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Relationships between Pathological Patterns and Vocal Qualities Estimated by Acoustic Parameters 被引量:1
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作者 Young-Jae Park Young-Bae Park 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2015年第5期346-354,共9页
Objective: To examine whether vocal characteristics estimated by acoustic parameters were associated with phlegm, yin deficiency, or cold-heat patterns. Methods: A total of 75 college students (males:females = 53... Objective: To examine whether vocal characteristics estimated by acoustic parameters were associated with phlegm, yin deficiency, or cold-heat patterns. Methods: A total of 75 college students (males:females = 53:22) aged 19-24 years were enrolled in this study. Each subject was asked to complete the phlegm pattern questionnaire (PPQ), yin deficiency questionnaire (YDQ) and cold-heat questionnaire (CHQ). For the acoustic analysis, each subject was asked to produce a sustained vowel sound (/a/) for 3 s to be used to calculate acoustic parameters. Then, habitual fundamental frequency (F0), jitter, shimmer, F0 tremor, mean F0, standard deviation of F0, maximum F0, minimum F0, normalized noise energy, harmonic-to-noise ratio, signal-to-noise ratio, amplitude tremor, and power ratio were calculated using the Dr. Speech software. Finally, four hierarchical regression models with pattern questionnaire scores as dependent variables were formed to examine which factors among acoustic parameters, sex, and age were predictive of those pattern scores. Results: PPQ, YDQ, heat, and cold pattern scores all formed significant regression model equations and the adjusted R2 values were 0.281, 0.164, 0.156, and 0.170, respectively. There were aging effects in the PPQ and YDQ models (standardized β =0.199, 0.271, respectively). Vocal tremor-related Fo tremor and vocal ringing-related power ratio parameters were associated with PPQ and YDQ scores. Gender was directly predictive of PPQ and indirectly moderated the relationship between power ratio and YDQ score. Vocal pitch- related habitual F0 and mean F0 were associated with heat and cold scores. These results indicate that the vocal qualities of phlegm- and yin deficiency-susceptible subjects tend to be ringing and less tremorous, and those of heat- and cold-susceptible subjects tend to be high-pitched. Conclusion: Our study results suggest that vocal characteristics estimated by acoustic parameters are partially predictive of phlegm, yin deficiency, heat, and cold patterns. In terms of phlegm and yin deficiency patterns, there were direct or moderating effects of sex and age. 展开更多
关键词 Chinese medicine syndrome oriental medicine acoustic parameters
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Molecular structure dependence of acoustic nonlinearity parameter B/A for silicone oils
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作者 张喆 陈功 章东 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第5期333-338,共6页
Exploring new acoustic parameters is essential to develop a noninvasive imaging technique for the surgery of silicone oil tamponades. In this study, the acoustic nonlinearity parameters B/A of varied silicone oil samp... Exploring new acoustic parameters is essential to develop a noninvasive imaging technique for the surgery of silicone oil tamponades. In this study, the acoustic nonlinearity parameters B/A of varied silicone oil samples (e.g., linear or hyper-branched) are experimentally measured by using a modified thermodynamic method. The results show that: (i) when the concentration of the silicone oil with a molecular weight of 5 × 10^4 increases from 0.5 g/100 ml to 8 g/100 ml, the corresponding B/A value increases by about 18%, but the acoustic velocity only increases by about 0.1%; (ii) when the molecular weight of the hyper-branched silicone oil is enhanced from 2 × 10^5 to 1 × 10^6, the B/A value increases by about 22%, while the acoustic velocity is only raised by about 0.2%. This study suggests that the B/A parameter of the silicone oil is more sensitive to the change in its molecular structure than that of the acoustic velocity. Thus, the B/A parameter might be utilized as an effective index for the development and optimization of the noninvasive imaging of the surgery of silicone oil tamponades. 展开更多
关键词 acoustic nonlinearity parameter molecular structure modified thermodynamic method siliconeoil
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Investigation of acoustic attributes based on preference and perceptional acoustics of Korean traditional halls for optimal design solutions
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作者 Beta Bayu Santika Haram Lee Jin Yong Jeon 《Building Simulation》 SCIE EI CSCD 2024年第5期723-738,共16页
Immersed in the rich tapestry of traditional culture,Gugak,the traditional Korean music stands as a captivating embodiment of artistic expression.This study embarked on a comprehensive evaluation of a Gugak hall,emplo... Immersed in the rich tapestry of traditional culture,Gugak,the traditional Korean music stands as a captivating embodiment of artistic expression.This study embarked on a comprehensive evaluation of a Gugak hall,employing acoustic measurements,computer simulations,and subjective perception surveys.The evaluation focused on the reverberance,clarity,spatial impression,and preference,unravelling the secrets that shape the immersive Gugak experience.Through intricate computer simulations and auralization,the experience of Gugak performances was meticulously brought to life,allowing exploration under diverse conditions by adjusting stage volume ratios from -20% to+20% and modifying the interior materials,including the walls,ceiling,and lateral reflectors.Although Gugak halls exhibited relatively low values of reverberation time(RT),early decay time(EDT),and binaural quality index(BQI)the dominant factor influencing the acoustic environment was the effect of sound strength(G).Musical clarity(C80)value did not show an inverse proportionality to the reverberation time.Furthermore,genre differences between traditional Korean and Western classical music did not significantly affect listeners’perception and satisfaction with regards to reverberance,clarity,and spatial impression.As a result,Gugak halls can adhere to the same acoustic design criteria as Western orchestra halls,since this study found that people perceived them the same way.In this study,sound strength was found to be strongly correlated with perception indicators.It was possible to enhance listeners’perception and preference regarding the acoustic environment through material and structural changes to the sidewalls and ceiling.These changes improved the reinforcement of low frequencies and simultaneously enhanced the relative effect of side reflections.Additionally,enhancing the reflection and spatial characteristics of the materials effectively improved listener preference.Based on these findings,an optimal design solution was proposed. 展开更多
关键词 Korean traditional hall acoustical parameters perceptual evaluation acoustic preference stage volume ratio
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Advertisement Call Variability in the Black-spined Toad Bufo melanostictus (Anura: Bufonidae) during the Breeding Season in Lishui, Zhejiang, China 被引量:7
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作者 Li WEI Lihua ZHAO +3 位作者 Xiaohao MA Xiaoli FAN Xiaomei MA Zhihua LIN 《Asian Herpetological Research》 SCIE 2012年第2期157-162,共6页
Advertisement calls play an important role in influencing female mate choice and are regarded as one of the key characters responsible for reproductive isolation and speciation events in frogs and toads. The black-spi... Advertisement calls play an important role in influencing female mate choice and are regarded as one of the key characters responsible for reproductive isolation and speciation events in frogs and toads. The black-spined toad, Bufo melanostictus, is one of the most common amphibians in Southeast Asia and is frequently observed in human habitations throughout its distributional range. The advertisement calls of the toad have not been well described. Here, we report the advertisement calls of this species from Lishui, Zhejiang, China during its breeding season. The advertisement calls of B. melanostictus are composed of single notes with a single harmonic frequency emitted sporadically. The call parameters recorded in this study were highly variable across recording times and with different body sizes. Dominant frequency was negatively correlated with body size. Comparing the calls of the B. melanostictus population from Lishui with the populations from five other localities(Bangkok, Thailand; Coorg, India; Burma, Myanmar; Bali, Indonesia; Halimun-Salak National Park, Indonesia), we found that call structure was similar among five different populations with no harmonics, while the Halimun-Salak National Park population contained two clear harmonics. Dominant frequency was similar between Bali(1.56 kHz) and Coorg(1.6 kHz) populations, while it was highly variable among other populations. Besides call duration, call interval and pulse/call rate may also be significantly different among the comparing populations. Pooling the available data, we observed some similarities and differences in call parameters among the six populations. 展开更多
关键词 ANURA VOCALIZATION Bufo melanostictus acoustic parameters advertisement call artificial pond
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ADCP measurements of suspended sediment flux at the entrance to Jiaozhou Bay, western Yellow Sea 被引量:2
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作者 WANG Yaping GAO Shu 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2013年第12期96-103,共8页
The purpose of the present contribution is to explore the technique to use Acoustic Doppler Current Pro- filers (ADCPs) for suspended sediment flux measurements, which may be applied to coastal embayment environment... The purpose of the present contribution is to explore the technique to use Acoustic Doppler Current Pro- filers (ADCPs) for suspended sediment flux measurements, which may be applied to coastal embayment environments such as estuaries and tidal inlets for sediment exchange and budget studies. Based on tidal cycle measurements from the entrance of ]iaozhou Bay, Shandong Peninsula, eastern China, statistical rela- tionships between the suspended sediment concentration (SSC) and ADCP echo intensity output are estab- lished. Echo intensity data obtained during an ADCP survey along two cross-sections during a spring tidal phase were transformed into SSC data. The ADCP current velocity and SSC data were then used to calculate the flux of fine-grained sediment. The results show that net sediment transport at the entrance is directed towards the open sea, with an order of magnitude of 103 t per spring tidal cycle; hence, although Jiaozhou Bay is a low SSC environment, the tidally induced suspended sediment transport can be intense. 展开更多
关键词 ADCP suspended sediment concentration grain size acoustic parameters Jiaozhou Bay
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Acquisition of pronunciation of consonant clusters by Arabic speakers of English as a second language
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作者 Seetha Jayaraman 《Sino-US English Teaching》 2010年第1期46-56,共11页
The study is based on an observation of the pronunciation of a group of undergraduate students of English as a Second Language (ESL) whose mother tongue is Arabic and who have no formal training in the spoken variet... The study is based on an observation of the pronunciation of a group of undergraduate students of English as a Second Language (ESL) whose mother tongue is Arabic and who have no formal training in the spoken variety of English other than that received in the classroom. The study of acquisition of pronunciation of consonant clusters at morphological, particularly at the morphophonological levels indicates that the learners are sensitive to the syllabic structure viz., cccv type and cccvcc type, at the word-initial, medial and final positions. Samples of words with different consonant clusters were tested with a homogeneous group of students. Words of identical morphological categories were used as the data to test the students' level of perception. These were analyzed using Speech Analyzer Version 2.5. The data includes consonant clusters like plosive-fricative, plosive-plosive, fricative-fricative and plosive-fricative-trill/liquid combinations. The results varied according to the perceptual and articulatory abilities of the learners. It was observed that the plosive perception and acquisition of three-consonant clusters of plosive-plosive word initially, plosive-plosive combinations word finally and plosive-fricative type, posed more difficulty for the learners. The tendency to drop one of the consonants of the cluster was more pronounced with syllables ending in plural morphemes and those ending in -mp, -pt, -kt, -nt, -bt, etc. Difficulty was also noticed with the initial plosive+/r/, plosive+/1/combinations, especially in word initial positions. Across the syllable boundaries, these clusters are almost inaudible with some speakers. The difficulty in the articulation of these consonant clusters can be accounted for the mother tongue influence, as in the case of many other features. The results of the analysis have a pedagogical implication in the use of such words with consonant clusters, to teach reading skills to the students of undergraduate level in the present setting and promote self-learning through the use of speech tools. 展开更多
关键词 consonant clusters acoustic parameters DURATION INTELLIGIBILITY spectrograms
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Ultrasonic characterization of porcine liver tissue at frequency between 25 to 55 MHz 被引量:1
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作者 Xiao-Zhou Liu Xiu-Fen Gong +2 位作者 Dong Zhang Shi-Gong Ye Bing Rui 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第14期2276-2279,共4页
AIM: To study the relation between acoustic parameters and histological structure of biological tissue and to provide the basis for high-resolution image of biological tissues and quantitative ultrasonic diagnosis of... AIM: To study the relation between acoustic parameters and histological structure of biological tissue and to provide the basis for high-resolution image of biological tissues and quantitative ultrasonic diagnosis of liver disease. METHODS: Ultrasonic imaging and tissue characterization of four normal porcine liver and five cirrhotic liver tissue samples were performed using a high frequency imaging system. RESULTS: The acoustic parameters of cirrhotic liver tissue were larger than those of normal liver tissue. The sound velocity was 1577 m/s in normal liver tissue and 1631 m/s in cirrhotic liver tissue. At 35 MHz, the attenuation coefficient was 3.0 dB/mm in normal liver tissue and 4.1 dB/mm in cirrhotic liver tissue. The backscatter coefficient was 0.00431 dB/Srmm in cirrhotic liver tissue and 0.00303 dB/Srmm in normal liver tissue. The backscatter coefficient increased with the frequency. The high frequency images coincided with their histological features. CONCLUSION: The acoustic parameters, especially the sound backscatter coefficient, are sensitive to the changes of liver tissues and can be used to differentiate between the normal and pathological liver tissues. High frequency image system is a useful device for highresolution image and tissue characterization. 展开更多
关键词 Porcine liver tissue Hepatocirrhosis High frequency imaging Tissue characterization acoustic parameter
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Studies on Thermodynamic Properties of Some Imidazolinone Derivatives in DMF at 308.15 K 被引量:1
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作者 Shipra Baluja Asif Solanki Nikunj Kachhadia 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第2期306-311,共6页
Density,ultrasonic velocity and viscosity of imidazolinone derivatives are studied in dimethyl formamide(DMF) at 308.15 K.From the experimental data,various acoustical parameters,such as specific impedance Z,isentropi... Density,ultrasonic velocity and viscosity of imidazolinone derivatives are studied in dimethyl formamide(DMF) at 308.15 K.From the experimental data,various acoustical parameters,such as specific impedance Z,isentropic compressibilityκs,Rao's molar sound function Rm,van der Waals constant b,relaxation strength r,intermolecular free length Lf,internal pressureπ,solvation number Sn,relative association RA,etc.are evaluated,which helps in understanding the molecular interactions occurring in these solutions. 展开更多
关键词 imidazolinone derivatives ultrasonic study acoustical parameters dimethyl formamide
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Ultrasonic study on organic liquid and binary organic liquid mixtures by using Schaaffs' collision factor theory 被引量:1
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作者 卢义刚 董彦武 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第9期2030-2035,共6页
Based on Schaaff's collision factor theory (CFT) in liquids, the equations for nonlinear ultrasonic parameters in both organic liquid and binary organic liquid mixtures are deduced. The nonlinear ultrasonic paramet... Based on Schaaff's collision factor theory (CFT) in liquids, the equations for nonlinear ultrasonic parameters in both organic liquid and binary organic liquid mixtures are deduced. The nonlinear ultrasonic parameters, including pressure coefficient, temperature coefficients of ultrasonic velocity, and nonlinear acoustic parameter B/A in both organic liquid and binary organic liquid mixtures, are evaluated for comparison with the measured results and data from other sources. The equations show that the coefficient of ultrasonic velocity and nonlinear acoustic parameter B/A are closely related to molecular interactions. These nonlinear ultrasonic parameters reflect some information of internal structure and outside status of the medium or mixtures. From the exponent of repulsive forces of the molecules, several thermodynamic parameters, pressure and temperature of the medium, the nonlinear ultrasonic parameters and ultrasonic nature of the medium can be evaluated. When evaluating and studying nonlinear acoustic parameter B/A of binary organic liquid mixtures, there is no need to know the nonlinear acoustic parameter B/A of the components. Obviously, the equation reveals the connection between the nonlinear ultrasonic nature and internal structure and outside status of the mixtures more directly and distinctly than traditional mixture law for B/A, e.g. Apfel's and Sehgal's laws for liquid binary mixtures. 展开更多
关键词 nonlinear acoustic parameter B/A coefficient of ultrasonic velocity organic liquid binary organic liquid mixtures
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An experimental study on fracture mechanical behavior of rock-like materials containing two unparallel fissures under uniaxial compression 被引量:9
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作者 Yan-Hua Huang Sheng-Qi Yang +2 位作者 Wen-Ling Tian Wei Zeng Li-Yuan Yu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2016年第3期442-455,共14页
Strength and deformability characteristics of rock with pre-existing fissures are governed by cracking behavior. To further research the effects of pre-existing fissures on the mechanical properties and crack coalesce... Strength and deformability characteristics of rock with pre-existing fissures are governed by cracking behavior. To further research the effects of pre-existing fissures on the mechanical properties and crack coalescence process, a series of uniaxial compression tests were carried out for rock-like material with two unparallel fissures.In the present study, cement, quartz sand, and water were used to fabricate a kind of brittle rock-like material cylindrical model specimen. The mechanical properties of rock-like material specimen used in this research were all in good agreement with the brittle rock materials. Two unparallel fissures(a horizontal fissure and an inclined fissure) were created by inserting steel during molding the model specimen.Then all the pre-fissured rock-like specimens were tested under uniaxial compression by a rock mechanics servocontrolled testing system. The peak strength and Young's modulus of pre-fissured specimen all first decreased and then increased when the fissure angle increased from 0?to 75?.In order to investigate the crack initiation, propagation and coalescence process, photographic monitoring was adopted to capture images during the entire deformation process.Moreover, acoustic emission(AE) monitoring technique was also used to obtain the AE evolution characteristic of prefissured specimen. The relationship between axial stress, AE events, and the crack coalescence process was set up: when a new crack was initiated or a crack coalescence occurred, thecorresponding axial stress dropped in the axial stress–time curve and a big AE event could be observed simultaneously.Finally, the mechanism of crack propagation under microscopic observation was discussed. These experimental results are expected to increase the understanding of the strength failure behavior and the cracking mechanism of rock containing unparallel fissures. 展开更多
关键词 Rock-like material Two unparallel fissures Mechanical parameters Crack evolution acoustic emission(AE)
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Professor Beranek's criteria about Acoustical parameters in concert hall acoustics 被引量:1
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作者 LIU Ke ZHOU Qijun(Institute of Acoustics, The Chinese Academy of Sciences Beijing 100080) 《Chinese Journal of Acoustics》 2003年第2期121-131,共11页
Professor Beranek talked about the sound qualities of concert hall. The 58 famous concert halls in the world were graded according to the subjective comparison from the professional musicians and music lovers. Six mea... Professor Beranek talked about the sound qualities of concert hall. The 58 famous concert halls in the world were graded according to the subjective comparison from the professional musicians and music lovers. Six measurable objective parameters were proposed. The ranking according to these parameters were presented. 展开更多
关键词 in on IT HALL Professor Beranek’s criteria about acoustical parameters in concert hall acoustics IS of
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Effects of sediment parameters on the low frequency acoustic wave propagation in shallow water 被引量:5
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作者 LI Zhenglin WANG Yaojun(The State Key Laboratory of Modern Acoustics, Nanjing University Nanjing 210093)MA Li GAO Tianfu(Institute of Acoustics, Academia Silica Beijing 100080) 《Chinese Journal of Acoustics》 2000年第3期221-229,共9页
The integral expression for acoustic field due to a point source in shallow waterwhile sediment is either a liquid or a solid is derived. The synthetic full waveforms are simulatedusing real axis integration and FFF m... The integral expression for acoustic field due to a point source in shallow waterwhile sediment is either a liquid or a solid is derived. The synthetic full waveforms are simulatedusing real axis integration and FFF method. The effects of the seabed sediment parametersand center frequency of the source on the low frequency acoustic wave propagation in shallowwater are investigated. The conclusion is that the wave groups received in far field are thoseof the mode waves of the source center frequency. The possibility for inversely deducing thecompressional and shear sound speeds of sediment using the least square optimum through themeasured group velocities of a selected mode at different frequencies is discussed. 展开更多
关键词 WAVE Effects of sediment parameters on the low frequency acoustic wave propagation in shallow water
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Numerical analysis of the 2D acoustic field with fuzzy-random parameters 被引量:2
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作者 CHEN Ning YU Dejie +1 位作者 XIA Baizhan L Hui 《Chinese Journal of Acoustics》 2014年第4期391-405,共15页
Regard for the fuzziness and the randomness in some acoustic fields,a method for the numerical analysis of the 2D acoustic field with Fuzzy-Random parameters was proposed based on the equivalent conversion of informat... Regard for the fuzziness and the randomness in some acoustic fields,a method for the numerical analysis of the 2D acoustic field with Fuzzy-Random parameters was proposed based on the equivalent conversion of information entropy.In the proposed method,a fuzzyrandom acoustic field was treated as a pure fuzzy acoustic field or a pure random acoustic field by transforming all the variables into fuzzy variables or random variables.Perturbation finite element methods for analyzing the two-dimensional acoustic fuzzy and random field are deduced.The sound pressure response of a 2D acoustic tube and the 2D acoustic cavity of a car with fuzzy-random parameters were analyzed by the proposed method and the Monte Carlo method,the results show that the proposed method can be well applied to the numerical analysis of the 2D acoustic field with fuzzy-random parameters,and has good prospect of engineering application. 展开更多
关键词 Numerical analysis of the 2D acoustic field with fuzzy-random parameters
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Acoustic Nonlinearity Parameters Due to Microstructural Defects
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作者 Xiang Gao Jianmin Qu 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2018年第5期525-534,共10页
This study presents a general approach to derive the acoustic nonlinearity parameters induced by various types of dislocation configurations including dislocation strings (monopoles), dislocation dipoles, dislocatio... This study presents a general approach to derive the acoustic nonlinearity parameters induced by various types of dislocation configurations including dislocation strings (monopoles), dislocation dipoles, dislocation pileups and extended dislocations. It is found that expressions of the acoustic nonlinearity parameter induced by such a variety of dislocation con- figurations share a common mathematical form. They are all scaled with (Lch/b)n, where Lch is a characteristic length of the dislocation configuration, b is the magnitude of the Burgers vector, and n is either 3 or 4. Semiquantitative analysis is presented to compare the magnitudes of the acoustic nonlinearity parameters among different types of dislocation configurations. 展开更多
关键词 Nonlinear ultrasound Nondestructive evaluation acoustic nonlinearity parameter Microstructural defects Dislocations
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Estimation of boundary parameters and prediction of transmission loss based upon ray acoustics 被引量:1
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作者 GUO Yuhong FAN Minyi HUI Junying (Harbin Engineering University Harbin 150001) 《Chinese Journal of Acoustics》 2000年第4期371-376,共6页
Estimation of boundary parameters and prediction of transmission loss using a coherent channel model based upon ray acoustics and sound propagation data collected in field experiments are presented. Comparison betwee... Estimation of boundary parameters and prediction of transmission loss using a coherent channel model based upon ray acoustics and sound propagation data collected in field experiments are presented. Comparison between the prediction results and the experiment data indicates that the adopted sound propagation model is valuable, both selection and estimation methods on boundary parameters are reasonable, and the prediction performance of transmission loss is favorable. 展开更多
关键词 Estimation of boundary parameters and prediction of transmission loss based upon ray acoustics
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A semi-analytical method to compute acoustic nonlinearity parameter of Cu,Ag and Au
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作者 Zi-Mu Chen Zheng Zhang 《Rare Metals》 SCIE EI CAS CSCD 2023年第3期1050-1055,共6页
In this paper,a semi-analytical method was proposed to evaluate the acoustic nonlinearity parameter for single crystals of Cu,Ag and Au.The acoustic nonlinearity parameter can be derived analytically by general expres... In this paper,a semi-analytical method was proposed to evaluate the acoustic nonlinearity parameter for single crystals of Cu,Ag and Au.The acoustic nonlinearity parameter can be derived analytically by general expressions in terms of the interatomic potentials with the distances between each pair of atoms in these transition metals.To evaluate the acoustic nonlinearity parameter,one needs to conduct one step molecular static simulation and obtain the equilibrium positions of all the atoms.Further,based on this method,numerical experiments with molecular dynamic code LAMMPS were given to compute the acoustic nonlinearity parameter of Cu,Ag and Au.To illustrate the validity of these expressions,comparison was made between calculation results and data in the literature.Reasonable agreement is observed.Because of the analytical nature of this method,it provides a fundamental understanding of the nonlinear elastic behavior of these transition metals. 展开更多
关键词 Nondestructive testing SEMI-ANALYTICAL acoustic nonlinearity parameter Molecular static simulation
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Nonlinearity acoustic parameter B/A in organic liquids 被引量:1
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作者 LU Yigang FENG Jinyuan (Department of Applied Physics, South China University of Technology Guangzhou 510641) TONG Jie DONG Yanwu (Applied Acoustics Institute, Shaanxi Normal University Xi’an 710062) 《Chinese Journal of Acoustics》 2000年第3期285-288,共4页
Based on Jacobson's free length theory and the dependence of ultrasonic velocity on the free length in organic liquids, the equation of nonlinearity acoustic parameter B/A was given, and the calculated nonlinearit... Based on Jacobson's free length theory and the dependence of ultrasonic velocity on the free length in organic liquids, the equation of nonlinearity acoustic parameter B/A was given, and the calculated nonlinearity acoustic parameter B/A in some organic liquids are in good agreement with the measured results. 展开更多
关键词 Nonlinearity acoustic parameter B/A in organic liquids
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The influence of molecular structure of protein on the acoustic nonlinearity parameter B/A
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作者 LU Zhiqu GONG Xiufen +1 位作者 WANG Shiquan LIU Jiehui and ZHANG Heyun(Institute ot Acoustics, State Key Lab. of Modern Acoustics, Nanjing University Nanjing 210093)(Department of Biochemistry Nanjing University Nanjing 210093) 《Chinese Journal of Acoustics》 1996年第4期358-366,共9页
In this paper, the influence of molecular structure of proteins on the acoustic non-linearity parameter B/A has been studied. By using biochemical technique, three proteins such as bovine serum albumin, bovine hemoglo... In this paper, the influence of molecular structure of proteins on the acoustic non-linearity parameter B/A has been studied. By using biochemical technique, three proteins such as bovine serum albumin, bovine hemoglobin and pepsin were employed and their quarternary,tertiary and secondary protein structures were perturbed by the denaturing agent sodium do-decyl sulfate (SDS) solution, while their primary structures of protein were not changed. This means that only the structural features were altered and the chemical composition maintained unchanged. B/A has been measured by using improved thermodynamic method. The experi-mental results show that when the concentration of SDS solution increases, the alterations of the protein structure increase, and the contribution of protein to the B/A value decreases. Re-sults indicate that the B/A values can display the destruction of molecular structure of protein.Some explanation of these phenomena has also been made in this paper. 展开更多
关键词 acoustic nonlinearity parameter B/A Protein structure SDS solution
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Ultrasound speed and attenuation in progressive trypsin digested articular cartilage 被引量:3
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作者 NIU HaiJun LI LiFeng +4 位作者 SUN Feng YAN Yan WANG YueXiang LI DeYu FAN YuBo 《Science China(Life Sciences)》 SCIE CAS 2011年第11期1029-1035,共7页
Subtle changes of articular cartilage(AC) can lead to tissue degeneration and even osteoarthritis(OA).The early degeneration of AC is closely related to a change in proteoglycans(PG) content.The observation of PG is t... Subtle changes of articular cartilage(AC) can lead to tissue degeneration and even osteoarthritis(OA).The early degeneration of AC is closely related to a change in proteoglycans(PG) content.The observation of PG is therefore an appropriate way of studying OA and evaluating the degree of AC degeneration.In this study,20 cartilage-bone samples were prepared from normal porcine femoral condyle cartilage and 10 samples were digested over 2 h using 0.25% trypsin solution.The dynamic process of PG-digestion was explored using a conventional A-mode ultrasound(US) experimental system with a 10 MHz center frequency.Quantitative acoustic parameters were calculated from ultrasonic radio-frequency echo signals and included US speed(USS),US amplitude attenuation coefficient(UAA) and broadband US attenuation coefficient(BUA).The experimental results showed that the conventional A-mode ultrasound is valuable for tracking the degree of PG-digestion.Histology also confirmed the validity of the ultrasound observations.For every AC sample,the degree of PG-digestion within a given time was different and was affected by individual differences.After two hours of degeneration,USS showed a mean decrease of 0.4%(P<0.05).UAA was significantly lower after a two-hour PG depletion period(from(2.45±0.23) to(2.28±0.41) dB mm?1).BUA showed no significant differences during this process.In conclusion,conventional ultrasound can provide useful information about trypsin-induced progressive PG depletion in AC and can reflect variations of PG content via the quantitative acoustic parameters USS and UAA.The results of this study may be used to identify an indirect indicator of cartilage matrix integrity and OA disease progression. 展开更多
关键词 articular cartilage trypsin degeneration OSTEOARTHRITIS acoustic parameters
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Ultrasonic study of adsorption in polysaccharide (starch) metabolism
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作者 S.NITHIYANANTHAM L.PALANIAPPAN D.Raja 《Frontiers of Chemistry in China》 2011年第2期147-152,共6页
Starch metabolism due to adsorption of enzyme amylase on the starch substrate is outlined briefly.To explore the necessary conditions required for effective adsorption in biological media,ultrasonic techniques have be... Starch metabolism due to adsorption of enzyme amylase on the starch substrate is outlined briefly.To explore the necessary conditions required for effective adsorption in biological media,ultrasonic techniques have been applied to elucidate the structural variations and component destruction in the considered systems.The ability of the enzyme amylase to break the linkages in starch(substrate)was determined from the observed ultrasonic velocity,which highlights the deciding factors of metabolism.It is concluded that the phenomenon of adsorption is decided by the surface area,the number of subunits held by the substrate,and the structure existing in the adsorbent,and above all,a relatively higher quantity of enzyme and the substrate. 展开更多
关键词 acoustic parameters molecular interaction ADSORPTION STARCH
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