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Electromagnetic interference modeling and suppression techniques in variable-frequency drive systems
Le YANG, Shuo WANG, Jianghua FENG
《机械工程前沿(英文)》 2018年 第13卷 第3期 页码 329-353 doi: 10.1007/s11465-018-0466-1
Electromagnetic interference (EMI) causes electromechanical damage to the motors and degrades the reliability of variable-frequency drive (VFD) systems. Unlike fundamental frequency components in motor drive systems, high-frequency EMI noise, coupled with the parasitic parameters of the trough system, are difficult to analyze and reduce. In this article, EMI modeling techniques for different function units in a VFD system, including induction motors, motor bearings, and rectifier-inverters, are reviewed and evaluated in terms of applied frequency range, model parameterization, and model accuracy. The EMI models for the motors are categorized based on modeling techniques and model topologies. Motor bearing and shaft models are also reviewed, and techniques that are used to eliminate bearing current are evaluated. Modeling techniques for conventional rectifier-inverter systems are also summarized. EMI noise suppression techniques, including passive filter, Wheatstone bridge balance, active filter, and optimized modulation, are reviewed and compared based on the VFD system models.
关键词: variable-frequency drive (VFD) electromagnetic interference (EMI) motor drive modeling EMI noise suppression
从中国首台紫外-可见光高光谱卫星仪器反演得到的高空间分辨率臭氧廓线 Article
Fei Zhao, Cheng Liu, Qihou Hu, Congzi Xia, Chengxin Zhang, Wenjing Su
《工程(英文)》 2024年 第32卷 第1期 页码 107-116 doi: 10.1016/j.eng.2023.02.020
Understanding the vertical distribution of ozone is crucial when assessing both its horizontal and vertical transport, as well as when analyzing the physical and chemical properties of the atmosphere. One of the most effective ways to obtain high spatial resolution ozone profiles is through satellite observations. The Environmental Trace Gases Monitoring Instrument (EMI) deployed on the Gaofen-5 satellite is the first Chinese ultraviolet-visible hyperspectral spectrometer. However, retrieving ozone profiles using backscattered radiance values measured by the EMI is challenging due to unavailable measurement errors and a low signal-to-noise ratio. The algorithm developed for the Tropospheric Monitoring Instrument did not allow us to retrieve 87% of the EMI pixels. Therefore, we developed an algorithm specific to the characteristics of the EMI. The fitting residuals are smaller than 0.3% in most regions. The retrieved ozone profiles were in good agreement with ozonesonde data, with maximum mean biases of 20% at five latitude bands. By applying EMI averaging kernels to the ozonesonde profiles, the integrated stratospheric column ozone and tropospheric column ozone also showed excellent agreement with ozonesonde data. The lower layers (0–7.5 km) of the EMI ozone profiles reflected the seasonal variation in surface ozone derived from the China National Environmental Monitoring Center (CNEMC). However, the upper layers (9.7–16.7 km) of the ozone profiles show different trends, with the ozone peak occurring at an altitude of 9.7–16.7 km in March. A stratospheric intrusion event in central China from August 11 to 15, 2019, is captured using the EMI ozone profiles, potential vorticity data, and relative humidity data. The increase in the CNEMC ozone concentration showed that downward transport enhanced surface ozone pollution.
关键词: Ozone profiles EMI Soft calibration Floor noise correction Stratospheric ozone intrusion
Identification of cadmium-induced genes in maize seedlings by suppression subtractive hybridization
Quanlin DAI, Baifei HUANG, Zhongyi YANG, Jiangang YUAN, Junzhi YANG
《环境科学与工程前沿(英文)》 2010年 第4卷 第4期 页码 449-458 doi: 10.1007/s11783-010-0250-x
关键词:
Vibration suppression of speed-controlled robots with nonlinear control
Paolo BOSCARIOL,Alessandro GASPARETTO
《机械工程前沿(英文)》 2016年 第11卷 第2期 页码 204-212 doi: 10.1007/s11465-016-0380-3
In this paper, a simple nonlinear control strategy for the simultaneous position tracking and vibration damping of robots is presented. The control is developed for devices actuated by speed-controlled servo drives. The conditions for the asymptotic stability of the closed-loop system are derived by ensuring its passivity. The capability of achieving improved trajectory tracking and vibration suppression is shown through experimental tests conducted on a three-axis Cartesian robot. The control is aimed to be compatible with most industrial applications given the simplicity of implementation, the reduced computational requirements, and the use of joint position as the only measured signal.
关键词: industrial robot nonlinear control vibration damping model-free control motion control
刘江虹,金翔,廖光煊
《中国工程科学》 2010年 第12卷 第9期 页码 58-62
在研究传统细水雾添加剂的基础上,取长补短,采用物理工艺制备出新型复合添加剂,针对典型火源(酒精池火、煤油池火与木垛火),改变添加剂浓度开展了一系列灭火实验。结果表明:新型复合添加剂显著增强了细水雾的灭火性能,可提高灭火时间5~8倍。随着细水雾中添加剂含量的不断增加,油池火的灭火时间呈现出先快速下降,而后略微增长的趋势;而木垛火的灭火时间表现为平缓下降,并趋于稳定。含新型复合添加剂的细水雾灭火是物理化学复合作用机制,但主导灭火机理是燃料表面的冷却与隔离作用。
A convolutional neural network based approach to sea clutter suppression for small boat detection
Guan-qing Li, Zhi-yong Song, Qiang Fu,liguanqing09@nudt.edu.cn,songzhiyong08@nudt.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.1900523
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
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
Haiqiao WEI, Jie YU, Lei ZHOU
《能源前沿(英文)》 2019年 第13卷 第4期 页码 691-706 doi: 10.1007/s11708-019-0621-3
关键词: high compression ratio knock Miller cycle split injection engine performance
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
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
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
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
关键词: cylinder-shaped evolution computational effective large-scale
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
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
Growth suppression of colorectal cancer expressing S492R EGFR by monoclonal antibody CH12
Qiongna Dong, Bizhi Shi, Min Zhou, Huiping Gao, Xiaoying Luo, Zonghai Li, Hua Jiang
《医学前沿(英文)》 2019年 第13卷 第1期 页码 83-93 doi: 10.1007/s11684-019-0682-z
Colorectal cancer (CRC) is a common malignant tumor in the digestive tract, and 30%–85% of CRCs express epidermal growth factor receptors (EGFRs). Recently, treatments using cetuximab, also named C225, an anti-EGFR monoclonal antibody, for CRC have been demonstrated to cause an S492R mutation in EGFR. However, little is known about the biological function of S492R EGFR. Therefore, we attempted to elucidate its biological function in CRC cells and explore new treatment strategies for this mutant form. Our study indicated that EGFR and S492R EGFR accelerate the growth of CRC cells in vitro and in vivo and monoclonal antibody CH12, which specifically recognizes an EGFR tumor-specific epitope, can bind efficiently to S492R EGFR. Furthermore, mAb CH12 showed significantly stronger growth suppression activities and induced a more potent antibody-dependent cellular cytotoxicity effect on CRC cells bearing S492R EGFR than mAb C225. mAb CH12 obviously suppressed the growth of CRC xenografts with S492R EGFR mutations in vivo. Thus, mAb CH12 may be a promising therapeutic agent in treating patients with CRC bearing an S492R EGFR mutation.
关键词: S492R EGFR ectodomain mutation colorectal cancer mAb CH12 immunnotherapy
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
关键词: bearing dynamical frequency response dynamical simulation hybrid dynamical
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
关键词: tuned mass damper parametric optimization passive control white noise earthquake excitation
标题 作者 时间 类型 操作
Electromagnetic interference modeling and suppression techniques in variable-frequency drive systems
Le YANG, Shuo WANG, Jianghua FENG
期刊论文
从中国首台紫外-可见光高光谱卫星仪器反演得到的高空间分辨率臭氧廓线
Fei Zhao, Cheng Liu, Qihou Hu, Congzi Xia, Chengxin Zhang, Wenjing Su
期刊论文
Identification of cadmium-induced genes in maize seedlings by suppression subtractive hybridization
Quanlin DAI, Baifei HUANG, Zhongyi YANG, Jiangang YUAN, Junzhi YANG
期刊论文
Vibration suppression of speed-controlled robots with nonlinear control
Paolo BOSCARIOL,Alessandro GASPARETTO
期刊论文
A convolutional neural network based approach to sea clutter suppression for small boat detection
Guan-qing Li, Zhi-yong Song, Qiang Fu,liguanqing09@nudt.edu.cn,songzhiyong08@nudt.edu.cn
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
Improvement of engine performance with high compression ratio based on knock suppression using Miller
Haiqiao WEI, Jie YU, Lei ZHOU
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
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
Growth suppression of colorectal cancer expressing S492R EGFR by monoclonal antibody CH12
Qiongna Dong, Bizhi Shi, Min Zhou, Huiping Gao, Xiaoying Luo, Zonghai Li, Hua Jiang
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