bluuebunny/crossref_metadata_2025_split huggingface dataset:
Simulation of horizontal refraction of continental slope in the southern continental slope of the South China Sea
Authors: Liu Jin , Hu Chenghao , Wang Kai , Gao Fei , Wei Jiali 
Published: October 2024

Abstract
Sound waves are significantly influenced by boundaries during their propagation in certain environmental conditions. The extent of this impact is related to the complexity of the boundary, such as in the case of slopes and seamounts. In these areas, sound waves may deviate from their original paths, resulting in three-dimensional effects. Recent experiments and simulations have demonstrated that three-dimensional effects occur when sound waves propagate over seamounts in the South China Sea, leading to larger acoustic shadow regions. However, there are limited studies on 3D acoustic propagation based on measured slope topography or database topography. In this study, the topography of the South China Sea area database is selected, and the measured sound velocity profile and seabed acoustic parameters in the South China Sea are taken into considered. The FOR3D sound field calculation model is used to calculate the N×2D and 3D results. The simulation results show that in the southern continental slope region of the South China Sea, when the sound source frequency is 50 Hz, the acoustic wave exhibits significant horizontal refraction with a refraction angle of approximately 13°.
Distributed acoustic sensing signal event recognition and localization based on improved YOLOv7
Authors: Zhang Hongyu , Wang Chang , Zhang Faxiang , Jiang Shaodong , Sun Zhihui , Wang Xiaodong , Duan Zhenhui , Gao Fengxia , Liu Zhaoying 
Published: October 2024

Abstract
The distributed acoustic sensing (DAS) system based on phase-sensitive optical time domain reflection ( Φ-OTDR) technology is widely used in pipeline safety monitoring, perimeter security, structure monitoring, etc. Accurate localization and recognition of multi-scene events over long distances has always been a challenge. This paper proposes an improved YOLOv7 algorithm for multi-event real-time detection of DAS system. The algorithm employs space-to-depth Conv(SPD-Conv) to replace the strided convolutions and pooling operations in YOLOv7, reducing fine-grained information loss and learning of inefficient feature representations. In addition, the Convolutional Block Attention Module (CBAM) is introduced in YOLOv7 to improve the model performance. We collected spatial–temporal signal data for six types of pipeline safety events, and passed them into the improved YOLOv7 algorithm in the form of data matrixes for training and evaluation. Experiments have shown that the proposed method achieves an mAP@.5 (mean Average Precision) of 99.7% for the identification of six pipeline safety event types. Positioning loss reduced to 0.2%, and detection speed can reach 70 frames per second(FPS). Our scheme achieves significant improvements in localization and classification accuracy compared to Faster R-CNN, etc. The event recognition localization method proposed in this paper has the advantage of fast speed and high accuracy.
Research on Iron Gallium Dipole Logging Transducers
Authors: Zhao Jiaheng , Dai Yuyu , Zhou Yinqiu , Zhu Chenhui 
Published: October 2024

Abstract
Orthogonal dipole acoustic logging is an indispensable means to study the mechanical properties of formation rocks, estimate formation porosity and permeability, and carry out out-of-hole remote detection, and the broadband high-power dipole acoustic logging transducer is one of its core components, which is an urgent and unsolved international problem in actual logging. Therefore, it is of great application background and important academic significance to study the new dipole acoustic logging transducer and overcome the related scientific problems. On the basis of full investigation and study of the characteristics of iron gallium materials, this project first designed the iron gallium bending beam oscillator to verify the feasibility of iron gallium bending vibration, and then designed the iron gallium dipole acoustic logging transducer, optimized the driving magnetic circuit, simulated the driving performance of the transducer, and preliminarily verified the feasibility of the design.
Testing of battery separators: transducers and methods for air-coupled ultrasonic sensing.
Authors: Salso Patricia , Genovés Vicente , Álvarez-Arenas Tomás Gómez 
Published: October 2024

Abstract
Battery separator me3mbranes are thin polymeric microporous films placed between battery electrodes. They are a key component that strongly affects both battery performance and security and controlling its main properties is critical for the industry. In particular, the manufacturing process demands tests that allow checking both the mechanical integrity (porosity, thickness, pore size, etc.) of the materials and the consistency of these properties during the construction of the batteries. The use of an air-coupled ultrasonic system is proposed in this work. It is expected that this will make possible the non-destructive and quick testing of these materials, in order to evaluate thickness, stiffness, pore distribution and pore size of the separator. By means of three pairs of transducers, the modulus and phase of the transmission coefficient was measured from 0.35 to 1.4 MHz in different materials. The measurements show a clear modification of the film response produced by the presence of porosity. This suggests that the transmission of ultrasonic waves in battery separators using air-coupled ultrasound may have two contributions: one corresponds to the propagation though the solid part, the other corresponds to propagation in the pores. The former allows to determine properties like film thickness and elastic constants, while the latter allows to determine porosity and pore size and pore tortuosity. This work set the basis for the development of a quality test for the in-line inspection of these materials during their fabrication. The observed ultrasonic response in microporous separators suggest the possibility to use low frequency air-coupled transducers with limited sensitivity, where the use of MEM transducers at industrial scale can be advantageous.
High frequency venting of MEMS ultrasonic transducers and sensors: materials solutions.
Authors: Álvarez-Arenas T.E.G. , Salso P. , Genovés V. 
Published: October 2024

Abstract
This paper introduces the concept of ultrasonic venting. Similar to acoustic vents, ultrasonic vents refer to the aperture in air-coupled MEMS ultrasonic transducers (either PMUT or CMUT) intended to allow the equalization of internal and external pressures, the transfer of heat and the pass of ultrasonic waves, while impeding the penetration of fluids or particles that can affect the transducer membrane. To that end, vents are covered with a porous membrane whose properties are tuned to meet the afore mentioned requirements. The main difficulty in ultrasonic venting, compared with acoustic venting, is that the required “transparency” to ultrasonic waves is much more difficult to achieve. This involves two main problems as both transmission loss and frequency distortion are much larger at ultrasonic frequencies than in the audio range. The objectives of this paper are: to measure the response of acoustic venting materials in the ultrasonic frequency range, to determine the usability of these materials in ultrasonic vents, and to extract useful information for the design of efficient ultrasonic venting materials. Transmission coefficient spectra of different acoustic venting materials is measured in the frequency range 0.2 –2.7 MHz. The origin of the ultrasonic losses and frequency distortion are analysed as well as the role of mode conversion, internal interferences, modes interference, etc. Results reveal that none of the acoustic venting materials analysed can be used in ultrasonic venting applications, but the obtained knowledge about the response of these materials in the ultrasonic frequency range permit to advance in the selection of successful candidate materials for this application.
A numerical study on the relationship between local defect resonance and sub-harmonic resonance for closed cracks
Authors: Maruyama Taizo , Tanihira Tomoki , Nakahata Kazuyuki 
Published: October 2024

Abstract
The sub-harmonic resonance in closed cracks is caused by resonant properties of the system and the contact of crack surfaces. Local defect resonance is considered a potential resonant phenomenon near cracks. This study compares local resonance and sub-harmonic resonance in a surface-breaking crack using numerical simulations. The authors previously simulated nonlinear sub-harmonic resonance using the harmonic balance-boundary element method. The investigation of local defect resonance utilizes both the boundary element method and the Sakurai-Sugiura method. The numerical results indicate a strong relation between the vibration fields of sub-harmonic frequency components and local defect resonance.
Ultrasonic motion scanning method based on flexible microchannel array
Authors: Wang K. , Song Y. , Kang Y. 
Published: October 2024

Abstract
Immersion ultrasound scanning faces limitations in specific detection scenarios, such as those involving moving workpieces or highly intricate surfaces. This issue is particularly pronounced when workpieces exhibit relative motion, resulting in significant signal decay. To address this challenge, an ultrasonic motion scanning method based on a flexible microchannel array is proposed in this paper. This innovative method utilizes a flexible microchannel array as the coupling medium. Initially, the principle of water column formation within the arrays is examined. Subsequently, various shapes and sizes of arrays are meticulously analyzed. Finally, the behavior of the detection signal of the probe in motion is investigated. It is demonstrated that stable detection results can be achieved even while the ultrasound probe is in motion.
Novel Surface Acoustic Wave Strain Sensor with Enhanced High-Temperature Performance and Resistance to Aging
Authors: Zhang Jikai , Mu Danyu , Zhang Zichao , Jin Hao , Chen Jinkai , Xuan Weipeng , Dong Shurong , Luo Jikui 
Published: October 2024

Abstract
Surface acoustic wave (SAW) sensors based on Langasite (La3Ga5SiO14, LGS) have emerged as promising candidates for high-temperature strain measurement in passive wireless systems. However, limitations of strain transfer at temperatures above 800°C have hindered the repeatability of sensors due to temperature-induced effects. For instance, the aging of conventional high-temperature adhesives at elevated temperatures restricts the strain transfer between the measured object and the sensor. Moreover, materials like Inconel-600 exhibit a coefficient of thermal expansion significantly larger than the LGS, leading to thermal strains caused by thermal expansion mismatch beyond the maximum range of existing SAW strain sensors. Such factors increase the likelihood of sensor damage during a test. In this paper, we present a novel SAW sensor utilizing an ultra-thin LGS substrate encapsulated within a ceramic coating, which transfers strain by exerting pressure on both sides of the sensor. The strain sensor is mounted on an equal-strain beam inside a high-temperature furnace. The ceramic coating is not tightly bonded to the sensor, thereby mitigating the thermal expansion mismatch between the sensor and the beam at high temperatures. Furthermore, the ceramic coating can withstand large strain caused by thermal expansion while maintaining pressure on the sensor. This innovative SAW sensor enables repeat strain tests up to 800°C, including both calibration and formal tests. The measured strain exhibits an error of less than 5% compared to a standard strain gauge, demonstrating the sensor’s enhanced performance and reliability.
A distributed parameter model of the cavity-loaded piston transducer
Authors: Liu Wenzhao , Mo Xiping , Chai Yong , Zhang Xiuzhen , Pan Rui 
Published: October 2024

Abstract
Adding a cylindrical liquid cavity at the radiation surface of a piston transducer can introduce the liquid cavity resonance into the vibration system, thereby extending the operating bandwidth of the transducer. However, recent studies have shown that effective coupling of the liquid cavity resonance with the self-resonance of the piston transducer presents difficulties, resulting in significant fluctuations in the transmitting voltage response (TVR) within the operating frequency band. The physical mechanism behind this phenomenon remains unclear to date. In this paper, a distributed parameter model (DPM) for the cavity-loaded piston transducer is proposed. The admittance, amplitude and phase of the vibration velocity and TVR of the transducer are calculated using both DPM and finite element method (FEM). The results from DPM and FEM exhibit good agreement, indicating that the DPM can accurately describe the vibration characteristics of the transducer. Finally, two physical analogies of the transducer are proposed and explanations for the large fluctuations in TVR are given. This study reveals the modal coupling mechanism of the cavity-loaded piston transducer, and provides theoretical support for the analysis and designs of such transducers.
A Miniature PMUT Array for Medical Applications
Authors: Chen Jingqi , Liu Hanzhang , Zhang Xiaoduo , Li Hui , Yin Feng 
Published: October 2024

Abstract
Wearable continuous monitoring technology and internal and cerebrovascular imaging are the frontier hot area of current scientific research, which are of great significance to improving human life and health. Ultrasonic imaging can obtain information such as deep tissue structure by transmitting ultrasonic waves into the tissue and detecting echo signals, and ultrasonic imaging technology has the advantages of high imaging depth, high resolution, high safety, fast and convenient, etc. It is one of the important technologies in the medical field such as wearable continuous monitoring technology and internal cardiovascular and cerebrovascular imaging. But miniaturization and low power consumption are necessary conditions for the success of such medical applications. Therefore, the ultrasonic imaging technology using a miniature ultrasonic probe is one of the most promising imaging technologies for this type of medical application. Aiming at the common technical problems of traditional ultrasonic transducers such as large volume, narrow bandwidth, high power consumption, difficulty in preparing two-dimensional arrays, and difficulty in integrating with ICs. In this paper, the electromechanical-acoustic multi-field coupling mechanism and array structure design technology of MEMS high-performance PMUT ultrasonic transducer elements are first studied, and a CMOS-compatible miniature PMUT high-performance array ultrasonic device suitable for this type of medical application is developed. The simulation results of the transducer are given. The measurement of various physical parameters of the transducer sample and the results of its application in the ultrasonic imaging system show that the miniature PMUT linear array ultrasonic sensor we designed is a kind of high performance ultrasonic array sensors that can be widely used in wearable continuous monitoring technology and internal cardiovascular and cerebrovascular imaging.
Design of an Anti-interference long-range acoustic Communication System Based on optimal length segment coding
Authors: Zhang Luwei , Wang Jiawei , Ke Qihui , Zhou Xuanyi , Wang Xiao , Tao Jianfeng 
Published: October 2024

Abstract
With the increased demand for unmanned vehicles in marine development, the development of underwater acoustic communication technology has received much attention. One of the key technologies in the research of long-range underwater acoustic communication technology is the use of underwater acoustic channels for efficient and stable data transmission. The harsh environment of the underwater acoustic channel has a significant impact on the rate and quality of underwater acoustic communication, making it a challenging research direction to achieve high-speed and reliable telecommunication systems underwater. In this paper, a high-speed remote command-based communication system is investigated, and a long-range acoustic communication system with good adaptability to sudden and continuous interference is designed based on a remote unmanned platform. A method for encoding the communication message in segments of optimal length is proposed in this paper. This coding method can enhance the anti-sudden interference capability of the communication system which has a certain degree of communication confidentiality, and the performance of this anti-interference communication system is verified by laboratory tests and field tests. The verification results show that the proposed telecommunication system based on optimal length segment coding has better performance in anti-sudden interference and continuous interference, which can make the communication system performance more stable and increase the success rate of command-based communication significantly.
Surface acoustic waves in porous soils with two-layered infiltration
Authors: Fomenko Sergey I. , Jana Raghavendra B. 
Published: October 2024

Abstract
Two stage mathematical and computer models based on the finite element solution of Richards’ equation for water infiltration in two-layered fluid-saturated soil and modal analysis using a semi-analytical approach for vertically stratified soils are presented and briefly described. Dispersion curves of surface waves in the layered poroelastic half-space are computed and studied. The features of porous water infiltration effect on the characteristics of surface elastic waves are discussed.
Sound source localization based on microphone array mounted on unmanned aerial vehicles
Authors: Wang Hongzhao , Guo Xinhua 
Published: October 2024

Abstract
Microphone array installed on unmanned aerial vehicles (UAV) can be used for acoustic detection in scenes, such as detecting noise sources in factories or monitoring corona in power grids. However, using acoustic sensors on UAV has great challenges. The motor rotation of UAV and the non-stationary noise generated by propeller make it difficult for microphone array to obtain useful information for sound source localization. In order to reduce self-noise, an improved least mean square (LMS) adaptive filtering algorithm is proposed. Combining filtering algorithm and multiple signal classification (MUSIC) algorithm to locate the sound source, the noise spectrum characteristics of UAV in outdoor free flight mode are analyzed. The microphone array is used to collect data and realize sound source localization in low Signal-to-Noise Ratio (SNR) environment. The simulation and experimental results show that the algorithm improves the robustness of the sound source localization algorithm in low SNR environment, and realizes the real-time localization of the target sound source during the flight of UAV with microphone array.
Research on ultrasonic phased array total focusing multi-mode fusion method
Authors: Bu Yangguang , Cheng Jingwei , Chen Wei , Li Rui , Wang Zhe , Wang Haibin , Yan Chang , Ji Tian , Li Kang , Chen Zhe 
Published: October 2024

Abstract
Welded seams are one of the important structural forms in the construction of industrial equipment. But during use, hazardous defects may occur within the weld. Ultrasonic phased-array total focusing method (TFM) is a relatively new post-processing imaging method that can locate defects. In this study, a multi-mode ultrasonic phased-array total focusing fusion method was explored for weld defects to achieve effective quantification and localization of different types of defects. This study explores the application of different fusion methods such as maximum fusion, average fusion and effective region fusion in multi-mode phased array total focusing method. The experimental results show that the fusion methods can improve the accuracy of defect detection compared to single imaging methods, but the effective area fusion method has the best results in detecting weld defects. Taken together, the effective region fusion method can effectively improve the resolution and signal-to-noise ratio of multi-mode imaging methods.
Effects of interlayer SiO2 or Au on the performances of LNOS-SAW
Authors: Lin Binghui , Gao Chao , Wang Yaxin , Zou Yang , Liu Yan , Liu Wenjuan , Cai Yao , Sun Chengliang 
Published: October 2024

Abstract
Surface acoustic wave (SAW) resonators and filters based on lithium niobate (LN) or lithium tantalate crystals have been widely used in modern wireless communication systems. However, acoustic energy in these kinds of devices is lost in the substrate due to longitudinal attenuation. The enhancements of quality factor and coupling coefficient are still in demand for further applications. This work proposes a SAW based on LN thin film on a sapphire substrate (LNOS). Besides, we explored the effects of using different bonding materials on the LNOS-SAW performances. The presence of the interlayer not only plays a role in bonding but also has an impact on the performance of the resonator. Considering the compatibility of the process in this method, 2 μm-thick silicon dioxide (SiO2) or 1 μm-thick gold (Au) is designed as the interlayer. As the displacement diagrams show, the acoustic energy of the SAW with interlayer is reflected at the interface, and the energy leakage is suppressed. The simulation results show that the presence of SiO2 or Au causes a decrease in resonant frequencies of the resonators, and the effect is more pronounced with Au. Significantly, the presence of SiO2 enhances the coupling efficiency of the resonator while the Au interlayer brings a more obvious improvement in the quality factor.
High-resolution assessment of wind energy potential in the Hami region of Northwestern China
Authors: Xu Jiayu , Tao Yiheng , Yang Shuai , Zou Junyu , Duan Weili , Chen Yuntian , Ye Fan , Ning Jiangmin , Zeng Zhenzhong 
Published: October 2024

Abstract
Wind energy plays a pivotal role in the global effort to mitigate climate change, with China emerging as a leader in renewable energy adoption. The Hami region in northwestern China stands out as a crucial area for wind power development, given its substantial wind resources and strategic importance in China’s energy landscape. However, existing studies on wind energy potential vary widely and involve large uncertainties due to sparse measurements and coarse resolution, highlighting the need for more precise assessments to guide policy decisions and optimize energy utilization. This study leverages high-resolution ERA5 reanalysis data and advanced wind turbine technology to assess wind energy potential in the Hami region, taking into account factors including wind speed patterns, turbine heights, and geographical constraints. The comparison with in-situ data demonstrated that high-resolution ERA5 reanalyzed wind speeds enable to capture multi-year wind speed variations in this region. We find substantial potential for wind energy in Hami, with energy densities exceeding 200 W m−2 in the high-potential wind zones. Importantly, this study identifies a new high-potential area in eastern Hami, termed the East Wind Zone. Our high-resolution assessment of wind energy potential at different heights over the past two decades reveals long-term trends and seasonal variations. Increasing the hub height from 95 m to 140 m raises the average wind power generation potential across Hami by 31.3 GWh yr−1. Our findings highlight the importance of strategic wind farm placement to maximize renewable energy output and provide insights for policy and industry, supporting China’s renewable energy goals.