticipated to improve the processibility of linear polymers especially when extensional flow is dominant, and to contribute to our understanding of strain hardening behavior.