• Title/Summary/Keyword: Symmetric coding

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Jeju Jong-Nang Channel Code III (제주 정낭(錠木) 채널 Code III)

  • Park, Ju-Yong;Kim, Jeong-Su;Lee, Moon-Ho
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.15 no.5
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    • pp.91-103
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    • 2015
  • This paper presents "The 3-User NOR switching channel based on interference decoding with receiver cooperation" in succession to "Jeju Jong Nang channel code I, II". The Jeju Jong Nang code is considered as one of the earliest human binary coded communication (HBCC) in the world with a definite "1" or "0" binary symbolic analysis of switching circuits. In this paper, we introduce a practical example of interference decoding with receiver cooperation based on the three user Jong Nang NOR switching channel. The proposed system models are the three user Jong Nang (TUJN) NOR logic switching on-off, three-user injective deterministic NOR switching channel and Gaussian interference channel (GIC) with receiver cooperation. Therefore, this model is well matched to Shannon binary symmetric and erasure channel capacity. We show the applications of three-user Gaussian interference decoding to obtain deterministic channels which means each receiver cooperation helps to adjacent others in order to increase degree of freedom. Thus, the optimal sum rate of interference mitigation through adjacent receiver cooperation achieves 7 bits.

A Performance Evaluation on Classic Mutual Exclusion Algorithms for Exploring Feasibility of Practical Application (실제 적용 타당성 탐색을 위한 고전적 상호배제 알고리즘 성능 평가)

  • Lee, Hyung-Bong;Kwon, Ki-Hyeon
    • KIPS Transactions on Computer and Communication Systems
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    • v.6 no.12
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    • pp.469-478
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    • 2017
  • The mutual exclusion is originally based on the theory of race condition prevention in symmetric multi-processor operating systems. But recently, due to the generalization of multi-core processors, its application range has been rapidly shifted to parallel processing application domain. POSIX thread, WIN32 thread, and Java thread, which are typical parallel processing application development environments, provide a unique mutual exclusion mechanism for each of them. Applications that are very sensitive to performance in these environments may want to reduce the burden of mutual exclusion, even at some cost, such as inconvenience of coding. In this study, we implement Dekker's and Peterson's algorithm in the form of busy-wait and processor-yield in various platforms, and compare the performance of them with the built-in mutual exclusion mechanisms to evaluate the usability of the classic algorithms. The analysis result shows that Dekker's algorithm of processor-yield type is superior to the built-in mechanisms in POSIX and WIN32 thread environments at least 2 times and up to 70 times, and confirms that the practicality of the algorithm is sufficient.

A Study on Enhancement of Digital Image Performance Using Dual Tree Wavelet Transformation in Non-separable Image Processing (비분리 영상처리에서 이중 트리 웨이브렛 변환을 사용한 디지털 영상 성능 개선에 관한 연구)

  • Lim, Joong-Hee;Jee, Inn-Ho
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.12 no.1
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    • pp.65-74
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    • 2012
  • In this paper, we explore the application of 2-D dual-tree discrete wavelet transform (DDWT), which is a directional and redundant transform, for image coding. DDWT introduces limited redundancy and allows the transform to provide approximate shift invariance and directionally selective filters while preserving the usual properties of perfect reconstruction and computational efficiency with good well-balanced frequency responses. Also, quincunx lattice yields a non separable 2D-wavelet transform, which is also symmetric in both horizontal and vertical direction. And non-separable wavelet transformation can generate sub-images of multiple degrees rotated versions. The proposed 2-D non-separable DDWT can provide efficient approximation for directional features of images schemes, such as edges and contours in images that are not aligned with the horizontal or vertical direction. Finally, non-separable image processing using DDWT services good performance.

Comparison of Hybridization Behavior between Double and Single Strand of Targets and the Application of Asymmetric PCR Targets in cDNA Microarray

  • Wei, Qing;Liu, Sanzhen;Huang, Jianfeng;Mao, Xueying;Chu, Xiaohui;Wang, Yu;Qiu, Minyan;Mao, Yumin;Xie, Yi;Li, Yao
    • BMB Reports
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    • v.37 no.4
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    • pp.439-444
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    • 2004
  • Double stranded targets on the cDNA microarray contain representatives of both the coding and noncoding strands, which will introduce hybridization competition with probes. Here, the effect of double and single strands of targets on the signal intensity and the ratios of Cy5/Cy3 within the same slide were compared. The results show that single stranded targets can increase the hybridization efficiency without changing the Cy5/Cy3 ratio. Based on these results, a new strategy was established by generating cDNA targets with asymmetric PCR, instead of conventional PCR, to increase the sensitivity of the cDNA microarray. Furthermore, the feasibility of this approach was validated. The results indicate that the cDNA microarray system based on asymmetric PCR is more sensitive, with no decrease in the reliability and reproducibility as compared with that based on conventional symmetric PCR.

A Study on Applications of Wavelet Bases for Efficient Image Compression (효과적인 영상 압축을 위한 웨이브렛 기저들의 응용에 관한 연구)

  • Jee, Innho
    • Journal of IKEEE
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    • v.21 no.1
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    • pp.39-45
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    • 2017
  • Image compression is now essential for applications such as transmission and storage in data bases. For video and digital image applications the use of long tap filters, while not providing any significant coding gain, may increase the hardware complexity. We use a wavelet transform in order to obtain a set of bi-orthogonal sub-classes of images; First, the design of short kernel symmetric analysis is presented in 1-dimensional case. Second, the original image is decomposed at different scales using a subband filter banks. Third, this paper is presented a technique for obtaining 2-dimensional bi-orthogonal filters using McClellan transform. It is shown that suggested wavelet bases is well used on wavelet transform for image compression. From performance comparison of bi-orthogonal filter, we actually use filters close to ortho-normal filters on application of wavelet bases to image analysis.

Performance Improvement of the battening Effect of the new Asymmetric Turbo Codes (새로운 비대칭 구조를 갖는 터보부호의 Flattening Effect의 성능향상에 관한 연구)

  • 정대호;정성태;김환용
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.6A
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    • pp.533-539
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    • 2002
  • It is well known the fact that turbo lodes has better performance as the number of iteration and the interleaver size increases in the AWGN channel environment. However, as the number of iteration and the interleaver size are increased, it is required much delay and computation for iterative decoding, and caused the flattening effect phenomenon which is very litter BER performance improvement at the arbitrary SNR. In this paper, We proposed the new asymmetric turbo codes, which consist of parallel concatenated turbo codes that use mixed types of component codes with different not only constraint length but also generate polynomial and analyzed its BER performance for log-MAP decoding algorithm with frame size of 128, 256, 512 and 1024 bits, and coding rate of 1/3. As a results of simulation, proposed asymmetric turbo codes verify that its BER performance is superior to conventional symmetric turbo codes. It can be also observed that the flattening effect phenomenon is very reduced by applying the proposed asymmetric turbo codes. It gains respectively 1.7dB ~2.5dB and 2.0dB~2.5dB SNR improvements in the case of short frame(128, 256) and large frame(512, 1024) size for the BER $10_{-4}$>/TEX> region.

High Bit-Rates Quantization of the First-Order Markov Process Based on a Codebook-Constrained Sample-Adaptive Product Quantizers (부호책 제한을 가지는 표본 적응 프로덕트 양자기를 이용한 1차 마르코프 과정의 고 전송률 양자화)

  • Kim, Dong-Sik
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.49 no.1
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    • pp.19-30
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    • 2012
  • For digital data compression, the quantization is the main part of the lossy source coding. In order to improve the performance of quantization, the vector quantizer(VQ) can be employed. The encoding complexity, however, exponentially increases as the vector dimension or bit rate gets large. Much research has been conducted to alleviate such problems of VQ. Especially for high bit rates, a constrained VQ, which is called the sample-adaptive product quantizer(SAPQ), has been proposed for reducing the hugh encoding complexity of regular VQs. SAPQ has very similar structure as to the product VQ(PQ). However, the quantizer performance can be better than the PQ case. Further, the encoding complexity and the memory requirement for the codebooks are lower than the regular full-search VQ case. Among SAPQs, 1-SAPQ has a simple quantizer structure, where each product codebook is symmetric with respect to the diagonal line in the underlying vector space. It is known that 1-SAPQ shows a good performance for i.i.d. sources. In this paper, a study on designing 1-SAPQ for the first-order Markov process. For an efficient design of 1-SAPQ, an algorithm for the initial codebook is proposed, and through the numerical analysis it is shown that 1-SAPQ shows better quantizer distortion than the VQ case, of which encoding complexity is similar to that of 1-SAPQ, and shows distortions, which are close to that of the DPCM(differential pulse coded modulation) scheme with the Lloyd-Max quantizer.