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关键词

小波变换 2

快速充电 2

概念设计 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

Cascaded 型检测器 1

DFR 1

FLTD型脉冲加速器 1

HHT 1

Hilbert变换 1

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

MCDB 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

TRIP钢 1

U251细胞 1

Walsh循环谱 1

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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

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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。受之启发，我们提出一个称为稀疏快速Clifford傅里叶变换（sparse fast CFT, SFCFT）的算法，该算法能够大幅度提高在标量场和矢量场中的计算性能。实验对标量场、灰度图和彩色图像数据进行处理，通过与FFT，CFT和sFFT进行比较，表明SFCFT可以有效提升多矢量信号处理的性能。

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

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一种通过循环前缀再利用改善OFDM系统带宽的新型节能ICI消除技术 Article

Sandeep SAROWA, Harmanjeet SINGH, Sunil AGRAWAL, B. S. SOHI

《信息与电子工程前沿（英文）》 2017年第18卷第11期页码 1892-1899 doi: 10.1631/FITEE.1601333

摘要：作为一项非常有前景的技术，正交频分复用（orthogonal frequency division multiplexing, OFDM）解决了频谱分配中的带宽不足问题，引领了无线移动通信领域的发展。然而，多普勒频移和本地振荡器频率同步误差的存在会导致载波间干扰（inter carrier interference, ICI），严重影响了正交频分复用。以往文献中提出了许多ICI消除技术，例如自消除法（self-cancellation, SC），最大似然估计法（maximum likelihood estimation, MLE）和加窗法，但需要在带宽冗余和系统复杂度之间权衡。本文基于接收端循环前缀（cyclic prefix, CP）再利用，提出了一种节能且具有有效带宽的新技术来消除ICI。自消除法和最大似然估计法在发送端发送整个OFDM符号数据时会产生冗余，而本文提出的技术仅使用循环前缀数据（仅占总符号带宽的20％）来估计信道，产生与前两者类似结果的同时节省了大量带宽。仿真结果表明，该技术在误差性能方面有显著的改进；并且在实现高带宽增益的同时，能效也得到了实质性的改善。因此，该技术优于传统ICI消除技术。

关键词：正交频分复用（orthogonal frequency division multiplexing OFDM）；快速傅立叶变换（Fast Fourier transform， FFT）；循环前缀（cyclic

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An improved low-complexity sum-product decoding algorithm for low-density parity-check codes

Michaelraj Kingston ROBERTS,Ramesh JAYABALAN

《信息与电子工程前沿（英文）》 2015年第16卷第6期页码 511-518 doi: 10.1631/FITEE.1400269

摘要： In this paper, an improved low-complexity sum-product decoding algorithm is presented for low-density parity-check (LDPC) codes. In the proposed algorithm, reduction in computational complexity is achieved by utilizing fast Fourier transform (FFT) with time shift in the check node process. The improvement in the decoding performance is achieved by utilizing an optimized integer constant in the variable node process. Simulation results show that the proposed algorithm achieves an overall coding gain improvement ranging from 0.04 to 0.46 dB. Moreover, when compared with the sum-product algorithm (SPA), the proposed decoding algorithm can achieve a reduction of 42%-67% of the total number of arithmetic operations required for the decoding process.

关键词： Computational complexity Coding gain Fast Fourier transform (FFT) Low-density parity-check (LDPC) codes Sum-product algorithm (SPA)

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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

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Control efficiency optimization and Sobol’s sensitivity indices of MTMDs design parameters for buffeting and flutter vibrations in a cable stayed bridge

Nazim Abdul NARIMAN

《结构与土木工程前沿（英文）》 2017年第11卷第1期页码 66-89 doi: 10.1007/s11709-016-0356-8

摘要： This paper studies optimization of three design parameters (mass ratio, frequency ratio and damping ratio) of multiple tuned mass dampers MTMDs that are applied in a cable stayed bridge excited by a strong wind using minimax optimization technique. ABAQUS finite element program is utilized to run numerical simulations with the support of MATLAB codes and Fast Fourier Transform FFT technique. The optimum values of these three parameters are validated with two benchmarks from the literature, first with Wang and coauthors and then with Lin and coauthors. The validation procedure detected a good agreement between the results. Box-Behnken experimental method is dedicated to formulate the surrogate models to represent the control efficiency of the vertical and torsional vibrations. Sobol’s sensitivity indices are calculated for the design parameters in addition to their interaction orders. The optimization results revealed better performance of the MTMDs in controlling the vertical and the torsional vibrations for higher mode shapes. Furthermore, the calculated rational effects of each design parameter facilitate to increase the control efficiency of the MTMDs in conjunction with the support of the surrogate models.

关键词： MTMDs power spectral density fast Fourier transform minimax optimization technique Sobol’s sensitivity indices Box-Behnken method

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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

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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

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A filtering-based bridge weigh-in-motion system on a continuous multi-girder bridge considering the influence lines of different lanes

Hanli WU, Hua ZHAO, Jenny LIU, Zhentao HU

《结构与土木工程前沿（英文）》 2020年第14卷第5期页码 1232-1246 doi: 10.1007/s11709-020-0653-0

摘要： A real-time vehicle monitoring is crucial for effective bridge maintenance and traffic management because overloaded vehicles can cause damage to bridges, and in some extreme cases, it will directly lead to a bridge failure. Bridge weigh-in-motion (BWIM) system as a high performance and cost-effective technology has been extensively used to monitor vehicle speed and weight on highways. However, the dynamic effect and data noise may have an adverse impact on the bridge responses during and immediately following the vehicles pass the bridge. The fast Fourier transform (FFT) method, which can significantly purify the collected structural responses (dynamic strains) received from sensors or transducers, was used in axle counting, detection, and axle weighing technology in this study. To further improve the accuracy of the BWIM system, the field-calibrated influence lines (ILs) of a continuous multi-girder bridge were regarded as a reference to identify the vehicle weight based on the modified Moses algorithm and the least squares method. experimental results indicated that the signals treated with FFT filter were far better than the original ones, the efficiency and the accuracy of axle detection were significantly improved by introducing the FFT method to the BWIM system. Moreover, the lateral load distribution effect on bridges should be considered by using the calculated average ILs of the specific lane individually for vehicle weight calculation of this lane.

关键词： bridge weigh-in-motion continuous bridge fast Fourier transform influence line axle weight calculation

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中国首个地基高分辨率傅里叶变换光谱观测站的大气成分长期观测研究 Article

刘诚, 孙友文, 单唱功, 王薇, Justus Notholt, Mathias Palm, 殷昊, 田园, 高吉熹, 毛慧琴

《工程（英文）》 2023年第22卷第3期页码 201-214 doi: 10.1016/j.eng.2021.11.022

摘要：

长期观测主要大气成分的体积混合比（VMR）廓线和柱总量对掌握中国气候变化和碳收支具有重要意义。本文对我国首个全球碳总柱观测网（TCCON）高分辨率傅里叶变换光谱仪（FTS）地基观测站，即合肥观测站开展了系统性研究。该观测站可观测30多种大气成分的柱总量和VMR廓线。本文公布了2014年以来合肥观测站观测到的部分关键大气成分的时间序列，总结了迄今为止该站点取得的主要研究成果，包括光谱反演表征和归一化、关键大气成分的总体演变特征、排放估计、卫星和化学传输模式（CTM）校验以及对大气污染来源和传输的相关研究。同时，本文还对合肥观测站的观测、科学研究和未来研究计划进行了展望。中国明确提出2030年二氧化碳排放达到峰值，2060年实现碳中和。合肥观测站将为中国政府制定绿色经济政策、实现碳中和及《巴黎协定》目标提供科学支撑。

关键词：遥感傅里叶变换大气污染温室气体气候变化

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Dynamics of structural systems with various frequency-dependent damping models

Li LI,Yujin HU,Weiming DENG,Lei LÜ,Zhe DING

《机械工程前沿（英文）》 2015年第10卷第1期页码 48-63 doi: 10.1007/s11465-015-0330-5

摘要：

The aim of this paper is to present the dynamic analyses of the system involving various damping models. The assumed frequency-dependent damping forces depend on the past history of motion via convolution integrals over some damping kernel functions. By choosing suitable damping kernel functions of frequency-dependent damping model, it may be derived from the familiar viscoelastic materials. A brief review of literature on the choice of available damping models is presented. Both the mode superposition method and Fourier transform method are developed for calculating the dynamic response of the structural systems with various damping models. It is shown that in the case of non-deficient systems with various damping models, the modal analysis with repeated eigenvalues are very similar to the traditional modal analysis used in undamped or viscously damped systems. Also, based on the pseudo-force approach, we transform the original equations of motion with nonzero initial conditions into an equivalent one with zero initial conditions and therefore present a Fourier transform method for the dynamics of structural systems with various damping models. Finally, some case studies are used to show the application and effectiveness of the derived formulas.

关键词： damping viscoelasticity dynamic analysis mode superposition method Fourier transform method

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Pyrolysis behaviors of oil sludge based on TG/FTIR and PY-GC/MS

Wei SONG, Jianguo LIU, Yongfeng NIE,

《环境科学与工程前沿（英文）》 2010年第4卷第1期页码 59-64 doi: 10.1007/s11783-009-0152-y

摘要： Pyrolysis is an alternative technology for oil sludge treatment. Thermogravimetric Analysis-Fourier Transform Infrared Spectroscopy and Pyrolysis-Gas Chromatography/Mass Spectrometry were employed to investigate the pyrolysis process and products of oil sludge. The pyrolysis process was divided into five stages: drying and gas desorption, oil volatilization, main pyrolysis, semi-coke charring, and mineral decomposition. The main reaction temperatures ranged from 497.6 K to 753.2 K. The products were mainly composed of pairs of alkane and alkene (carbon number ranges from 1 to 27). The mechanisms consisted of random chain scission followed by end chain scission at high temperatures with volatilization occurring during the whole process. This study is useful not only for the proper design of a pyrolysis system, but also for improving the utilization of liquid oil products.

关键词： oil sludge pyrolysis Thermogravimetric Analysis-Fourier Transform Infrared Spectroscopy (TG-FTIR) Pyrolysis-Gas Chromatography/Mass Spectrometry (PY-GC/MS)

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A combined experimental and theoretical study of micronized coal reburning

Hai ZHANG, Jiaxun LIU, Jun SHEN, Xiumin JIANG

《能源前沿（英文）》 2013年第7卷第1期页码 119-126 doi: 10.1007/s11708-012-0226-6

摘要： Micronized coal reburning (MCR) can not only reduce carbon in fly ash but also reduce NO emissions as compared to the conventional coal reburning. However, it has two major kinetic barriers in minimizing NO emission. The first is the conversion of NO into hydrogen cyanide (HCN) by conjunction with various hydrocarbon fragments. The second is the oxidation of HCN by association with oxygen-containing groups. To elucidate the advantages of MCR, a combination of Diffuse Reflection Fourier Transform Infrared (FTIR) experimental studies with Density Functional Theory (DFT) theoretical calculations is conducted in terms of the second kinetic barrier. FTIR studies based on Chinese Tiefa coal show that there are five hydroxide groups such as OH-π, OH-N, OH-OR , self-associated OH and free OH. The hydroxide groups increase as the mean particle size decreases expect for free OH. DFT calculations at the B3LYP/6-31 G(d) level indicate that HCN can be oxidized by hydroxide groups in three paths, HCN+OH→HOCN+H (path 1), HCN+OH→HNCO+H (path 2), and HCN+OH→CN+H O (path 3). The rate limiting steps for path 1, path 2 and path 3 are IM2→P1+H (170.66 kJ/mol activated energy), IM1→IM3 (231.04 kJ/mol activated energy), and R1+OH→P3+H O (97.14 kJ/mol activated energy), respectively. The present study of MCR will provide insight into its lower NO emission and guidance for further studies.

关键词： hydroxyl radicals Fourier transform infrared spectroscopy (FTIR) density functional theory (DFT) homogeneous reaction mechanism NO_x

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使用傅里叶变换红外成像进行高通量筛选 Article

Erdem Sasmaz, Kathleen Mingle, Jochen Lauterbach

《工程（英文）》 2015年第1卷第2期页码 234-242 doi: 10.15302/J-ENG-2015040

摘要：

组合库的有效平行筛选是高通量(HT) 多相催化工作流中最具挑战性的难题之一。目前，已有包括各种光学、质谱分析以及气相色谱技术在内的大量方法用于高通量催化剂研究。在这些技术中，快速扫描傅里叶变换红外(FTIR) 成像是最快、最通用的筛选技术。本文介绍了16 通道高通量反应器的新设计，并给出了其准确性和重复性试验结果。该系统的性能，通过在不同的还原剂–还原剂摩尔比、表面活性剂类型、金属和表面活性剂浓度、合成温度和升温速率下合成的商用Pd/Al₂O₃和氧化钴纳米粒子的一氧化碳氧化反应进行评估。

关键词：高通量傅里叶变换红外成像筛选氧化钴一氧化碳氧化

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Understanding the behavior of recycled aggregate concrete by using thermogravimetric analysis

Subhasis PRADHAN, Shailendra KUMAR, Sudhirkumar V. BARAI

《结构与土木工程前沿（英文）》 2020年第14卷第6期页码 1561-1572 doi: 10.1007/s11709-020-0640-5

摘要： The physio-chemical changes in concrete mixes due to different coarse aggregate (natural coarse aggregate and recycled coarse aggregate (RCA)) and mix design methods (conventional method and Particle Packing Method (PPM)) are studied using thermogravimetric analysis of the hydrated cement paste. A method is proposed to estimate the degree of hydration ( ) from chemically bound water ( ). The PPM mix designed concrete mixes exhibit lower . Recycled aggregate concrete (RAC) mixes exhibit higher and after 7 d of curing, contrary to that after 28 and 90 d. The chemically bound water at infinite time ( ) of RAC mixes are lower than the respective conventional concrete mixes. The lower , Ca(OH) bound water, free Ca(OH) content and FT-IR analysis substantiate the use of pozzolanic cement in the parent concrete of RCA. The compressive strength of concrete and cannot be correlated for concrete mixes with different aggregate type and mix design method as the present study confirms that the degree of hydration is not the only parameter which governs the macro-mechanical properties of concrete. In this regard, further study on the influence of interfacial transition zone, voids content and aggregate quality on macro-mechanical properties of concrete is needed.

关键词： recycled aggregate concrete Particle Packing Method thermogravimetric analysis chemically bound water degree of hydration Fourier transform infrared spectroscopy

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标题作者时间类型操作

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

null

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

一种通过循环前缀再利用改善OFDM系统带宽的新型节能ICI消除技术

Sandeep SAROWA, Harmanjeet SINGH, Sunil AGRAWAL, B. S. SOHI

期刊论文

An improved low-complexity sum-product decoding algorithm for low-density parity-check codes

Michaelraj Kingston ROBERTS,Ramesh JAYABALAN

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

Control efficiency optimization and Sobol’s sensitivity indices of MTMDs design parameters for buffeting and flutter vibrations in a cable stayed bridge

Nazim Abdul NARIMAN

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

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

A filtering-based bridge weigh-in-motion system on a continuous multi-girder bridge considering the influence lines of different lanes

Hanli WU, Hua ZHAO, Jenny LIU, Zhentao HU

期刊论文

中国首个地基高分辨率傅里叶变换光谱观测站的大气成分长期观测研究