• Title/Summary/Keyword: early termination

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Modified 3-step Search Motion Estimation Algorithm for Effective Early Termination (효과적인 조기 중단 기법을 위한 변형된 3단계 탐색 움직임 추정 알고리즘)

  • Yang, Hyeon-Cheol;Lee, Seong-Soo
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.47 no.7
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    • pp.70-77
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    • 2010
  • Motion estimation occupies most of the required computation in video compression, and many fast search algorithms were propsoed to reduce huge computation. SAD (sum-of-absolute difference) calculation is the most computation-intensive process in the motion estimation. Early termination is widely used in SAD calculation, where SAD calculation is terminated and it proceeds to next search position if partial SAD during SAD calculation exceeds current minimum SAD. In this paper, we proposed a modified 3-step search algorithm for effective early termination where only search order of search positions are adaptive rearranged. Simulation results show that the proposed motion estimation algorithm reduces computation by 17~30% over conventional 3-step search algorithm without extra computation, while maintaining same performance.

Fast Intermode Decision for Scalable Video Coding using Statistical Hypothesis Testing (스케일러블 비디오 부호화에서 통계적 가설 검증 기법을 이용한 고속 화면간 모드 결정)

  • Lee, Bum-Shik;Hahm, Sang-Jin;Kim, Byung-Sun;Lee, Keun-Sik;Park, Keun-Soo;Kim, Mun-Churl
    • Journal of Broadcast Engineering
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    • v.12 no.3
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    • pp.250-265
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    • 2007
  • In this paper, a fast intermode decision scheme is introduced by efficiently performing the mode decision using statistical hypothesis testing for hierarchical B-picture coding of SVC, in which much computational power is expensed for combined variable block sizes and hierarchical B-pictures. The hypothesis testing in the proposed method is performed on $16{\times}16\;and\;8{\times}8$ blocks to have early termination for RD computation of all possible modes. The early termination in intermode decision is performed by comparing the pixel values of current blocks and corresponding motion-compensated blocks. The proposed scheme exhibits effective early termination behavior in intermode decision and leads to a significant reduction up to 69% in computational complexity with slight increment in bit amounts. The degradation of visual quality turns out to be negligible in terms of PSNR values.

Characteristics of Initiation and Termination of Muscle Contraction in Early Hemiparetic Wrists: Analysis of Median Frequency (초기 편마비 환자에서 손목 근수축 개시 및 종료의 특성: 중앙주파수 분석)

  • Chung, Yi-Jung;Cho, Sang-Hyun;Kwon, Oh-Yun;Lee, Young-Hee
    • Physical Therapy Korea
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    • v.13 no.1
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    • pp.38-46
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    • 2006
  • The purposes of this study were to investigate the median frequency (MDF) between initiation and termination of muscle contraction through surface electromyographic (sEMG) analysis and to propose the basis of clinical treatment for movement problems in early hemiparetic upper limbs. Thirteen patients who had stroke with onset less than 3 months prior to the study and seven control subjects participated in the study. The median frequency in initiation and termination of muscle contraction was recorded from wrist flexor and extensor muscles using the sEMG, with 3 second beeper signals, during maximal isometric wrist flexion and extension. Flexion and extension must be done as quickly and forcefully as possible. The results of the study were as follows: 1. The MDF of the onset and offset sections were significantly lower on the paretic than the nonparetic and control sides. 2. The MDF of the offset section significantly decreased on the paretic and nonparetic sides. Consequently, this study showed that the lowering of the MDF was due to the hemiparetic wrist motor impairment and muscle weakness. These results are also related to Fugl-Meyer motor assessment (FMA) scores in hemiparetic upper limbs. This study also suggests that since muscle weakness of early stroke patients affects the functional decrease of upper limbs, further studies must focus on the treatment to improve muscle agility and muscle fiber recruitment efficiency that can induce the functional recovery correlated to motor control.

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Biochemical Changes during Embryonic Diapause in Domestic Silkworm, Bombyx mori L. (Lepidoptera: Bombycidae)

  • Singh, Tribhuwan;Saratchandra, Beera
    • International Journal of Industrial Entomology and Biomaterials
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    • v.5 no.1
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    • pp.1-12
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    • 2002
  • Ecophysiologically diapause represents a syndrome of physiological and biochemical characteristics, all of which ensure survival during a long period of dormancy. Since, silkworm enters diapause as embryo at the early embryonic stage, the duration of egg life depends on the duration of embryonic diapause. The nature of diapause in silkworm, Bombyx mori, is primarily determined by genetic characters and endocrinologicnl mechanisms, mediated by environmental factors such as temperature and photoperiod. Hibernating potency value besides nucleic acid and carbohydrate metabolism, production and utilization of sorbitol are also equally responsible for induction, initiation, determination, maintenance and termination of diapause. Embryonic diapause in Bombyx moir, induced by active secretion of sub-oesophageal ganglion is attributed to hormonal system and metabolic adjustment, which serves to bring about a new physiological state. Metabolic conversion of trehalose to glycogen at induction, glycogen to sorbitol at initiation and sorbitol to glycogen at termination of diapause is correlated and in each metabolic shift a key enzyme becomes active in response to hormonal and environmental stimulation. An attempt has been made in this review article to discuss briefly the nature of embryonic diapause, influence of various factors on diapause nature, hormonal mechanism of diapause besides biochemical composition of egg, nucleic acid and carbohydrate metabolism, production and utilization of sorbitol in relation to induction, determination, maintenance, initiation and termination of diapause in the silkworm, Bombyx mori.

A Fast and Accurate Face Tracking Scheme by using Depth Information in Addition to Texture Information

  • Kim, Dong-Wook;Kim, Woo-Youl;Yoo, Jisang;Seo, Young-Ho
    • Journal of Electrical Engineering and Technology
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    • v.9 no.2
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    • pp.707-720
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    • 2014
  • This paper proposes a face tracking scheme that is a combination of a face detection algorithm and a face tracking algorithm. The proposed face detection algorithm basically uses the Adaboost algorithm, but the amount of search area is dramatically reduced, by using skin color and motion information in the depth map. Also, we propose a face tracking algorithm that uses a template matching method with depth information only. It also includes an early termination scheme, by a spiral search for template matching, which reduces the operation time with small loss in accuracy. It also incorporates an additional simple refinement process to make the loss in accuracy smaller. When the face tracking scheme fails to track the face, it automatically goes back to the face detection scheme, to find a new face to track. The two schemes are experimented with some home-made test sequences, and some in public. The experimental results are compared to show that they outperform the existing methods in accuracy and speed. Also we show some trade-offs between the tracking accuracy and the execution time for broader application.

Fast CU Encoding Schemes Based on Merge Mode and Motion Estimation for HEVC Inter Prediction

  • Wu, Jinfu;Guo, Baolong;Hou, Jie;Yan, Yunyi;Jiang, Jie
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.3
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    • pp.1195-1211
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    • 2016
  • The emerging video coding standard High Efficiency Video Coding (HEVC) has shown almost 40% bit-rate reduction over the state-of-the-art Advanced Video Coding (AVC) standard but at about 40% computational complexity overhead. The main reason for HEVC computational complexity is the inter prediction that accounts for 60%-70% of the whole encoding time. In this paper, we propose several fast coding unit (CU) encoding schemes based on the Merge mode and motion estimation information to reduce the computational complexity caused by the HEVC inter prediction. Firstly, an early Merge mode decision method based on motion estimation (EMD) is proposed for each CU size. Then, a Merge mode based early termination method (MET) is developed to determine the CU size at an early stage. To provide a better balance between computational complexity and coding efficiency, several fast CU encoding schemes are surveyed according to the rate-distortion-complexity characteristics of EMD and MET methods as a function of CU sizes. These fast CU encoding schemes can be seamlessly incorporated in the existing control structures of the HEVC encoder without limiting its potential parallelization and hardware acceleration. Experimental results demonstrate that the proposed schemes achieve 19%-46% computational complexity reduction over the HEVC test model reference software, HM 16.4, at a cost of 0.2%-2.4% bit-rate increases under the random access coding configuration. The respective values under the low-delay B coding configuration are 17%-43% and 0.1%-1.2%.

Analyses of alternative polyadenylation: from old school biochemistry to high-throughput technologies

  • Yeh, Hsin-Sung;Zhang, Wei;Yong, Jeongsik
    • BMB Reports
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    • v.50 no.4
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    • pp.201-207
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    • 2017
  • Alternations in usage of polyadenylation sites during transcription termination yield transcript isoforms from a gene. Recent findings of transcriptome-wide alternative polyadenylation (APA) as a molecular response to changes in biology position APA not only as a molecular event of early transcriptional termination but also as a cellular regulatory step affecting various biological pathways. With the development of high-throughput profiling technologies at a single nucleotide level and their applications targeted to the 3'-end of mRNAs, dynamics in the landscape of mRNA 3'-end is measureable at a global scale. In this review, methods and technologies that have been adopted to study APA events are discussed. In addition, various bioinformatics algorithms for APA isoform analysis using publicly available RNA-seq datasets are introduced.

Genetic Factors Affecting Insecticidal Crystal Protein Synthesis in Bacillus thuringiensis

  • Park, Hyung-Woo;Brian A. Federici
    • International Journal of Industrial Entomology and Biomaterials
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    • v.1 no.1
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    • pp.1-7
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    • 2000
  • Early studies of the molecular biology of Bacillus thuringeinsis suggested that genetic manipulation of this species could create combinations of genes more useful than those known to occur in natural isolates. Breakthroughs that made these manipulations possible include the cloning of many genes encoding endotoxins, the development of transformation vectors, and various PCR techniques. This paper reviews several genetic factors such as promoters, a 5'mRNA stabilizing sequence, 3'transcription termination sequences, and helper proteins that have been used to enhance crystal protein synthesis, and shows how these genetic elements can be manipulated with new molecular tools to develop more efficacious strains of B. thuringiensis.

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Early Termination Algorithm of Merge Mode Search for Fast High Efficiency Video Coding (HEVC) Encoder (HEVC 인코더 고속화를 위한 병합 검색 조기 종료 결정 알고리즘)

  • Park, Chan Seob;Kim, Byung Gyu;Jun, Dong San;Jung, Soon Heung;Kim, Youn Hee;Seok, Jin Wook;Choi, Jin Soo
    • Journal of Broadcast Engineering
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    • v.18 no.5
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    • pp.691-701
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    • 2013
  • In this paper, an early termination algorithm for merge process is proposed to reduce the computational complexity in High Efficiency Video Coding (HEVC) encoder. In the HEVC, the same candidate modes from merge candidate list (MCL) are shared to predict a merge or merge SKIP mode. This search process is performed by the number of the obtained candidates for the both of the merge and SKIP modes. This may cause some redundant search operations. To reduce this redundant search operation, we employ the neighboring blocks which have been encoded in prior, to check on the contextual information. In this study, the spatial, temporal and depth neighboring blocks have been considered to compute a correlation information. With this correlation information, an early termination algorithm for merge process is suggested. When all modes of neighboring blocks are SKIP modes, then the merge process performs only SKIP mode. Otherwise, usual merge process of HEVC is performed Through experimental results, the proposed method achieves a time-saving factor of about 21.25% on average with small loss of BD-rate, when comparing to the original HM 10.0 encoder.