• Title/Summary/Keyword: raptor

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Effective identification of dominant fully absorbing sets for Raptor-like LDPC codes

  • Woncheol Cho;Chanho Yoon;Kapseok Chang;Young-Jo Ko
    • ETRI Journal
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    • v.45 no.1
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    • pp.7-17
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    • 2023
  • The error-rate floor of low-density parity-check (LDPC) codes is attributed to the trapping sets of their Tanner graphs. Among them, fully absorbing sets dominantly affect the error-rate performance, especially for short blocklengths. Efficient methods to identify the dominant trapping sets of LDPC codes were thoroughly researched as exhaustively searching them is NP-hard. However, the existing methods are ineffective for Raptor-like LDPC codes, which have many types of trapping sets. An effective method to identify dominant fully absorbing sets of Raptor-like LDPC codes is proposed. The search space of the proposed algorithm is optimized into the Tanner subgraphs of the codes to afford time-efficiency and search-effectiveness. For 5G New Radio (NR) base graph (BG) 2 LDPC codes for short blocklengths, the proposed algorithm finds more dominant fully absorbing sets within one seventh of the computation time of the existing search algorithm, and its search-effectiveness is verified using importance sampling. The proposed method is also applied to 5G NR BG1 LDPC code and Advanced Television Systems Committee 3.0 type A LDPC code for large blocklengths.

On-Chip Multiprocessor with Simultaneous Multithreading

  • Park, Kyoung;Choi, Sung-Hoon;Chung, Yong-Wha;Hahn, Woo-Jong;Yoon, Suk-Han
    • ETRI Journal
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    • v.22 no.4
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    • pp.13-24
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    • 2000
  • As more transistors are integrated onto bigger die, an on-chip multiprocessor will become a promising alternative to the superscalar microprocessor that dominates today's microprocessor marketplace. This paper describes key parts of a new on-chip multiprocessor, called Raptor, which is composed of four 2-way superscalar processor cores and one graphic co-processor. To obtain performance characteristics of Raptor, a program-driven simulator and its programming environment were developed. The simulation results showed that Raptor can exploit thread level parallelism effectively and offer a promising architecture for future on-chip multi-processor designs.

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Raptor FEC Based Channel-Adaptive Video Transmission Scheme over WiBro Network (와이브로 환경에서 랩터 FEC 기반의 채널 적응형 비디오 전송 기법)

  • Kim, Hye-Soo;Jeong, Jae-Yun;Byun, Keun-Yung;Nam, Hyeong-Min;Ko, Sung-Jea
    • Journal of IKEEE
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    • v.13 no.4
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    • pp.29-36
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    • 2009
  • The packet loss and the disconnection during handoff are the most critical problems which degrade the video quality in wireless video streaming. To cope with these problems, we propose an efficient video streaming method in this paper, which does not only dynamically adjust the video transmission rate based on the raptor forward error correction (FEC) level, but also minimize the error propagation during handoff. Firstly, the channel bandwidth of the wireless broadband internet, called WiBro, is estimated by analyzing channel parameters including the carrier to interference and noise ratio (CINR) and the handoff. Secondly, the streaming server adjusts the next transmission rate according to the estimated channel bandwidth and the raptor FEC level to avoid packet error. Also, the encoder performs the intra refresh method that inserts an intra frame (I-frame) right after handoff to reduce the error propagation effectively. Experimental results indicate that the proposed method can improve the performance of the video streaming over WiBro network.

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Effects on hematology and blood biochemistry profile of intramuscular meloxicam injection in Brahminy kite and Barn owl

  • Ratiwan Sitdhibutr;Raveewan Ploypan;Sirawit Subaneg;Chaiyan Kasorndorkbua
    • Journal of Veterinary Science
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    • v.24 no.3
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    • pp.43.1-43.8
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    • 2023
  • Background: Meloxicam is used widely for exotic animal analgesia, but its toxicity in common raptor species in Thailand is unclear. Objectives: This study evaluated the single-dose effect of intramuscular meloxicam in common raptor species in Thailand for short-term and long-term periods. Methods: Twenty-two raptors were administered a single 1 mg/kg dose of meloxicam individually via intramuscular injection. The following were evaluated: clinical appearance, body weight, body condition score, body temperature, fecal appearance, complete blood cell count, and biochemistry panel before (day 0) and after the injection (1, 7, and 30 days). The collected samples were categorized into three groups: Brahminy kite (Haliastur indus) (n = 10), adult Barn owl (Tyto javanica) (n = 4), and juvenile Barn owl (n = 8). Results: None of the raptors in the study groups showed any abnormalities. The hematological profiles were significantly different in the short-term period (day 1 and day 7). The creatinine, aspartate aminotransferase, and creatinine kinase increased in several groups. On the other hand, the packed cell volume decreased in the Brahminy kite and juvenile Barn owl groups. According to the findings, an intramuscular injection of 1 mg/kg meloxicam affected the blood biochemistry panel of the muscle, but the affected raptors recovered within one week. Conclusions: An intramuscular injection of meloxicam at a single 1 mg/kg dose in Brahminy kites and Barn owls was not associated with the morbidity, hepatotoxicity, gastrointestinal toxicity, and nephrotoxicity in the short- and long-term periods.

An Automated Fiber-optic Biosensor Based Binding Inhibition Assay for the Detection of Listeria Monocytogenes

  • Kim, Gi-Young;Morgan, Mark;Ess, Daniel;Hahm, Byoung-Kwon;Kothapalli, Aparna;Bhunia, Arun
    • Food Science and Biotechnology
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    • v.16 no.3
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    • pp.337-342
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    • 2007
  • Conventional methods for pathogen detection and identification are labor-intensive and take days to complete. Biosensors have shown great potential for the rapid detection of foodborne pathogens. Fiber-optic biosensors have been used to rapidly detect pathogens because they can be very sensitive and are simple to operate. However, many fiber-optic biosensors rely on manual sensor handling and the sandwich assay, which require more effort and are less sensitive. To increase the simplicity of operation and detection sensitivity, a binding inhibition assay method for detecting Listeria monocytogenes in food samples was developed using an automated, fiber-optic-based immunosensor: RAPTOR (Research International, Monroe, WA, USA). For the assay, fiber-optic biosensors were developed by the immobilization of Listeria antibodies on polystyrene fiber waveguides through a biotin-avidin reaction. Developed fiber-optic biosensors were incorporated into the RAPTOR to evaluate the detection of L. monocytogenes in frankfurter samples. The binding inhibition method combined with RAPTOR was sensitive enough to detect L. monocytogenes ($5.4{\times}10^7\;CFU/mL$) in a frankfurter sample.