• Title/Summary/Keyword: recovery block

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Block Sparse Signals Recovery via Block Backtracking-Based Matching Pursuit Method

  • Qi, Rui;Zhang, Yujie;Li, Hongwei
    • Journal of Information Processing Systems
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    • v.13 no.2
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    • pp.360-369
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    • 2017
  • In this paper, a new iterative algorithm for reconstructing block sparse signals, called block backtracking-based adaptive orthogonal matching pursuit (BBAOMP) method, is proposed. Compared with existing methods, the BBAOMP method can bring some flexibility between computational complexity and reconstruction property by using the backtracking step. Another outstanding advantage of BBAOMP algorithm is that it can be done without another information of signal sparsity. Several experiments illustrate that the BBAOMP algorithm occupies certain superiority in terms of probability of exact reconstruction and running time.

A Mobile Flash File System - MJFFS (모바일 플래시 파일 시스템 - MJFFS)

  • 김영관;박현주
    • Journal of Information Technology Applications and Management
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    • v.11 no.2
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    • pp.29-43
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    • 2004
  • As the development of an information technique, gradually, mobile device is going to be miniaturized and operates at high speed. By such the requirements, the devices using a flash memory as a storage media are increasing. The flash memory consumes low power, is a small size, and has a fast access time like the main memory. But the flash memory must erase for recording and the erase cycle is limited. JFFS is a representative filesystem which reflects the characteristics of the flash memory. JFFS to be consisted of LSF structure, writes new data to the flash memory in sequential, which is not related to a file size. Mounting a filesystem or an error recovery is achieved through the sequential approach. Therefore, the mounting delay time is happened according to the file system size. This paper proposes a MJFFS to use a multi-checkpoint information to manage a mass flash file system efficiently. A MJFFS, which improves JFFS, divides a flash memory into the block for suitable to the block device, and stores file information of a checkpoint structure at fixed interval. Therefore mounting and error recovery processing reduce efficiently a number of filesystem access by collecting a smaller checkpoint information than capacity of actual files. A MJFFS will be suitable to a mobile device owing to accomplish fast mounting and error recovery using advantage of log foundation filesystem and overcoming defect of JFFS.

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An recovery algorithm and error position detection in digital circuit mimicking by self-repair on Cell (세포의 자가 치료 기능을 모사한 디지털 회로에서의 오류위치 확인 및 복구 알고리즘)

  • Kim, Seok-Hwan;Hur, Chang-Wu
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2015.10a
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    • pp.842-846
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    • 2015
  • In this study, we propose an algorithm of the method of recovering quickly find the location of the error encountered during separate operations in the functional structure of complex digital circuits by mimicking the self-healing function of the cell. By the digital circuit was divided by 9 function block unit of function, proposes a method that It can quickly detect and recover the error position. It was the detection and recovery algorithms for the error location in the digital circuit of a complicated structure and could extended the number of function block for the $3{\times}3$ matrix structure on the digital circuit.

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Key Recovery Attacks on Fantomas and Robin Using Related-Key Differentials (연관키 차분 특성을 이용한 Fantomas와 Robin의 키 복구 공격)

  • Kim, Hangi;Kim, Jongsung
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.28 no.4
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    • pp.803-807
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    • 2018
  • The Fantomas and the Robin are the block ciphers included in the LS-designs, the family of block ciphers. They are designed to efficiently apply the masking technique, which is a side-channel analysis countermeasure technique, using L-boxes and S-boxes capable of bit slice implementation. In this paper, we show that the key recovery attacks of Fantomas and Robin through the related-key differential analysis are possible with $2^{56}$ and $2^{72}$ time complexity, $2^{56}$ and $2^{69}$ chosen plaintext respectively.

An Error Detection and Recovery Algorithm in Digital Circuit Mimicking by Self-Repair on Cell (세포의 자가 치료 기능을 모사한 디지털 회로에서의 오류 검출 및 복구 알고리즘)

  • Kim, Soke-Hwan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.11
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    • pp.2745-2750
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    • 2015
  • Abstract should be placed here In this study, we propose an algorithm of the method of recovering quickly find the location of the error encountered during separate operations in the functional structure of complex digital circuits by mimicking the self-healing function of the cell. By the digital circuit was divided by 9 function block unit of function, proposes a method that It can quickly detect and recover the error position. It was the detection and recovery algorithms for the error location in the digital circuit of a complicated structure and could extended the number of function block for the $3{\times}3$ matrix structure on the dital circuit.

Directional Interpolation of Lost Block Using Difference of DC values and Similarity of AC Coefficients (DC값 차이와 AC계수 유사성을 이용한 방향성 블록 보간)

  • Lee Hong Yub;Eom Il Kyu;Kim Yoo Shin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.6C
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    • pp.465-474
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    • 2005
  • In this paper, a directional reconstruction of lost block in image over noisy channel is presented. DCT coefficients or pixel values in the lost blocks are recovered by using the linear interpolation with available neighboring blocks that are adaptively selected by the directional measure that are composed of the DDC (Difference of DC opposite blocks)and SAC(Similarity of AC opposite blocks) between opposite blocks around lost blocks. The proposed directional recovery method is effective for the strong edge and texture regions because we do not make use of the fixed 4-neighboring blocks but exploit the varying neighboring blocks adaptively by the directional information in the local image. In this paper, we describe the novel directional measure(CDS: Combination of DDC and SAC) composed of the DDC and the SAC and select the usable block to recover the lost block with the directional measure. The proposed method shows about 0.6dB PSNR improvement in average compared to the conventional methods.

Growth Responses and Regrowth to Low Temperature of Nine Native Moss Species

  • Gong, Gyeong Yeop;Jeong, Kyeong Jin;Lee, Sang Woo;Yun, Jae Gill
    • Journal of People, Plants, and Environment
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    • v.22 no.6
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    • pp.575-582
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    • 2019
  • Moss is used as an important material in indoor landscaping as well as outdoor landscaping. Moss is vivid green during growth and excellent in ornamental value. But when temperature drops, moss stops growth, turns brown or loses its ornamental value. In the present experiment, for the purpose of classifying native mosses according to the growth response to low temperature, the temperature of the plant growth chamber was set to 15℃/5℃ (16h/8h, day/night) and 5℃ (24h) for 8 weeks using nine native moss species. Thereafter, the temperature of the plant growth chamber was set to 20℃, and then the changes of moss block area and moss color were measured. The changes of moss block area and moss color were measured using a Photoshop program, after each moss block was photographed. As a result, Atrichum undulatum (Hedw.). Beauv., Etodon luridus (Griff.) A. Jaeger, Bachythecium plumosum (Hedw.) Schimp, Plagiomnium cuspidatum (Hedw.) T.J. Kop, and Hypnum plumaeforme Wilson showed a small decrease in moss block area at low temperature, and their recovery were the fastest at 20℃. These three species had higher green values at low temperature compared to other species, and the greenness increased rapidly at 20℃. On the other hand, Atrichum undulatum (Hedw.). Beauv., Marchantia polymorpha L., and Thuidium cymbifolium (Mitt.) A. Jaeger showed the smallest block area at low temperature and the lowest recovery even at 20℃. Their green values also decreased significantly at low temperature, and maintained low green value even at 20℃. These results showed that these three moss species are sensitive to low temperature. The remaining Myuroclada maximowiczii, Plagiomnium cuspidatum, and H. erectiusculum showed moderate responses to low temperature compared to other six species of mosses.

Design of Clock and Data Recovery Circuit for 622Mbps Optical Network (622Mbps급 광 통신망용 버스트모드 클럭/데이터 복원회로 설계)

  • Moon, Sung-Young;Lee, Sung-Chul;Moon, Gyu
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.46 no.2
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    • pp.57-63
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    • 2009
  • In this Paper, a novel 622Mbps burst-mode clock and data recovery (CDR) circuit is proposed for passive optical network (PON) applications. The CDR circuit is composed of CDR(Clock and Data Recovery) block and PLL(Phase Locked Loop) block. Lock dynamics is accomplished on the first data transition and data are sampled in the optimal point. The CDR circuit is realized in 0.35um CMOS process technology. With input pseudo-random bit sequences(PRBS) of $2^7-1$, the simulations show 17ps peak-to-peak retimed data jitter characteristics. The experimental results show that the proposed CDR circuits are operating as expected, recovering an incoming 622Mbps burst-mode input data without errors.

Key Recovery Attacks on Zorro Using Related-Key Differential Characteristics, and Collision Attacks on PGV-Zorro (Zorro의 연관키 차분특성을 이용한 키 복구 공격 및 PGV-Zorro의 충돌쌍 공격)

  • Kim, Giyoon;Park, Eunhu;Lee, Jonghyeok;Jang, Sungwoo;Kim, Jihun;Kim, Hangi;Kim, Jongsung
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.28 no.5
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    • pp.1059-1070
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    • 2018
  • The block cipher Zorro is designed to reduce the implementation cost for side-channel countermeasure. It has a structure similar to AES, but the number of S-Boxes used is small. However, since the master key is used as the round key, it can be vulnerable to related key attacks. In this paper, we show key recovery attacks on Zorro using related-key differential characteristics. In addition, the related key differential characteristics are fatal when Zorro is used as the base block cipher of the hash function. In this paper, we describe how these characteristics can be linked to collision attacks in the PGV models.

Stellate Ganglion Block for the Treatment of Classic Migraine -A case report- (성상신경절차단에 의한 전형적 편두통의 치료경험 -증례보고-)

  • Yeo, Sang-Im;Kim, Jeng-Il;Ban, Jong-Seuk;Min, Byung-Woo
    • The Korean Journal of Pain
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    • v.8 no.1
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    • pp.120-123
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    • 1995
  • We had undertaken a stellate ganglion block everyday for the treatment of a classic migraine patient who is a twenty seven a year old male. He had experienced a very severe and frequent attack two or three times a month for several years. after ten times of stellate ganglion block, a headache attack occurred mildly. Seventeen times of stellate ganglion block were undertaken totally. Now he feels better. The intensity and the frequency of headache attack are markedly decreased. The pathophysiology and theraphy of classic migraine are unclear. The mechanism of stellate ganglion block for classic migraine treatment is also unknown. However, we think the stellate ganglion block contributes the improvement of hypothalamic blood flow, the recovery of homeostasis, and the weakening of sympathetic overactivity.

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