• Title/Summary/Keyword: Parallel model

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Revised Computational-GOMS Model for Drag Activity

  • Lee, Yong-Ho;Jeon, Young-Joo;Myung, Ro-Hae
    • Journal of the Ergonomics Society of Korea
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    • v.30 no.2
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    • pp.365-373
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    • 2011
  • The existing GOMS model overestimates the performance time of mouse activities because it describes them in a serial sequence. However, parallel movements of eye and hand(eye-hand coordination) have been dominant in mouse activities and this eye-hand coordination is the main factor for the overestimation of performance time. In this study, therefore, the revised CGOMSL model was developed to implement eye-hand coordination to the mouse activity to overcome one of the limitations of GOMS model, the lack of capability for parallel processing. The suggested revised CGOMSL model for drag activity, as an example for one of mouse activities in this study, begins visual search processing before a hand movement but ends the visual search processing with the hand movement in the same time. The results show that the revised CGOMSL model made the prediction of human performance more accurately than the existing GOMS model. In other words, one of the limitations of GOMS model, the incapability of parallel processing, could be overcome with the revised CGOMSL model so that the performance time should be more accurately predicted.

Study on Task Scheduling for Parallel Processing of Nested Loops (다중 루프문의 병렬처리를 위한 타스크 스케줄링에 관한 연구)

  • 허정연;손윤구
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.29B no.1
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    • pp.11-17
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    • 1992
  • This paper is to propose an analytical queuing model for parallel processing of sequential program with nested loops. The analytical results are compared with the results from the implemented multiprocessor system composed of four intel 8088 microprocessor, eight 2KB shared common memories, and a hardware token ring. At results, this study shows that the processed results are almost similar in proposed analytical model and real system. Proposed analytical model can be applied to evaluate parallel processing of sequential program with nested loops.

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Design of Parallel Type Fuzzy Controller Using Model Reference Plant (플랜트 모델참조를 이용한 병렬형 퍼지제어기 설계)

  • 추연규
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.5
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    • pp.379-383
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    • 2003
  • Parallel type fuzzy controller is designed by using a hybrid connected type fuzzy-PID controller and a model reference fuzzy controller. The first controller, consists of a fuzzy-PI and a fuzzy-PD making a hybrid type fuzzy-PID controller, plays a role as firstly reaching stable responses and secondly overcoming disturbance in plants. The second controller, model reference fuzzy controller, plays a role as reaching faster responses than other controllers. We have confirmed that the controller produces rapid and stable responses and overcomes disturbance by using parallel type fuzzy controller in a DC motor application.

DIRECT EPIPOLAR IMAGE GENERATION FROM IKONOS STEREO IMAGERY BASED ON RPC AND PARALLEL PROJECTION MODEL

  • Oh, Jae-Hong;Kim, Kyung-Ok
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.860-863
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    • 2006
  • Epipolar images have to be generated to stereo display aerial images or satellite images. Pushbroom sensor is used to acquire high resolution satellite images. These satellite images have curvilinear epipolar lines unlike the epipolar lines of frame images, which are straight lines. The aforementioned fact makes it difficult to generate epipolar images for pushbroom satellite images. If we assume a linear transition of the sensor having constant speed and attitude during image acquisition, we can generate epipolar images based on parallel projection model (2D Affine model). Recent high resolution images are provided with RPC values so that we can exploit these values to generate epipolar images without using ground control points and tie point. This paper provides a procedure based on the parallel projection model for generating epipolar images directly from a stereo IKONOS images, and experimental results.

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Direct Epipolar Image Generation From IKONOS Stereo Imagery Based On RPC and Parallel Projection Model

  • Oh, Jae-Hong;Shin, Sung-Woong;Kim, Kyung-Ok
    • Korean Journal of Remote Sensing
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    • v.22 no.5
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    • pp.451-456
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    • 2006
  • Epipolar images have to be generated to stereo display aerial images or satellite images. Pushbroom sensor is used to acquire high resolution satellite images. These satellite images have curvilinear epipolar lines unlike the epipolar lines of frame images, which are straight lines. The aforementioned fact makes it difficult to generate epipolar images for pushbroom satellite images. If we assume a linear transition of the sensor having constant speed and attitude during image acquisition, we can generate epipolar images based on parallel projection model (20 Affine model). Recent high resolution images are provided with RPC values so that we can exploit these values to generate epipolar images without using ground control points and tie point. This paper provides a procedure based on the parallel projection model for generating epipolar images directly from a stereo IKONOS images, and experimental results.

Numerical investigation of water-entry characteristics of high-speed parallel projectiles

  • Lu, Lin;Wang, Chen;Li, Qiang;Sahoo, Prasanta K.
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.13 no.1
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    • pp.450-465
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    • 2021
  • In this study, an attempt has been made to investigate the water-entry characteristics of the high-speed parallel projectile numerically. The shear stress transport k-𝜔 turbulence model and the Zwart-Gerber-Belamri cavitation model based on the Reynolds-Averaged Navier-Stokes method were used. The grid independent inspection and grid convergence index is carried out and verified. The influences of the parallel water-entry on flow filed characteristics, trajectory stability and drag reduction performance for different values of initial water-entry speed (𝜈0 = 280 m/s, 340 m/s, 400 m/s) and clearance between the parallel projectiles (Lp = 0.5D, 1.0D, 2.0D, 3.0D) are presented and analyzed in detail. Under the condition of the parallel water-entry, it can be found that due to the intense interference between the parallel projectiles, the distribution of cavity is non-uniform and part of the projectile is exposed to water, resulting in the destruction of the cavity structure and the decline of trajectory stability. In addition, the parallel projectile suffers more severe lateral force that separates the two projectiles. The drag reduction performance is impacted and the velocity attenuation is accelerated as the clearance between the parallel projectiles reduces.

Feasibility Study of a Distributed and Parallel Environment for Implementing the Standard Version of AAM Model

  • Naoui, Moulkheir;Mahmoudi, Said;Belalem, Ghalem
    • Journal of Information Processing Systems
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    • v.12 no.1
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    • pp.149-168
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    • 2016
  • The Active Appearance Model (AAM) is a class of deformable models, which, in the segmentation process, integrates the priori knowledge on the shape and the texture and deformation of the structures studied. This model in its sequential form is computationally intensive and operates on large data sets. This paper presents another framework to implement the standard version of the AAM model. We suggest a distributed and parallel approach justified by the characteristics of the model and their potentialities. We introduce a schema for the representation of the overall model and we study of operations that can be parallelized. This approach is intended to exploit the benefits build in the area of advanced image processing.

Implementation and Performance Analysis of a Parallel SIMPLER Model Based on Domain Decomposition (영역 분할에 의한 SIMPLER 모델의 병렬화와 성능 분석)

  • Kwak Ho Sang;Lee Sangsan
    • Journal of computational fluids engineering
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    • v.3 no.1
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    • pp.22-29
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    • 1998
  • Parallel implementation is conducted for a SIMPLER finite volume model. The present parallelism is based on domain decomposition and explicit message passing using MPI and SHMEM. Two parallel solvers to tridiagonal matrix equation are employed. The implementation is verified on the Cray T3E system for a benchmark problem of natural convection in a sidewall-heated cavity. The test results illustrate good scalability of the present parallel models. Performance issues are elaborated in view of convergence as well as conventional parallel overheads and single processor performance. The effectiveness of a localized matrix solution algorithm is demonstrated.

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Parallel Implementation of SIMPLER by Using Domain Decomposition Technique (영역분할법에 의한 SIMPLER 기법의 병렬화)

  • Kwak Ho Sang
    • 한국전산유체공학회:학술대회논문집
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    • 1997.10a
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    • pp.23-28
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    • 1997
  • A parallel implementation is made of a two-dimensional finite volume model based on the SIMPLER. The solution domain is decomposed into several subdomains and the solution at each subdomain is acquired by parallel use of multiple processors. Communications between processors are accomplished by using the standard MPI and the Cray-specific SHMEM. The parallelization method for the overall solution procedure to the Navier-Stokes equations is described in detail, The parallel implementation is validated on the Cray T3E system for a benchmark problem of natural convection in a sidewall-heated cavity. The parallel performance is assessed and the issues encountered in achieving a high-performance parallel model are elaborated.

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New execution model for CAPE using multiple threads on multicore clusters

  • Do, Xuan Huyen;Ha, Viet Hai;Tran, Van Long;Renault, Eric
    • ETRI Journal
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    • v.43 no.5
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    • pp.825-834
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    • 2021
  • Based on its simplicity and user-friendly characteristics, OpenMP has become the standard model for programming on shared-memory architectures. Checkpointing-aided parallel execution (CAPE) is an approach that utilizes the discontinuous incremental checkpointing technique (DICKPT) to translate and execute OpenMP programs on distributed-memory architectures automatically. Currently, CAPE implements the OpenMP execution model by utilizing the DICKPT to distribute parallel jobs and their data to slave machines, and then collects the results after executing these distributed jobs. Although this model has been proven to be effective in terms of performance and compatibility with OpenMP on distributed-memory systems, it cannot fully exploit the capabilities of multicore processors. This paper presents a novel execution model for CAPE that utilizes two levels of parallelism. In the proposed model, we add another level of parallelism in the form of multithreaded processes on slave machines with the goal of better exploiting their multicore CPUs. Initial experimental results presented near the end of this paper demonstrate that this model provides significantly enhanced CAPE performance.