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关键词

临震信号 3

噪声 2

振动信号 2

3D打印 1

AD9954 1

AR模型 1

BPSK 1

CFD 1

CMOS；跨导提升技术；低噪声放大器；变压器；共栅级 1

CO2管道；离岸CCUS；海底管道；管道腐蚀；管道断裂；泄漏监测 1

CP）；符号间干扰（inter symbol interference， ISI）；载波间干扰（inter carrier interference 1

Cuk矩阵变换器 1

DPP）；分布式功率转换器；开关电容转换器 1

FGR预测 1

ICI）；最大似然估计（maximum likelihood estimation 1

MLE） 1

MPPT）；差分功率处理（Differential power processing 1

Mie散射 1

N∶P比值 1

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Adaptive robust beamformer formulti-pair two-way relay networks with imperfect channel state information

Jin WANG,Feng SHU,Ri-qing CHEN,Yu-di CUI,Yu CHEN,Jun LI

《信息与电子工程前沿（英文）》 2016年 第17卷 第3期   页码 265-280 doi: 10.1631/FITEE.1500134

摘要： In wideband multi-pair two-way relay networks, the performance of beamforming at a relay station (RS) is intimately related to the accuracy of the channel state information (CSI) available. The accuracy of CSI is determined by Doppler spread, delay between beamforming and channel estimation, and density of pilot symbols, including transmit power of pilot symbols. The coefficient of the Gaussian-Markov CSI error model is modeled as a function of CSI delay, Doppler spread, and signal-to-noise ratio, and can be estimated in real time. In accordance with the real-time estimated coefficients of the error model, an adaptive robust maximum signal-to-interferenceand- noise ratio (Max-SINR) plus maximum signal-to-leakage-and-noise ratio (Max-SLNR) beamformer at an RS is proposed to track the variation of the CSI error. From simulation results and analysis, it is shown that: compared to existing non-adaptive beamformers, the proposed adaptive beamformer is more robust and performs much better in the sense of bit error rate (BER); with increase in the density of transmit pilot symbols, its BER and sum-rate performances tend to those of the beamformer of Max-SINR plus Max-SLNR with ideal CSI.

关键词： Multi-pair two-way relay     Adaptive robust beamformer     Channel state information (CSI)     Maximum signal-to-interference-and-noise ratio (Max-SINR)     Maximum signal-to-leakage-and-noise ratio (Max-SLNR)    

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Target tracking methods based on a signal-to-noise ratio model

Dai Liu, Yong-bo Zhao, Zi-qiao Yuan, Jie-tao Li, Guo-ji Chen,ybzhao@xidian.edu.cn

《信息与电子工程前沿（英文）》 2020年 第21卷 第12期   页码 1671-1814 doi: 10.1631/FITEE.1900679

摘要： In traditional methods, the and are often measured by the empirical value, while observation noise is a constant. In this paper, the and are analyzed. They are influenced by the signal-to-noise ratio (SNR). Therefore, a model related to SNR has been established, in which the SNR information is applied for . Combined with an advanced method, the extended Kalman filter method based on the SNR model (SNR-EKF) and the unscented Kalman filter method based on the SNR model (SNR-UKF) are proposed. There is little difference between the SNR-EKF and SNR-UKF methods in position precision, but the SNR-EKF method has advantages in computation time and the SNR-UKF method has advantages in velocity precision. Simulation results show that methods based on the SNR model can greatly improve the tracking performance compared with traditional tracking methods. The accuracy and convergence speed of the proposed methods have significant improvements.
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提高地下金属管振动波测试中冲击响应信号的信噪比

韩修廷,王洁春,焦振强,高飞,宋宇波

《中国工程科学》 2005年 第7卷 第10期   页码 64-68

摘要：

提出了在套损振动波检测过程中提高信号信噪比的方法。检测过程中，在井口敲击套管并接收、分析套管的回波，以了解介质的变化情况。由于反射波信号强度较微弱，单纯用一组接收信号无法进行正确的套损分析，采用信号增强方法，即利用多个类似信号进行叠加，增强反射波的有效信号，降低背景噪声，从而得到有用信息，进行正确的套损状况分析。开发了相应的信号处理软件，提高了信号处理速度。通过10井次的测试表明，技术原理可行，软件工作稳定、可靠，便于操作，可以进行多种方法的信号处理，极大地提高了工作效率。

关键词： 振动波     反射波     信号增强     信号叠加    

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Controlling interstory drift ratio profiles via topology optimization strategies

《结构与土木工程前沿（英文）》 2023年 第17卷 第2期   页码 165-178 doi: 10.1007/s11709-022-0892-3

摘要： An approach to control the profiles of interstory drift ratios along the height of building structures via topology optimization is proposed herein. The theoretical foundation of the proposed approach involves solving a min–max optimization problem to suppress the maximum interstory drift ratio among all stories. Two formulations are suggested: one inherits the bound formulation and the other utilizes a p-norm function to aggregate all individual interstory drift ratios. The proposed methodology can shape the interstory drift ratio profiles into inverted triangular or quadratic patterns because it realizes profile control using a group of shape weight coefficients. The proposed formulations are validated via a series of numerical examples. The disparity between the two formulations is clear. The optimization results show the optimal structural features for controlling the interstory drift ratios under different requirements.

关键词： interstory drift ratio     aggregation function     bound formulation     min–max problem     topology optimization    

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微地震监测技术探究

唐春华,顾广庆

《中国工程科学》 2012年 第14卷 第4期   页码 95-99

摘要：

微地震监测是地球物理学中的一个重要研究方向，它在油田勘探开采等众多领域有广泛的应用。从微地震的形成机理出发，介绍了微地震的发展历程。重点讨论了微地震监测系统的重要组成部分、关键技术和微地震监测的具体实施，最后讨论了微地震未来的发展与趋势。

关键词： 微地震监测     水力压裂     石油天然气     信噪比     事件定位    

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基于特征分析和最大信干噪比波束形成器的鲁棒广义旁瓣消除器 Research Articles

Quan-dong WANG, Liang-hao GUO, Wei-yu ZHANG, Sui-ling REN, Chao YAN

《信息与电子工程前沿（英文）》 2019年 第20卷 第7期   页码 975-987 doi: 10.1631/FITEE.1700367

摘要： 提出一种鲁棒的广义旁瓣消除器抵抗到达方向失配的影响。为估计干扰加噪声的统计特性，传统信号提取方法常需收集大量仅存在干扰噪声的信号片段。为避免该收集过程，我们使用特征分析方法重新设计阻塞矩阵结构，从接收样本中重建干扰噪声的协方差矩阵。另外，基于秩-1矩阵假设，改进特征分析重建方法，以实现更高重建精度。将该重建方法与最大信干噪声比波束形成器结合，获得阻塞矩阵，最大限度减少信号泄漏的影响，并最大化干扰噪声功率，以进一步在最终输出中抑制噪声和干扰成分。数值结果表明，在存在到达方向失配和快照数有限的情况下，上述两种方法在输出波形信干噪比和与期望信号的相关系数方面有显著改进。与所提第一种方法相比，改进后的方法可进一步减少信号失真。

关键词： 特征分析；干扰噪声协方差矩阵重建；最大信干噪比准则；阻塞矩阵；广义旁瓣消除器；到达方向失配    

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High-order phase-field model with the local and second-order max-entropy approximants

Fatemeh AMIRI

《结构与土木工程前沿（英文）》 2019年 第13卷 第2期   页码 406-416 doi: 10.1007/s11709-018-0475-5

摘要： We approximate the fracture surface energy functional based on phase-field method with smooth local maximum entropy (LME) and second-order maximum entropy (SME) approximants. The higher-order continuity of the meshfree methods such as LME and SME approximants allows to directly solve the fourth-order phase-field equations without splitting the fourth-order differential equation into two second-order differential equations. We will first show that the crack surface functional can be captured more accurately in the fourth-order model with smooth approximants such as LME, SME and B-spline. Furthermore, smaller length scale parameter is needed for the fourth-order model to approximate the energy functional. We also study SME approximants and drive the formulations. The proposed meshfree fourth-order phase-field formulation show more stable results for SME compared to LME meshfree methods.

关键词： second-order maximum entropy     local maximum entropy     second- and fourth-order phase-field models     B-spline    

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Process improvement in laser hot wire cladding for martensitic stainless steel based on the Taguchi method

Zilin HUANG,Gang WANG,Shaopeng WEI,Changhong LI,Yiming RONG

《机械工程前沿（英文）》 2016年 第11卷 第3期   页码 242-249 doi: 10.1007/s11465-016-0397-7

摘要：

Laser hot wire cladding, with the prominent features of low heat input, high energy efficiency, and high precision, is widely used for remanufacturing metal parts. The cladding process, however, needs to be improved by using a quantitative method. In this work, volumetric defect ratio was proposed as the criterion to describe the integrity of forming quality for cladding layers. Laser deposition experiments with FV520B, one of martensitic stainless steels, were designed by using the Taguchi method. Four process variables, namely, laser power (P), scanning speed (Vs), wire feed rate (Vf), and wire current (I), were optimized based on the analysis of signal-to-noise (S/N) ratio. Metallurgic observation of cladding layer was conducted to compare the forming quality and to validate the analysis method. A stable and continuous process with the optimum parameter combination produced uniform microstructure with minimal defects and cracks, which resulted in a good metallurgical bonding interface.

关键词： process optimization     Taguchi method     signal-to-noise (S/N) ratio     volumetric defect ratio     laser hot wire cladding    

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Overlap maximum matching ratio (OMMR): a new measure to evaluate overlaps of essential modules

Xiao-xia ZHANG,Qiang-hua XIAO,Bin LI,Sai HU,Hui-jun XIONG,Bi-hai ZHAO

《信息与电子工程前沿（英文）》 2015年 第16卷 第4期   页码 293-300 doi: 10.1631/FITEE.1400282

摘要： Protein complexes are the basic units of macro-molecular organizations and help us to understand the cell’s mechanism. The development of the yeast two-hybrid, tandem affinity purification, and mass spectrometry high-throughput proteomic techniques supplies a large amount of protein-protein interaction data, which make it possible to predict overlapping complexes through computational methods. Research shows that overlapping complexes can contribute to identifying essential proteins, which are necessary for the organism to survive and reproduce, and for life’s activities. Scholars pay more attention to the evaluation of protein complexes. However, few of them focus on predicted overlaps. In this paper, an evaluation criterion called overlap maximum matching ratio (OMMR) is proposed to analyze the similarity between the identified overlaps and the benchmark overlap modules. Comparison of essential proteins and gene ontology (GO) analysis are also used to assess the quality of overlaps. We perform a comprehensive comparison of serveral overlapping complexes prediction approaches, using three yeast protein-protein interaction (PPI) networks. We focus on the analysis of overlaps identified by these algorithms. Experimental results indicate the important of overlaps and reveal the relationship between overlaps and identification of essential proteins.

关键词： Protein-protein interaction network     Essential protein modules     Overlap     Overlap maximum matching ratio    

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Numerical and experimental analyses of methane leakage in shield tunnel

《结构与土木工程前沿（英文）》   页码 1011-1020 doi: 10.1007/s11709-023-0956-z

摘要： Tunnels constructed in gas-bearing strata are affected by the potential leakage of harmful gases, such as methane gas. Based on the basic principles of computational fluid dynamics, a numerical analysis was performed to simulate the ventilation and diffusion of harmful gases in a shield tunnel, and the effect of ventilation airflow speed on the diffusion of harmful gases was evaluated. As the airflow speed increased from 1.8 to 5.4 m/s, the methane emission was diluted, and the methane accumulation was only observed in the area near the methane leakage channels. The influence of increased ventilation airflow velocity was dominant for the ventilation modes with two and four fans. In addition, laboratory tests on methane leakage through segment joints were performed. The results show that the leakage process can be divided into “rapid leakage” and “slight leakage”, depending on the leakage pressure and the state of joint deformation. Based on the numerical and experimental analysis results, a relationship between the safety level and the joint deformation is established, which can be used as guidelines for maintaining utility tunnels.

关键词： shield tunnel     harmful gas leakage     numerical analysis     laboratory test    

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De-noising of diesel vibration signal using wavelet packet and singular value decomposition

DUAN Li-xiang, ZHANG Lai-bin, WANG Zhao-hui

《机械工程前沿（英文）》 2006年 第1卷 第4期   页码 443-447 doi: 10.1007/s11465-006-0055-6

摘要： The vibration signals of diesel include excess noise that must be eliminated before extraction of characteristic parameters. Firstly, the effects of vibration-signal de-noising among Fourier transform, wavelet decomposition and wavelet packet decomposition are compared. Secondly, singular value decomposition is applied to de-noising vibration signals. Finally, a new de-noise method integrated with wavelet packet and singular value is presented. In this method, vibration signals are decomposed by wavelet packet, and the wavelet packet coefficient is de-noised by singular value decomposition again. The results indicate that the new de-noising method is the best. The SNR (signal-to-noise ratio) of the vibration signals of a diesel cylinder lid is the highest. The diesel vibration waveforms of combustion and valve become clear and the extracted characteristic parameters become more precise.

关键词： coefficient     de-noised     cylinder     signal-to-noise     wavelet decomposition    

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Destructive and non-destructive evaluation of concrete for optimum sand to aggregate volume ratio

《结构与土木工程前沿（英文）》 2021年 第15卷 第6期   页码 1400-1414 doi: 10.1007/s11709-021-0779-8

摘要： Aggregates are the biggest contributor to concrete volume and are a crucial parameter in dictating its mechanical properties. As such, a detailed experimental investigation was carried out to evaluate the effect of sand-to-aggregate volume ratio (s/a) on the mechanical properties of concrete utilizing both destructive and non-destructive testing (employing UPV (ultrasonic pulse velocity) measurements). For investigation, standard cylindrical concrete samples were made with different s/a (0.36, 0.40, 0.44, 0.48, 0.52, and 0.56), cement content (340 and 450 kg/m3), water-to-cement ratio (0.45 and 0.50), and maximum aggregate size (12 and 19 mm). The effect of these design parameters on the 7, 14, and 28 d compressive strength, tensile strength, elastic modulus, and UPV of concrete were assessed. The careful analysis demonstrates that aggregate proportions and size need to be optimized for formulating mix designs; optimum ratios of s/a were found to be 0.40 and 0.44 for the maximum aggregate size of 12 and 19 mm, respectively, irrespective of the W/C (water-to-cement) and cement content.

关键词： aggregates     non-destructive testing     sand-to-aggregate volume ratio (s/a)     maximum aggregate size (MAS)    

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波音737 Max Saga——自动化缺陷

Chris Palmer

《工程（英文）》 2020年 第6卷 第1期   页码 2-3 doi: 10.1016/j.eng.2019.11.002

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基于经验模式分解的旋转机械振动信号降噪处理

杨建文,贾民平,许飞云,胡建中

《中国工程科学》 2005年 第7卷 第8期   页码 66-69

摘要：

分析了经验模式分解的滤波性能；针对旋转机械振动信号信噪比低及非平稳特性，应用经验模式分解对振动信号进行降噪处理，突出了有用振动信号，为旋转机械在线监测和故障诊断提供了有效的依据；仿真实验及真实数据分析表明，经验模式分解在振动信号降噪处理中是有效的，为振动信号分析提供了新的方法。

关键词： 故障诊断     经验模式分解     旋转机械     滤波    

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Wavelet-based iterative data enhancement for implementation in purification of modal frequency for extremely noisy ambient vibration tests in Shiraz-Iran

Hassan YOUSEFI, Alireza TAGHAVI KANI, Iradj MAHMOUDZADEH KANI, Soheil MOHAMMADI

《结构与土木工程前沿（英文）》 2020年 第14卷 第2期   页码 446-472 doi: 10.1007/s11709-019-0605-8

摘要： The main purpose of the present study is to enhance high-level noisy data by a wavelet-based iterative filtering algorithm for identification of natural frequencies during ambient wind vibrational tests on a petrochemical process tower. Most of denoising methods fail to filter such noise properly. Both the signal-to-noise ratio and the peak signal-to-noise ratio are small. Multiresolution-based one-step and variational-based filtering methods fail to denoise properly with thresholds obtained by theoretical or empirical method. Due to the fact that it is impossible to completely denoise such high-level noisy data, the enhancing approach is used to improve the data quality, which is the main novelty from the application point of view here. For this iterative method, a simple computational approach is proposed to estimate the dynamic threshold values. Hence, different thresholds can be obtained for different recorded signals in one ambient test. This is in contrast to commonly used approaches recommending one global threshold estimated mainly by an empirical method. After the enhancements, modal frequencies are directly detected by the cross wavelet transform (XWT), the spectral power density and autocorrelation of wavelet coefficients. Estimated frequencies are then compared with those of an undamaged-model, simulated by the finite element method.

关键词： ambient vibration test     high level noise     iterative signal enhancement     wavelet     cross and autocorrelation of wavelets    

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标题 作者 时间 类型 操作

Adaptive robust beamformer formulti-pair two-way relay networks with imperfect channel state information

Jin WANG,Feng SHU,Ri-qing CHEN,Yu-di CUI,Yu CHEN,Jun LI

期刊论文

Target tracking methods based on a signal-to-noise ratio model

Dai Liu, Yong-bo Zhao, Zi-qiao Yuan, Jie-tao Li, Guo-ji Chen,ybzhao@xidian.edu.cn

期刊论文

提高地下金属管振动波测试中冲击响应信号的信噪比

韩修廷,王洁春,焦振强,高飞,宋宇波

期刊论文

Controlling interstory drift ratio profiles via topology optimization strategies

期刊论文

微地震监测技术探究

唐春华,顾广庆

期刊论文

基于特征分析和最大信干噪比波束形成器的鲁棒广义旁瓣消除器

Quan-dong WANG, Liang-hao GUO, Wei-yu ZHANG, Sui-ling REN, Chao YAN

期刊论文

High-order phase-field model with the local and second-order max-entropy approximants

Fatemeh AMIRI

期刊论文

Process improvement in laser hot wire cladding for martensitic stainless steel based on the Taguchi method

Zilin HUANG,Gang WANG,Shaopeng WEI,Changhong LI,Yiming RONG

期刊论文

Overlap maximum matching ratio (OMMR): a new measure to evaluate overlaps of essential modules

Xiao-xia ZHANG,Qiang-hua XIAO,Bin LI,Sai HU,Hui-jun XIONG,Bi-hai ZHAO

期刊论文

Numerical and experimental analyses of methane leakage in shield tunnel

期刊论文

De-noising of diesel vibration signal using wavelet packet and singular value decomposition

DUAN Li-xiang, ZHANG Lai-bin, WANG Zhao-hui

期刊论文

Destructive and non-destructive evaluation of concrete for optimum sand to aggregate volume ratio

期刊论文

波音737 Max Saga——自动化缺陷

Chris Palmer

期刊论文

基于经验模式分解的旋转机械振动信号降噪处理

杨建文,贾民平,许飞云,胡建中

期刊论文

Wavelet-based iterative data enhancement for implementation in purification of modal frequency for extremely noisy ambient vibration tests in Shiraz-Iran

Hassan YOUSEFI, Alireza TAGHAVI KANI, Iradj MAHMOUDZADEH KANI, Soheil MOHAMMADI

期刊论文