• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.24 no.8B
• /
• pp.1506-1517
• /
• 1999

In this paper, we propose two fast block matching algorithm using the distribution of mean absolute difference (MAD) at the search region overlapped with neighbor blocks and pixel subsapmling. The proposed methods use the lower and upper bound of MAD at the overlapped search region which is calculated from the MAD of neighbor block at that search position and MAD between the current block and neighbor block. In the first algorithm, we can reduce the computational complexity by executing the block matching operation at the only necessary search points. That points are selected using the lower bound of MAD. In the second algorithm, we use the statictical distribution of actual MAD which exists between the lower bound and upper bound of MAD. By using the statistical distribution of actual MAD, we can significantly reduce the computational complexity for motion estimation. after striking space key 2 times.

• Biomolecules & Therapeutics
• /
• v.31 no.3
• /
• pp.340-349
• /
• 2023

Mad2B (Mad2L2), the human homolog of the yeast Rev7 protein, is a regulatory subunit of DNA polymerase ζ that shares sequence similarity with the mitotic checkpoint protein Mad2A. Previous studies on Mad2B have concluded that it is a mitotic checkpoint protein that functions by inhibiting the anaphase-promoting complex/cyclosome (APC/C). Here, we demonstrate that Mad2B is activated in response to cisplatin-induced DNA damage. Mad2B co-localizes at nuclear foci with DNA damage markers, such as proliferating cell nuclear antigen and gamma histone H2AX (γ-H2AX), following cisplatin-induced DNA damage. However, unlike Mad2A, the binding of Mad2B to Cdc20 does not inhibit the activity of APC/C in vitro. In contrast to Mad2A, Mad2B does not localize to kinetochores or binds to Cdc20 in spindle assembly checkpoint-activated cells. Loss of the Mad2B protein leads to damaged nuclei following cisplatin-induced DNA damage. Mad2B/Rev7 depletion causes the accumulation of damaged nuclei, thereby accelerating apoptosis in human cancer cells in response to cisplatin-induced DNA damage. Therefore, our results suggest that Mad2B may be a critical modulator of DNA damage response.

• Journal of Microbiology and Biotechnology
• /
• v.15 no.4
• /
• pp.694-700
• /
• 2005

Defects in the mitotic spindle or in the attachment of chromosomes to the spindle are believed to release an activated form of spindle checkpoint complex that inhibits APC-dependent ubiquitination and subsequently arrests the cell cycle at metaphase. When the spindle assembly is disrupted, the fission yeast mitotic arrest deficient (mad) mutants fail to arrest and rapidly lose viability. To enhance our understanding of the molecular mechanisms for the pathway of checkpoint function, the functional characterizations of Mad 1 p from Schizosaccharomyces pombe involved in this process have been carried out. Yeast two-hybrid and various deletion analyses of S. pombe Mad1 p reveal that the C terminus of Mad1p is critical for the binding of Mad2p and maintenance of Mad 1 p-Mad2p interaction. In addition, it was found. that the Mad1p region (residues 206-356) is essential for Mad1p-other checkpoint components. Mad1p truncating this region is sufficient to bind Mad2p but abolishes the checkpoint function, indicating that the checkpoint function is necessary for interaction of Mad 1 p-other checkpoint components. The possible functions of S. pombe Mad1p at the cell cycle checkpoint are discussed.

• Proceedings of the KIEE Conference
• /
• 2007.10a
• /
• pp.441-442
• /
• 2007

본 논문은 H.264 MB Layer 비트율 제어를 위한 적응적인 MAD 예측 방법을 제안한다. 첫째, 공간 인접 MB 들 간의 유사도를 기반으로 공간예측 MAD를 구하고 둘째, 프레임의 픽셀 평균값의 차이로 장면 전환을 검출한다. 셋째, 공간예측 MAD와 시간예측 MAD에 MB의 예측 움직임 벡터를 이용한 가중치를 주어 적응적으로 MAD를 예측한다. 실험 결과를 통해 제안한 MAD 예측 방법이 JM11.0의 방법보다 더욱 우수한 예측 성능을 보임을 살펴본다.

• The Korean Journal of Physiology and Pharmacology
• /
• v.27 no.5
• /
• pp.427-436
• /
• 2023

Mitotic arrest deficient 2 like 2 (Mad2L2, also known as Mad2B), the human homologue of the yeast Rev7 protein, is a regulatory subunit of DNA polymerase ζ that shares high sequence homology with Mad2, the mitotic checkpoint protein. Previously, we demonstrated the involvement of Mad2B in the cisplatin-induced DNA damage response. In this study, we extend our findings to show that Mad2B is recruited to sites of DNA damage in human cancer cells in response to cisplatin treatment. We found that in undamaged cells, Mad2B exists in a complex with Polζ-Rev1 and the APC/C subunit Cdc27. Following cisplatin-induced DNA damage, we observed an increase in the recruitment of Mad2B and Cdc20 (the activators of the APC/C), to the complex. The involvement of Mad2B-Cdc20-APC/C during DNA damage has not been reported before and suggests that the APC/C is activated following cisplatin-induced DNA damage. Using an in vitro ubiquitination assay, our data confirmed Mad2B-dependent activation of APC/C in cisplatin-treated cells. Mad2B may act as an accelerator for APC/C activation during DNA damage response. Our data strongly suggest a role for Mad2B-APC/C-Cdc20 in the ubiquitination of proteins involved in the DNA damage response.

• Journal of the Korean Institute of Telematics and Electronics S
• /
• v.36S no.5
• /
• pp.48-55
• /
• 1999

본 논문에서는 움직임 추정시 인접된 블록간의 탐색 영역이 중첩됨을 이용하여 전역 탐색 기법과 동일한 성능을 유지하면서 계산량을 현저히 감소시킬수 있는 고속 움직임 추정 기법을 제안하였다. 제안한 기법에서는 현재 움직임 추정을 행하고자 하는 블록에 대한 탐색점 중에서 인접된 블록과 중첩되는 탐색점에 대하여는 먼저 평균 절대 오차 (mean absoulte difference; MAD)를 계산할 필요가 있을지에 대한 판별을 행한 뒤 MAD 계산이 필요한 경우에 대하여서만 MAD를 구한다. MAD 계산 여부에 대한 판별에는 현재 블록과 인접 블록간의 MAD 와 인접 블록의 각 탐색점에 대한 MAD를 이용한다. 여기에 사용된 현재 블록과 인접 블록간의 MAD는 각 블록에 대하여 한번만 계산하면 되고, 인접 블록의 각 탐색점에 대한 MAD는 이미 구해져 있기 때문에 한번의 MAD 계산을 추가함으로써 탐색점 수를 현저히 감소시킬 수 있었다. 컴퓨터 모의 실험 결과로부터 제안한 방법이 전역 탐색 알고리즘과 동일한 성능을 유지하면서 많은 계산량의 감소를 얻을 수 있음을 확인 할 수 있었다.

• Journal of Korea Multimedia Society
• /
• v.4 no.5
• /
• pp.406-413
• /
• 2001

Ordinary high-speed block matching algorithms have a disadvantage that they need to get MAD (Mean Absolute Distance) as many as the number of search points due to comparing the MAD between the current frame's search block and the reference frame's search block. To solve such disadvantage of high-speed block matching algorithm, the proposed high-speed DS algorithm employs a MMAD calculation method using a specific characteristic that neighboring pixels have almost same values. In this thesis, we can get rid of unnecessary MAD calculation between the search point block by the new calculation method which uses the previously calculated MAD as the current search point and by breaking from the established MAD calculation method which calculates the MAD of a new search point by each search stage. Comparing with the established high-speed block matching algorithm, this new calculation's estimated movement error was shown as similar, and th total calculation amount decreased by $2FN^2Ep$.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.24 no.9B
• /
• pp.1697-1703
• /
• 1999

In this paper, we propose the fast block matching algorithm with half pel accuracy using the lower bound of mean absolute difference (MAD) at search point of half pel accuracy motion estimation. The proposed method uses the lower bound of MAD at search point of half pel accuracy which calculated from MAD's at search points of integer pel accuracy. We can reduce the computational complexity by executing the block matching operation only at the necessary search point. The points are selected when the lower bound of MAD at that point is smaller than reference MAD of integer pel motion estimation. Experimental results show that the proposed method can reduce the computational complexity considerably and keeping the same performance with conventional method.

• Journal of the korean veterinary medical association
• /
• v.34 no.8
• /
• pp.544-546
• /
• 1998

• Applied Chemistry for Engineering
• /
• v.27 no.5
• /
• pp.532-536
• /
• 2016

In this study, single-stage continuous anaerobic reactors to treat sewage sludge were operated under different temperature (55 and $35^{\circ}C$; $R_{TAD}$ and $R_{MAD}$) to evaluate the reactor stability and performance of the thermophilic and mesophilic anaerobic digestion. During the overall digestion, both anaerobic reactors maintained quite stable and constant pH and total alkalinity (TA) values in the range of 6.5-8.0 and 3-4 g $CaCO_3/L$, respectively. After the start-up period, $R_{TAD}$ showed 10% higher VS removal efficiency than that of $R_{MAD}$ ($R_{TAD}$; 43.3%; $R_{MAD}$ : 33.6%). Although organic acids such as acetic and propionic acid were detected in both anaerobic reactors at the start-up period, all organic acids in $R_{TAD}$ and $R_{MAD}$ were consumed at the steady state condition. Also $R_{TAD}$ showed 31.4 % higher methane production rate (MPR) than that of $R_{MAD}$ at the steady state condition ($R_{TAD}$; 243 mL $CH_4/L/d$; $R_{MAD}$ : 185 mL $CH_4/L/d$). Meanwhile, the experimental results indicated similar methane yield between $R_{TAD}$ and $R_{MAD}$.