资源类型

期刊论文 64

年份

2023 3

2022 2

2021 3

2020 4

2019 3

2018 3

2017 4

2016 2

2015 10

2014 3

2013 1

2012 1

2011 5

2010 2

2009 1

2008 1

2007 4

2006 3

2005 3

2004 1

展开 ︾

关键词

小波变换 2

物元变换 2

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

HHT 1

Hilbert变换 1

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

MLE） 1

Mallat算法 1

Meyer小波变换 1

OFDM）；快速傅立叶变换（Fast Fourier transform， FFT）；循环前缀（cyclic prefix 1

Walsh循环谱 1

一氧化碳氧化 1

严格雪崩准则 1

中轴变换；包络；插值；蒙皮；圆 1

信号处理 1

傅立叶红外光谱 1

傅里叶变换 1

傅里叶变换红外成像 1

内积变换原理 1

展开 ︾

检索范围：

排序： 展示方式：

A reversibility-gain model for integer Karhunen-Loève transform design in video coding

Xing-guo ZHU,Lu YU

《信息与电子工程前沿（英文）》 2015年 第16卷 第10期   页码 883-891 doi: 10.1631/FITEE.1500071

摘要： Karhunen-Loève transform (KLT) is the optimal transform that minimizes distortion at a given bit allocation for Gaussian source. As a KLT matrix usually contains non-integers, integer-KLT design is a classical problem. In this paper, a joint reversibility-gain (R-G) model is proposed for integer-KLT design in video coding. Specifically, the ‘reversibility’ is modeled according to distortion analysis in using forward and inverse integer transform without quantization. It not only measures how invertible a transform is, but also bounds the distortion introduced by the non-orthonormal integer transform process. The ‘gain’ means transform coding gain (TCG), which is a widely used criterion for transform design in video coding. Since KLT maximizes the TCG under some assumptions, here we define the TCG loss ratio (LR) to measure how much coding gain an integer-KLT loses when compared with the original KLT. Thus, the R-G model can be explained as follows: subject to a certain TCG LR, an integer-KLT with the best reversibility is the optimal integer transform for a given non-integer-KLT. Experimental results show that the R-G model can guide the design of integer-KLTs with good performance.

关键词： Integer transform     Karhunen-Loè     ve transform (KLT)     Integer-KLT     Transform coding     Video coding    

HTML PDF 收藏

Treatment, residual chlorine and season as factors affecting variability of trihalomethanes in small drinking water systems

Roberta DYCK,Geneviève COOL,Manuel RODRIGUEZ,Rehan SADIQ

《环境科学与工程前沿（英文）》 2015年 第9卷 第1期   页码 171-179 doi: 10.1007/s11783-014-0750-1

摘要： Seasonal variability in source water can lead to challenges for drinking water providers related to operational optimization and process control in treatment facilities. The objective of this study is to investigate seasonal variability of water quality in municipal small water systems (<3000 residents) supplied by surface waters. Residual chlorine and trihalomethanes (THM) were measured over seven years (2003–2009). Comparisons are made within each system over time, as well as between systems according to the type of their treatment technologies. THM concentrations are generally higher in the summer and autumn. The seasonal variability was generally more pronounced in systems using chlorination plus additional treatment. Chloroform, total THM (TTHM) and residual chlorine concentrations were generally lower in systems using chlorination plus additional treatment. Conversely, brominated THM concentrations were higher in systems using additional treatment. Residual chlorine was highest in the winter and lowest in the spring and summer. Seasonal variations were most pronounced for residual chlorine in systems with additional treatment. There was generally poor correlation between THM concentrations and concentrations of residual chlorine. Further study with these data will be beneficial in finding determinants and indicators for both quantity and variability of disinfection byproducts and other water quality parameters.

关键词： drinking water     residual chlorine     seasonal variability     small municipal systems     treatment technologies     trihalomethanes    

HTML PDF 收藏

Identification of faults through wavelet transform vis-à-vis fast Fourier transform of noisy vibration

null

《机械工程前沿（英文）》 2014年 第9卷 第2期   页码 130-141 doi: 10.1007/s11465-014-0298-6

摘要：

Fault diagnosis of rolling element bearings requires efficient signal processing techniques. For this purpose, the performances of envelope detection with fast Fourier transform (FFT) and continuous wavelet transform (CWT) of vibration signals produced from a bearing with defects on inner race and rolling element, have been examined at low signal to noise ratio. Both simulated and experimental signals from identical bearings have been considered for the purpose of analysis. The bearings have been modeled as spring-mass-dashpot systems and the simulated signals have been obtained considering transfer functions for the bearing systems subjected to impulsive loads due to the defects. Frequency B spline wavelets have been applied for CWT and a discussion on wavelet selection has been presented for better effectiveness. Results show that use of CWT with the proposed wavelets overcomes the short coming of FFT while processing a noisy vibration signals for defect detection of bearings.

关键词： Fault detection     spline wavelet     continuous wavelet transform     fast Fourier transform    

HTML PDF 收藏

Molecular dynamics simulations of initial Pd and PdO nanocluster growth in a magnetron gas aggregation source

Pascal Brault, William Chamorro-Coral, Sotheara Chuon, Amaël Caillard, Jean-Marc Bauchire, Stève Baranton

《化学科学与工程前沿（英文）》 2019年 第13卷 第2期   页码 324-329 doi: 10.1007/s11705-019-1792-5

摘要： Molecular dynamics simulations are carried out for describing growth of Pd and PdO nanoclusters using the ReaxFF force field. The resulting nanocluster structures are successfully compared to those of nanoclusters experimentally grown in a gas aggregation source. The PdO structure is quasi-crystalline as revealed by high resolution transmission microscope analysis for experimental PdO nanoclusters. The role of the nanocluster temperature in the molecular dynamics simulated growth is highlighted.

关键词： molecular dynamics     cluster growth     plasma sputtering     nanocatalyst    

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

Thermogravimetric coupled with Fourier transform infrared analysis study on thermal treatment of monopotassium

Yuheng FENG, Xuguang JIANG, Yong CHI, Xiaodong LI, Hongmei ZHU

《环境科学与工程前沿（英文）》 2011年 第5卷 第2期   页码 186-192 doi: 10.1007/s11783-011-0322-6

摘要： In China, safe disposal of hazardous waste is more and more a necessity, urged by rapid economic development. The pyrolysis and combustion characteristics of a residue from producing monopotassium phosphate (monopotassium phosphate residue), considered as a hazardous waste, were studied using a thermogravimetric, coupled with Fourier transform infrared analyzer (TG-FTIR). Both pyrolysis and combustion runs can be subdivided into three stages: drying, thermal decomposition, and final devolatilization. The average weight loss rate during fast thermal decomposition stage in pyrolysis is higher than combustion. Acetic acid, methane, pentane, (acetyl) cyclopropane, 2,4,6-trichlorophenol, CO, and CO were distinguished in the pyrolysis process, while CO was the dominant combustion product.

关键词： hazardous waste     combustion     pyrolysis     thermogravimetric coupled with Fourier transform infrared analysis (TG-FTIR)     monopotassium phosphate residue    

HTML PDF 收藏

稀疏快速Clifford傅里叶变换 Article

Rui WANG, Yi-xuan ZHOU, Yan-liang JIN, Wen-ming CAO

《信息与电子工程前沿（英文）》 2017年 第18卷 第8期   页码 1131-1141 doi: 10.1631/FITEE.1500452

摘要： Clifford傅里叶变换（Clifford Fourier transform, CFT）可以应用于矢量场和标量场，但无法有效解决大数据问题，因为该算法是基于每个信号量计算的。稀疏快速傅里叶变换（sparse fast Fourier transform, sFFT）理论通过选择性地使用输入数据来处理大数据问题。

关键词： 稀疏快速傅里叶变换（sFFT）；Clifford傅里叶变换（CFT）；稀疏快速Clifford傅里叶变换（SFCFT）；Clifford代数    

HTML PDF 收藏

A new acoustic emission source location technique based on wavelet transform and mode analysis

JIAO Jing-pin, HE Cun-fu, WU Bin, FEI Ren-yuan, WANG Xiu-yan

《机械工程前沿（英文）》 2006年 第1卷 第3期   页码 341-345 doi: 10.1007/s11465-006-0006-4

摘要： For wave propagation in dispersive media, the arrival time of the acoustic emission signal to the sensor is dependent on the setting of the threshold voltage, which results in the inaccuracy of the acoustic emission location. Based on the wavelet transform and the theory of modal acoustic emission, a new method is proposed to improve the accuracy of acoustic emission source location. It is believed that the acoustic emission signal propagation in the structure has the characteristics of multi-mode and dispersion, and the acoustic emission source location should use the arrival time to sensors obtained from the output signals not only at the same mode but also at the same frequency. The wavelet transform is used to resolve the problem. By utilizing the time-frequency data of the wavelet, the frequency-dependent arrival time traveling is easily obtained; by numerical computation of the wave s propagation in structure, the group velocity of the guided mode is also obtained, therefore the accuracy source location is realized. The acoustic emission source location experiments were conducted in a thin steel plate and results show that the technique is an effective tool for acoustic emission source location.

关键词： s propagation     frequency     emission signal     signal propagation     dispersive    

HTML PDF 收藏

Non-stationary signal analysis based on general parameterized time--frequency transform and its application

Peng ZHOU, Zhike PENG, Shiqian CHEN, Yang YANG, Wenming ZHANG

《机械工程前沿（英文）》 2018年 第13卷 第2期   页码 292-300 doi: 10.1007/s11465-017-0443-0

摘要：

With the development of large rotary machines for faster and more integrated performance, the condition monitoring and fault diagnosis for them are becoming more challenging. Since the time-frequency (TF) pattern of the vibration signal from the rotary machine often contains condition information and fault feature, the methods based on TF analysis have been widely-used to solve these two problems in the industrial community. This article introduces an effective non-stationary signal analysis method based on the general parameterized time–frequency transform (GPTFT). The GPTFT is achieved by inserting a rotation operator and a shift operator in the short-time Fourier transform. This method can produce a high-concentrated TF pattern with a general kernel. A multi-component instantaneous frequency (IF) extraction method is proposed based on it. The estimation for the IF of every component is accomplished by defining a spectrum concentration index (SCI). Moreover, such an IF estimation process is iteratively operated until all the components are extracted. The tests on three simulation examples and a real vibration signal demonstrate the effectiveness and superiority of our method.

关键词： rotary machines     condition monitoring     fault diagnosis     GPTFT     SCI    

HTML PDF 收藏

Real time monitoring of bioreactor mAb IgG3 cell culture process dynamics via Fourier transform infrared

Huiquan Wu, Erik Read, Maury White, Brittany Chavez, Kurt Brorson, Cyrus Agarabi, Mansoor Khan

《化学科学与工程前沿（英文）》 2015年 第9卷 第3期   页码 386-406 doi: 10.1007/s11705-015-1533-3

摘要： Compared to small molecule process analytical technology (PAT) applications, biotechnology product PAT applications have certain unique challenges and opportunities. Understanding process dynamics of bioreactor cell culture process is essential to establish an appropriate process control strategy for biotechnology product PAT applications. Inline spectroscopic techniques for real time monitoring of bioreactor cell culture process have the distinct potential to develop PAT approaches in manufacturing biotechnology drug products. However, the use of inline Fourier transform infrared (FTIR) spectroscopic techniques for bioreactor cell culture process monitoring has not been reported. In this work, real time inline FTIR Spectroscopy was applied to a lab scale bioreactor mAb IgG3 cell culture fluid biomolecular dynamic model. The technical feasibility of using FTIR Spectroscopy for real time tracking and monitoring four key cell culture metabolites (including glucose, glutamine, lactate, and ammonia) and protein yield at increasing levels of complexity (simple binary system, fully formulated media, actual bioreactor cell culture process) was evaluated via a stepwise approach. The FTIR fingerprints of the key metabolites were identified. The multivariate partial least squares (PLS) calibration models were established to correlate the process FTIR spectra with the concentrations of key metabolites and protein yield of in-process samples, either individually for each metabolite and protein or globally for all four metabolites simultaneously. Applying the 2 derivative pre-processing algorithm to the FTIR spectra helps to reduce the number of PLS latent variables needed significantly and thus simplify the interpretation of the PLS models. The validated PLS models show promise in predicting the concentration profiles of glucose, glutamine, lactate, and ammonia and protein yield over the course of the bioreactor cell culture process. Therefore, this work demonstrated the technical feasibility of real time monitoring of the bioreactor cell culture process via FTIR spectroscopy. Its implications for enabling cell culture PAT were discussed.

关键词： process analytical technology (PAT)     Fourier-transform infrared (FTIR) spectroscopy     partial least squares (PLS) regression     mouse IgG3     bioreactor cell culture process     real time process monitoring    

HTML PDF 收藏

基于HHT的泄流结构损伤在线监测方法研究

练继建,李成业,刘昉,马斌

《中国工程科学》 2011年 第13卷 第12期   页码 38-44

摘要：

结合HHT方法在描述信号瞬时特性和信号处理方面的独特优势，提出了一种基于HHT的泄流结构损伤实时监测诊断方法。首先，利用信号能量谱构造能量分布向量ηi，进而定义结构异常指标和预警指数，最后通过计算相邻时间段内的异常指标，实现结构损伤的在线监测。应用文中方法对一导墙结构进行数值仿真试验，结果表明，文章中定义的异常指标能够较准确地判断结构的损伤，同时具有一定的抗噪能力。

关键词： 泄流结构     HHT     能量分布向量     异常指标     预警指数     数值仿真    

HTML PDF 收藏

Probabilistic stability of uncertain composite plates and stochastic irregularity in their buckling mode shapes: A semi-analytical non-intrusive approach

《结构与土木工程前沿（英文）》   页码 179-190 doi: 10.1007/s11709-022-0888-z

摘要： In this study, the mechanical properties of the composite plate were considered Gaussian random fields and their effects on the buckling load and corresponding mode shapes were studied by developing a semi-analytical non-intrusive approach. The random fields were decomposed by the Karhunen−Loève method. The strains were defined based on the assumptions of the first-order and higher-order shear-deformation theories. Stochastic equations of motion were extracted using Euler–Lagrange equations. The probabilistic response space was obtained by employing the non-intrusive polynomial chaos method. Finally, the effect of spatially varying stochastic properties on the critical load of the plate and the irregularity of buckling mode shapes and their sequences were studied for the first time. Our findings showed that different shear deformation plate theories could significantly influence the reliability of thicker plates under compressive loading. It is suggested that a linear relationship exists between the mechanical properties’ variation coefficient and critical loads’ variation coefficient. Also, in modeling the plate properties as random fields, a significant stochastic irregularity is obtained in buckling mode shapes, which is crucial in practical applications.

关键词： uncertain composite plate     stochastic assume mode method     Karhunen−Loève theorem     polynomial chaos approach     plate buckling     irregularity in buckling mode shapes    

HTML PDF 收藏

Subspace transform induced robust similarity measure for facial images

Jian Zhang, Heng Zhang, Li-ling Bo, Hong-ran Li, Shuai Xu, Dong-qing Yuan,zhangjian@jou.edu.cn,zhangheng@jou.edu.cn

《信息与电子工程前沿（英文）》 2020年 第21卷 第9期   页码 1267-1412 doi: 10.1631/FITEE.1900552

摘要： Similarity measure has long played a critical role and attracted great interest in various areas such as and machine perception. Nevertheless, there remains the issue of developing an efficient two-dimensional (2D) robust similarity measure method for images. Inspired by the properties of subspace, we develop an effective 2D technique, named transformation similarity measure (TSM), for robust . Specifically, the TSM method robustly determines the similarity between two well-aligned frontal facial images while weakening interference in the by linear transformation and singular value decomposition. We present the mathematical features and some odds to reveal the feasible and robust measure mechanism of TSM. The performance of the TSM method, combined with the nearest neighbor rule, is evaluated in under different challenges. Experimental results clearly show the advantages of the TSM method in terms of accuracy and robustness.
HTML PDF 收藏

可拓检测技术

余永权

《中国工程科学》 2001年 第3卷 第4期   页码 88-94

摘要：

检测技术是目前多种学科的关键技术，检测中有两个难题：一个是无法检测的问题，另一个是检测精度提高的问题。基于可拓学矛盾转化的思想方法，提出了一种与传统检测技术不同的新技术--可拓检测，这种检测技术利用可拓学的物元概念及相关方法，从矛盾转化去研究检测技术，以解决无法检测的物理量检测问题。文章给出了可拓检测的有关概念，基本原理及结构，并且提出了有关的实施方法和应用实例。

关键词： 可拓检测     可拓学     物元变换    

HTML PDF 收藏

一种快速均匀的采用尺度不变特征变换描述符进行基于内容的卫星图像配准方法 Article

Hamed BOZORGI, Ali JAFARI

《信息与电子工程前沿（英文）》 2017年 第18卷 第8期   页码 1108-1116 doi: 10.1631/FITEE.1500295

摘要： 尺度不变特征变换（scale-invariant feature transform, SIFT）算法是一种成功应用于卫星图像配准的算法。本地SIFT描述符被许多研究者应用于改进图像检索流程。

关键词： 基于内容的卫星图像配准；特征点分布；图像配准；线性判别准则；遥感；尺度不变特征变换    

HTML PDF 收藏

标题 作者 时间 类型 操作

A reversibility-gain model for integer Karhunen-Loève transform design in video coding

Xing-guo ZHU,Lu YU

期刊论文

Treatment, residual chlorine and season as factors affecting variability of trihalomethanes in small drinking water systems

Roberta DYCK,Geneviève COOL,Manuel RODRIGUEZ,Rehan SADIQ

期刊论文

Identification of faults through wavelet transform vis-à-vis fast Fourier transform of noisy vibration

null

期刊论文

Molecular dynamics simulations of initial Pd and PdO nanocluster growth in a magnetron gas aggregation source

Pascal Brault, William Chamorro-Coral, Sotheara Chuon, Amaël Caillard, Jean-Marc Bauchire, Stève Baranton

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

Thermogravimetric coupled with Fourier transform infrared analysis study on thermal treatment of monopotassium

Yuheng FENG, Xuguang JIANG, Yong CHI, Xiaodong LI, Hongmei ZHU

期刊论文

稀疏快速Clifford傅里叶变换

Rui WANG, Yi-xuan ZHOU, Yan-liang JIN, Wen-ming CAO

期刊论文

A new acoustic emission source location technique based on wavelet transform and mode analysis

JIAO Jing-pin, HE Cun-fu, WU Bin, FEI Ren-yuan, WANG Xiu-yan

期刊论文

Non-stationary signal analysis based on general parameterized time--frequency transform and its application

Peng ZHOU, Zhike PENG, Shiqian CHEN, Yang YANG, Wenming ZHANG

期刊论文

Real time monitoring of bioreactor mAb IgG3 cell culture process dynamics via Fourier transform infrared

Huiquan Wu, Erik Read, Maury White, Brittany Chavez, Kurt Brorson, Cyrus Agarabi, Mansoor Khan

期刊论文

基于HHT的泄流结构损伤在线监测方法研究

练继建,李成业,刘昉,马斌

期刊论文

Probabilistic stability of uncertain composite plates and stochastic irregularity in their buckling mode shapes: A semi-analytical non-intrusive approach

期刊论文

Subspace transform induced robust similarity measure for facial images

Jian Zhang, Heng Zhang, Li-ling Bo, Hong-ran Li, Shuai Xu, Dong-qing Yuan,zhangjian@jou.edu.cn,zhangheng@jou.edu.cn

期刊论文

可拓检测技术

余永权

期刊论文

一种快速均匀的采用尺度不变特征变换描述符进行基于内容的卫星图像配准方法

Hamed BOZORGI, Ali JAFARI

期刊论文