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Discriminative tone model training and optimal integration for Mandarin speech recognition
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作者 黄浩 朱杰 《Journal of Southeast University(English Edition)》 EI CAS 2007年第2期174-178,共5页
Two discriminative methods for solving tone problems in Mandarin speech recognition are presented. First, discriminative training on the HMM (hidden Markov model) based tone models is proposed. Then an integration t... Two discriminative methods for solving tone problems in Mandarin speech recognition are presented. First, discriminative training on the HMM (hidden Markov model) based tone models is proposed. Then an integration technique of tone models into a large vocabulary continuous speech recognition system is presented. Discriminative model weight training based on minimum phone error criteria is adopted aiming at optimal integration of the tone models. The extended Baum Welch algorithm is applied to find the model-dependent weights to scale the acoustic scores and tone scores. Experimental results show that tone recognition rates and continuous speech recognition accuracy can be improved by the discriminatively trained tone model. Performance of a large vocabulary continuous Mandarin speech recognition system can be further enhanced by the discriminatively trained weight combinations due to a better interpolation of the given models. 展开更多
关键词 discriminative training minimum phone error tone modeling Mandarin speech recognition
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An Investigation on Feasibility of Pure Tone Sound Field Audiometry
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作者 邢光前 卜行宽 李芳丽 《The Journal of Biomedical Research》 CAS 1997年第1期14-18,共5页
It′s generally believed that the appropriate stimuli for sound field tests are warble tones and narrow band noise, while pure tone can only be a signal used in the free field and earphone listening conditions. In thi... It′s generally believed that the appropriate stimuli for sound field tests are warble tones and narrow band noise, while pure tone can only be a signal used in the free field and earphone listening conditions. In this study, we take a measurement of sound pressure distribution, sound field variability, and effects of frequency shifting on sound pressure levels (SPLs) at reference points of pure tone in an audiometric test room. It was found that the pure tone SPLs were also distributed uniformly at some sound field areas although it was not so well as warble tones. This indicated that the test results were relatively stable to head movement and/or frequency shifting in those regions, which was confirmed by the clinical measurements on 20 subjects with severe sensorineural hearing loss. Our study concluded that pure tones could also be suitable for sound field audiometry if subjects were seated at a proper location on the basis of the sound field calibrations. 展开更多
关键词 sound field audiometry test stimuli pure tone sound field calibration
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MANDARIN TONE RECOGNITION BASED ON WAVELET TRANSFORM AND HIDDEN MARKOV MODELING
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作者 Cheng Jun Yi Kechu Li Bingbing (National Key Laboratory on ISN, Xid/an University, Xi’an 710071) 《Journal of Electronics(China)》 2000年第1期1-8,共8页
This paper presents a method of tone recognition for Mandarin speech by using combination of wavelet transform and hidden Markov modeling techniques. A pitch detector based on singularity detection and multi-resolutio... This paper presents a method of tone recognition for Mandarin speech by using combination of wavelet transform and hidden Markov modeling techniques. A pitch detector based on singularity detection and multi-resolution analysis of wavelet transform is employed for estimation of pitch periods, and hidden Markov modeling with partition Gaussian mixtures probability density function is used for the tone recognition. The algorithm can provide recognition accuracy of 97.22% and 94.47% for speaker-dependent and speaker-independent tone recognition, respectively. 展开更多
关键词 PITCH detection tone recognition WAVELET TRANSFORM Hidden MARKOV model
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基于Gammatone滤波器分解的HRTF和GMM的双耳声源定位算法 被引量:5
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作者 李如玮 潘冬梅 +1 位作者 张爽 张永亚 《北京工业大学学报》 CAS CSCD 北大核心 2018年第11期1385-1390,共6页
针对数字助听器中现存声源定位算法精确度低和算法复杂度高的问题,提出一种新的双耳声源定位算法.首先,采集到的双耳声源信号通过Gammatone滤波器分解为若干个子带信号,根据能量的大小对数据进行压缩.然后,利用头相关传递函数(head-rela... 针对数字助听器中现存声源定位算法精确度低和算法复杂度高的问题,提出一种新的双耳声源定位算法.首先,采集到的双耳声源信号通过Gammatone滤波器分解为若干个子带信号,根据能量的大小对数据进行压缩.然后,利用头相关传递函数(head-related transfer function,HRTF)中包含的双耳线索,即双耳时间差、双耳声级差及耳间相关性,提取声源位置的特征.最后,声源的位置信息由高斯混合模型(Gaussian mixture model,GMM)分类器识别.实验结果表明,建议的算法具有高精确度、低复杂度及强鲁棒性. 展开更多
关键词 双耳声源定位 头相关函数 高斯混合模型(GMM) Gammatone滤波器 数据压缩 双耳线索
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Aeolian Tone from a Semi-Circular Cylinder in a Stream
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作者 Takayuki Yamagata Nozomi Saito Nobuyuki Fujisawa 《Journal of Flow Control, Measurement & Visualization》 2016年第1期30-37,共8页
Aeolian tone from a semi-circular cylinder in a uniform flow is studied experimentally for various angles of attack. It is found that the peak sound spectrum of the Aeolian tone from the semi-circular cylinder is smal... Aeolian tone from a semi-circular cylinder in a uniform flow is studied experimentally for various angles of attack. It is found that the peak sound spectrum of the Aeolian tone from the semi-circular cylinder is smaller than that from the circular cylinder and the lowest sound is observed around the zero angle of attack. This is due to the reduction in the fluctuating lift force on the semi-circular cylinder compared to that of the circular cylinder. This result suggests the validity of the analogy between the sound pressure level and the fluctuating lift force on a semi-circular cylinder in a stream. The flow visualization study also supports these results. 展开更多
关键词 Aeolian tone Semi-Circular Cylinder Fluctuating Lift Force Angle of Attack Flow Induced sound
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Traditional Chinese medicine five-tone therapy
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作者 Haoran Zhang 《Life Research》 2019年第2期80-83,共4页
From the perspective of the application of medical value orientation music therapy, this paper summarized the ancient Chinese sound therapy, such as shaman music therapy and five-tone therapy. It also compared five-to... From the perspective of the application of medical value orientation music therapy, this paper summarized the ancient Chinese sound therapy, such as shaman music therapy and five-tone therapy. It also compared five-tone therapy with Tibetan Singing bowl music therapy. The ancient music therapy is a kind of medical means which is oriented to the treatment effect. At first, it was mainly based on the music medical behavior of Taoist, and then gradually evolved into the modern treatment application of folk pentatonic therapy. On the basis of inheritance and development of ancient traditional music treatment, contemporary medicine proposed a new individualized music treatment. Therefore, the theory of five-tone therapy has updated the research on traditional Chinese music treatment theory and system, and will provide reference for the establishment of accurate music treatment system in the future. 展开更多
关键词 sound THERAPY music THERAPY TCM fiveelements FIVE toneS
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Analytical Solution and Numerical Simulation of Real-Time Dispersion Monitoring Using Tone Subcarrier
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作者 HUANG He~1 CHEN Fushen~1 JIANG Yi~2(1.Key Lab of Broadband Optic Fiber Transmission and Communication Networks,UESTC Chengdu 610054 China 2.R&D Center of Zhongxing Telecommunication Equipment Ltd.Co.Chongqing 400060 China) 《Journal of Electronic Science and Technology of China》 2003年第1期29-31,36,共4页
A method for online dispersion monitoring by adding a single in-band subcarrier tone isintroduced.According to the theoretical analysis,the dispersion monitor and measurement range aredetermined by the specific freque... A method for online dispersion monitoring by adding a single in-band subcarrier tone isintroduced.According to the theoretical analysis,the dispersion monitor and measurement range aredetermined by the specific frequency of the subcarrier tone.By using simulation tools,figures aboutrelationship between power of subcarrier tone and transmission distance in ideal condition are shown. 展开更多
关键词 DISPERSION subcarrier tone online dispersion monitoring model of optical transmission system simulation tools
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Characteristics analyzing and parametric modeling of the arc sound in CO_2 GMAW for on-line quality monitoring 被引量:8
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作者 马跃洲 马文斌 +1 位作者 瞿敏 陈剑虹 《China Welding》 EI CAS 2006年第2期6-13,共8页
For on-line monitoring of welding quality, the characteristics of the arc sound signals in short circuit CO2 GMAW were analyzed in the time and frequency domains. The arc sound presents a series of ringing-like oscill... For on-line monitoring of welding quality, the characteristics of the arc sound signals in short circuit CO2 GMAW were analyzed in the time and frequency domains. The arc sound presents a series of ringing-like oscillations that occur at the end of short circuit i. e. the moment of arc re-ignition, and distributes mainly in the frequency band below 10 kHz. A concept of the arc tone channel and its equivalent electrical model were suggested, which is considered a time-dependent distributed parametric system of which the transmission properties depend upon the geometric and physical characteristics of the arc and surroundings, and is excited by the sound source results from the change of arc energy so that results in arc sound. The linear prediction coding ( LPC ) model is an estimation of the tone channel. The radial basis function ( RBF ) neural networks were built for on-line pattern recognition of the gas-lack in welding, in which the input vectors were formed with the LPC coefficients. The test results proved that the LPC model of arc sound and the RBF networks are feasible in on-line quality monitoring. 展开更多
关键词 arc sound signal analysis LPC model RBF neural network GMAW quality monitoring
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Three-dimensional forward modeling for magnetotelluric sounding by finite element method 被引量:3
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作者 童孝忠 柳建新 +3 位作者 谢维 徐凌华 郭荣文 程云涛 《Journal of Central South University》 SCIE EI CAS 2009年第1期136-142,共7页
A finite element algorithm combined with divergence condition was presented for computing three-dimensional(3D) magnetotelluric forward modeling. The finite element equation of three-dimensional magnetotelluric forwar... A finite element algorithm combined with divergence condition was presented for computing three-dimensional(3D) magnetotelluric forward modeling. The finite element equation of three-dimensional magnetotelluric forward modeling was derived from Maxwell's equations using general variation principle. The divergence condition was added forcedly to the electric field boundary value problem, which made the solution correct. The system of equation of the finite element algorithm was a large sparse, banded, symmetric, ill-conditioned, non-Hermitian complex matrix equation, which can be solved using the Bi-CGSTAB method. In order to prove correctness of the three-dimensional magnetotelluric forward algorithm, the computed results and analytic results of one-dimensional geo-electrical model were compared. In addition, the three-dimensional magnetotelluric forward algorithm is given a further evaluation by computing COMMEMI model. The forward modeling results show that the algorithm is very efficient, and it has a lot of advantages, such as the high precision, the canonical process of solving problem, meeting the internal boundary condition automatically and adapting to all kinds of distribution of multi-substances. 展开更多
关键词 magnetotelluric sounding three-dimensional forward modeling finite element method general variation principle divergence condition
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A Sound Quality Objective Evaluation Method Based on Auditory Peripheral Simulation Model 被引量:1
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作者 Yinhan Gao~1,Jun Xie~2,Jie Liang~1,Xin Chang~3,Baojun Wu~2 1.Experimental Centre of Testing Science,Jilin University,Changchun 130022,P.R.China 2.College of Instrumentation & Electrical Engineering,Jilin University,Changchun 130061,P.R.China 3.Laboratory of Applications and Computations in Electromagnetics and Optics,Department of Electrical Engineering, University of Washington,WA 98195-2500,USA 《Journal of Bionic Engineering》 SCIE EI CSCD 2010年第2期199-208,共10页
Based on auditory peripheral simulation model, a new Sound Quality Objective Evaluation (SQOE) method is presented,which can be used to model and analyze the impacts of head, shoulder and other parts of human body on ... Based on auditory peripheral simulation model, a new Sound Quality Objective Evaluation (SQOE) method is presented,which can be used to model and analyze the impacts of head, shoulder and other parts of human body on sound wave trans-mission.This method employs the artificial head technique, in which the head related transfer function was taken into account tothe outer ear simulation phase.First, a bionic artificial head was designed as the outer ear model with considering the outersound field in view of theory and physical explanations.Then the auditory peripheral simulation model was built, which mimicsthe physiological functions of the human hearing, simulating the acoustic signal transfer process and conversion mechanismsfrom the free field to the peripheral auditory system.Finally, performance comparison was made between the proposed SQOEmethod and ArtemiS software, and the verifications of subjective and objective related analysis were made.Results show thatthe proposed method was economical, simple, and with good evaluation quality. 展开更多
关键词 sound quality objective evaluation auditory peripheral simulation model artificial head head related transfer function
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Three-dimensional coupled-mode model and characteristics of low-frequency sound propagation in ocean waveguide with seamount topography
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作者 Ya-Xiao Mo Chao-Jin Zhang +1 位作者 Li-Cheng Lu Sheng-Ming Guo 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第8期453-462,共10页
Large-scale topography, such as a seamount, substantially impacts low-frequency sound propagation in an ocean waveguide, limiting the application of low-frequency acoustic detecting techniques. A three-dimensional(3D)... Large-scale topography, such as a seamount, substantially impacts low-frequency sound propagation in an ocean waveguide, limiting the application of low-frequency acoustic detecting techniques. A three-dimensional(3D) coupledmode model is developed to calculate the acoustic field in an ocean waveguide with seamount topography and analyze the3D effect. In this model, a correction is introduced in the bottom boundary, theoretically making the acoustic field satisfy the energy conservation. Furthermore, a large azimuth angle calculation range is obtained by using the operator theory and higher-order Pade approximation. Additionally, the model has advantages related to the coupling mode and parabolic equation theory. The couplings corresponding to the effects of range-dependent environment are fully considered, and the numerical implementation is kept feasible. After verifying the accuracy and reliability of the model, low-frequency sound propagation characteristics in the seamount environment are analyzed. The results indicate lateral variability in bathymetry can lead to out-of-plane effects such as the horizontal refraction phenomenon, while the coupling effect tends to restore the abnormal sound field and produces acoustic field diffraction behind the seamount. This model effectively considers the effects of the horizontal refraction and coupling, which are proportional to the scale of the seamount. 展开更多
关键词 coupled-mode model three-dimensional sound propagation seamount topography horizontal interference structure
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Properties of the phase diagram from the Nambu-Jona-Lasino model with a scalar-vector interaction
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作者 Yong-Hang Yang He Liu Peng-Cheng Chu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第10期168-179,共12页
We investigated the properties of the phase diagram of high-order susceptibilities,speed of sound,and polytropic index based on an extended Nambu-Jona-Lasinio model with an eight-quark scalar-vector interaction.Non-mo... We investigated the properties of the phase diagram of high-order susceptibilities,speed of sound,and polytropic index based on an extended Nambu-Jona-Lasinio model with an eight-quark scalar-vector interaction.Non-monotonic behavior was observed in all these quantities around the phase transition boundary,which also revealed the properties of the critical point.Further,this study indicated that the chiral phase transition boundary and critical point could vary depending on the scalarvector coupling constant G_(SV).At finite densities and temperatures,the negative G_(SV)term exhibited attractive interactions,which enhanced the critical point temperature and reduced the chemical potential.The G_(SV)term also affected the properties of the high-order susceptibilities,speed of sound,and polytropic index near the critical point.The non-monotonic(peak or dip)structures of these quantities shifted to a low baryon chemical potential(and high temperature)with a negative G_(SV).G_(SV)also changed the amplitude and range of the nonmonotonic regions.Therefore,the scalar-vector interaction was useful for locating the phase boundary and critical point in QCD phase diagram by comparing the experimental data.The study of the non-monotonic behavior of high-order susceptibilities,speed of sound,and polytropic index is of great interest,and further observations related to high-order susceptibilities,speed of sound,and polytropic index being found and applied to the search for critical points in heavy-ion collisions and the study of compact stars are eagerly awaited. 展开更多
关键词 QCD phase diagram High-order susceptibilities Speed of sound Polytropic index NJL model
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Fine Sand and Clay Sediment Acoustic Properties of the Novel Sediment Sample from the Arabian Sea:Experimental Investigations and Biot−Stoll Model Validation
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作者 Shahabuddin SHAIKH HUANG Yi-wang +1 位作者 ZHANG Ze-chuan Habib Hussain ZUBERI 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期169-180,共12页
The present study explores the physical and acoustic characteristics of fine sand and clay in novel seabed marine sediments from of Pakistan coastline of the Arabian Sea.The measured physical parameters included mean ... The present study explores the physical and acoustic characteristics of fine sand and clay in novel seabed marine sediments from of Pakistan coastline of the Arabian Sea.The measured physical parameters included mean grain size,mass density,bulk density,salinity,porosity,permeability,pore size and mineralogical composition.Acoustic properties,including sound speed and attenuation,in the high frequency range of 90-170 kHz were analyzed.A controlled laboratory setup with the acoustic transmission method and Fourier transform techniques was utilized to examine the sound propagation and absorption of novel seabed sediments.The standard deviation of mean sound speed in fresh water was 0.75 m/s,and attenuation was observed in the range of 0.43 to 0.61 dB/m.The mean sound velocity in sand and clay varied from 1706 to 1709 m/s and 1602 to 1608 m/s,respectively.Corresponding average attenuation was observed at 80 to 93 dB/m in sandy sediments and from 31.8 to 38.6 dB/m in clayey sediments.Sound velocity variation within sandy sediment is low,consistent with expected results,and smaller than the predicted uncertainty.However,clay sediment exhibited a positive linear correlation and low sound speed variation.Attenuation increased linearly with frequency for both sediments.Finally,the laboratory results were validated by using the Biot−Stoll model.The dispersion of sound speed in sandy and clayey sediments was consistent with the predictions of the Biot−Stoll model.Measured attenuation aligned more with Biot−Stoll model predictions due to improved permeability,tortuosity and pore size parameter fitting. 展开更多
关键词 physical and acoustic characteristics marine sediments sound speed ATTENUATION Biot−Stoll model
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Aerodynamic Sound and Flow Field Generated from Combinational Inclined Tapered Cylinder
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作者 Kohei Sato Ryutaro Machida Toshiyuki Aoki 《Open Journal of Fluid Dynamics》 2012年第4期222-227,共6页
This study deals with the aerodynamic sound, especially the Aeolian tone. One of the problems with the aerodynamic sound, noise reduction along a railway line is significant engineering issue for further speed-up of a... This study deals with the aerodynamic sound, especially the Aeolian tone. One of the problems with the aerodynamic sound, noise reduction along a railway line is significant engineering issue for further speed-up of a high-speed train. In particular, a pantograph is one of the main aerodynamic noise sources of a high-speed train. As one of the methods for the aerodynamic noise reduction, this study proposes the tapered cylinder by a pantograph. In this paper, the aerodynamic sound and the wake flow of the combinational inclined circular cylinder and tapered cylinder are experimentally and numerically investigated in knuckle upstream and knuckle downstream. Also, we suggest that the surface of grooves such as wood grain interacts with the aerodynamic sound generated from the model. Here, it is considered that the comparison of aerodynamic sound between the model with grooves and without grooves. Consequently, reduction of the maximum aerodynamic sound is possible for the tapered cylinder in the case of knuckle downstream. Furthermore, the noise reduction method is effective that the model surface with grooves such as wood grain. 展开更多
关键词 Aerodynamic sound Aeolian tone Inclined Tapered CYLINDER FLOW FIELD
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Advanced Deterioration Diagnosis Model for Building External Wall Tiles
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作者 Sy-Jye Guo 《World Journal of Engineering and Technology》 2018年第2期1-12,共12页
In 1981 Taiwan entered a period of intense construction, meaning that today many buildings are more than 30 years old. Lack of maintenance has led to frequent safety incidents involving external walls. This study focu... In 1981 Taiwan entered a period of intense construction, meaning that today many buildings are more than 30 years old. Lack of maintenance has led to frequent safety incidents involving external walls. This study focuses on a deterioration diagnostic model for external wall tiles of aged buildings, using both stage 1 and stage 2 diagnostic methods. The visual test results are categorized based on impact on public safety, and renovation strategies are proposed. Stage 1 diagnosis mainly adopted the DER visual inspection deterioration assessment method. For enhance the accuracy, this research adopted the Infrared Thermal Imaging detection method to double confirm the visual inspection results. After producing an external wall tile Condition Indicator (CI). For stage 1 diagnostic results that fall in a gray area, stage 2 diagnosis was carried out using a tap tone test, followed by fast Fourier transform and pattern recognition to analyze the tapping results. Finally, the study provides a deterioration evaluation criteria for external wall tiles replacement recommendations and a standard operating procedure for deterioration diagnosis. The study also recommends directions for future amendment of regulations, and provides a basis of reference for the government in determining urban renewal, renovation and maintenance strategies. 展开更多
关键词 DER model TAP tone METHOD Infrared Thermal Imaging METHOD BUILDING EXTERNAL Wall Tiles
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Short-Term Sinusoidal Modeling of an Oriental Music Signal by Using CQT Transform
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作者 Lhoucine Bahatti Mimoun Zazoui +1 位作者 Omar Bouattane Ahmed Rebbani 《Journal of Signal and Information Processing》 2013年第1期51-56,共6页
In this paper, we propose a method for characterizing a musical signal by extracting a set of harmonic descriptors reflecting the maximum information contained in this signal. We focus our study on a signal of orienta... In this paper, we propose a method for characterizing a musical signal by extracting a set of harmonic descriptors reflecting the maximum information contained in this signal. We focus our study on a signal of oriental music characterized by its richness in tone that can be extended to 1/4 tone, taking into account the frequency and time characteristics of this type of music. To do so, the original signal is slotted and analyzed on a window of short duration. This signal is viewed as the result of a combined modulation of amplitude and frequency. For this result, we apply short-term the non-stationary sinusoidal modeling technique. In each segment, the signal is represented by a set of sinusoids characterized by their intrinsic parameters: amplitudes, frequencies and phases. The modeling approach adopted is closely related to the slot window;therefore great importance is devoted to the study and the choice of the kind of the window and its width. It must be of variable length in order to get better results in the practical implementation of our method. For this purpose, evaluation tests were carried out by synthesizing the signal from the estimated parameters. Interesting results have been identified concerning the comparison of the synthesized signal with the original signal. 展开更多
关键词 ORIENTAL Music Signal Short Time FOURIER TRANSFORM Constant Q TRANSFORM Modulation Sinusoidal modeling Weighting Window 1/4 tone
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Towards 6G: Paradigm of Realistic Terahertz Channel Modeling 被引量:8
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作者 Ke Guan Haofan Yi +2 位作者 Danping He Bo Ai Zhangdui Zhong 《China Communications》 SCIE CSCD 2021年第5期1-18,共18页
Terahertz(THz)communications are envisioned as a key technology for the sixth-generation wireless communication system(6G).However,it is not practical to perform large-scale channel measurements with high degrees of f... Terahertz(THz)communications are envisioned as a key technology for the sixth-generation wireless communication system(6G).However,it is not practical to perform large-scale channel measurements with high degrees of freedom at THz frequency band.This makes empirical or stochastic modeling approaches relying on measurements no longer stand.In order to break through the bottleneck of scarce fulldimensional channel sounding measurements,this paper presents a novel paradigm for THz channel modeling towards 6G.With the core of high-performance ray tracing(RT),the presented paradigm requires merely quite limited channel sounding to calibrate the geometry and material electromagnetic(EM)properties of the three-dimensional(3D)environment model in the target scenarios.Then,through extensive RT simulations,the parameters extracted from RT simulations can be fed into either ray-based novel stochastic channel models or cluster-based standard channel model families.Verified by RT simulations,these models can generate realistic channels that are valuable for the design and evaluation of THz systems.Representing two ends of 6G THz use cases from microscopy to macroscopy,case studies are made for close-proximity communications,wireless connections on a desktop,and smart rail mobility,respectively.Last but not least,new concerns on channel modeling resulting from distinguishing features of THz wave are discussed regarding propagation,antenna array,and device aspects,respectively. 展开更多
关键词 channel modeling channel sounding RAYTRACING THz communication 6G
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NUMERICAL SIMULATION OF SOUND RADIATION ON GEARBOX'S HOUSING 被引量:1
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作者 XIANG Changle WANG Wenping LIU Hui 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第3期26-30,共5页
The fluid-structure coupling finite element model and the boundary element model of a complex gearbox's housing are built based on the theory of fluid-structure coupling finite element method and boundary element met... The fluid-structure coupling finite element model and the boundary element model of a complex gearbox's housing are built based on the theory of fluid-structure coupling finite element method and boundary element method. At the same time, the exciting forces of the housing are analyzed and applied to the finite element models. Firstly, vibration of the housing is calculated by the fluid-structure coupling finite element model; secondly, the calculated result is verified by the experiment; finally, sound radiation of the housing is calculated by the boundary element. According to the calculated results, the housing adds some ribs not only to increase the strength, but also to reduce the sound radiation of the housing. At last, the sound radiation of the modified housing is calculated, which shows that the sound radiation of the modified housing with ribs is lower. 展开更多
关键词 sound radiation Finite element model Boundary element model Fluid-structure coupling
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Unleashing the Power of Information Theory: Enhancing Accuracy in Modeling Physical Phenomena 被引量:1
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作者 Boris Menin 《Journal of Applied Mathematics and Physics》 2023年第3期760-779,共20页
When building a model of a physical phenomenon or process, scientists face an inevitable compromise between the simplicity of the model (qualitative-quantitative set of variables) and its accuracy. For hundreds of yea... When building a model of a physical phenomenon or process, scientists face an inevitable compromise between the simplicity of the model (qualitative-quantitative set of variables) and its accuracy. For hundreds of years, the visual simplicity of a law testified to the genius and depth of the physical thinking of the scientist who proposed it. Currently, the desire for a deeper physical understanding of the surrounding world and newly discovered physical phenomena motivates researchers to increase the number of variables considered in a model. This direction leads to an increased probability of choosing an inaccurate or even erroneous model. This study describes a method for estimating the limit of measurement accuracy, taking into account the stage of model building in terms of storage, transmission, processing and use of information by the observer. This limit, due to the finite amount of information stored in the model, allows you to select the optimal number of variables for the best reproduction of the observed object and calculate the exact values of the threshold discrepancy between the model and the phenomenon under study in measurement theory. We consider two examples: measurement of the speed of sound and measurement of physical constants. 展开更多
关键词 Finite Information Quantity International System of Units modelLING Physical Constant Speed of sound
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The measuring method of early lateral energy fraction in the scale model experiments
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作者 NI Qiyu~1, FANG Yuan~2, WU Qixue~2, SUN Guangrong~2 (1. Yangzhou University, Yangzhou 225002, China 2. Institute of Acoustics, Nanjing University, Nanjing 210093,China) 《声学技术》 CSCD 2004年第S1期49-52,共4页
This paper introduces a measuring method of early lateral energy fraction in the scale model experiments. According to the interference principle of half wave length making the high frequency figure-8 directional micr... This paper introduces a measuring method of early lateral energy fraction in the scale model experiments. According to the interference principle of half wave length making the high frequency figure-8 directional microphone. With the signal-processing technique, a receiving and analyzing system, for the measurements of lateral energy fraction in the scale model is realized. 展开更多
关键词 ROOM ACOUSTICS scale model experiment EARLY LATERAL REFLECTIVE sound
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