Results 21 to 30 of about 476 (147)

Experimental verification of the potential of superhydrophobic surfaces in reducing audible noise on HVAC overhead line conductors

High Voltage, 2022
Overhead line conductors can generate audible noise across a wide frequency spectrum as a result of elevated electric fields at the conductor surface. Such fields are enhanced by the presence of surface defects, insects, water drops and pollution. Within
Xu Zhang, Ian Cotton, Qi Li, Simon M. Rowland, Christopher Emersic, Chengxing Lian, Wenyuan Li   +6 more
doaj   +1 more source

A novel semi-analytical methodology for predicting sound absorption of anechoic coatings with arbitrary rotary cavities dependent on temperature and frequency

Results in Physics, 2021
In response to the shortcomings of existing studies on the sound-absorbing characteristics of an anechoic coating, which most ignore the frequency factor and are expensive for temperature-tunable hydroacoustic experiments, a novel semi-analytical ...
Zhifu Zhang, Jiaxuan Wang, Qibai Huang
doaj   +1 more source

A hybrid acoustic structure for low-frequency and broadband underwater sound absorption

Journal of Low Frequency Noise, Vibration and Active Control, 2022
The underwater anechoic coating with local resonant units is an effective method to achieve low-frequency sound absorption. However, the structure obtained in this way is not satisfactory in the sound absorption effect of mid-high frequency bands ...
Xinyu Jia, Guoyong Jin, Kangkang Shi, Chunyang Bu, Tiangui Ye   +4 more
doaj   +1 more source

Acoustic behavior of composites with gradient impedance

Materials & Design, 2020
Conventional acoustic materials with uniform media which are of fixed impedance and density are unable to satisfy the requirements of the development of modern acoustic technology in volume, weight, pressure resistance and stealth performance.
Yiwen Feng, Jing Qiao, Longqiu Li
doaj   +1 more source

Numerical simulation of a viscoelastic sound absorbent coating with a doubly periodic array of cavities

Cogent Engineering, 2018
Nowadays, research on underwater sound absorbing coatings is important on marine combats. Due to high cost of acoustic experimental tests, determination of an accurate simulation method for assessment of the coating characteristics is an important goal ...
Sayed Hamid Sohrabi, Mohammad Javad Ketabdari   +1 more
doaj   +1 more source

Analysis of the anechoic properties of viscoelastic coatings with periodically distributed cavities

Acta Physica Sinica, 2007
Using an exact Mie scattering solution, the scattering and vibration mode of a single air sphere in unbounded rubber are analyzed with reference to the elements of the scattering matrix. Then, using the multiple_scattering method, the anechoic properties of the viscoelastic rubber coating (with a thickness of 8mm) containing a plane of periodically ...
null Zhao Hong-Gang, null Liu Yao-Zong, null Wen Ji-Hong, null Yu Dian-Long, null Wen Xi-Sen   +4 more
openaire   +1 more source

Modeling and Output Optimization of Triboelectric Microphone for Acoustic Energy Harvesting

ENERGY &ENVIRONMENTAL MATERIALS, EarlyView.
This work elucidates the fundamental multiphysics coupling mechanisms governing acoustic T‐phone, providing a critical theoretical foundation and a predictive design paradigm for the future engineering and deployment of next‐generation, self‐powered acoustic sensors.
Dan Liu, Jie Zhu, Shilong Wang, Chaobin Jia, Tao Jiang, Guofei Zhou, Jiajia Shao   +6 more
wiley   +1 more source

An ultra-thin quad-band metamaterial inspired absorber using symmetric bent-arrow shaped resonator for sensing and imaging in defense applications

Materials Research Express, 2020
In this paper, a novel compact quad-band polarization insensitive metamaterial absorber has been proposed to be employable in the microwave frequency regime.
Raghvenda Kumar Singh, Ashish Gupta, Anand Sharma, Utkarsh Tyagi, Nishchay Gupta, Akash Yadav   +5 more
doaj   +1 more source

Conformal and Multi‐Domain Radio Frequency Energy Harvesting System Based on Graphene for Internet of Things Applications

Interdisciplinary Materials, EarlyView.
This study details a multi‐domain graphene assembled film (GAF) based radio frequency (RF) energy harvesting system (GEHS) for Internet of Things (IoT) applications. The GEHS integrates a flexible dual‐band, dual‐polarization, dual‐beam antenna array based on GAF materials with a high‐efficiency rectifier.
Yitong Xin, Rongguo Song, Haoran Zu, Wei Qian, Bo Liu, Wenjun Wang, Yunfa Si, Zhe Wang, Ruixue Zhang, Jiannan Guo, Jingwei Zhang, Boyang Mao, Daping He   +12 more
wiley   +1 more source

Analysis of High‐Risk Factors for Failure of Bleeding Control in Enhanced Myometrial Vascularity Treated With Uterine Artery Embolization

Journal of Clinical Ultrasound, EarlyView.
Enhanced Myometrial Vascularity (EMV) is a serious gynecological condition that often leads to abnormal uterine bleeding. Malformation size and involvement of the uterine fundus are significant risk factors. If EMV diameter > 3.85 cm, the bleeding of the patient is more likely to result in failure in UAE treatment.
Linhua Zhu, Yongfang Yue, Lili Cao
wiley   +1 more source