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Recognition System for Diagnosing Pneumonia and Bronchitis Using Children’s Breathing Sounds Based on Transfer Learning
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作者 Jianying Shi Shengchao Chen +3 位作者 Benguo Yu Yi Ren Guanjun Wang Chenyang Xue 《Intelligent Automation & Soft Computing》 SCIE 2023年第9期3235-3258,共24页
Respiratory infections in children increase the risk of fatal lung disease,making effective identification and analysis of breath sounds essential.However,most studies have focused on adults ignoring pediatric patient... Respiratory infections in children increase the risk of fatal lung disease,making effective identification and analysis of breath sounds essential.However,most studies have focused on adults ignoring pediatric patients whose lungs are more vulnerable due to an imperfect immune system,and the scarcity of medical data has limited the development of deep learning methods toward reliability and high classification accuracy.In this work,we collected three types of breath sounds from children with normal(120 recordings),bronchitis(120 recordings),and pneumonia(120 recordings)at the posterior chest position using an off-the-shelf 3M electronic stethoscope.Three features were extracted from the wavelet denoised signal:spectrogram,mel-frequency cepstral coefficients(MFCCs),and Delta MFCCs.The recog-nition model is based on transfer learning techniques and combines fine-tuned MobileNetV2 and modified ResNet50 to classify breath sounds,along with software for displaying analysis results.Extensive experiments on a real dataset demonstrate the effectiveness and superior performance of the proposed model,with average accuracy,precision,recall,specificity and F1 scores of 97.96%,97.83%,97.89%,98.89%and 0.98,respectively,achieving superior performance with a small dataset.The proposed detection system,with a high-performance model and software,can help parents perform lung screening at home and also has the potential for a vast screening of children for lung disease. 展开更多
关键词 Deep learning breath sounds transfer learning signal denoising
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Relationship between polyhedral structures formed by tangent planes of ellipsoidal particles and system sound velocity
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作者 Cheng-Bo Li Lin Bao Chuang Zhao 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期448-456,共9页
Internal polyhedral structures of a granular system can be investigated using the Voronoi tessellations.This technique has gained increasing recognition in research of kinetic properties of granular flows.For systems ... Internal polyhedral structures of a granular system can be investigated using the Voronoi tessellations.This technique has gained increasing recognition in research of kinetic properties of granular flows.For systems with mono-sized spherical particles,Voronoi tessellations can be utilized,while radial Voronoi tessellations are necessary for analyzing systems with multi-sized spherical particles.However,research about polyhedral structures of non-spherical particle systems is limited.We utilize the discrete element method to simulate a system of ellipsoidal particles,defined by the equation(x a)2+(y1)2+(z 1/a)2=1,where a ranges from 1.1 to 2.0.The system is then dissected by using tangent planes at the contact points,and the geometric quantities of the resulting polyhedra in different shaped systems,such as surface area,volume,number of vertices,number of edges,and number of faces,are calculated.Meanwhile,the longitudinal and transverse wave velocities within the system are calculated with the time-of-flight method.The results demonstrate a strong correlation between the sound velocity of the system and the geometry of the dissected polyhedra.The sound velocity of the system increases with the increase in a,peaking at a=1.3,and then decreases as a continues to increase.The average volume,surface area,number of vertices,number of edges,and number of faces of the polyhedra decrease with the increase in sound velocity.That is,these quantities initially decrease with the increase in a,reaching minima at a=1.3,and then increase with further increase of a.The relationship between sound velocity and the geometric quantities of the dissected polyhedra can serve as a reference for acoustic material design. 展开更多
关键词 discrete element method Voronoi tessellation polyhedral structure sound velocity
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A New Method for Deriving High-Vertical-Resolution Wind Vector Data from the L-Band Radar Sounding System in China
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作者 Fang YUAN Zijiang ZHOU Jie LIAO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第11期2192-2202,共11页
High-vertical-resolution radiosonde wind data are highly valuable for describing the dynamics of the meso-and microscale atmosphere. However, the current algorithm used in China's L-band radar sounding system for ... High-vertical-resolution radiosonde wind data are highly valuable for describing the dynamics of the meso-and microscale atmosphere. However, the current algorithm used in China's L-band radar sounding system for calculating highvertical-resolution wind vectors excessively smooths the data, resulting in significant underestimation of the calculated kinetic energy of gravity waves compared to similar products from other countries, which greatly limits the effective utilization of the data. To address this issue, this study proposes a novel method to calculate high-vertical-resolution wind vectors that utilizes the elevation angle, azimuth angle, and slant range from L-band radar. In order to obtain wind data with a stable quality, a two-step automatic quality control procedure, including the RMSE-F(root-mean-square error F) test and elemental consistency test are first applied to the slant range data, to eliminate continuous erroneous data caused by unstable signals or radar malfunctions. Then, a wind calculation scheme based on a sliding second-order polynomial fitting is utilized to derive the high-vertical-resolution radiosonde wind vectors. The evaluation results demonstrate that the wind data obtained through the proposed method show a high level of consistency with the high-resolution wind data observed using the Vaisala Global Positioning System and the data observed by the new Beidou Navigation Sounding System. The calculation of the kinetic energy of gravity waves in the recalculated wind data also reaches a level comparable to the Vaisala observations. 展开更多
关键词 L-band radar sounding system upper air high-vertical-resolution radiosonde wind vectors quality control polynomial fitting
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Diagnostic Accuracy of Computerized Bowel Sound Analysis with Non-Invasive Devices for Irritable Bowel Syndrome:A Systematic Review and Meta-Analysis
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作者 Xia-Xiao Yan Yue-Lun Zhang +2 位作者 Yu-Pei Zhang Ying-Yun Yang Dong Wu 《Chinese Medical Sciences Journal》 CAS CSCD 2024年第2期122-130,共9页
Objective To assess the diagnostic accuracy of bowel sound analysis for irritable bowel syndrome(IBS)with a systematic review and meta-analysis.Methods We searched MEDLINE,Embase,the Cochrane Library,Web of Science,an... Objective To assess the diagnostic accuracy of bowel sound analysis for irritable bowel syndrome(IBS)with a systematic review and meta-analysis.Methods We searched MEDLINE,Embase,the Cochrane Library,Web of Science,and IEEE Xplore databases until September 2023.Cross-sectional and case-control studies on diagnostic accuracy of bowel sound analysis for IBS were identified.We estimated the pooled sensitivity,specificity,positive likelihood ratio,negative likeli-hood ratio,and diagnostic odds ratio with a 95% confidence interval(CI),and plotted a summary receiver operat-ing characteristic curve and evaluated the area under the curve.Results Four studies were included.The pooled diagnostic sensitivity,specificity,positive likelihood ratio,nega-tive likelihood ratio,and diagnostic odds ratio were 0.94(95%CI,0.87‒0.97),0.89(95%CI,0.81‒0.94),8.43(95%CI,4.81‒14.78),0.07(95%CI,0.03‒0.15),and 118.86(95%CI,44.18‒319.75),respectively,with an area under the curve of 0.97(95%CI,0.95‒0.98).Conclusions Computerized bowel sound analysis is a promising tool for IBS.However,limited high-quality data make the results'validity and applicability questionable.There is a need for more diagnostic test accuracy studies and better wearable devices for monitoring and analysis of IBS. 展开更多
关键词 irritable bowel syndrome bowel sound analysis diagnostic accuracy systematic review META-ANALYSIS
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Sound Transmission Loss Analysis of a Double Plate-Acoustic Cavity Coupling System with In-Plane Functionally Graded Materials
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作者 Changzhong Chen Mingfei Chen Wenliang Yu 《Journal of Applied Mathematics and Physics》 2024年第6期2333-2345,共13页
In this paper, the isogeometric analysis (IGA) is employed to develop an acoustic radiation model for a double plate-acoustic cavity coupling system, with a focus on analyzing the sound transmission loss (STL). The fu... In this paper, the isogeometric analysis (IGA) is employed to develop an acoustic radiation model for a double plate-acoustic cavity coupling system, with a focus on analyzing the sound transmission loss (STL). The functionally graded (FG) plate exhibits a different material properties in-plane, and the power-law rule is adopted as the governing principle for material mixing. To validate the harmonic response and demonstrate the accuracy and convergence of the isogeometric modeling, ANASYS is utilized to compare with numerical examples. A plane wave serves as the acoustic excitation, and the Rayleigh integral is applied to discretize the radiated plate. The STL results are compared with the literature, confirming the reliability of the coupling system. Finally, the investigation is conducted to study impact of cavity depth and power-law parameter on the STL. 展开更多
关键词 Isogeometric Analysis Sound Transmission Loss Double-Plate system Functionally Graded Materials Acoustic Structure Coupling
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Field testing of the surface electromagnetic prospecting system 被引量:2
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作者 底青云 付长民 +3 位作者 安志国 许诚 王亚璐 王中兴 《Applied Geophysics》 SCIE CSCD 2017年第3期449-458,462,共11页
To test the performance of the Chinese whole-surface electromagnetic prospecting (SEP) system, system integrations, instrument performances, and large-scale production viabilities in Liaoning province and Inner Mong... To test the performance of the Chinese whole-surface electromagnetic prospecting (SEP) system, system integrations, instrument performances, and large-scale production viabilities in Liaoning province and Inner Mongolia were measured via extensive field tests. Resultant electric fields, magnetic fields, apparent resistivities, impedance phases, and inversion profiles compared favorably with results of commercial equipment from other countries. The inversion results agreed well with the geologic information from boreholes. Field tests showed that the SEP system is stable, reliable, lightweight, and easy to operate, making it suitable and ready for real-field exploration. 展开更多
关键词 ground electromagnetic instrument electromagnetic sounding system SEP CSAMT
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Audile Eyes and Imaginative Ears——Audio System in Robert Frost’s Poetry
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作者 郭文正 《海外英语》 2014年第14期181-183,共3页
Frost's poems enjoy great popularity among people worldwide. He has written a large number of poems with rich rhyme throughout his career. Frost uses metre and sound devices to reinforce the theme, giving a sense ... Frost's poems enjoy great popularity among people worldwide. He has written a large number of poems with rich rhyme throughout his career. Frost uses metre and sound devices to reinforce the theme, giving a sense of beauty, and modifying the crude reality. People love his poems, and admire him for his clever using of audio system. 展开更多
关键词 FROST METRE sound device
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Self-contained in situ sediment acoustic measurement system based on hydraulic driving penetration 被引量:9
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作者 Kan Guangming Liu Baohua +2 位作者 Zhao Yuexia Li Guanbao Pei Yanliang 《High Technology Letters》 EI CAS 2011年第3期311-316,共6页
A novel self-contained in situ sediment acoustic measurement system based on hydraulic driving penetration is proposed to solve the problem of large disturbances to sediments of the in situ equipments already in exist... A novel self-contained in situ sediment acoustic measurement system based on hydraulic driving penetration is proposed to solve the problem of large disturbances to sediments of the in situ equipments already in existence. By using a hydraulic driving device, the system drives four acoustic probes into sediments at an even speed, and this decreases disturbances to sediments introduced by the penetration of acoustic probes. By means of the special design of the central control unit, the system can work full-automatically and the data are stored self-containedly, and this avoids the requirement of real-time remote controlling from the ship. Its operating water depth, measuring depth and measuring frequency is 500m, 1.0m and 30kHz respectively. A set of in situ sound speeds and attenuation coefficients of sediments are obtained at 40 stations using the system. The results confirm that the data obtained by the in situ sediment acoustic system are accurate and credible. 展开更多
关键词 acoustic properties sound speed sound attenuation in situ measurement system
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Ray Theory Application in Long Baseline System 被引量:4
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作者 冀大雄 刘健 《China Ocean Engineering》 SCIE EI 2010年第1期199-206,共8页
The long baseline (LBL) system is widely used to locate and track autonomous underwater vehicles (AUV) through acoustic communication. Three important issues are presented here in LBL system application with AUV. ... The long baseline (LBL) system is widely used to locate and track autonomous underwater vehicles (AUV) through acoustic communication. Three important issues are presented here in LBL system application with AUV. Those issues which regard the normal acoustic communication between LBL system and AUV are the depth of towed army, the length of beacon cable, and the effective area of the AUV. The first issue is the key of the LBL system, which ensures the normal communication between towed array and beacons. The second issue which impacts the normal communication from the AUV to beacons in available range should be considered after the first one has been settled. Then the last issue determines the safe work area of the AUV. The ordinary differential equations (ODE) algorithm of ray is deduced from Snell's law. The ODE algorithm is applied to obtain sound rays from sound source to receiver. These problems are solved by the judgment that whether rays pinging from a sound source arrives at a receiver. The sea trial shows that these methods have much validity and practicality. 展开更多
关键词 effective area long basdine beacon cable sound track AUV
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Deep seismic sounding investigation into the deep structure of the magma system in Changbaishan-Tianchi volcanic region 被引量:6
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作者 张先康 张成科 +7 位作者 赵金仁 杨卓欣 李松林 张建狮 刘宝峰 成双喜 孙国伟 潘素珍 《Acta Seismologica Sinica(English Edition)》 CSCD 2002年第2期143-151,共9页
The magma system of Changbaishan-Tianchi Volcanic region is studied with three-dimensional deep seismic sounding (DSS) technique. The results show that the magma system of Changbaishan-Tianchi volcanic region, mainly ... The magma system of Changbaishan-Tianchi Volcanic region is studied with three-dimensional deep seismic sounding (DSS) technique. The results show that the magma system of Changbaishan-Tianchi volcanic region, mainly characterized by low velocity of P wave, can be divided into three parts in terms of depth. At the depth range of 9-15 km, the distribution of the magma system is characterized by extensiveness, large scale and near-SN orientation. This layer is the major place for magma storage. From the depth of 15 km down to the lower crust, it is characterized by small lateral scale, which indicates the 'trace' of magma intrusion from the upper mantle into the crust and also implies that the magma system most probably extends to the upper mantle, or even deeper.(less than 8-9 km deep), the range of magma distribution is even smaller, centering on an SN-oriented area just north of the Tianchi crater. If low velocity of P wave is related to the magma system, it then reflects that the magma here is still in a state of relatively high temperature. In this sense, the magma system of Changbaishan-Tianchi volcanic region is at least not 'remains', in other words, it is in an 'active' state. 展开更多
关键词 Changbaishan-Tianchi volcanic region 3-D deep seismic sounding magma system
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Ultrastructure of stridulating organ of Xylotrechus rusticus L. (Coleoptera, Cerambycidae) and behavioral responses to alarm sounds 被引量:4
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作者 LI Ling SUN Fan +2 位作者 HU Ji-hua YIN Yanbao CHI De-fu 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第3期547-552,共6页
We used scanning electron microscope (SEM) to observe the ultrastructure of stridulating organs in Xylotrechus rusticus L. We com- pared the morphological structure and size of stridulating organs, the numbers of a ... We used scanning electron microscope (SEM) to observe the ultrastructure of stridulating organs in Xylotrechus rusticus L. We com- pared the morphological structure and size of stridulating organs, the numbers of a tooth-like part used in stridulation and its presence in fe- males and males of this beetle. The alarm sound of X.. rusticus was re- corded first when it was stimulated, then we tested behavioral responses to this alarm sound. The alarm sound ofX. rusticus has a warning effect on conspecifics. 展开更多
关键词 Xylotrechus rusticus L. stridulating organ behavioral re-sponse to sound
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Spectral analysis of bowel sounds in intestinal obstruction using an electronic stethoscope 被引量:14
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作者 Siok Siong Ching Yih Kai Tan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第33期4585-4592,共8页
AIM: To determine the value of bowel sounds analysis using an electronic stethoscope to support a clinical diagnosis of intestinal obstruction. METHODS: Subjects were patients who presented with a diagnosis of possibl... AIM: To determine the value of bowel sounds analysis using an electronic stethoscope to support a clinical diagnosis of intestinal obstruction. METHODS: Subjects were patients who presented with a diagnosis of possible intestinal obstruction based on symptoms, signs, and radiological findings. A 3MTH Littmann Model 4100 electronic stethoscope was used in this study. With the patients lying supine, six 8-second recordings of bowel sounds were taken from each patient from the lower abdomen. The recordings were analysed for sound duration, soundto-sound interval, dominant frequency, and peak frequency. Clinical and radiological data were reviewed and the patients were classified as having either acute, subacute, or no bowel obstruction. Comparison of bowel sound characteristics was made between these subgroups of patients. In the presence of an obstruction, the site of obstruction was identified and bowel calibre was also measured to correlate with bowel sounds. RESULTS: A total of 71 patients were studied during the period July 2009 to January 2011. Forty patientshad acute bowel obstruction (27 small bowel obstruction and 13 large bowel obstruction), 11 had subacute bowel obstruction (eight in the small bowel and three in large bowel) and 20 had no bowel obstruction (diagnoses of other conditions were made). Twenty-five patients received surgical intervention (35.2%) during the same admission for acute abdominal conditions. A total of 426 recordings were made and 420 recordings were used for analysis. There was no significant difference in sound-to-sound interval, dominant frequency, and peak frequency among patients with acute bowel obstruction, subacute bowel obstruction, and no bowel obstruction. In acute large bowel obstruction, the sound duration was significantly longer (median 0.81 s vs 0.55 s, P = 0.021) and the dominant frequency was significantly higher (median 440 Hz vs 288 Hz, P = 0.003) when compared to acute small bowel obstruction. No significant difference was seen between acute large bowel obstruction and large bowel pseudoobstruction. For patients with small bowel obstruction, the sound-to-sound interval was significantly longer in those who subsequently underwent surgery compared with those treated non-operatively (median 1.29 s vs 0.63 s, P < 0.001). There was no correlation between bowel calibre and bowel sound characteristics in both acute small bowel obstruction and acute large bowel obstruction. CONCLUSION: Auscultation of bowel sounds is nonspecific for diagnosing bowel obstruction. Differences in sound characteristics between large bowel and small bowel obstruction may help determine the likely site of obstruction. 展开更多
关键词 Bowel sounds Intestinal obstruction Spectral analysis Electronic stethoscope
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Technological system for sustainable development of Chinese agriculture 被引量:2
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作者 Zhang Renwu Ji Wenying Zhang Tong (Agro-Environmental Protection Institute , Tianjin 300191, China) Sun Hongliang (Institute of Crop Breeding and Cultivation, Chinese Academy of Agricultural Sciences, Beijing 100081, China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1994年第4期471-477,共7页
Along with the rapid development of economy, Chinese agriculture with a long history is facingthe challenge from environment. So, the technological system for sustainable development of agriculturewith Chinese charact... Along with the rapid development of economy, Chinese agriculture with a long history is facingthe challenge from environment. So, the technological system for sustainable development of agriculturewith Chinese characteristics, which are based on the eco-economic principle, should be establisbed throughusing the approach of system engineering, carrying on the cream of Chinese traditional agricultural tech-niques and adopting modern agricultural techniques. The sustainable development should be realized on thebasis of sound cycles of economy and ecology and coordinated development between environmental protectionand economic growth or exploitation and regeneration of natural resources. 展开更多
关键词 sustainable development technological system ecoeconomy sound circulation.
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Sounds Synthesis with Slime Mould of Physarum Polycephalum 被引量:2
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作者 Eduardo R. Miranda Andrew Adamatzky Jeff Jones 《Journal of Bionic Engineering》 SCIE EI CSCD 2011年第2期107-113,共7页
This paper introduces a novel application of bionic engineering: a bionic musical instrument using Physarum polycephalum. Physarum polycephalum is a huge single cell with thousands of nuclei, which behaves like a gia... This paper introduces a novel application of bionic engineering: a bionic musical instrument using Physarum polycephalum. Physarum polycephalum is a huge single cell with thousands of nuclei, which behaves like a giant amoeba. During its foraging behavior this plasmodium produces electrical activity corresponding to different physiological states. We developed a method to render sounds from such electrical activity and thus represent spatio-temporal behavior of slime mould in a form apprehended auditorily. The electrical activity is captured by various electrodes placed on a Petri dish containing the cultured slime mold. Sounds are synthesized by a bank of parallel sinusoidal oscillators connected to the electrodes. Each electrode is responsible for one partial of the spectrum of the resulting sound. The behavior of the slime mould can be controlled to produce different timbres. 展开更多
关键词 Physarum polycephalum bionic musical instrument unconventional computing sound synthesis SONIFICATION
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TOA positioning algorithm of LBL system for underwater target based on PSO 被引量:2
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作者 XING Yao WANG Jiongqi +3 位作者 HE Zhangming ZHOU Xuanying CHEN Yuyun PAN Xiaogang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2023年第5期1319-1332,共14页
For the underwater long baseline(LBL)positioning systems,the traditional distance intersection algorithm simplifies the sound speed to a constant,and calculates the underwa-ter target position parameters with a nonlin... For the underwater long baseline(LBL)positioning systems,the traditional distance intersection algorithm simplifies the sound speed to a constant,and calculates the underwa-ter target position parameters with a nonlinear iteration.However,due to the complex underwater environment,the sound speed changes with time and space,and then the acoustic propagation path is actually a curve,which inevitably causes some errors to the traditional distance intersection positioning algorithm.To reduce the position error caused by the uncertain underwater sound speed,a new time of arrival(TOA)intersection underwater positioning algorithm of LBL system is proposed.Firstly,combined with the vertical layered model of the underwater sound speed,an implicit positioning model of TOA intersection is constructed through the constant gradient acoustic ray tracing.And then an optimization function based on the overall TOA residual square sum is advanced to solve the position parameters for the underwater target.Moreover,the particle swarm optimization(PSO)algorithm is replaced with the tra-ditional nonlinear least square method to optimize the implicit positioning model of TOA intersection.Compared with the traditional distance intersection positioning model,the TOA intersec-tion positioning model is more suitable for the engineering practice and the optimization algorithm is more effective.Simulation results show that the proposed methods in this paper can effectively improve the positioning accuracy for the underwater target. 展开更多
关键词 long baseline(LBL)positioning system sound speed profile constant gradient acoustic ray tracing time of arrival(TOA)intersection model particle swarm optimization(PSO)
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Tests of new in-situ seabed acoustic measurement system in Qingdao 被引量:1
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作者 侯正瑜 郭常升 +2 位作者 王景强 李会银 李铁刚 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第5期1172-1178,共7页
A new in-situ seabed acoustic measurement system is developed for direct in-situ measurement of sediment geoacoustic properties (compressional wave velocity and attenuation). The new in-situ system consists of two p... A new in-situ seabed acoustic measurement system is developed for direct in-situ measurement of sediment geoacoustic properties (compressional wave velocity and attenuation). The new in-situ system consists of two parts: the deck control unit and the underwater measurement unit. The underwater measurement unit emits sonic waves that propagate through the seafloor sediment, receives the returning signals, and transmits them to the deck control unit for waveform display and analysis. The entire operation is controlled and monitored in real time by the deck control unit on the research vessel and can provide recording of full waveforms to determine the sound velocity and attenuation. This paper outlines the design of the system, the measurement process, and demonstrates its application in tests carded out on seabed sediment off the Qingdao coast, China. The test results show that the system performed well and rapidly provided accurate in-situ acoustic velocity and attenuation estimates of the seafloor sediment. 展开更多
关键词 seafloor sediment in-situ measurement sound velocity and attenuation.
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A Miniature Robotic Plane Meteorological Sounding System 被引量:1
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作者 马舒庆 陈洪滨 +2 位作者 汪改 潘毅 李强 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第6期890-896,共7页
This article presents a miniature robotic plane meteorological sounding system (RPMSS), which consists of three major subsystems: a miniature robotic plane, an air-borne meteorological sounding and ?ight control sys... This article presents a miniature robotic plane meteorological sounding system (RPMSS), which consists of three major subsystems: a miniature robotic plane, an air-borne meteorological sounding and ?ight control system, and a ground-based system. Take-o? and landing of the miniature aircraft are guided by radio control, and the ?ight of the robotic plane along a pre-designed trajectory is automatically piloted by an onboard navigation system. The observed meteorological data as well as all ?ight information are sent back in real time to the ground, then displayed and recorded by the ground-based computer. The ground-based subsystem can also transmit instructions to the air-borne control subsystem. Good system performance has been demonstrated by more than 300 hours of ?ight for atmospheric sounding. 展开更多
关键词 miniature Unmanned Aerial Vehicle atmospheric sounding Flight test
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Experimental research of traction motor system for electric vehicle base on sound tensity 被引量:1
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作者 张春香 Wang Zaizhou +1 位作者 Song Qiang Zhang Chengning 《High Technology Letters》 EI CAS 2010年第1期67-69,共3页
The traction motor of electric vehicle is differing from the general industry traction motor completely. Not only frequently start, parking, accelerate, decelerate and low speed, but also high torque in climbing slope... The traction motor of electric vehicle is differing from the general industry traction motor completely. Not only frequently start, parking, accelerate, decelerate and low speed, but also high torque in climbing slope, low torque in high speed and wide range speed are requested. Base on the theory of sound intensi- ty, the experiment of noise are study through the measurement at discrete points. The sizing grid is 10mm × 10mm, The sound intensity map of traction motor are protracted at 1000r/min and the result show that the main noise sources are fan, gear-box and the traction motor in turn. 展开更多
关键词 electric vehicle traction motor noise sound intensity EXPERIMENT
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Adaptive Method for State Estimation of Sound Environment System with Uncertainty and its Application to Psychological Evaluation 被引量:1
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作者 Hisako Orimoto Akira Ikuta 《Intelligent Information Management》 2010年第3期212-219,共8页
The actual sound environment system exhibits various types of linear and non-linear characteristics, and it often contains uncertainty. Furthermore, the observations in the sound environment are often in the level-qua... The actual sound environment system exhibits various types of linear and non-linear characteristics, and it often contains uncertainty. Furthermore, the observations in the sound environment are often in the level-quantized form. In this paper, two types of methods for estimating the specific signal for sound envi-ronment systems with uncertainty and the quantized observation are proposed by introducing newly a system model of the conditional probability type and moment statistics of fuzzy events. The effectiveness of the proposed theoretical methods is confirmed by applying them to the actual problem of psychological evalua-tion for the sound environment. 展开更多
关键词 Adaptive ESTIMATION SOUND ENVIRONMENT system UNCERTAINTY PSYCHOLOGICAL Evaluation
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State Estimation for Sound Environment System with Nonlinear Observation Characteristics by Introducing Wide-Sense Particle Filter 被引量:1
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作者 Hisako Orimoto Akira Ikuta Kouji Hasegawa 《Intelligent Information Management》 2019年第6期87-101,共15页
In this study, a modified particle filter considering non-Gaussian properties of noises is proposed in a form applicable to real situation in sound environment system where the observation data are contaminated by the... In this study, a modified particle filter considering non-Gaussian properties of noises is proposed in a form applicable to real situation in sound environment system where the observation data are contaminated by the external noise (i.e., background noise) of arbitrary probability distribution and measured in decibel scale. More specifically, a nonlinear observation model in decibel scale with a quantized level is first paid considered by introducing the additive property of energy variables (i.e., sound intensity) in sound environment system. Next, a wide-sense particle filter of an expansion expression type is derived in a form suitable for the nonlinear observation characteristics and the signal processing considering higher-order correlation information between the specific signal and observation. Furthermore, the effectiveness of the proposed theory is confirmed by applying it to the observed data measured in real sound environment. 展开更多
关键词 Sound Environment NONLINEAR OBSERVATION NON-GAUSSIAN Distribution Particle Filter
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