• Title/Summary/Keyword: $Q^2$AM

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CACB-Q2AM Modulation for High Bandwidth Efficiency and Constant Amplitude Signal Transmission (높은 대역폭 효율과 정진폭 신호 전송을 위한 CACB-Q2AM 변조)

  • Hong, Dae-Ki;Kang, Sung-Jin
    • Journal of Internet Computing and Services
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    • v.9 no.1
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    • pp.21-32
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    • 2008
  • In this paper, we propose new modulation schemes using the conventional CACB (Constant Amplitude Coded Multicode Biorthogonal) modulation with constant amplitude property. Also the proposed modulation schemes supports high transmission data rate by increasing the spectral efficiency, In order to obtain the high spectral efficiency, the $Q^2$AM (Quadrature-Quadrature Amplitude Modulation) and CA-$Q^2$AM (Constant Amplitude-$Q^2$AM) are used. We explain the simplest combining modulation scheme of CACB and $Q^2$AM (i.e., CACB-$Q^2$AM). However, this modulation scheme cannot support the constant amplitude property. Hence the first CACB-CA-$Q^2$AM (or CACB-CA-$Q^2$AM I) modulation scheme is proposed for the constant amplitude property. In the modulation scheme, the redundant constant amplitude encoding (spectral efficiency decrease) is required. Therefore, the second CACB-CA-$Q^2$AM (or CACB-CA-$Q^2$AM II) modulation scheme is proposed retaining the constant amplitude and the spectral efficiency. Computer simulations show that the proposed CACB-CA-$Q^2$AM II is the efficient modulation scheme.

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A study on the biorthogonally coded Q$^{2}$AM with constant envelope property (정진폭특성을 갖는 Birothogonal 부호로 부호화된 Q$^{2}$AM(Quadrature Quadrature Amplitude Modulation)에 관한 연구)

  • 박인재;심수보
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.9
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    • pp.2470-2480
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    • 1996
  • The energy efficiency and bandwidth efficiency are two important criterion in designing a modulation scheme Especially the constant envelope property must be considered as in the non-linear channel tht exit, for example in the nonlinear amplifiers for satellite repeater. The Q$^{2}$AM(Quadrature Quadrature Amplitude Modulation) is a new modulation scheme which combines the Q$^{2}$PSK(Quadrature Quadrature Phase Shift Keying) scheme which increases the signal space dimension and the QAM scheme which increases the bandwidth efficiency using the multi-level signal. The Q$^{2}$AM scheme has by far superior spectrum efficiency compared with the existing modulation schemes. Applying this scheme in the non-linear communication system increses the bandwidth efficiency but cannot envelop property. In this paper, a new system architecture is suggested which satisfies the large spectrum efficiency and constant envelope property by implementing the linear block coding prior to the Q$^{2}$AM modulation. the system has improved in performance by gaining the constant envelope and the additional coding gain. We able to observe the performance improvement of the suggested system(at BER=10$^{-5}$ ) of 4.4 dB for the 16-QAM and 0.7 dB for the Q$^{2}$PSK under the exact spectrum efficiency.

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SER Analysis of Arbitrary Two-Dimensional Signaling over Nonlinear AWGN Channels (비선형 채널에서 임의의 2차원 변조 신호의 SER 분석)

  • Lee, Jae-Yoon;Yoon, Dong-Weon;Cho, Kyong-Kuk
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.7A
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    • pp.738-745
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    • 2007
  • The non-linearity of HPA(high power amplifier) which is an important component in modern communications systems introduces AM/AM and AM/PM distortion so that the transmitted signal is deteriorated. And, the I/Q unbalances and phase error which are generated by non-ideal components are inevitable physical phenomena and lead to performance degradation when we implement a practical two-dimensional (2-D) modulation system. In this paper, we provide an exact and general expression involving the 2-D Gaussian Q-function for the error probabilities of arbitrary 2-D signaling with I/Q amplitude and phase unbalances in nonlinear additive white Gaussian noise (AWGN) channels by using the coordinate rotation and shifting technique.

Isolation and Identification of a Photosynthetic Bacterium Containing $Q_{10}$ ($Q_{10}$ 함유 광합성세균의 분리 및 동정)

  • Jeong, Soo Kyoung;Kim, Joong Kyun
    • Journal of Marine Bioscience and Biotechnology
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    • v.2 no.2
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    • pp.120-122
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    • 2007
  • A $Q_{10}$-producing photosynthetic bacterium was isolated from the silt at Nakdong river. The isolate had 1.55 mg of $Q_{10}$ per gram of dry cell. By the 16s-rDNA sequence analysis, the isolate was found to be Rhodobacter sphaeroids with 100% similarity (Genbank Accession No.=AM696701).

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A study on the types of unmarried single women based on their subjective perceptions on single life (독신 여성의 싱글생활에 대한 주관적 인식의 유형화 연구)

  • Wang, Seok Soon;Ryu, Kyung Hee
    • Korean Journal of Human Ecology
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    • v.22 no.6
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    • pp.615-631
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    • 2013
  • In this study, we attempt to explore various possible types of unmarried single women. Main purpose of the work is to find out possible types of unmarried single women in terms of their subjective views on single life based on Q methodology. Q methodology is a research method to study and understand people's "subjectivity" or their points of view. Here, we applied Q methodology to unmarried single women's subjective evaluation of their own lives. Thirty-one Q-questions were prepared through literature review, and were offered to eighteen unmarried single women. As a result, the subjects could be classified into the following five different types: (Type 1) 'I love my work but I hate pressure (for marriage) from others', (Type 2) 'I feel anxiety and stress (on marriage) but I am still waiting for a true love of mine', (Type 3) 'My life is most important and I'd rather enjoy my single life without restraint from others', (Type 4) 'I am weary of continuing my single life, and now I really want to get married and form a family', (Type 5) 'I don't feel comfortable with dating, marriage life etc, I'd rather continue my single life with less stress'.

An analysis of the arm-type site binding domain of bacteriophage .lambda. integrase

  • Cho, Eun-Hee
    • Journal of Microbiology
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    • v.33 no.2
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    • pp.165-170
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    • 1995
  • The 356 amino acid long lambda integrase protein of bacteriophage .lambda. constains two autonomous DNA binding domains with distinct sequence specificities. The amino terminal domain of integrase is implicated to bind to the arm-type sequences and the carboxyl domain interacts with the coretype sequencess. As a first step to understand the molecular mechanism of the integrase-DNA interaction at the arm-type site, the int(am)94 gene carrying an amber mutation at the 94th codon of the int was cloned under the control of the P$\_$tac/ promoter and the lacI$\_$q/ gene. The Int(am)94 mutant protein of amino terminal 93 amino acid residues can be produced at high level from a suppressor free strain harboring the plasmid pInt(am)94. The arm-type binding activity of Int(am)94 were measured in vivo and in vitro. A comparison of the arm-type binding properties of the wild-type integrase and the truncated Int(am)94 mutant indicated that the truncated fragment containing 93 amino acid residues carry all the determinants for DNA binding at the arm-type sites.

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Various Partial Charge Schemes on 3D-QSAR Models for P-gp Inhibiting Adamantyl Derivatives

  • Gadhe, Changdev G.;Madhavan, Thirumurthy;Kothandan, Gugan;Lee, Tae-Bum;Lee, Kyeong;Cho, Seung-Joo
    • Bulletin of the Korean Chemical Society
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    • v.32 no.5
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    • pp.1604-1612
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    • 2011
  • We developed three-dimensional quantitative structure activity relationship (3D-QASR) models for 17 adamantyl derivatives as P-glycoprotein (P-gp) inhibitors. Eighteen different partial charge calculation methods were tested to check the feasibility of the 3D-QSAR models. Best predictive comparative molecular field analysis (CoMFA) model was obtained with the Austin Model 1-Bond Charge Correction (AM1-BCC) atomic charge. The 3D-QSAR models were derived with CoMFA and comparative molecular similarity indices analysis (CoMSIA). The final CoMFA model ($q^2$ = 0.764, $r^2$ = 0.988) was calculated with an AM1-BCC charge and electrostatic parameter, whereas the CoMSIA model ($q^2$ = 0.655, $r^2$ = 0.964) was derived with an AM1-BCC charge and combined steric, electrostatic, hydrophobic and HB-acceptor parameters. Leave-five-out (LFO) cross-validation was also performed, which yielded good correlation coefficient for both CoMFA (0.801) and CoMSIA (0.656) models. Robustness of the developed models was checked further with 1000 run bootstrapping analyses, which gave an acceptable correlation coefficient for CoMFA (BS-$r^2$ = 0.997, BS-SD = 0.003) and CoMSIA (BS-$r^2$ = 0.996, BS-SD = 0.018).

A Study on the Subjectivity of the Meaning of Life for Middle-Aged Women (중년 여성의 삶의 의미에 대한 주관성 연구)

  • Kim, Boon-Han;Kim, Yoon-Sook;Choi, Jee-Eun;Jeon, Hye-Won;Jung, Yun
    • Korean Journal of Adult Nursing
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    • v.17 no.2
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    • pp.177-187
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    • 2005
  • Purpose: The purpose of the study was to investigate the meaning of the life of middle-aged women. Method: The research method employed Q-methodology. Thirty-one participants rated 30 selected Q-statements on a scale of 1~7. The collected data were analyzed using PC-QUNAL software. Result: Principal component analysis identified 4 types of the meaning of the life of middle-aged women. The categories were labeled 'May I help you?', 'Alone', 'Who am I ?', 'No regret'. Conclusion: We have found meaning of life of middle-aged women through this research. The study result could be data to perform effective nursing intervention for positive life of middle-aged women.

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Chemical Fixation and Sorption of Bentonite for the Removal of Heavy Metals in Acid Mine Drainage (AMD) (광산산성폐수에 함유된 중금속 처리를 위한 Chemical Fixation과 Bentonite의 흡착)

  • Jang, Am;Kim, In-S.
    • Journal of Korea Soil Environment Society
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    • v.5 no.2
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    • pp.33-43
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    • 2000
  • Mining wastes left without any proper treatment are affecting barren or arable lands where are located near and far from source through various pathway Metals are the only hazardous constituents that cannot be destroyed or altered by chemical or thermal methods and must be converted into the most insoluble and harmless form as possible, which have slower leaching rates than the original species, to prevent their reentry into the environment. Three types of chemical additives used in this study to immobilize heavy metals showed high immobilized capacity (q) and the efficiency (k) in the order of CaO, $Na_2$S.$5H_2$O, and $CaCO_3$. In addition, bentonite was considered as a good additive to remedy AM(Acid Mine Drainage) from the results of the physicochemical characteristics and immobilizing capacity. The Freundlich coefficients (n and k) from adsorption isotherm for the heavy metals adsorbed on 50g Benlonite were calculated.

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