• Title/Summary/Keyword: coding parameters

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Genetic Diversity of Barley Cultivars as Revealed by SSR Masker

  • Kim, Hong-Sik;Park, Kwang-Geun;Baek, Seong-Bum;Suh, Sae-Jung;Nam, Jung-Hyun
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.47 no.5
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    • pp.379-383
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    • 2002
  • Allelic diversity of 44 microsatellite marker loci originated from the coding regions of specific genes or the non-coding regions of barley genome was analyzed for 19 barley genotypes. Multi-allelic variation was observed at the most of marker loci except for HVM13, HVM15, HVM22, and HVM64. The number of different alleles ranged from 2 to 12 with a mean of 4.0 alleles per micro-satellite. Twenty-one alleles derived from 10 marker loci are specific for certain genotypes. The level of polymorphism (Polymorphic Information Content, PIC) based on the band pattern frequencies among genotypes was relatively high at the several loci such as HVM3, HVM5, HVM14, HVM36, HVM62 and HVM67. In the cluster analysis using genetic similarity matrix calculated from microsatellite-derived DNA profiles, two major groups were classified and the spike-row type was a major factor for clustering. Correlation between genetic similarity matrices based on microsatellite markers and pedigree data was highly significant ($r=0.57^{**}$), but these two parameters were moderately associated each other. On the other hand, RAPD-based genetic similarity matrix was more highly associated with microsatellite-based genetic similarity ($r=0.63^{**}$) than coefficient of parentage.

Fuzzy Model Identification using a mGA Hybrid Schemes (mGA의 혼합된 구조를 사용한 퍼지 모델 동정)

  • Ju, Yeong-Hun;Lee, Yeon-U;Park, Jin-Bae
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.49 no.8
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    • pp.423-431
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    • 2000
  • This paper presents a systematic approach to the input-output data-based fuzzy modeling for the complex and uncertain nonlinear systems, in which the conventional mathematical models may fail to give the satisfying results. To do this, we propose a new method that can yield a successful fuzzy model using a mGA hybrid schemes with a fine-tuning method. We also propose a new coding method fo chromosome for applying the mGA to the structure and parameter identifications of fuzzy model simultaneously. During mGA search, multi-purpose fitness function with a penalty process is proposed and adapted to guarantee the accurate and valid fuzzy modes. This coding scheme can effectively represent the zero-order Takagi-Sugeno fuzzy model. The proposed mGA hybrid schemes can coarsely optimize the structure and the parameters of the fuzzy inference system, and then fine tune the identified fuzzy model by using the gradient descent method. In order to demonstrate the superiority and efficiency of the proposed scheme, we finally show its applications to two nonlinear systems.

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Bitrate Allocation Method among Sources of Higher Layer for Spatial Scalable Video Coding (공간계층형 영상부호화에서 상위계층 영상간 부호화율 배분방법)

  • 권순각;김태석;최재각
    • Journal of KIISE:Information Networking
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    • v.29 no.6
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    • pp.749-754
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    • 2002
  • In this paper, We propose a titrate allocation method in which the bitrates of the videos for the lower layer are restricted by constant titrate, but those of the higher layer are assigned to have the uniform picture quality, for the multiplexing system of multiple spatial scalable video sources. We first find an approximated model of distortion-bitrate for the MPEG-2 spatial scalable video coding system, then we obtain the bitrate for each source to have constant distortion ratio among the sources by using the approximated model parameters for real-time simple implementation. It is shown by simulation that the proposed bandwidth allocation can keep almost constant picture Quality ratio among the sources of higher layer.

Design and Implementation of the 155Mbps Adaptive CODEC for Ka-band Satellite Communications

  • Park, Eun-A;Chang, Dae-Ig;Kim, Nae-Soo
    • Proceedings of the IEEK Conference
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    • 2002.07c
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    • pp.1940-1943
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    • 2002
  • In this paper, we presented the design and implementation of 155Mbps satellite Modem adaptively compensated against the rain attenuation. In order to compensate the rain attenuation over high-speed satellite ink, the adaptive coding schemes with variable coding rates and the pragmatic TCM that can be decoded both the QPSK and TC-8PSK using same Viterbi decoder was studied and analyzed. The pragmatic TCM with rate 213, selected to the optimal parameters for implementation, was modeled by VHDL in this paper. The key design issues are how to achieve a high data rate and how to integrated into a single ASIC chip various functions such as the different data rates, Scrambler/descrambler, Interleaver, Encoder/decoder, and BPSK/QPSK/8PSK modulator/demodulator. The implemented 155M0ps adaptive MODEM has the simplified interface circuits among the many functional blocks, and parallel processing architecture to achieve the high data rate. This 155Mbps adaptive MODEM was designed and implemented by single ASIC chip with the 0.25 $\mu\textrm{m}$ CMOS standard cell technology.

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A Semantic-based rate control method for motion video coding (동영상 부호화를 위한 의미 기반 Rate control 기법)

  • 이봉호;전경재;곽노윤;강태하;황병원
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.3B
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    • pp.529-540
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    • 2000
  • This is paper presents the semantic based rate-control method which is based on very low bit rate video coding standards H.263 plus, applied on very low bit rate applications. Previous rate control methods control the generated bit rates by setting the optimum quantization parameters per macro block unit on frame. But, in this paper, we added the pre-processing algorithm, semantic region recognition and assignment of priority algorithm, to obtain the subjective quality enhancement. This work aims to improve the subjective quality of skin color region or face by using unimportant background region's bit resources.

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A Distortion Estimation Method Using Integer Operations in H.264/AVC Encoder (H.264/AVC 부호화기에서 정수 연산을 사용한 왜곡치 예측 방식)

  • Moon, Jeong-Mee;Kim, Jae-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.1C
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    • pp.63-71
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    • 2009
  • In this paper, a new low-complexity distortion estimation method for H.264 rate-distortion optimized mode decision is proposed. The coding processes, such as DCT, quantization, inverse quantization, inverse DCT, and reconstruction are needed to compute the distortion in an H.264 encoder. To reduce these processes, we estimate distortion using integer operations with coefficients obtained in the quantization process. Inverse quantization, inverse DCT, and reconstruction processes are not needed by the proposed method. For quantization parameters 24 to 36, experimental results show that the time saving of rate-distortion optimized mode decision is on average 29 % and as high as 42 % with negligible degradation in coding performance.

Medical Image Compression Using Quincunx Wavelets and SPIHT Coding

  • Beladgham, Mohammed;Bessaid, Abdelhafid;Taleb-Ahmed, Abdelmalik;Boucli Hacene, Ismail
    • Journal of Electrical Engineering and Technology
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    • v.7 no.2
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    • pp.264-272
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    • 2012
  • In the field of medical diagnostics, interested parties have resorted increasingly to medical imaging. It is well established that the accuracy and completeness of diagnosis are initially connected with the image quality, but the quality of the image is itself dependent on a number of factors including primarily the processing that an image must undergo to enhance its quality. This paper introduces an algorithm for medical image compression based on the quincunx wavelets coupled with SPIHT coding algorithm, of which we applied the lattice structure to improve the wavelet transform shortcomings. In order to enhance the compression by our algorithm, we have compared the results obtained with those of other methods containing wavelet transforms. For this reason, we evaluated two parameters known for their calculation speed. The first parameter is the PSNR; the second is MSSIM (structural similarity) to measure the quality of compressed image. The results are very satisfactory regarding compression ratio, and the computation time and quality of the compressed image compared to those of traditional methods.

A MFCC-based CELP Speech Coder for Server-based Speech Recognition in Network Environments (네트워크 환경에서 서버용 음성 인식을 위한 MFCC 기반 음성 부호화기 설계)

  • Lee, Gil-Ho;Yoon, Jae-Sam;Oh, Yoo-Rhee;Kim, Hong-Kook
    • MALSORI
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    • no.54
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    • pp.27-43
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    • 2005
  • Existing standard speech coders can provide speech communication of high quality while they degrade the performance of speech recognition systems that use the reconstructed speech by the coders. The main cause of the degradation is that the spectral envelope parameters in speech coding are optimized to speech quality rather than to the performance of speech recognition. For example, mel-frequency cepstral coefficient (MFCC) is generally known to provide better speech recognition performance than linear prediction coefficient (LPC) that is a typical parameter set in speech coding. In this paper, we propose a speech coder using MFCC instead of LPC to improve the performance of a server-based speech recognition system in network environments. However, the main drawback of using MFCC is to develop the efficient MFCC quantization with a low-bit rate. First, we explore the interframe correlation of MFCCs, which results in the predictive quantization of MFCC. Second, a safety-net scheme is proposed to make the MFCC-based speech coder robust to channel error. As a result, we propose a 8.7 kbps MFCC-based CELP coder. It is shown from a PESQ test that the proposed speech coder has a comparable speech quality to 8 kbps G.729 while it is shown that the performance of speech recognition using the proposed speech coder is better than that using G.729.

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A Random Deflected Subgradient Algorithm for Energy-Efficient Real-time Multicast in Wireless Networks

  • Tan, Guoping;Liu, Jianjun;Li, Yueheng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.10
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    • pp.4864-4882
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    • 2016
  • In this work, we consider the optimization problem of minimizing energy consumption for real-time multicast over wireless multi-hop networks. Previously, a distributed primal-dual subgradient algorithm was used for finding a solution to the optimization problem. However, the traditional subgradient algorithms have drawbacks in terms of i) sensitivity to iteration parameters; ii) need for saving previous iteration results for computing the optimization results at the current iteration. To overcome these drawbacks, using a joint network coding and scheduling optimization framework, we propose a novel distributed primal-dual Random Deflected Subgradient (RDS) algorithm for solving the optimization problem. Furthermore, we derive the corresponding recursive formulas for the proposed RDS algorithm, which are useful for practical applications. In comparison with the traditional subgradient algorithms, the illustrated performance results show that the proposed RDS algorithm can achieve an improved optimal solution. Moreover, the proposed algorithm is stable and robust against the choice of parameter values used in the algorithm.

Dimmable Spatial Intensity Modulation for Visible-light Communication: Capacity Analysis and Practical Design

  • Kim, Byung Wook;Jung, Sung-Yoon
    • Current Optics and Photonics
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    • v.2 no.6
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    • pp.532-539
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    • 2018
  • Multiple LED arrays can be utilized in visible-light communication (VLC) to improve communication efficiency, while maintaining smart illumination functionality through dimming control. This paper proposes a modulation scheme called "Spatial Intensity Modulation" (SIM), where the effective number of turned-on LEDs is employed for data modulation and dimming control in VLC systems. Unlike the conventional pulse-amplitude modulation (PAM), symbol intensity levels are not determined by the amplitude levels of a VLC signal from each LED, but by counting the number of turned-on LEDs, illuminating with a single amplitude level. Because the intensity of a SIM symbol and the target dimming level are determined solely in the spatial domain, the problems of conventional PAM-based VLC and related MIMO VLC schemes, such as unstable dimming control, non uniform illumination functionality, and burdens of channel prediction, can be solved. By varying the number and formation of turned-on LEDs around the target dimming level in time, the proposed SIM scheme guarantees homogeneous illumination over a target area. An analysis of the dimming capacity, which is the achievable communication rate under the target dimming level in VLC, is provided by deriving the turn-on probability to maximize the entropy of the SIM-based VLC system. In addition, a practical design of dimmable SIM scheme applying the multilevel inverse source coding (MISC) method is proposed. The simulation results under a range of parameters provide baseline data to verify the performance of the proposed dimmable SIM scheme and applications in real systems.