• ETRI Journal
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• v.28 no.3
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• pp.329-336
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• 2006

This paper investigates the problem of protecting multicast sessions in mesh wavelength-division multiplexing (WDM) networks against single link failures, for example, a fiber cut in optical networks. First, we study the two characteristics of multicast sessions in mesh WDM networks with sparse light splitter configuration. Traditionally, a multicast tree does not contain any circles, and the first characteristic is that a multicast tree has better performance if it contains some circles. Note that a multicast tree has several branches. If a path is added between the leave nodes on different branches, the segment between them on the multicast tree is protected. Based the two characteristics, the survivable multicast sessions routing problem is formulated into an Integer Linear Programming (ILP). Then, a heuristic algorithm, named the adaptive shared segment protection (ASSP) algorithm, is proposed for multicast sessions. The ASSP algorithm need not previously identify the segments for a multicast tree. The segments are determined during the algorithm process. Comparisons are made between the ASSP and two other reported schemes, link disjoint trees (LDT) and shared disjoint paths (SDP), in terms of blocking probability and resource cost on CERNET and USNET topologies. Simulations show that the ASSP algorithm has better performance than other existing schemes.

• Journal of Communications and Networks
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• v.8 no.2
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• pp.212-219
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• 2006

In this paper, a new turbo codes-based hybrid automatic repeat request (TC-HARQ) scheme with segment selective repeat (SSR) is proposed. The main strategy is, upon retransmission, to repeat the data that are most important for the next round of decoding based on the distribution of residual errors after current decoding. The performance in terms of reliability and throughput is analyzed. To adapt to correlated fading channels where an inter-leaver is always employed before transmission, we further modify the SSR strategy so that data having experienced correlated deep fading are selected for retransmission. Finally, this proposed scheme is applied to the wideband code division multiple access (WCDMA) system under frequency selective fading channels. Simulation results demonstrate that in all single and multiple user cases, SSR-based TC-HARQ leads to significant throughput improvement with similar bit error rate (BER) performance as compared to type-I TC-HARQ.

• Journal of Microbiology and Biotechnology
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• v.4 no.4
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• pp.264-269
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• 1994

To determine the nucleotide sequence of the ds RNA segment B containing the RNA dependent RNA polymerase (RdRp) gene of the DRT strain of infectious pancreatic necrosis virus (lPNV), the cDNA of the ds RNA segment B of the DRT strain of IPNV was synthesized using the reverse transcriptase (RT)-polymerase chain reaction (PCR) and its cDNA nucleotide sequence was determined. The DRT segment B was 2, 783 bp long and contained only a single long open reading frame (ORF) of 2, 535 bp in length. This ORF nucleotides encoded the VPl protein, the putative RdRp of IPNV. The VPl protein comsisted of 845 amino acids. The molecular weight of the RdRp, as deduced from the nucleotide sequence, is 94, 426. The nucleotide sequence of the ORF of the DRT showed 89.7% homology to the Jasper strain, but 80.8% to the Sp strain. The amino acid sequence of the ORF of the DRT sho.wed 97.6% homology to the Jasper strain, but 88.7% to the Sp strain. The conserved GTP-binding motif was detected in VPl protein.

• Journal of the Korea Society of Computer and Information
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• v.13 no.6
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• pp.1-12
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• 2008

This paper presents automatic moving object detection method using the rotating camera covering larger area with a single camera. The proposed method is based on the edge segment matching which robust to the dynamic environment with illumination change and background movement. The proposed algorithm presents an edge segment based background panorama image generation method minimizing the distortion due to image stitching, the background image generation method using Generalized Hough Transformation which can reliably register the current image to the panorama image overcoming the stitching distortions, the moving edge segment extraction method that overcome viewpoint difference and distortion. The experimental results show that the proposed method can detect correctly moving object under illumination change and camera vibration.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.7
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• pp.2589-2609
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• 2021

Segment routing (SR) is a highly implementable approach for traffic engineering (TE) with high flexibility, high scalability, and high stability, which can be established upon existing network infrastructure. Thus, when a network failure occurs, it can leverage the existing rerouting methods, such as rerouting based on Interior Gateway Protocol (IGP) and fast rerouting with loop-free alternates. To better exploit these features, we propose a high-performance and easy-to-deploy method SRUF (Segment Routing under Uncertain Failures). The method is inspired by the Value-at-Risk (VaR) theory in finance. Just as each investment risk is considered in financial investment, SRUF also considers each traffic distribution scheme's risk when forwarding traffic to achieve optimal traffic distribution. Specifically, SRUF takes into account that every link may fail and therefore has inherent robustness and high availability. Also, SRUF considers that a single link failure is a low-probability event; hence it can achieve high performance. We perform experiments on real topologies to validate the flexibility, high-availability, and load balancing of SRUF. The results show that when given an availability requirement, SRUF has greater load balancing performance under uncertain failures and that when given a demand requirement, SRUF can achieve higher availability.

• Animal Systematics, Evolution and Diversity
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• v.39 no.4
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• pp.176-211
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• 2023

Nine copepod species of the family Artotrogidae Brady, 1880 are described or redescribed from Korea. Included new species are two in the genus Artotrogus Boeck, 1859, one each in the genera Bradypontius Giesbrecht, 1895, Cryptopontius Giesbrecht, 1899, Neopontius Scott T., 1898 and Chejupontius n. gen., and two in the genus Sewellopontius Ummerkutty, 1966. Chejupontius n. gen. resembles Ascidipontius Kim I. H., 1996, Pulicitrogus Kim I. H., 1998, and Sewellopontius in having reduced armature of leg 1, but is distinguished from these and other genera of the family by the large, mediodistally expanded protopod of leg 5 and by a combination of characters exhibited in leg 1 that the first exopodal segment lacks an inner seta, the second exopodal segment lacks an outer spine, the third exopodal segment is armed with three spines plus one to three setae, and the second endopodal segment is armed with a single inner seta. Pteropontius cristatus Giesbrecht, 1895 known previously only from the Mediterranean Sea is redescribed, based on a newly collected specimen from Korea, and P. trimerus Kim I. H., 1996 is removed to the genus Sewellopontius. A short note is given for the epibiotic suctorian Thecacineta calix (Schroder, 1907) which was found attached to the antennule of a new copepod species.

• The korean journal of orthodontics
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• v.45 no.1
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• pp.20-28
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• 2015

Objective: The purpose of this study was to observe stress distribution and displacement patterns of the entire maxillary arch with regard to distalizing force vectors applied from interdental miniscrews. Methods: A standard three-dimensional finite element model was constructed to simulate the maxillary teeth, periodontal ligament, and alveolar process. The displacement of each tooth was calculated on x, y, and z axes, and the von Mises stress distribution was visualized using color-coded scales. Results: A single distalizing force at the archwire level induced lingual inclination of the anterior segment, and slight intrusive distal tipping of the posterior segment. In contrast, force at the high level of the retraction hook resulted in lingual root movement of the anterior segment, and extrusive distal translation of the posterior segment. As the force application point was located posteriorly along the archwire, the likelihood of extrusive lingual inclination of the anterior segment increased, and the vertical component of the force led to intrusion and buccal tipping of the posterior segment. Rotation of the occlusal plane was dependent on the relationship between the line of force and the possible center of resistance of the entire arch. Conclusions: Displacement of the entire arch may be dictated by a direct relationship between the center of resistance of the whole arch and the line of action generated between the miniscrews and force application points at the archwire, which makes the total arch movement highly predictable.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.8 s.338
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• pp.15-26
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• 2005

In this paper, we propose an efficient $GF(2^m)$ multi-segment multiplier architecture and study its application to elliptic curve cryptography processors. The multi-segment based ECC datapath has a very small combinational multiplier to compute partial products, most of its internal data buses are word-sized, and it has only a single m bit multiplexer and a single m bit register. Hence, the resource requirements of the proposed ECC datapath can be minimized as the segment number increases and word-size is decreased. Hence, as compared to the ECC processor based on digit-serial multiplication, the proposed ECC datapath is more efficient in resource usage. The resource requirement of ECC Processor implementation depends not only on the number of basic hardware components but also on the complexity of interconnection among them. To show the realistic area efficiency of proposed ECC processors, we implemented both the ECC processors based on the proposed multi-segment multiplication and digit serial multiplication and compared their FPGA resource usages. The experimental results show that the Proposed multi-segment multiplication method allows to implement ECC coprocessors, requiring about half of FPGA resources as compared to digit serial multiplication.

• Proceedings of the Korean Biophysical Society Conference
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• 1999.06a
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• pp.37-37
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• 1999

The influenza A viruses which are the most severe and common among the influenza viruses have 8 segmented RNA genomes Each RNA segment has highly conserved 3' and 5' terminal sequence except a single U\longrightarrowC variation especially in the 4 position of the 3' terminal of the 3 segments encoding own RNA polymerase.(omitted)

• Journal of Korean Neurosurgical Society
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• v.58 no.1
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• pp.54-59
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• 2015

Objective : The aim of this prospective study was to evaluate the efficacy of bone cement-augmented percutaneous short segment fixation for treating Kummell's disease accompanied by severe osteoporosis. Methods : From 2009 to 2013, ten patients with single-level Kummell's disease accompanied by severe osteoporosis were enrolled in this study. After postural reduction for 1-2 days, bone cement-augmented percutaneous short segment fixation was performed at one level above, one level below, and at the collapsed vertebra. Clinical results, radiological parameters, and related complications were assessed preoperatively and at 1 month and 12 months after surgery. Results : Prior to surgery, the mean pain score on the visual analogue scale was $8.5{\pm}1.5$. One month after the procedure, this score improved to $2.2{\pm}2.0$ and the improvement was maintained at 12 months after surgery. The mean preoperative vertebral height loss was $48.2{\pm}10.5%$, and the surgical procedure reduced this loss to $22.5{\pm}12.4%$. In spite of some recurrent height loss, significant improvement was achieved at 12 months after surgery compared to preoperative values. The kyphotic angle improved significantly from $22.4{\pm}4.9^{\circ}$ before the procedure to $10.1{\pm}3.8^{\circ}$ after surgery and the improved angle was maintained at 12 months after surgery despite a slight correction loss. No patient sustained adjacent fractures after bone cement-augmented percutaneous short segment fixation during the follow-up period. Asymptomatic cement leakage into the paravertebral area was observed in one patient, but no major complications were seen. Conclusion : Bone cement-augmented percutaneous short segment fixation can be an effective and safe procedure for Kummell's disease.