资源类型

期刊论文 60

年份

2024 1

2023 4

2022 2

2021 6

2020 6

2019 2

2018 6

2017 4

2016 4

2015 2

2013 1

2012 2

2011 1

2009 3

2008 6

2006 1

2005 3

2003 2

2002 1

2001 3

展开 ︾

关键词

噪声 2

湍流边界层 2

直接数值模拟 2

相干结构 2

CFD 1

CMOS；跨导提升技术；低噪声放大器；变压器；共栅级 1

FGR预测 1

SARS 1

主动噪声控制（ANC）；过滤扩展最小均方（FXLMS）；模拟计算；遗传算法；内点法 1

事件定位 1

二次防御 1

人工噪声；多天线系统；保密中断概率；无线携能 1

伪码 1

保持边缘的自适应滤波器 1

信号叠加 1

信号增强 1

信号消噪；深度自适应阈值学习网络；多尺度特征融合；调制识别 1

信噪比 1

信干比增益 1

展开 ︾

检索范围：

排序： 展示方式：

A hybrid deep learning model for robust prediction of the dimensional accuracy in precision milling of thin-walled structural components

《机械工程前沿（英文）》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0688-0

摘要： The use of artificial intelligence to process sensor data and predict the dimensional accuracy of machined parts is of great interest to the manufacturing community and can facilitate the intelligent production of many key engineering components. In this study, we develop a predictive model of the dimensional accuracy for precision milling of thin-walled structural components. The aim is to classify three typical features of a structural component—squares, slots, and holes—into various categories based on their dimensional errors (i.e., “high precision,” “pass,” and “unqualified”). Two different types of classification schemes have been considered in this study: those that perform feature extraction by using the convolutional neural networks and those based on an explicit feature extraction procedure. The classification accuracy of the popular machine learning methods has been evaluated in comparison with the proposed deep learning model. Based on the experimental data collected during the milling experiments, the proposed model proved to be capable of predicting dimensional accuracy using cutting parameters (i.e., “static features”) and cutting-force data (i.e., “dynamic features”). The average classification accuracy obtained using the proposed deep learning model was 9.55% higher than the best machine learning algorithm considered in this paper. Moreover, the robustness of the hybrid model has been studied by considering the white Gaussian and coherent noises. Hence, the proposed hybrid model provides an efficient way of fusing different sources of process data and can be adopted for prediction of the machining quality in noisy environments.

关键词： precision milling     dimensional accuracy     cutting force     convolutional neural networks     coherent noise    

HTML PDF 收藏

Moving target detection in the cepstrum domain for passive coherent location (PCL) radar

Ji-chuan LI,Xiao-de LU,Hui ZHANG,Peng-cheng YANG,Yu LIU,Mao-sheng XIANG

《信息与电子工程前沿（英文）》 2015年 第16卷 第9期   页码 785-795 doi: 10.1631/FITEE.1500036

摘要： A cepstrum moving target detection (CEPMTD) algorithm based on cepstrum techniques is proposed for passive coherent location (PCL) radar systems. The primary cepstrum techniques are of great success in recognizing the arrival times of static target echoes. To estimate the Doppler frequencies of moving targets, we divide the radar data into a large number of segments, and reformat these segments into a detection matrix. Applying the cepstrum and the Fourier transform to the fast and slow time dimensions respectively, we can obtain the range information and Doppler information of the moving targets. Based on the CEPMTD outlined above, an improved CEPMTD algorithm is proposed to improve the detection performance. Theoretical analyses show that only the target’s peak can be coherently added. The performance of the improved CEPMTD is initially validated by simulations, and then by experiments. The simulation results show that the detection performance of the improved CEPMTD algorithm is 13.3 dB better than that of the CEPMTD algorithm and 6.4 dB better than that of the classical detection algorithm based on the radar cross ambiguity function (CAF). The experiment results show that the detection performance of the improved CEPMTD algorithm is 1.63 dB better than that of the radar CAF.

关键词： Moving target detection     Cepstrum techniques     Cross ambiguity function (CAF)     Passive coherent location (PCL) radar    

HTML PDF 收藏

压力梯度作用下相干结构的演化

陆利蓬,李兆瑞

《中国工程科学》 2002年 第4卷 第11期   页码 50-56

摘要：

采用共振三波的一个周期作为湍流边界层近壁区相干结构的初值，用直接数值模拟方法对有压力梯度，包括定常压力梯度和变压力梯度作用下相干结构的演化进行了研究，得出其各种特性的变化与实验观测到的结果一致。压力梯度对相干结构初始扰动波的选择以及演化过程都起作用，相比之下对前者的作用更大。条纹结构和流向涡之间有某种内在的紧密的联系，可能是产生流向涡的起因。

关键词： 相干结构     湍流边界层     压力梯度     直接数值模拟    

HTML PDF 收藏

Design of noise-reduction seats for high-speed trains

Xiaojun DENG, Yanju ZHAO, Haijin ZHANG, Renzhong SHUAI, Leiwei ZHU

《机械工程前沿（英文）》 2018年 第13卷 第3期   页码 385-389 doi: 10.1007/s11465-017-0438-x

摘要：

Noise-reduction seats have been successfully used in concert halls, theaters, and other places that reduce noise. In this study, a new noise-reduction seat design was proposed for high-speed trains, which have unique interior noise spectral characteristics. First, before the noise-reduction seat models were fabricated, the parameters of high-performance sound-absorbing materials and perforated plates were selected by conducting a standing-wave tube test. The sound-absorption effects of the noise-reduction seats and normal seats were investigated and compared in a reverberation chamber. Test results showed that, compared with normal seats, the noise-reduction seats obtained a significantly improved sound-absorption coefficient in the entire frequency band. Furthermore, the test results were used to establish a simulation model for calculation, and the simulation results proved that the noise-reduction seats substantially reduced the noise in an entire train car. Finally, the noise-reduction seats were fabricated and installed in a full train car of an actual high-speed train. The test results showed that, compared with the normal seats, the noise-reduction seats decreased the noise level at a standard point in the passenger car by 1.5 dB. Therefore, the noise-reduction seats are effective in noise reduction.

关键词： high-speed train     sound-absorbing materials     perforated board     noise-reduction seats    

HTML PDF 收藏

Anovel approach of noise statistics estimate using H∞ filter in target tracking

Xie WANG,Mei-qin LIU,Zhen FAN,Sen-lin ZHANG

《信息与电子工程前沿（英文）》 2016年 第17卷 第5期   页码 449-457 doi: 10.1631/FITEE.1500262

摘要： Noise statistics are essential for estimation performance. In practical situations, however, a priori information of noise statistics is often imperfect. Previous work on noise statistics identification in linear systems still requires initial prior knowledge of the noise. A novel approach is presented in this paper to solve this paradox. First, we apply the H∞ filter to obtain the system state estimates without the common assumptions about the noise in conventional adaptive filters. Then by applying state estimates obtained from the H∞ filter, better estimates of the noise mean and covariance can be achieved, which can improve the performance of estimation. The proposed approach makes the best use of the system knowledge without a priori information with modest computation cost, which makes it possible to be applied online. Finally, numerical examples are presented to show the efficiency of this approach.

关键词： Noise estimate     H∞     filter     Target tracking    

HTML PDF 收藏

珊瑚岛礁环境噪声成像 Article

夏少红, 张昌榕, 曹敬贺

《工程（英文）》 2023年 第25卷 第6期   页码 182-193 doi: 10.1016/j.eng.2021.09.022

摘要：

As valuable land in the ocean, coral islands are not only important bases for making use of marine resources and protecting marine rights and interests, but also important for breakthrough research in many fields of earth science. Hence, the economical and efficient determination of the underground structure of coral islands has become significant in coral island engineering geology, but remains challenging for traditional marine geophysical prospecting and drilling methods. While ambient noise tomography with dense arrays has been widely used in continental regions, its applicability to coral islands remains undetermined. In this study, based on the data recorded by a dense array on an isolated coral island in the South China Sea, we analyzed the ambient noise characteristics and obtained a 3D subsurface structure of the coral island using ambient noise tomography. We made the following findings: ① The ambient noise frequencies can be roughly categorized into three levels: < 1, 1–5, and > 5 Hz. The spectral characteristics of the noise below 5 Hz were consistent at different stations, but there were significant differences in the characteristics of the noise above 5 Hz. ② For ambient noise frequencies below 5 Hz, cross-correlation functions with high quality could be obtained with only 24 h of waveform data. However, it was difficult to extract meaningful cross-correlation functions for ambient noise frequencies above 5 Hz. ③ The S-wave velocity in the coral island was higher toward the sea and lower toward the lagoon, which was consistent with the high degree of cementation of the outer reef flat stratum on the seaward side. ④ There were two low-velocity horizons at 25–75 and 200–300 m, which were in good agreement with the high-porosity horizons that were revealed by drilling core samples, reflecting the weathering history of the reef. Our research demonstrates that ambient noise tomography is a potentially economical, efficient, and environmentally friendly method for the geological prospecting of coral reefs.

关键词： Coral island     Ambient noise tomography     Engineering geology     South China Sea    

HTML PDF 收藏

Investigation of flow dynamics and decrease of vortex noise inside volute of centrifugal fans

LI Chunxi, WANG Songling

《能源前沿（英文）》 2008年 第2卷 第2期   页码 235-240 doi: 10.1007/s11708-008-0040-3

摘要： The characteristics of three-dimension flow dynamics inside the volute of a G4-73No.8D centrifugal fan was simulated numerically using a computational fluid dynamics(CFD) technique. The generation, evolution, and noise of the vortex were investigated when cylinder-shaped and cone-cylinder-shaped anti-vortex rings were added separately. Numerical results showed that large-scale vortices were broken effectively and the flow fields inside the fan were more uniform with the two anti-vortex rings installed. Experimental results indicated A-sound level and spectrum noise of the refitted fan decreased and the two anti-vortex rings were effective in decreasing vortex noise. The cone-cylinder-shaped anti-vortex ring was more effective than the cylinder-shaped one in breaking large-scale vortexes and decreasing vortex noise.

关键词： cylinder-shaped     evolution     computational     effective     large-scale    

HTML PDF 收藏

Application of python-based Abaqus preprocess and postprocess technique in analysis of gearbox vibration and noise

Guilian YI, Yunkang SUI, Jiazheng DU

《机械工程前沿（英文）》 2011年 第6卷 第2期   页码 229-234 doi: 10.1007/s11465-011-0128-z

摘要：

To reduce vibration and noise, a damping layer and constraint layer are usually pasted on the inner surface of a gearbox thin shell, and their thicknesses are the main parameters in the vibration and noise reduction design. The normal acceleration of the point on the gearbox surface is the main index that can reflect the vibration and noise of that point, and the normal accelerations of different points can reflect the degree of the vibration and noise of the whole structure. The K-S function is adopted to process many points’ normal accelerations as the comprehensive index of the vibration characteristics of the whole structure, and the vibration acceleration level is adopted to measure the degree of the vibration and noise. Secondary development of the Abaqus preprocess and postprocess on the basis of the Python scripting programming automatically modifies the model parameters, submits the job, and restarts the analysis totally, which avoids the tedious work of returning to the Abaqus/CAE for modifying and resubmitting and improves the speed of the preprocess and postprocess and the computational efficiency.

关键词： Abaqus secondary development     Python language     vibration and noise reduction     K-S function     vibration acceleration level    

HTML PDF 收藏

Integrated virtual-design methods for forecasting radiated noise of single cylinder diesel block

GUO Lei, HAO Zhiyong, XU Hongmei, LIU Lianyun

《能源前沿（英文）》 2008年 第2卷 第4期   页码 416-421 doi: 10.1007/s11708-008-0097-z

摘要： The two cycle dynamical results, such as the bearing load, the piston thrust, and the load spatial distribution etc., were obtained by hybrid dynamical simulation of the flexible assembly of the block and crank-train. The finite element model of the block was validated by modal test. The frequency response of the block was calculated using the finite element method (FEM). Finally, the radiated noise such as sound power level and efficiency in the out sound field were obtained using the direct boundary element method (BEM).

关键词： bearing     dynamical     frequency response     dynamical simulation     hybrid dynamical    

HTML PDF 收藏

of structural responses using an optimal passive tuned mass damper under stationary Gaussian white noise

Min-Ho CHEY, Jae-Ung KIM

《结构与土木工程前沿（英文）》 2012年 第6卷 第3期   页码 267-280 doi: 10.1007/s11709-012-0170-x

摘要： In this study, the structural control strategy utilizing a passive tuned mass damper (TMD) system as a seismic damping device is outlined, highlighting the parametric optimization approach for displacement and acceleration control. The theory of stationary random processes and complex frequency response functions are explained and adopted. For the vibration control of an undamped structure, the optimal parameters of a TMD, such as the optimal tuning frequency and optimal damping ratio, to stationary Gaussian white noise acceleration are investigated by using a parametric optimization procedure. For damped structures, a numerical searching technique is used to obtain the optimal parameters of the TMD, and then the explicit formulae for these optimal parameters are derived through a sequence of curve-fitting schemes. Using these specified optimal parameters, several different controlled responses are examined, and then the displacement and acceleration based control effectiveness indices of the TMD are examined from the view point of RMS values. From the viewpoint of the RMS values of displacement and acceleration, the optimal TMDs adopted in this study shows clear performance improvements for the simplified model examined, and this means that the effective optimization of the TMD has a good potential as a customized target response-based structural strategy.

关键词： tuned mass damper     parametric optimization     passive control     white noise     earthquake excitation    

HTML PDF 收藏

单中继系统中基于空间信道配对和相干合并的交替迭代结构 Article

Feng SHU,Xiao-hui HUANG,Jin-song HU,Ting-ting LIU,Ri-qing CHEN,Xiao-hu YOU,Jun LI,Jin WANG

《信息与电子工程前沿（英文）》 2016年 第17卷 第9期   页码 938-945 doi: 10.1631/FITEE.1500436

摘要： 概要：在单中继系统中，对于给定空间信道配对（spatial channel pairing, SCP）方案，可以推导出最佳相干合并的闭式解；对于给定相干合并方案，也可以得到SCP的近似解析解。由此，本文设计了一种基于SCP和相干合并的交替迭代结构。仿真结果表明：相较于现有的最大比合并加匹配滤波，最大比合并加天线选择以及分布式空时码算法，本文提出的交替迭代结构能够提供更为可观的信噪比增益。

关键词： 空间信道配对；相干合并；交替迭代结构；误符号率；分布式空时码    

HTML PDF 收藏

Multi-UAV cooperative target tracking with bounded noise for connectivity preservation

Rui Zhou, Yu Feng, Bin Di, Jiang Zhao, Yan Hu,jzhao@buaa.edu.cn

《信息与电子工程前沿（英文）》 2020年 第21卷 第10期   页码 1413-1534 doi: 10.1631/FITEE.1900617

摘要： We investigate cooperative target tracking of multiple unmanned aerial vehicles (UAVs) with a limited communication range. This is an integration of UAV motion control, target state estimation, and network topology control. We first present the communication topology and basic notations for , and introduce the distributed . Then, convergence and boundedness of the estimation errors using the filter are analyzed, and potential functions are proposed for communication link maintenance and collision avoidance. By taking stable target tracking into account, a distributed potential function based UAV motion controller is discussed. Since only the estimation of the target state rather than the state itself is available for UAV motion control and UAV motion can also affect the accuracy of state estimation, it is clear that the UAV motion control and target state estimation are coupled. Finally, the stability and convergence properties of the coupled system under are analyzed in detail and demonstrated by simulations.
HTML PDF 收藏

Numerical analysis of aerodynamic noise radiated from cross flow fan

CHEN Anbang, LI Song, HUANG Dongtao

《能源前沿（英文）》 2008年 第2卷 第4期   页码 443-447 doi: 10.1007/s11708-008-0063-9

摘要： The flow field in a cross flow fan was simulated by solving the 2-D unsteady Reynolds-averaged Navier-Stokes equations. The calculated pressure fluctuations of the blades, the vortex wall, and the rear wall were then used as noise sources to calculate the sound field. The Ffowcs Williams-Hawkings (FW-H) equation was employed to predict the noise field caused by these sources. The predictions show that the rear wall and the vortex wall sources contribute significantly to the total noise and that both the predicted aerodynamic performance and noise agree well with the experimental results.

关键词： predicted aerodynamic     Williams-Hawkings     calculated pressure     aerodynamic performance     unsteady Reynolds-averaged    

HTML PDF 收藏

Air-borne noise of thermal module and system for notebook personal computers: experimental study

SHI Junye, JIANG Cailing, QIAO Junsheng, CHEN Jiangpin, LI Xiaoping, ZHANG Xiaojun

《能源前沿（英文）》 2008年 第2卷 第2期   页码 174-178 doi: 10.1007/s11708-008-0034-1

摘要： Thermal performance is the most important issue to be considered when a thermal module is designed for a notebook personal computer (PC). Because the fan causes air-borne noise and affects the user’s comfort, the acoustic characteristics of the module attract more attention. Experiments were conducted to study the noise sources, the noise characteristic and the main factors influencing the noise level. The difference between the air-borne noise of the thermal module and the whole computer system was analyzed and its propagating characteristics were derived. The influence of I/O ports on the air-borne noise was also studied experimentally.

关键词： air-borne     attention     propagating     characteristic     personal computer    

HTML PDF 收藏

基于位置旋转变换和非均匀快速傅立叶变换的机动目标高效相参检测 Research Articles

靳科1,赖涛2,齐艳丽3,黄洁1,赵拥军1

《信息与电子工程前沿（英文）》 2020年 第21卷 第8期   页码 1251-1266 doi: 10.1631/FITEE.1900272

摘要： 长时间相参积累能够显著提升雷达对机动目标的检测和运动参数估计性能。然而，相参积累期间目标的线性距离徙动、二次距离徙动和多普勒频率徙动将导致检测性能急剧下降。提出基于位置旋转变换和非均匀快速傅里叶变换的高效稳健相参积累方法。首先，利用二阶Keystone变换消除二次距离徙动。然后，利用旋转角度和多普勒频率之间的对应关系，构建相位补偿函数，从而利用位置旋转和非均匀快速傅里叶变换实现高效的参数估计。与现有代表性算法相比，所提算法能以较低运算复杂度实现近乎理想的检测性能。最后，基于雷达实测数据的实验证明所提算法有效。

关键词： 相参积累；机动目标；参数估计；位置旋转变换；非均匀快速傅立叶变换    

HTML PDF 收藏

标题 作者 时间 类型 操作

A hybrid deep learning model for robust prediction of the dimensional accuracy in precision milling of thin-walled structural components

期刊论文

Moving target detection in the cepstrum domain for passive coherent location (PCL) radar

Ji-chuan LI,Xiao-de LU,Hui ZHANG,Peng-cheng YANG,Yu LIU,Mao-sheng XIANG

期刊论文

压力梯度作用下相干结构的演化

陆利蓬,李兆瑞

期刊论文

Design of noise-reduction seats for high-speed trains

Xiaojun DENG, Yanju ZHAO, Haijin ZHANG, Renzhong SHUAI, Leiwei ZHU

期刊论文

Anovel approach of noise statistics estimate using H∞ filter in target tracking

Xie WANG,Mei-qin LIU,Zhen FAN,Sen-lin ZHANG

期刊论文

珊瑚岛礁环境噪声成像

夏少红, 张昌榕, 曹敬贺

期刊论文

Investigation of flow dynamics and decrease of vortex noise inside volute of centrifugal fans

LI Chunxi, WANG Songling

期刊论文

Application of python-based Abaqus preprocess and postprocess technique in analysis of gearbox vibration and noise

Guilian YI, Yunkang SUI, Jiazheng DU

期刊论文

Integrated virtual-design methods for forecasting radiated noise of single cylinder diesel block

GUO Lei, HAO Zhiyong, XU Hongmei, LIU Lianyun

期刊论文

of structural responses using an optimal passive tuned mass damper under stationary Gaussian white noise

Min-Ho CHEY, Jae-Ung KIM

期刊论文

单中继系统中基于空间信道配对和相干合并的交替迭代结构

Feng SHU,Xiao-hui HUANG,Jin-song HU,Ting-ting LIU,Ri-qing CHEN,Xiao-hu YOU,Jun LI,Jin WANG

期刊论文

Multi-UAV cooperative target tracking with bounded noise for connectivity preservation

Rui Zhou, Yu Feng, Bin Di, Jiang Zhao, Yan Hu,jzhao@buaa.edu.cn

期刊论文

Numerical analysis of aerodynamic noise radiated from cross flow fan

CHEN Anbang, LI Song, HUANG Dongtao

期刊论文

Air-borne noise of thermal module and system for notebook personal computers: experimental study

SHI Junye, JIANG Cailing, QIAO Junsheng, CHEN Jiangpin, LI Xiaoping, ZHANG Xiaojun

期刊论文

基于位置旋转变换和非均匀快速傅立叶变换的机动目标高效相参检测

靳科1,赖涛2,齐艳丽3,黄洁1,赵拥军1

期刊论文