• Title, Summary, Keyword: orthogonal group

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INFINITE FAMILIES OF RECURSIVE FORMULAS GENERATING POWER MOMENTS OF TERNARY KLOOSTERMAN SUMS WITH SQUARE ARGUMENTS ASSOCIATED WITH O-(2n, q)

  • Kim, Dae-San
    • Journal of the Korean Mathematical Society
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    • v.48 no.2
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    • pp.267-288
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    • 2011
  • In this paper, we construct eight infinite families of ternary linear codes associated with double cosets with respect to certain maximal parabolic subgroup of the special orthogonal group $SO^-$(2n, q). Here q is a power of three. Then we obtain four infinite families of recursive formulas for power moments of Kloosterman sums with square arguments and four infinite families of recursive formulas for even power moments of those in terms of the frequencies of weights in the codes. This is done via Pless power moment identity and by utilizing the explicit expressions of exponential sums over those double cosets related to the evaluations of "Gauss sums" for the orthogonal groups $O^-$(2n, q).

A Novel AOCG-OFDM Modulation Technique for Variable-high-bit-rate (가변성 고속 비트율을 위한 새로운 AOCG-OFDM 변조 기술)

  • Kong, Hyung-Yun
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.10 no.2
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    • pp.159-165
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    • 2010
  • The Multi-code (Mc) modulation has been developed for high-speed data transmission over the wireless environments, but it suffers two critical problems due to the limited resource of Orthogonal Codes (OC) and high Peak-Average Power Ratio (PAPR). In this paper, we propose a novel modulation technique called AOCG [1] (Advanced Orthogonal Code Group)-OFDM (Orthogonal Frequency Division Multiplexing) to solve the above problems and obtain the variable high bit rates which can be controlled by the four parameters depending on the quality of services (QoS) required by users.

Performance Analysis of Interleaved Super Orthogonal Convolutional Coded UWB-IR System for Wireless Fading Environment (무선 페이딩 환경에 적합한 인터리브된 초직교 길쌈 부호화 UWB-IR 시스템의 성능 분석)

  • Kim Chang-Joong;Lee Ho-Kyoung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.16 no.6
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    • pp.556-562
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    • 2005
  • In this paper, we propose interleaved super-orthogonal convolutional coded ultra wide-band impulse radio(ISOC-UWB-IR) system, and analyze its performance. The proposed system uses interleaver and deinterleaver to decorrelate the temporal correlation of the fading process and to obtain the diversity gain. We also suggest the three types of interleavers, which are pulse-wise interleaver(PI), pulse sub-group-wise interleaver(PSGI), and pulse group-wise interleaver(PGI). Performance analysis result shows that the interleaving scheme, rather than the code rate of super orthogonal convolutional code(SOC) encoder, affects the performance for the Rayleigh fading channel.

Quasi-Orthogonal STBC with Iterative Decoding in Bit Interleaved Coded Modulation

  • Sung, Chang-Kyung;Kim, Ji-Hoon;Lee, In-Kyu
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.4A
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    • pp.426-433
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    • 2008
  • In this paper, we present a method to improve the performance of the four transmit antenna quasi-orthogonal space-time block code (STBC) in the coded system. For the four transmit antenna case, the quasi-orthogonal STBC consists of two symbol groups which are orthogonal to each other, but intra group symbols are not. In uncoded system with the matched filter detection, constellation rotation can improve the performance. However, in coded systems, its gain is absorbed by the coding gain especially for lower rate code. We propose an iterative decoding method to improve the performance of quasi-orthogonal codes in coded systems. With conventional quasi-orthogonal STBC detection, the joint ML detection can be improved by iterative processing between the demapper and the decoder. Simulation results shows that the performance improvement is about 2dB at 1% frame error rate.

Spatial extrapolation of pressure time series on low buildings using proper orthogonal decomposition

  • Chen, Yingzhao;Kopp, Gregory A.;Surry, David
    • Wind and Structures
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    • v.7 no.6
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    • pp.373-392
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    • 2004
  • This paper presents a methodology for spatial extrapolation of wind-induced pressure time series from a corner bay to roof locations on a low building away from the corner through the application of proper orthogonal decomposition (POD). The approach is based on the concept that pressure time series in the far field can be approximated as a linear combination of a series of modes and principal coordinates, where the modes are extracted from the full roof pressure field of an aerodynamically similar building and the principal coordinates are calculated from data at the leading corner bay only. The reliability of the extrapolation for uplift time series in nine bays for a cornering wind direction was examined. It is shown that POD can extrapolate reasonably accurately to bays near the leading corner, given the first three modes, but the extrapolation degrades further from the corner bay as the spatial correlations decrease.

Orthogonal Stimulus-Response as a Tool to Formulate Traditional Chinese Medicinal Herbal Combination - New Scientific-Based TCM Herbal Formulating Method -

  • Loh, Yean Chun;Tan, Chu Shan;Yam, Mun Fei;Oo, Chuan Wei;Omar, Wan Maznah Wan
    • Journal of Pharmacopuncture
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    • v.21 no.3
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    • pp.203-206
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    • 2018
  • Objectives: There is an increasing number of complex diseases that are progressively more difficult to be controlled using the conventional "single compound, single target" approach as demonstrated in our current modern drug development. TCM might be the new cornerstone of treatment alternative when the current treatment option is no longer as effective or that we have exhausted it as an option. Orthogonal stimulus-response compatibility group study is one of the most frequently employed formulas to produce optimal herbal combination for treatment of multi-syndromic diseases. This approach could solve the relatively low efficacy single drug therapy usage and chronic adverse effects caused by long terms administration of drugs that has been reported in the field of pharmacology and medicine Methods: The present review was based on the Science Direct database search for those related to the TCM and the development of antihypertensive TCM herbal combination using orthogonal stimulus-response compatibility group studies approach. Results: Recent studies have demonstrated that the orthogonal stimulus-response compatibility group study approach was most frequently used to formulate TCM herbal combination based on the TCM principles upon the selection of herbs, and the resulting formulated TCM formula exhibited desired outcomes in treating one of global concerned complex multi-syndromic diseases, the hypertension. These promising therapeutic effects were claimed to have been attributed by the holistic signaling mechanism pathways employed by the crude combination of herbs. Conclusion: The present review could serve as a guide and prove the feasibility of TCM principles to be used for future pharmacological drug research development.

An Optimized Double-ABBA Quasi-Orthogonal Space Time Code with PIC Group Decoding (PIC 그룹 복호화를 이용한 최적화된 Double-ABBA 유사 직교 시공간 부호)

  • Hanif, Mohammad Abu;Lee, Moon Ho;Park, Ju Yong
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.1
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    • pp.21-26
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    • 2013
  • In this paper we propose a system where we divide the group with 2 symbols. The two added symbols are separated by multiplexing and later added using the DE-multiplexing technique. In our proposed system a simple Partial Interference Cancelation (PIC) group decoding scheme is used for Double-ABBA(D-ABBA) Quasi-Orthogonal Space Time Code, which reduces the decoding complexity for the higher order Multiple Input Multiple Output (MIMO) space time block coding. Finally we compare the proposed scheme performance using the different modulation schemes.

THE CLASSIFICATION OF SELF-ORTHOGONAL CODES OVER ℤp2 OF LENGTHS ≤ 3

  • Choi, Whan-Hyuk;Kim, Kwang Ho;Park, Sook Young
    • Korean Journal of Mathematics
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    • v.22 no.4
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    • pp.725-742
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    • 2014
  • In this paper, we find all inequivalent classes of self-orthogonal codes over $Z_{p^2}$ of lengths $l{\leq}3$ for all primes p, using similar method as in [3]. We find that the classification of self-orthogonal codes over $Z_{p^2}$ includes the classification of all codes over $Z_p$. Consequently, we classify all the codes over $Z_p$ and self-orthogonal codes over $Z_{p^2}$ of lengths $l{\leq}3$ according to the automorphism group of each code.

Optimum Design of Transverse Flux Linear Motor for Maximizing Thrust Force (추력을 최대화하기 위한 횡자속 선형전동기의 최적설계)

  • Hong, D.K.;Woo, B.C.;Kang, D.H.;Jang, J.W.;Kim, J.M.;Park, G.W.
    • Proceedings of the KIEE Conference
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    • pp.1159-1161
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    • 2005
  • This study uses a design of experiments to explain correlations between the objective function and design variables. Analysis of means, analysis of variance and table of orthogonal array were carried out. The change of shape design variable for TFLM based on the table of orthogonal array is made. Therefore this study carried to decide design variables for maximizing thrust force of TFLM. we showed improved design variables.

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