• Title/Summary/Keyword: Linear encode

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Linear Unequal Error Protection Codes based on Terminated Convolutional Codes

  • Bredtmann, Oliver;Czylwik, Andreas
    • Journal of Communications and Networks
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    • v.17 no.1
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    • pp.12-20
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    • 2015
  • Convolutional codes which are terminated by direct truncation (DT) and zero tail termination provide unequal error protection. When DT terminated convolutional codes are used to encode short messages, they have interesting error protection properties. Such codes match the significance of the output bits of common quantizers and therefore lead to a low mean square error (MSE) when they are used to encode quantizer outputs which are transmitted via a noisy digital communication system. A code construction method that allows adapting the code to the channel is introduced, which is based on time-varying convolutional codes. We can show by simulations that DT terminated convolutional codes lead to a lower MSE than standard block codes for all channel conditions. Furthermore, we develop an MSE approximation which is based on an upper bound on the error probability per information bit. By means of this MSE approximation, we compare the convolutional codes to linear unequal error protection code construction methods from the literature for code dimensions which are relevant in analog to digital conversion systems. In numerous situations, the DT terminated convolutional codes have the lowest MSE among all codes.

An SNR Scalable Video Coding using Linearly Combined Motion Vectors

  • Ryu, Chang-Hoon;Byoungjun Han;Park, Kwang-Pyo;Yoon, Eung-Sik;Lee, Keun-Young
    • Proceedings of the IEEK Conference
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    • 2002.07a
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    • pp.50-53
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    • 2002
  • There are increasing needs to deliver the multimedia streaming over heterogeneous networks. When considering network environments and equipment accessed by user, delivery of video streaming must be scalable. There are many kinds of scalable video coding: spatial, temporal, SNR, and hybrid. The SNR scalable and spatial resolution, but different SNR quality with respect to layers. The 1-layer SNR scalable encoder produces SNR scalable video streams with ease. But, there is drift problem. Modified 1-layer approach does not have this problem but coding inefficiency, and is not MPEG-compliant. The present MPEG-compliant 2-layer encoder comes out to reduce coding rate. But it still use only base layer to encode whole layer. In this paper, we propose adaptive MPEG-compliant 2-layer encoder. Using linear combination algorithm, encoder use 1 motion vector to encode the sequences efficiently. By dong this, we can achieve the coding efficiency of SNR scalable coding.

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The Genetic Organization of the Linear Mitochondrial Plasmid mlp1 from Pleurotus ostreatus NFFA2

  • Kim, Eun-Kyoung;Youn, Hye-Sook;Koo, Yong-Bom;Roe, Jung-Hye
    • Journal of Microbiology
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    • v.35 no.4
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    • pp.264-270
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    • 1997
  • The structure of plasmid mlp1, a linear 10.2kb mitochondrial plasmid of Pleurotus ostreatus NFF A2 was determined by restriction enzyme mapping and partial sequencing. The plasmid encodes at least two proteins; a putative RNA polymerase showing homology to yeast mitochondrial RNA polymerase and to viral-encoded RNA polymerases, and a putative DNA polymerase showing significant homology to the family B thpe DNA polymerases. It also contains terminal inverted repeat sequences at both ends which are longer than 274 bp. A 1.6 kb EcoRI restriction fragment of m1p1 containing the putative RNA polymerase gene did not hybridize to the nuclear or motochondrial genomes from P. ostreatus, suggesting that it may encode plasmidspecific RNA polymerase. The gene fragment also did not hybridize with the RNA polymerase gene (RPO41) from Saccaromyces cerevisiae. The relationship between genes in m1p1 and those in another linear plasmid pC1K1 of Claviceps purpurea was examined by DNA hybridization. The result indicates that the genes for DNA and RNA polymerases are not closely related with those in C. purpurea.

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Assessment of the Contribution of Antagonistic Secondary Metabolites to the Antifungal and Biocontrol Activities of Pseudomonas fluorescens NBC275

  • Dutta, Swarnalee;Yu, Sang-Mi;Lee, Yong Hoon
    • The Plant Pathology Journal
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    • v.36 no.5
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    • pp.491-496
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    • 2020
  • An understanding of the contribution of secondary metabolites (SMs) to the antagonistic and biocontrol activities of bacterial biocontrol agents serves to improve biocontrol potential of the strain. In this study, to evaluate the contribution of each SM produced by Pseudomonas fluorescens NBC275 (Pf275) to its antifungal and biocontrol activity, we combined in silico analysis of the genome with our previous study of transposon (Tn) mutants. Thirteen Tn mutants, which belonged to 6 biosynthetic gene clusters (BGCs) of a total 14 BGCs predicted by the antiSMASH tool were identified by the reduction of antifungal activity. The biocontrol performance of Pf275 was significantly dependent on 2,4-diacetylphloroglucinol and pyoverdine. The clusters that encode for arylpolyene and an unidentified small linear lipopeptide influenced antifungal and biocontrol activities. To our knowledge, our study identified the contribution of SMs, such as a small linear lipopeptide and arylpolyene, to biocontrol efficacy for the first time.

A Color Image Watermarking Method for Embedding Audio Signal

  • Kim Sang Jin;Kim Chung Hwa
    • Proceedings of the IEEK Conference
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    • 2004.08c
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    • pp.631-635
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    • 2004
  • The rapid development of digital media and communication network urgently brings about the need of data certification technology to protect IPR (Intellectual property right). This paper proposed a new watermarking method for embedding contents owner's audio signal in order to protect color image IPR. Since this method evolves the existing static model and embeds audio signal of big data, it has the advantage of restoring signal transformed due to attacks. Three basic stages of watermarking include: 1) Encode analogue ID owner's audio signal using PCM and create new 3D audio watermark; 2) Interleave 3D audio watermark by linear bit expansion and 3) Transform Y signal of color image into wavelet and embed interleaved audio watermark in the low frequency band on the transform domain. The results demonstrated that the audio signal embedding in color image proposed in this paper enhanced robustness against lossy JPEG compression, standard image compression and image cropping and rotation which remove a part of image.

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Development of Education System Using Photo sensor and Control (광 센서를 이용한 교육용 시스템 개발과 제어)

  • Park, Seong-Wook;Lee, Deuk-Kee;Seo, Young-Taek
    • Proceedings of the KIEE Conference
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    • 2001.07e
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    • pp.30-32
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    • 2001
  • Thomson's jumping ring was first exhibited by Elihu Thomson in 1887 and modified to include the floating variation by John A. Fleming in 1890. This vivid demonstration of electromagnetic induction is still used in physics classrooms to illustrate Faraday's and Lenz's laws and is the basis for linear actuators for sorvo-mechanical purpose as well as induction heating and rail guns. The jumping ring apparatus of the type described in this study is used to demonstrate and educate the effects of electromagnetic induction. To verify control algorithm, a sensor system and a data control/measurement system is required. The sensor system consist of photo-interrupted and encode circuit which is designed to take voltage according to the position of ring.

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An Image Coding Technique Using the Image Segmentation (영상 영역화를 이용한 영상 부호화 기법)

  • 정철호;이상욱;박래홍
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.24 no.5
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    • pp.914-922
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    • 1987
  • An image coding technique based on a segmentation, which utilizes a simplified description of regions composing an image, is investigated in this paper. The proposed coding technique consists of 3 stages: segmentation, contour coding. In this paper, emphasis was given to texture coding in order to improve a quality of an image. Split-and-merge method was employed for a segmentation. In the texture coding, a linear predictive coding(LPC), along with approximation technique based on a two-dimensional polynomial function was used to encode texture components. Depending on a size of region and a mean square error between an original and a reconstructed image, appropriate texture coding techniques were determined. A computer simulation on natural images indicates that an acceptable image quality at a compression ratio as high as 15-25 could be obtained. In comparison with a discrete cosine transform coding technique, which is the most typical coding technique in the first-generation coding, the proposed scheme leads to a better quality at compression ratio higher than 15-20.

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Practical Implementation and Performance Evaluation of Random Linear Network Coding (랜덤 선형 네트워크 코딩의 실용적 설계 및 성능 분석)

  • Lee, Gyujin;Shin, Yeonchul;Koo, Jonghoe;Choi, Sunghyun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.40 no.9
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    • pp.1786-1792
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    • 2015
  • Random linear network coding (RLNC) is widely employed to enhance the reliability of wireless multicast. In RLNC encoding/decoding, Galois Filed (GF) arithmetic is typically used since all the operations can be performed with symbols of finite bits. Considering the architecture of commercial computers, the complexity of arithmetic operations is constant regardless of the dimension of GF m, if m is smaller than 32 and pre-calculated tables are used for multiplication/division. Based on this, we show that the complexity of RLNC inversely proportional to m. Considering additional overheads, i.e., the increase of header length and memory usage, we determine the practical value of m. We implement RLNC in a commercial computer and evaluate the codec throughput with respect to the type of the tables for multiplication/division and the number of original packets to encode with each other.

Micro-Machined Capacitive Linear Encoder with a Mechanical Guide (마이크로 머시닝으로 제작한 기계적 가이드를 갖는 정전용량 선형 인코더)

  • Kang, Daesil;Moon, Wonkyu
    • Journal of Sensor Science and Technology
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    • v.21 no.6
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    • pp.440-445
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    • 2012
  • Contact-type Linear Encoder-like Capacitive Displacement Sensor (CLECDiS) is a novel displacement sensor which has wide measurable range with high resolution. The sensor, however, is very sensitive to relative rotational alignment between stator and mover of the sensor as well as its displacement. In addition to, there can be some disturbances in the relative rotational alignment, so some noises occur in the sensor's output signal by the disturbances. This negative effect of the high sensitivity may become larger as increasing sensitivity. Therefore, this negative effect of the high sensitivity has to be compensated and reduced to achieve nanometer resolution of the sensor. In this study, a new type capacitive linear encoder with a mechanical guide is presented to reduce the relative rotational alignment problem. The presented method is not only to reduce the alignment problem, but also to assemble the sensor to the stage conveniently. The method is based on a new type CLECDiS that has mechanical guide autonomously. In the presented sensor, when the device is fabricated by micro-machining, the guide-rail is also fabricated on the surface of the sensor. By the direct fabrication of the guide-rail with high precision micro-machining, errors of the guide-rail can be reduced significantly. In addition, a manual yaw alignment is not required to obtain large magnitude of the output signal after the assembly of the sensor and the stage. The sensor movement is going to follow the guide-rail automatically. The prototype sensor was fabricated using the presented method, and we verify the feasibility experimentally.

Image Compression by Linear and Nonlinear Transformation of Computed Tomography (전산화단층촬영의 선형과 비선형변환에 의한 영상압축)

  • Park, Jae-Hong;Yoo, Ju-Yeon
    • Journal of the Korean Society of Radiology
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    • v.13 no.4
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    • pp.509-516
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    • 2019
  • In the linear transformation method, the original image is divided into a plurality of range blocks, and a partial transform system for finding an optimal domain block existing in the image for each range block is used to adjust the performance of the compression ratio and the picture quality, The nonlinear transformation method uses only the rotation transformation among eight shuffle transforms. Since the search is performed only in the limited domain block, the coding time is faster than the linear transformation method of searching the domain block for any block in the image, Since the optimal domain block for the range block can not be selected in the image, the performance may be lower than other methods. Therefore, the nonlinear transformation method improves the performance by increasing the approximation degree of the brightness coefficient conversion instead of selecting the optimal domain block, The smaller the size of the block, the higher the PSNR value, The higher the compression ratio is increased groups were quadtree block divided to encode the image at best.