• Journal of the Korea Society for Simulation
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• v.12 no.2
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• pp.35-44
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• 2003

The effectiveness of buffer cache replacement algorithms is critical to the performance of I/O systems. In this paper, we propose the degree of inter-reference gap (DIG) based block replacement scheme that retains merits of the least recently used (LRU) such as simple implementation and good cache hit ratio (CHR) for general patterns of references, and improves CHR further. In the proposed scheme, cache blocks with low DIGs are distinguished from blocks with high DIGs and the replacement block is selected among high DIGs blocks as done in the low inter-reference recency set (LIRS) scheme. Thus, by having the effect of the partitioning the cache memory dynamically based on DIGs, CHR is improved. Trace-driven simulation is employed to verified the superiority of the DIG based scheme and shows that the performance improves up to about 175% compared to the LRU scheme and 3% compared to the LIRS scheme for the same traces.

• The Transactions of the Korea Information Processing Society
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• v.7 no.3
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• pp.935-942
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• 2000

In this paper we introduce a fast simplification algorithm for terrain height fields to produce a triangulated irregular network, based on the greedy insertion algorithm in [1,4,5]. Our algorithm partitions a terrain height data into rectangular blocks with the same size ad simplifies blocks one by one with the greedy insertion algorithm. Our algorithm references only to the points and the triangles withing each current block for adding a point into the triangulation. Therefore, the algorithm runs faster than the greedy insertion algorithm, which references all input points and triangles in the terrain. Our experiment shows that partitioning method runs from 4 to more than 20 times faster, and it approximates test height fields as accurately as the greedy insertion algorithms. Most greedy insertion algorithms suffer from elongated triangles that usually appear near the boundaries. However, we insert the four corner points into each block to produce the base triangulation of the block before the point addition step begins so that elongated triangles could not appear in th simplified terrain.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.6A
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• pp.565-572
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• 2007

3G Long Term Evolution (3G LTE) is a next generation cellular networks system capable or providing various mobile multimedia services by using OFDMA and MIMO based radio access technology. Among many differences from existing WCDMA based systems, the facts that 3G LTE uses Physical Resource Block (PRB) as its radio resources and provides all services through the PS domain make the development of new resource management schemes necessary. This paper proposes an adaptive partitioning based downlink call admission control scheme. It separates realtime call requests from non-realtime ones, specifies maximum allowable resource amounts for each type, but if the maximum is exceeded, call requests are accepted with probability proportional to remaining resource amounts. Despite the fact that such adaptive concept has been already adopted by other call admission schemes, the contributions of our paper, which are that we are able to find an efficient way to apply the proposed scheme exploiting PRB characteristics and measure the resource usage of base stations by PRB utilization and payload ratio, are still valid. When judging from simulation results in comparison with others, our scheme is able to prioritize realtime call requests over non-realtime ones, and at the same time, overall system performance is superior.

• Journal of Broadcast Engineering
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• v.27 no.3
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• pp.361-368
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• 2022

Quaternary tree plus multi-type tree (QT+MTT) structure was adopted in the Versatile Video Coding (VVC) standard as a block partitioning tool. QT+MTT provides excellent coding gain; however, it has huge encoding complexity due to the flexibility of the binary tree (BT) and ternary tree (TT) splits. This paper proposes a fast inter coding unit (CU) partitioning algorithm for BT and TT split types based on prediction accuracy functions using the mean of the absolute error (MAE). The MAE-based decision model was established to achieve a consistent time-saving encoding with stable coding loss for a practical low complexity VVC encoder. Experimental results under random access test configuration showed that the proposed algorithm achieved the encoding time saving from 24.0% to 31.7% with increasing luminance Bjontegaard delta (BD) rate from 1.0% to 2.1%.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1996.04a
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• pp.465-468
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• 1996

We deal with facility layout problems with shape constraints. A simulated annealing algorithm is developed for the problems. In the algorithm, a solution is encoded as a matrix that has information about relative locations of the facilities in the floor. A block layout is constructed by partitioning the floor into a set of rectangular blocks according to the information while satisfying areas of facilities. In this paper, three methods are suggested for the partitioning procedure and they are employed in the simulated annealing algorithm. Results of computational experiments show that the proposed algorithm performs better than existing algorithms, especially for problems with tight shape constraints.

• Proceedings of the IEEK Conference
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• 2003.11a
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• pp.133-136
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• 2003

In this paper, we propose a low bit-rate embedded video coding scheme with 3-D block partition in the wavelet domain. The proposed video coding scheme includes multi-level three dimensional dyadic wavelet decomposition, raster scanning within each subband, partitioning of blocks, and adaptive arithmetic entropy coding. Although the proposed video coding scheme is quite simple, it produces bit-streams with good features, including SNR scalability from the embedded nature. Experimental results demonstrate that the proposed video coding scheme is quite competitive to other good wavelet-based video coders in the literature.

• Proceedings of the KIEE Conference
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• 2004.11c
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• pp.190-192
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• 2004

In this paper, we propose a low bit-rate embedded video compression scheme with 3-D block partition coding in the wavelet domain. The proposed video compression scheme includes multi-level 3-dimensional dyadic wavelet decomposition, raster scanning within each subband, formation of block, 3-D partitioning of block, and adaptive arithmetic entropy coding. Although the proposed video compression scheme is quit simple, it produces bit-stream with good features, including SNR scalability from the embedded nature. Experimental results demonstrate that the proposed video compression scheme is quit competitive to other good wavelet-based video coders in the literature.

• Journal of Korea Multimedia Society
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• v.7 no.8
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• pp.1183-1194
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• 2004

Network partitioning problem is to partition a network into multiple blocks such that the size of cutset is minimized while keeping the block sizes balanced. Among these, iterative algorithms are regarded as simple and efficient which are based on cell move of Fiduccia and Mattheyses algorithm, Sanchis algorithm, or Kernighan and Lin algorithm. All these algorithms stipulate balanced block size as a constraint that should be satisfied, which makes a cell movement be inefficient. Park and Park introduced a balancing coefficient R by which the block size balance is considered as a part of partitioning cost, not as a constraint. However, Park and Park's algorithm has a square time complexity with respect to the number of cells. In this paper, we proposed Bucket algorithm that has a linear time complexity with respect to the number of cells, while taking advantage of the balancing coefficient. Reducing time complexity is made possible by a simple observation that balancing cost does not vary so much when a cell moves. Bucket data structure is used to maintain partitioning cost efficiently. Experimental results for MCNC test sets show that cutset size of proposed algorithm is 63.33% 92.38% of that of Sanchis algorithm while our algorithm satisfies predefined balancing constraints and acceptable execution time.

• 전기의세계
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• v.18 no.6
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• pp.33-45
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• 1969

The purpose of this paper is design the most important part of sequential control systems, that is, command-treatment part, from the signal-transformation point of view. An orderly procedure is developed by which for sequential control systems the experimental design method can be reduced to the rational design method. Important in this procedure are: 1. To make total block diagram of sequential control systems by determining input and output signals of command-treatment part. 2. To partition over-all block diagram by observing each output signal. 3. To design concretely minimum block diagram by using the operational block diagram. By applying the method for partitioning the circuit to the design, the design method for sequential control systems is organized and done rationally without the aid of experiece.

• Journal of Multimedia Information System
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• v.4 no.1
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• pp.19-26
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• 2017

The compression of video for both full HD and UHD requires the inclusion of extra vertical lines to every video frame, named as the DTV essential hidden area (DEHA), for the effective functioning of the MPEG-2/4/H encoder, stream, and decoder. However, while the encoding/decoding process is dependent on the DEHA, the DEHA is conventionally viewed as a redundancy in terms of channel utilization or storage efficiency. This paper proposes a block mode DEHA method to more effectively utilize the DEHA. Partitioning video block images and then evenly filling the representative DEHA macroblocks with the average DC coefficient of the active video macroblock can minimize the amount of DEHA data entering the compressed video stream. Theoretically, this process results in smaller DEHA data entering the video stream. Experimental testing of the proposed block mode DEHA method revealed a slight improvement in the quality of the active video. Outside of this technological improvement to video quality, the attractiveness of the proposed DEHA method is also heightened by the ease that it can be implemented with existing video encoders.