• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.7
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• pp.9-14
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• 2003

In this work, a multi-block/multi-partitioning method is suggested for a multi-block parallelization. It has an advantage of uniform load balance via subdividing of each block on each processor. To make a comparison of parallel efficiency according to domain decomposition method, a multi-block/single-partitioning and a multi-block/ multi-partitioning methods are applied to the flow analysis solver. The multi-block/ multi-partitioning method has more satisfactory parallel efficiency because of optimized load balancing. Finally, it has applied to the CFDS code. As a result, the computing speed with sixteen processors is over twelve times faster than that of sequential solver.

• Journal of Broadcast Engineering
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• v.25 no.5
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• pp.698-708
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• 2020

VVC (Versatile Video Coding), which has been developing as a next generation video coding standard. Compared to HEVC (High Efficiency Video Coding), VVC is improved by about 34% in RA (Random Access) configuration and about 30% in LDB (Low-Delay B) configuration by adopting various techniques such as recursive block partitioning structure and GPM (Geometric Partitioning Mode). But the encoding complexity is increased by about 10x and 7x, respectively. In this paper, we propose a fast decision method of GPM mode and block partitioning using directionality of block to reduce encoding complexity of VVC. The proposed method is to apply the Hough transform to the current block to identify the directionality of the block, thereby determining the GPM mode and the specific block partitioning method to be skipped in the rate-distortion cost search process. As a result, compared to VTM8.0, the proposed method reduces about 31.01% and 29.84% encoding complexity for RA and LDB configuration with 2.48% and 2.69% BD-rate loss, respectively.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2003.10a
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• pp.229-235
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• 2003

Research of basis technology to construct the human haplotype map is one of active areas in SNP post-genomics research. Identification of haplotype block structure from haplotype data is key step in the haplotype map project. Several algorithms have been proposed for the block identification, including the greedy algorithm, and the dynamic programming based algorithm. This paper analyzed block partitioning method of several algorithm which has been proposed in recent years. HapBlock and HaploBlockFinder are programs used in our experiment.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.5
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• pp.85-91
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• 2015

This paper presents a novel frame rate up-conversion (FRUC) algorithm. Existing algorithms, in general, employ rectangular blocks for motion estimation and arbitrary shape of an actual object region cannot be precisely represented. On the other hand, the proposed wedge-shaped block partitioning algorithm partitions a rectangular block into two wedge-shaped blocks using the texture information, which makes better approximation for an actual object region. The wedge-shaped block partitioning algorithm as well as the adaptive motion vector prediction algorithm is used to reliably estimate the actual motion. Experimental results show that the proposed FRUC algorithm is superior to existing algorithms up to 1.988dB in PSNR and 0.0167 in SSIM comparisons.

• ETRI Journal
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• v.43 no.2
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• pp.313-323
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• 2021

The Joint Video Exploration Team (JVET) has studied future video coding (FVC) technologies with a potential compression capacity that significantly exceeds that of the high-efficiency video coding (HEVC) standard. The joint exploration test model (JEM), a common platform for the exploration of FVC technologies in the JVET, employs quadtree plus binary tree block partitioning, which enhances the flexibility of coding unit partitioning. Despite significant improvement in coding efficiency for chrominance achieved by separating luminance and chrominance tree structures in I slices, this approach has intrinsic drawbacks that result in the redundancy of block partitioning data. In this paper, an adaptive tree structure correlating luminance and chrominance of single and dual trees is presented. Our proposed method resulted in an average reduction of -0.24% in the Y Bjontegaard Delta rate relative to the intracoding of JEM 6.0 common test conditions.

• Bulletin of the Korean Chemical Society
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• v.29 no.10
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• pp.2047-2050
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• 2008

• Journal of Communications and Networks
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• v.9 no.1
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• pp.11-17
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• 2007

In this paper, system performance of turbo trellis coded modulation (turbo TCM) is presented and analyzed through computer simulations over two typical channels, namely additive white Gaussian noise (AWGN) and Rayleigh fading channels. We use and compare different mapping strategies based on Ungerboeck partitioning (UP), block partitioning (BP), mixed partitioning (MP), Gray partitioning (GP), and Ungerboeck-Gray partitioning (UGP) of the signal constellation of the turbo TCM system. Furthermore, taking 8PSK modulation of turbo TCM as an example, our simulation results show that turbo TCM with UP can obtain better performance than turbo TCM with BP, MP, GP, and UGP in both AWGN and Rayleigh fading channels.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.6
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• pp.8-16
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• 2003

Aerodynamic characteristics over Micro Aerial Vehicle(MAV) in low Reynolds number regime are numerically studied using 3-D unsteady, incompressible Navier-Stokes flow solver with single partitioning method for multi-block grid. For more efficient computation of unsteady flows, this flow solver is parallel-implemented with MPl(Message Passing Interface) programming method. Firstly, MAV wing with not complex geometry is considered and then, we analyze aerodynamic characteristics over full MAV configuration varying the angle of attack. Present computational results show a better agreement with the experimental data by MACDL(Micro Aerodynamic Control and Design Lab.), Seoul National University. We can also find the conceptually designed MAV by MACDL has the static stability.

• Proceedings of the IEEK Conference
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• 2001.09a
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• pp.125-128
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• 2001

본 논문은 파동분할(Wave partitioning) 방식을 이용한 순차적(Sequential) 메쉬 부호화 방식을 제안한다. 파동분할 방식은 호수에 물방울이 퍼져 나가는 자연 원리를 이용하여 초기 삼각형의 주위에 삼각형을 덧붙여 가면서 하나의 SPB(Small Processing Block)을 만들어내는 방식이다. 이 방식을 이용하여 하나의 모델을 서로 독립적인 SPB로 분할하고, 각각의 SPB 내에서 초기 삼각형을 중심으로 그것에 덧붙여진 삼각형에 의해 만들어진 원 또는 반원을 찾는다. 또한 그 원주를 따라 순차적으로 꼭지점을 구하면 각각의 꼭지점들은 일정한 패턴으로 늘어서게 되고, 이를 이용하여 연결성 정보 없이 부가 정보만 이용하여 모델을 순차적으로 무손실 부호화한다.

• Proceedings of the IEEK Conference
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• 1998.10a
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• pp.1157-1160
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• 1998

This paper describes the design of a block data flow architecture(BDFA) which implements 2-D discrete wavelet transform(DWT)/inverse discrete wavelet transform(IDWT) for real time image processing applications. The BDFA uses 2-D product separable filters for DWT/IDWT. It consists of an input module, a processor array, and an output module. It use both data partitioning and algorithm partitioning to achieve high efficiency and high throughput. The 2-D DWT/IDWT algorithm for 256$\times$256 lenna image has been simulated using IDL(Interactive Data Language). The 2-D array structured BDFA for the 2-D filter has been modeled and simulated using VHDL.