• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.35 no.2C
• /
• pp.172-181
• /
• 2010

In this paper, we propose an adaptive block quantization method. The propose method perfrect reconstructs side information without high complexity in the encoder side, as transmitting motion vectors from a decoder to an encoder side. Also, at the encoder side, residual signals between reconstructed side information and original frame are adaptively quantized to minimize parity bits to be transmitted to the decoder. The proposed method can effectively allocate bits based on bit error rate of side information. Also, we can achieved bit-saving by transmission of parity bits based on the error correction ability of the LDPC channel decoder, because we can know bit error rate and positions of error bit in encoder side. Experimental results show that the proposed algorithm achieves bit-saving by around 66% and delay of feedback channel, compared with the convntional algorithm.

• Journal of Biomedical Engineering Research
• /
• v.18 no.3
• /
• pp.223-231
• /
• 1997

In this paper, an interframe coding method for volumetric medical images is proposed. By treating interslice variations as the motion of bones or tissues, we use the motion compensation (MC) technique to predict the current frame from the previous frame. Instead of a block matching algorithm (BMA), which is the most common motion estimation (ME) algorithm in video coding, image warping with biolinear transformation has been suggested to predict complex interslice object variation in medical images. When an object disappears between slices, however, warping prediction has poor performance. In order to overcome this drawback, an overlapped block motion compensation (OBMC) technique is combined with carping prediction. Motion compensated residual images are then encoded by using an embedded zerotree wavelet (EZW) coder with small modification for consistent quality of reconstructed images. The experimental results show that the interframe coding suing warping prediction provides better performance compared with interframe coding, and the OBMC scheme gives some additional improvement over the warping-only MC method.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.13 no.11
• /
• pp.5389-5396
• /
• 2012

In this paper, an optimized residual data decoder architecture is proposed to improve the performance in H.264/AVC. The proposed architecture is an integrated architecture that combined parallel inverse transform architecture and parallel inverse quantization architecture with common operation units applied new inverse quantization equations. The equations without division operation can reduce execution time and quantity of operation for inverse quantization process. The common operation unit uses multiplier and left shifter for the equations. The inverse quantization architecture with four common operation units can reduce execution cycle of inverse quantization to one cycle. The inverse transform architecture consists of eight inverse transform operation units. Therefore, the architecture can reduce the execution cycle of inverse transform to one cycle. Because inverse quantization operation and inverse transform operation are concurrency, the execution cycle of inverse transform and inverse quantization operation for one $4{\times}4$ block is one cycle. The proposed architecture is synthesized using Magnachip 0.18um CMOS technology. The gate count and the critical path delay of the architecture are 21.9k and 5.5ns, respectively. The throughput of the architecture can achieve 2.89Gpixels/sec at the maximum clock frequency of 181MHz. As the result of measuring the performance of the proposed architecture using the extracted data from JM 9.4, the execution cycle of the proposed architecture is about 88.5% less than that of the existing designs.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.45 no.3
• /
• pp.80-92
• /
• 2008

Many predominant video coding tools in terms of coding efficiency were adopted in the latest video coding standard, H.264/AVC. Regardless of development of these predominant video coding tools such as the variable block-size motion estimation/compensation, intra prediction based on various directions, and so on, the discrete cosine transform has been continuously used starting from the early video coding standards. Generally, the correlation coefficient of the residual signal is usually less than 0.5 when this residual signal is actually encoded. In this interval of correlation coefficient, the discrete cosine transform does not show the optimal coding gain, and the discrete sine transform which is a sub-optimal transform when the correlation coefficient is in the interval from -0.5 to 0.5 can be used in conjunction with the discrete cosine transform in the video coding. In this paper, an alternative transform that alternatively uses the discrete sine transform and integer cosine transform in H.264/AVC by using rate-distortion optimization is proposed. The proposed method achieves a BD-PSNR gain of up to 0.71 dB compared to H.264/AVC JM 10.2 at relatively high bitrates.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.19 no.4
• /
• pp.325-332
• /
• 1999

A manure management plan is important for all dairy operations. This experiment was conducted to determine the effect of different nitrogen(N) application rates of liquid cattle manure on the forage quality, N recovery, and total forage yields of corn-oats cropping system and soil properties at the National Livestock Research Institute, RDA, Suweon in 1997. Eight treatments consisting of no fertilizer, chemical fertilizer $320kg\;N\;ha^{-1}$ as urea, the continuous applications of 320, 640 and $960kg\;N\;ha^{-1}$ as liquid cattle manure(LCM), the residual effects of 200, 400 and $600kg\;N\;ha^{-1}$ as liquid cattle manure were arranged in a randomized complete block design with three replications. Mean plant height of fall sown oats was 70 and 61cm at the continuous application and the residual effect plots, respectively. Mean dry matter percent of fall sown oats at the residual effect plots was higher by 0.9% than that of oats at the continuous application plots, but there were no differences among all treatments. Mean crude protein(CP), acid detergent fiber(ADF), and neutral detergent fiber (NDF) contents of fall sown oats at the continuous application plots were higher by 1.0, 1.6, and 3.1%, respectively, than those of the residual effect plots. Also, there were significant differences among treatments (P<0.05). Total forage dry matter yields of corn and oats cropping system were ranged from 11,365 to $25,668kg\;ha^{-1}$ among the treatments. The yield was orderly ranked as LCM $960kg\;N\;ha^{-1}$ > LCM $600kg\;N\;ha^{-1}$ > LCM $640kg\;N\;ha^{-1}$ > LCM $400kg\;N\;ha^{-1}$ (P<0.05). Compared with the control, manurial value(MV) was 158 and 139% for the plot of the LCM $960kg\;N\;ha^{-1}$ and that of the LCM $600kg\;N\;ha^{-1}$, respectively. N recovery percent of fall sown oats was the highest at the plot of the LCM $200kg\;N\;ha^{-1}$ by 50%, and then was higher in order of the LCM $400kg\;N\;ha^{-1}$, LCM $600kg\;N\;ha^{-1}$, and LCM $320kg\;N\;ha^{-1}$. Contents of exchangeable cation in the soil of the residual effect plots was higher than that of the continuous application plots. These results suggest that the LCM $600kg\;N\;ha^{-1}$ may be the most effective in total forage dry matter yields, manurial value, N recovery, and utilizing liquid manure N under the corn and oats double cropping system.

• Journal of Chest Surgery
• /
• v.23 no.1
• /
• pp.192-200
• /
• 1990

The results of conventional operative resection of diffuse subaortic stenosis[tunnel subaortic stenosis] have been less than satisfactory. We have performed modified Konno operation to enlarge the outflow tract of both ventricle with a patch in three patients with diffuse tunnel subaortic stenosis in the department of Thoracic and Cardiovascular Surgery, Seoul National University Children`s Hospital. Preoperative left ventricular aortic pressure gradients were 135 mmHg, 50 mmHg, 80 mmHg respectively in these patients. After right ventriculotomy, the septotomy was done and extended beyond the limit of the stenosis and fibrous and/or muscular tissue was removed from each edge of septal incision. After adequate widening of the tunnel subaortic stenosis with various patches, right ventricle was closed primarily or with prosthetic patches successfully. One patient who was diagnosed as complete atrioventricular septal defect had complete AV block preoperatively and was implanted permanent pacemaker, and others who were sinus rhythm preoperatively have no serious postoperative rhythm disturbance. One patient developed mild postoperative aortic insufficiency and one who had preoperative aortic insufficiency has still same grade of aortic insufficiency after operation. All had good postoperative hemodynamics without any postoperative residual pressure gradient.

• Transactions of the Korean Society of Mechanical Engineers
• /
• v.9 no.6
• /
• pp.691-698
• /
• 1985

This paper presents a method for the identification of vibration sources in a multiple input system where the input source may be coherent with each other. Using multi-dimensional spectral analysis, it is found that one of the most significant vibration sources of a gasoline engine is the pressure variation within the cylinder. In this analysis the concepts of residual spectral analysis and the partial coherence function are applied. Finally, the overall levels of the acceleration on the cylinder block obtained by multi-dimensional spectral analysis are compared with those by the frequency response function approach. The experimental results have shown a good agreement with the results calculated by this method the input sources are coherent strongly each other.

• Journal of Korean Neurosurgical Society
• /
• v.48 no.3
• /
• pp.281-284
• /
• 2010

Spinal epidural hematoma is a rare complication associated with pain control procedures such as facet block, acupuncture, epidural injection, etc. Although it is an uncommon cause of acute myelopathy, and it may require surgical evacuation. We report four patients with epidural hematoma developed after pain control procedures. Two procedures were facet joint blocks and the others were epidural blocks. Pain was the predominant initial symptom in these patients while two patients presented with post-procedural neurological deficits. Surgical evacuation of the hematoma was performed in two patients while in remaining two patients, surgery was initially recommended but not performed since symptoms were progressively improved. Three patients showed near complete recovery except for one patient who recovered with residual deficits. Although, spinal epidural hematoma is a rare condition, it can lead to serious complications like spinal cord compression. Therefore, it is important to be cautious while performing spinal pain control procedure to avoid such complications. Surgical treatment is an effective option to resolve the spinal epidural hematoma.

• Journal of the Korean Institute of Telematics and Electronics S
• /
• v.34S no.1
• /
• pp.80-93
• /
• 1997

This paper proposes a new technique of optimal codebook design in multistage gain-shape vector quantization (MS-GS VQ) for wireless image communication. An original image is divided into a smany blocks as possible in order to get strong robustness to channel transmission errors: the original image is decomposed into a number of subband images, each of which contains a sperate spatial frequency information and is obtained by the biorthogonal wavlet transform; each subband is separated into several consecutive VQ stages, where each stage has a residual information of the previous stage; one vector in each stage is divided into two components-gain and shape. But, this decomposition genrates too many blocks and it thus makes the determination of optimal codebooks difficult. We overcome this difficulty by evolving each block's codebook independently with different genetic algorithm that uses each stage's individual training vectors. Th eimpact of th eproposed VQ technique on the channel transmission errors is compared with that of other VQ techniques. Simulation results show that the proposed VQ technique (MS-GS VQ) with the optimal codebook designe dy genetic algorithms is very robust to channel transmission errors even under the bursty and high BER conditions.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.24 no.5 s.176
• /
• pp.1215-1230
• /
• 2000

Parallel Approaches using Cray T3E which is NIPP (Massively Parallel Processors) machine are presented for the efficient computation of the finite element analysis of 3-D shape rolling processes. D omain decomposition method coupled with parallel linear equation solver is used. Domain decomposition is applied for obtaining element tangent stifffiess matrices and residual vectors. Direct and iterative parallel algorithms are used for solving the linear equations. Direct algorithm is_parallel version of direct banded matrix solver. For iterative algorithms, the well-known preconditioned conjugate gradient solver with Jacobi preconditioner is also employed. Moreover a new effective iterative scheme with block inverse matrix preconditioner, which is named by present authors, is presented and its results are compared with the one using Jacobi preconditioner. PVM and MPI are used for message passing and synchronization between processors. The performance and efficiency of each algorithm is discussed and comparisons are made among different algorithms.