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Non-Recursive Base Conversion Using a Deterministic Markov Process
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作者 Louis M. Houston 《Journal of Applied Mathematics and Physics》 2024年第6期2112-2118,共7页
We prove that non-recursive base conversion can always be implemented by using a deterministic Markov process. Our paper discusses the pros and cons of recursive and non-recursive methods, in general. And we include a... We prove that non-recursive base conversion can always be implemented by using a deterministic Markov process. Our paper discusses the pros and cons of recursive and non-recursive methods, in general. And we include a comparison between non-recursion and a deterministic Markov process, proving that the Markov process is twice as efficient. 展开更多
关键词 base conversion RECURSION Euclidean Division Geometric Series Markov Process
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THE XPS STUDY OF Cu-Co BASED CATALYSTS FOR SYNGAS CONVERSION TO ALCOHOLS
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作者 Wei CHU, Guo Xing XIONG, Heng Rong CHEN, Xie Xian GUO state key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Academia Sinica, P.O. Box 110, Dalian 116023 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第11期1031-1032,共2页
The copper-cobalt based catalysts were effective for higher alcohol synthesis, the surface state of the catalysts and the nature of the active sites were investigated by using XPS and XAES spectra, and some strong int... The copper-cobalt based catalysts were effective for higher alcohol synthesis, the surface state of the catalysts and the nature of the active sites were investigated by using XPS and XAES spectra, and some strong interactions were also observed, in each of the three cases, (after calcination, after reduction, and during the syngas reaction). 展开更多
关键词 XPS THE XPS STUDY OF Cu-Co baseD CATALYSTS FOR SYNGAS conversion TO ALCOHOLS Co OC Cu
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Experimental Investigation of All-Optical NRZ-DPSK to RZ-DPSK Format Conversion Based on TOAD
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作者 毛雅亚 盛新志 +2 位作者 吴重庆 张天雍 王颖 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第11期56-62,共7页
We propose and experimentally demonstrate a novel all-optical non-return-to-zero differential-phase-shift-keying (NRZ-DPSK) to return-to-zero differentiM-phase-shift-keying (RZ-DPSK) format conversion scheme. This... We propose and experimentally demonstrate a novel all-optical non-return-to-zero differential-phase-shift-keying (NRZ-DPSK) to return-to-zero differentiM-phase-shift-keying (RZ-DPSK) format conversion scheme. This scheme is based on the terahertz optical asymmetric demultiplexer (TOAD). A 10 Gb/s converted RZ-DPSK signal is obtained with a wide duty cycle tuning range from 16% to 66%. For all converted RZ-DPSK signals, the receiver sensitivities at BER of 10-9 are 0.4 to 1.7dB higher compared with the original NRZ-DPSK signal. The clear and open eye diagrams are presented to demonstrate the high quality format conversion performance. Moreover, the optical spectra show that this conversion is in a wavelength-preserving operation. 展开更多
关键词 NRZ Experimental Investigation of All-Optical NRZ-DPSK to RZ-DPSK Format conversion based on TOAD
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Research of whispered speech vocal tract system conversion based on universal background model and effective Gaussian components 被引量:1
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作者 CHEN Xueqin ZHAO Heming 《Chinese Journal of Acoustics》 2013年第4期400-410,共11页
Directing to the weakness of the present fixed values mapping methods (method_F), a vocal tract system conversion method based on the universal background model (UBM) is proposed for improving the performance of t... Directing to the weakness of the present fixed values mapping methods (method_F), a vocal tract system conversion method based on the universal background model (UBM) is proposed for improving the performance of the speech conversion system from Chinese whis- pered speech to normal speech. For the numerous components of UBM, the errors produced by the acoustical probability density statistical model can't be ignored. Thus an effective Gaus- sian mixture components chosen method based on the posterior probability summation of the minimum spectral distortion is developed to optimizing the system performance. The proposed method (method_U) is analyzed and compared using the performance index (PI) based on Itakura-Saito spectral distortion measure. It is shown experimentally that the performance of method_U is more stability for different speakers and different phonemes than that of method_F. The average PI of method_U is better than method_F. It is shown that by selecting effective Gaussian mixture components, the PI of method_U can be further improved 5.11%. Subjective auditory tests also show that the proposed method can improve the definition and intelligibility of conversion speech. 展开更多
关键词 Research of whispered speech vocal tract system conversion based on universal background model and effective Gaussian components UBM
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Terahertz optical asymmetric demultiplexer based tree-net architecture for all-optical conversion scheme from binary to its other 2^n radix based form 被引量:1
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作者 Jitendra Nath Roy Goutam Kumar Maity +1 位作者 Dilip Kumar Gayen Tanay Chattopadhyay 《Chinese Optics Letters》 SCIE EI CAS CSCD 2008年第7期536-540,共5页
To exploit the parallelism of optics in data processing, a suitable number system and an efficient encoding/decoding scheme for handling the data are very essential. In the field of optical computing and parallel info... To exploit the parallelism of optics in data processing, a suitable number system and an efficient encoding/decoding scheme for handling the data are very essential. In the field of optical computing and parallel information processing, several number systems like binary, quaternary, octal, hexadecimal, etc. have been used for different arithmetic and algebraic operations. Here, we have proposed an all-optical conversion scheme from its binary to its other 2^n radix based form with the help of terahertz optical asymmetric demultiplexer (TOAD) based tree-net architecture. 展开更多
关键词 TREE Terahertz optical asymmetric demultiplexer based tree-net architecture for all-optical conversion scheme from binary to its other 2~n radix based form NET
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Estimation method of glottal vocal efficiency based on conversion function of voice source
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作者 ZOU Yuan WAN Mingxi ZHAO Shouguo WANG Supin(1 Department of Biomedical Engineering, Xi’an Jiaotong University Xi’an 710049)(2 Institute of Microelectronics, Tsinghua University Beijing 100084)Received Sep. 12, 2000Revised May 9, 2002 《Chinese Journal of Acoustics》 2002年第4期332-342,共11页
This investigation was designed to approach a novel estimation method of glottal vocal efficiency (GVE) based on conversion function of voice source. The conversion function of voice source was defined the ratio of su... This investigation was designed to approach a novel estimation method of glottal vocal efficiency (GVE) based on conversion function of voice source. The conversion function of voice source was defined the ratio of supra-glottal acoustic voice source signal to the glottal air volume flow velocity waveform in frequency domain. A carefully designed in vivo canine larynx experiment and several human experiments including different vowels, pressed, falsetto, breath and typical laryngeal diseases were adopted to demonstrate this alternative GVE method. Compared with other vocal efficiency, it is shown that this method could eliminate the contribution from the super vocal tract transmission and resonance to GVE, and reflect the differences of phonation modes. The average magnitude of this conversion function in frequency domain represents GVE, and the variation of the magnitude in fundamental frequency is identical to AC/DC value. 展开更多
关键词 In SOURCE VOICE Estimation method of glottal vocal efficiency based on conversion function
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Amplification assisted difference frequency generation for efficient mid-infrared conversion based on monolithic tandem lithium niobate superlattice
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作者 TAO CHEN HAO LIU +1 位作者 WEI KONG RONG SHU 《Photonics Research》 SCIE EI 2017年第4期355-361,共7页
We report the investigation on the performance of an amplification assisted difference frequency generation(AA-DFG) system driven by pulsed pump and continuous-wave primary signal lasers. A monolithic tandem lithium n... We report the investigation on the performance of an amplification assisted difference frequency generation(AA-DFG) system driven by pulsed pump and continuous-wave primary signal lasers. A monolithic tandem lithium niobate superlattice was employed as the nonlinear crystal with a uniform grating section for the DFG process, followed by a chirp section for the optical parametric amplification process. The impacts of pump pulse shape, primary signal power, input beam diameter, and crystal structure on the pump-to-idler conversion efficiency of the AA-DFG system were comprehensively studied by numerically solving the coupled wave equations. It is concluded that square pump pulse and high primary signal power are beneficial to high pump-to-idler conversion efficiency. In addition, tighter input beam focus and smaller DFG length proportion could redeem the reduction in conversion efficiency resulting from wider acceptance bandwidths for the input lasers. We believe that such systems combining the merits of high stability inherited from cavity-free configuration and high efficiency attributed from the cascaded nonlinear conversion should be of great interest to a wide community,especially when the pulse shaping technique is incorporated. 展开更多
关键词 DFG Amplification assisted difference frequency generation for efficient mid-infrared conversion based on monolithic tandem lithium niobate superlattice OPO
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Single to 16-Channel Wavelength Conversion at 10 Gb/s Based on Cross-Gain Modulation of ASE in SOA
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作者 Zhang Xinliang, Huang Dexiu, Sun Junqiang , Liu DemingDepartment of Optoelectronic Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, P.R.China, 430074, 《光学学报》 EI CAS CSCD 北大核心 2003年第S1期485-486,共2页
Based on cross-gain modulation of Amplified Spontaneous Emission (ASE) in Semiconductor Optical Amplifier (SOA), single to 16-channel wavelength conversion at 10Gb/s is first demonstrated simultaneously without any ad... Based on cross-gain modulation of Amplified Spontaneous Emission (ASE) in Semiconductor Optical Amplifier (SOA), single to 16-channel wavelength conversion at 10Gb/s is first demonstrated simultaneously without any additional probe lights. 展开更多
关键词 ASE as Single to 16-Channel Wavelength conversion at 10 Gb/s based on Cross-Gain Modulation of ASE in SOA in of on dBm Figure
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Mutual optical format conversion between on-of keying and binary phase-shift keying based on stimulated brillouin scattering
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作者 张严 义理林 +2 位作者 张涛 李正璇 胡卫生 《Chinese Optics Letters》 SCIE EI CAS CSCD 2013年第10期15-17,共3页
We propose and experimentally demonstrate mutual optical format conversion between signals characterized as 10-Gb/s nonreturn-to-zero on-of-keying(NRZ-OOK) and NRZ binary phase-shift keying(BPSK) types. The conversion... We propose and experimentally demonstrate mutual optical format conversion between signals characterized as 10-Gb/s nonreturn-to-zero on-of-keying(NRZ-OOK) and NRZ binary phase-shift keying(BPSK) types. The conversion is based on stimulated Brillouin scattering(SBS) in a single-mode optical fber. An OOK signal is converted into a BPSK signal through optical carrier absorption, for which a SBS loss of 30 MHz is used in long-haul transmission. The converted BPSK signal is reverted to an OOK signal with a corresponding SBS gain of 30 MHz for direct detection. The proposed OOK-to-BPSK and BPSK-to-OOK format conversions can be implemented in transmitter and receiver nodes by using a laser source as the Brillouin pump. 展开更多
关键词 BPSK OOK Mutual optical format conversion between on-of keying and binary phase-shift keying based on stimulated brillouin scattering SBS
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Anticorrosion behavior of conversion coatings obtained from unbuffered cerium salts solutions on AA6061-T6 被引量:11
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作者 KIYOTA Sayuri VALDEZ Benjamin +2 位作者 STOYTCHEVA Margarita ZLATEV Roumen BASTIDAS Jose Maria 《Journal of Rare Earths》 SCIE EI CAS CSCD 2011年第10期961-968,共8页
The anticorrosive properties of cerium based conversion coatings deposited on AA6061-T6 alloy by immersion in tmbuffercd cerium chloride and cerium nitrate solutions in the presence of hydrogen peroxide were investiga... The anticorrosive properties of cerium based conversion coatings deposited on AA6061-T6 alloy by immersion in tmbuffercd cerium chloride and cerium nitrate solutions in the presence of hydrogen peroxide were investigated and characterized by potentiodynamic po- larization (PDP) and electrochemical impedance spectroscopy (EIS) in 0.5 mol/L NaCl aqueous solution. The microstructure and chemical composition of the protective films were examined by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). It was found that the best corrosion protection was afforded by the samples treated during 600 s in cerium chloride solution at pH values ~5.5-4, showing higher amounts of cerium and polarization resistance values greater than 10 f~ m2. Moreover, an ennoblement of the corro- sion potential and decreasing of the cathodic and anodic currents were obtained compared with the cerium nitrate solutions application. This behavior was attributed to the influence of the deposition parameters such as type of the salt anion, i.e., chelating effect and chaotropic characteristics, pH fluctuations in the conversion solution and deposition time. 展开更多
关键词 cerium based conversion coatings EIS PDP anticorrosion properties rare earths
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