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利用子空间的投影和跟踪改进OFDM信道估计

董亮,曹秀英,毕光国

《中国工程科学》 2006年 第8卷 第11期   页码 86-93

摘要:

OFDM系统的LS信道估计可看作真实信道频率响应的一个有噪观察值,因此可采用子空间投影方法对噪声进行压缩。分析了利用子空间投影方法改进LSOFDM信道估计性能的实质,给出了利用子空间投影改进OFDM信道估计的一般框架,在此基础上将子空间投影推广到非LS信道估计方法。当信号子空间随时间变化时,需要采用子空间跟踪技术保持对信号子空间的良好估计,因此提出了一种基于子空间跟踪的参数化信道估计方法,仿真表明这种方法在性能上优于非参数化时的相应方法。

关键词: OFDM     子空间     投影     跟踪     信道估计    

一种工业过程时变参数估计新算法——修正目标函数法

张承慧

《中国工程科学》 2001年 第3卷 第11期   页码 54-59

摘要:

针对某些工业过程控制参数高度时变的特点和LS拟合算法存在病态估计的现象,提出了一类基于 修正目标函数的时变参数估计算法,并给出递推辅助变量算法。此类算法不仅具有较强的实时跟踪能力和较高 的估计精度,而且能克服病态估计,摆脱了伪随机信号在工程中带来的麻烦。新算法没有增加计算量,非常适 合于工程应用,仿真及实际应用结果都证明新算法是有效的。文中给出了有关新算法的定理及其证明。

关键词: 参数估计     计算方法     LS算法     时变系统     工业生产    

Intelligent algorithm for optimal meter placement and bus voltage estimation in ring main distribution

L. RAMESH, N. CHAKRABORTY, S. P. CHOWDHURY

《能源前沿(英文)》 2012年 第6卷 第1期   页码 47-56 doi: 10.1007/s11708-011-0159-5

摘要: The advancement in power distribution system poses a great challenge to power engineering researchers on how to best monitor and estimate the state of the distribution network. This paper is executed in two stage processes. The first stage is to identify the optimal location for installation of monitoring instrument with minimal investment cost. The second stage is to estimate the bus voltage magnitude, where real time measurement is conducted and measured through identified meter location which is more essential for decision making in distribution supervisory control and data acquisition system (DSCADA). The hybrid intelligent technique is applied to execute the above two algorithms. The algorithms are tested with institute of electrical and electronics engineers (IEEE) and Tamil Nadu electricity board (TNEB) benchmark systems. The simulated results proves that the swarm tuned artificial neural network (ANN) estimator is best suited for accurate estimation of voltage with different noise levels.

关键词: artificial intelligence     power distribution control     state estimation    

An operating state estimation model for integrated energy systems based on distributed solution

Dengji ZHOU, Shixi MA, Dawen HUANG, Huisheng ZHANG, Shilie WENG

《能源前沿(英文)》 2020年 第14卷 第4期   页码 801-816 doi: 10.1007/s11708-020-0687-y

摘要: In view of the disadvantages of the traditional energy supply systems, such as separate planning, separate design, independent operating mode, and the increasingly prominent nonlinear coupling between various sub-systems, the production, transmission, storage and consumption of multiple energy sources are coordinated and optimized by the integrated energy system, which improves energy and infrastructure utilization, promotes renewable energy consumption, and ensures reliability of energy supply. In this paper, the mathematical model of the electricity-gas interconnected integrated energy system and its state estimation method are studied. First, considering the nonlinearity between measurement equations and state variables, a performance simulation model is proposed. Then, the state consistency equations and constraints of the coupling nodes for multiple energy sub-systems are established, and constraints are relaxed into the objective function to decouple the integrated energy system. Finally, a distributed state estimation framework is formed by combining the synchronous alternating direction multiplier method to achieve an efficient estimation of the state of the integrated energy system. A simulation model of an electricity-gas interconnected integrated energy system verifies the efficiency and accuracy of the state estimation method proposed in this paper. The results show that the average relative errors of voltage amplitude and node pressure estimated by the proposed distributed state estimation method are only 0.0132% and 0.0864%, much lower than the estimation error by using the Lagrangian relaxation method. Besides, compared with the centralized estimation method, the proposed distributed method saves 5.42 s of computation time. The proposed method is more accurate and efficient in energy allocation and utilization.

关键词: integrated energy system     state estimation     electricity-gas coupling energy system     nonlinear coupling     distributed solution    

Bayes estimation of residual life by fusing multisource information

Qian ZHAO, Xiang JIA, Zhi-jun CHENG, Bo GUO

《工程管理前沿(英文)》 2018年 第5卷 第4期   页码 524-532 doi: 10.15302/J-FEM-2018034

摘要:

Residual life estimation is essential for reliability engineering. Traditional methods may experience difficulties in estimating the residual life of products with high reliability, long life, and small sample. The Bayes model provides a feasible solution and can be a useful tool for fusing multisource information. In this study, a Bayes model is proposed to estimate the residual life of products by fusing expert knowledge, degradation data, and lifetime data. The linear Wiener process is used to model degradation data, whereas lifetime data are described via the inverse Gaussian distribution. Therefore, the joint maximum likelihood (ML) function can be obtained by combining lifetime and degradation data. Expert knowledge is used according to the maximum entropy method to determine the prior distributions of parameters, thereby making this work different from existing studies that use non-informative prior. The discussion and analysis of different types of expert knowledge also distinguish our research from others. Expert knowledge can be classified into three categories according to practical engineering. Methods for determining prior distribution by using the aforementioned three types of data are presented. The Markov chain Monte Carlo is applied to obtain samples of the parameters and to estimate the residual life of products due to the complexity of the joint ML function and the posterior distribution of parameters. Finally, a numerical example is presented. The effectiveness and practicability of the proposed method are validated by comparing it with residual life estimation that uses non-informative prior. Then, its accuracy and correctness are proven via simulation experiments.

关键词: residual life estimation     Bayes model     linear Wiener process    

Thermal degradation kinetics and lifetime estimation for polycarbonate/polymethylphenylsilsesquioxane

Jiangbo WANG, Zhong XIN

《化学科学与工程前沿(英文)》 2009年 第3卷 第2期   页码 167-171 doi: 10.1007/s11705-009-0006-y

摘要: The thermal degradation behaviors of polycarbonate/polymethylphenylsilsesquioxane (FRPC) composites were investigated by thermogravimetric analysis (TGA) under isothermal conditions in nitrogen atmosphere. The isothermal kinetics equation was used to describe the thermal degradation process. The results showed that activation energy ( ), in the case of isothermal degradation, was a quick increasing function of conversion (α) for polycarbonate (PC) but was a strong and decreasing function of conversion for FRPC. Under the isothermal condition, the addition of polymethylphenylsilsesquioxane (PMPSQ) retardanted the thermal degradation and enhanced the thermal stability of PC during the early and middle stages of thermal degradation. It also indicated a possible existence of a difference in nucleation, nuclei growth, and gas diffusion mechanism in the thermal degradation process between PC and FRPC. Meanwhile, the addition of PMPSQ influenced the lifetime of PC, but the composite still met the demand in manufacturing and application.

关键词: polycarbonate     polymethylphenylsilsesquioxane     thermal degradation kinetics     activation energy     lifetime    

Hierarchical parameter estimation of DFIG and drive train system in a wind turbine generator

Xueping PAN, Ping JU, Feng WU, Yuqing JIN

《机械工程前沿(英文)》 2017年 第12卷 第3期   页码 367-376 doi: 10.1007/s11465-017-0429-y

摘要:

A new hierarchical parameter estimation method for doubly fed induction generator (DFIG) and drive train system in a wind turbine generator (WTG) is proposed in this paper. Firstly, the parameters of the DFIG and the drive train are estimated locally under different types of disturbances. Secondly, a coordination estimation method is further applied to identify the parameters of the DFIG and the drive train simultaneously with the purpose of attaining the global optimal estimation results. The main benefit of the proposed scheme is the improved estimation accuracy. Estimation results confirm the applicability of the proposed estimation technique.

关键词: wind turbine generator     DFIG     drive train system     hierarchical parameter estimation method     trajectory sensitivity technique    

Penetrance estimation of variants in paroxysmal kinesigenic dyskinesia and infantile convulsions

《医学前沿(英文)》 2021年 第15卷 第6期   页码 877-886 doi: 10.1007/s11684-021-0863-4

摘要: Proline-rich transmembrane protein 2 (PRRT2) is the leading cause of paroxysmal kinesigenic dyskinesia (PKD), benign familial infantile epilepsy (BFIE), and infantile convulsions with choreoathetosis (ICCA). Reduced penetrance of PRRT2 has been observed in previous studies, whereas the exact penetrance has not been evaluated well. The objective of this study was to estimate the penetrance of PRRT2 and determine its influencing factors. We screened 222 PKD index patients and their available relatives, identified 39 families with pathogenic or likely pathogenic (P/LP) PRRT2 variants via Sanger sequencing, and obtained 184 PKD/BFIE/ICCA families with P/LP PRRT2 variants from the literature. Penetrance was estimated as the proportion of affected variant carriers. PRRT2 penetrance estimate was 77.6% (95% confidence interval (CI) 74.5%–80.7%) in relatives and 74.5% (95% CI 70.2%–78.8%) in obligate carriers. In addition, we first observed that penetrance was higher in truncated than in non-truncated variants (75.8% versus 50.0%, P = 0.01), higher in Asian than in Caucasian carriers (81.5% versus 68.5%, P = 0.004), and exhibited no difference in gender or parental transmission. Our results are meaningful for genetic counseling, implying that approximately three-quarters of PRRT2 variant carriers will develop PRRT2-related disorders, with patients from Asia or carrying truncated variants at a higher risk.

关键词: penetrance     PRRT2     paroxysmal kinesigenic dyskinesia     infantile convulsions    

Smart model for accurate estimation of solar radiation

Lazhar ACHOUR, Malek BOUHARKAT, Ouarda ASSAS, Omar BEHAR

《能源前沿(英文)》 2020年 第14卷 第2期   页码 383-399 doi: 10.1007/s11708-017-0505-3

摘要: Prediction of solar radiation has drawn increasing attention in the recent years. This is because of the lack of solar radiation measurement stations. In the present work, 14 solar radiation models have been used to assess monthly global solar radiation on a horizontal surface as function of three parameters: extraterrestrial solar irradiance ( ), duration sunshine ( ) and daylight hours ( ). Since it has been observed that each model is adequate for some months of the year, one model cannot be used for the prediction of the whole year. Therefore, a smart hybrid system is proposed which selects, based on the intelligent rules, the most suitable prediction model of the 14 models listed in this study. For the test and evaluation of the proposed models, Tamanrasset city, which is located in the south of Algeria, is selected for this study. The meteorological data sets of five years (2000–2004) have been collected from the Algerian National Office of Meteorology (NOM), and two spatial databases. The results indicate that the new hybrid model is capable of predicting the monthly global solar radiation, which offers an excellent measuring accuracy of values ranging from 93% to 97% in this location.

关键词: global solar radiation     statistical indicator     hybrid model     spatial database     correlation coefficients    

A frequency error estimation for isogeometric analysis of Kirchhoff–Love cylindrical shells

《结构与土木工程前沿(英文)》 doi: 10.1007/s11709-023-0006-x

摘要: A frequency error estimation is presented for the isogeometric free vibration analysis of Kirchhoff–Love cylindrical shells using both quadratic and cubic basis functions. By analyzing the discrete isogeometric equations with the aid of harmonic wave assumption, the frequency error measures are rationally derived for the quadratic and cubic formulations for Kirchhoff–Love cylindrical shells. In particular, the governing relationship of the continuum frequency for Kirchhoff–Love cylindrical shells is naturally embedded into the frequency error measures without the need of explicit frequency expressions, which usually are not trivial for the shell problems. In accordance with these theoretical findings, the 2nd and 4th orders of frequency accuracy are attained for the isogeometric schemes using quadratic and cubic basis functions, respectively. Numerical results not only thoroughly verify the theoretical convergence rates of frequency solutions, but also manifest an excellent magnitude match between numerical and theoretical frequency errors for the isogeometric free vibration analysis of Kirchhoff–Love cylindrical shells.

关键词: isogeometric analysis     Kirchhoff–Love cylindrical shell     free vibration     frequency error     convergence    

Joint DOA and channel estimation with data detection based on 2D unitary ESPRIT in massive MIMO systems Article

Jing-ming KUANG, Yuan ZHOU, Ze-song FEI

《信息与电子工程前沿(英文)》 2017年 第18卷 第6期   页码 841-849 doi: 10.1631/FITEE.1700025

摘要: 针对大规模均匀矩形阵列提出了一种新型二维波达角和信道联合估计技术以及信号检测技术。传统波达角估计技术都建立在信道冲击响应已知的前提下,然而,在大规模天线系统中,信道估计非常具有挑战性。首先利用训练序列估计出用户与天线之间的联合信道冲击响应,然后利用该估计值基于酉ESPRIT算法获得二维角度估计,接下来可以获得不同路径的定向信道冲击响应估计。所提估计算法可以获得闭式解,避免了搜索和配对过程。与此同时,提出了一种简化的信号检测过程,该过程可以降低矩阵求逆的维度,从而降低检测复杂度。对多种情况进行了仿真验证,仿真结果证明了所提算法的有效性。

关键词: 二维波达角估计;信道冲击响应估计;信号检测;均匀矩形阵列;大规模天线    

Construction Activity Analysis of Workers Based on Human Posture Estimation Information

Xuhong Zhou,Shuai Li,Jiepeng Liu,Zhou Wu,Yohchia Frank Chen,

《工程(英文)》 doi: 10.1016/j.eng.2023.10.004

摘要: Identifying workers’ construction activities or behaviors can enable managers to better monitor labor efficiency and construction progress. However, current activity analysis methods for construction workers rely solely on manual observations and recordings, which consumes considerable time and has high labor costs. Researchers have focused on monitoring on-site construction activities of workers. However, when multiple workers are working together, current research cannot accurately and automatically identify the construction activity. This research proposes a deep learning framework for the automated analysis of the construction activities of multiple workers. In this framework, multiple deep neural network models are designed and used to complete worker key point extraction, worker tracking, and worker construction activity analysis. The designed framework was tested at an actual construction site, and activity recognition for multiple workers was performed, indicating the feasibility of the framework for the automated monitoring of work efficiency.

关键词: Pose estimation     Activity analysis     Object tracking     Construction workers     Automatic systems    

A novel period estimation method for X-ray pulsars based on frequency subdivision

Li-rong SHEN,Xiao-ping LI,Hai-feng SUN,Hai-yan FANG,Meng-fan XUE

《信息与电子工程前沿(英文)》 2015年 第16卷 第10期   页码 858-870 doi: 10.1631/FITEE.1500052

摘要: Period estimation of X-ray pulsars plays an important role in X-ray pulsar based navigation (XPNAV). The fast Lomb periodogram is suitable for period estimation of X-ray pulsars, but its performance in terms of frequency resolution is limited by data length and observation time. Longer observation time or oversampling can be employed to improve frequency analysis results, but with greatly increased computational complexity and large amounts of sampling data. This greatly restricts real-time autonomous navigation based on X-ray pulsars. To resolve this issue, a new method based on frequency subdivision and the continuous Lomb periodogram (CLP) is proposed to improve precision of period estimation using short-time observation data. In the proposed method, an initial frequency is first calculated using fast Lomb periodogram. Then frequency subdivision is performed near the initial frequency to obtain frequencies with higher precision. Finally, a refined period is achieved by calculating the CLP in the obtained frequencies. Real data experiments show that when observation time is shorter than 135 s, the proposed method improves period estimation precision by 1–3 orders of magnitude compared with the fast Lomb periodogram and fast Fourier transform (FFT) methods, with only a slight increase in computational complexity. Furthermore, the proposed method performs better than efsearch (a period estimation method of HEAsoft) with lower computational complexity. The proposed method is suitable for estimating periods of X-ray pulsars and obtaining the rotation period of variable stars and other celestial bodies.

关键词: Pulsar navigation     Period estimation     Frequency subdivision     Continuous Lomb periodogram    

Capacity estimation and preliminary strategy for reducing the release of dioxins in China

YU Gang, ZHANG Qing, HUANG Jun, CAI Zhenxiao, SUI Qian

《环境科学与工程前沿(英文)》 2007年 第1卷 第1期   页码 13-17 doi: 10.1007/s11783-007-0002-8

摘要: As a party of the Stockholm Convention on Persistent Organic Pollutants, China must submit its national implementation plan (NIP) for this convention. The strategy and action plan for reducing the release of dioxins in China are the most important components of the NIP. Three problems are key points for developing such strategy and action plan what are the key sources for applying the best available technology/best environmental practice (BAT/BEP) to reduce the release of dioxins? How about the capacity for reducing the dioxins release from the key sources? Where are the areas of priority for applying BAT/BEP? This paper shows the efforts towards the solution of these problems. The list of key sources covering about half of the total dioxins release was determined considering four criteria. The capacity of key sources were estimated based on the difference between the emission factor corresponding to the actual situation in 2004 and that corresponding to the scenario that all key sources have been applied BAT/BEP to reduce the dioxins release. The priority analysis using the geographical information system (GIS) tool has revealed that eastern provinces should be of high priority in the future reduction activities of dioxins release in China.

关键词: GIS     difference     capacity     scenario     implementation    

Profiling and annotation combined method formultimedia application specificMPSoCperformance estimation

Kai HUANG,Xiao-xu ZHANG,Si-wen XIU,Dan-dan ZHENG,Min YU,De MA,Kai HUANG,Gang CHEN,Xiao-lang YAN

《信息与电子工程前沿(英文)》 2015年 第16卷 第2期   页码 135-151 doi: 10.1631/FITEE.1400239

摘要: Accurate and fast performance estimation is necessary to drive design space exploration and thus support important design decisions. Current techniques are either time consuming or not accurate enough. In this paper, we solve these problems by presenting a hybrid method for multimedia multiprocessor system-on-chip (MPSoC) performance estimation. A general coverage analysis tool GNU gcov is employed to profile the execution statistics during the native simulation. To tackle the complexity and keep the analysis and simulation manageable, the orthogonalization of communication and computation parts is adopted. The estimation result of the computation part is annotated to a transaction accurate model for further analysis, by which a gradual refinement of MPSoC performance estimation is supported. The implementation and its experimental results prove the feasibility and efficiency of the proposed method.

关键词: MPSoC     Gradual refinement     Native simulation     Performance estimation     Profiling     Annotation     Gcov    

标题 作者 时间 类型 操作

利用子空间的投影和跟踪改进OFDM信道估计

董亮,曹秀英,毕光国

期刊论文

一种工业过程时变参数估计新算法——修正目标函数法

张承慧

期刊论文

Intelligent algorithm for optimal meter placement and bus voltage estimation in ring main distribution

L. RAMESH, N. CHAKRABORTY, S. P. CHOWDHURY

期刊论文

An operating state estimation model for integrated energy systems based on distributed solution

Dengji ZHOU, Shixi MA, Dawen HUANG, Huisheng ZHANG, Shilie WENG

期刊论文

Bayes estimation of residual life by fusing multisource information

Qian ZHAO, Xiang JIA, Zhi-jun CHENG, Bo GUO

期刊论文

Thermal degradation kinetics and lifetime estimation for polycarbonate/polymethylphenylsilsesquioxane

Jiangbo WANG, Zhong XIN

期刊论文

Hierarchical parameter estimation of DFIG and drive train system in a wind turbine generator

Xueping PAN, Ping JU, Feng WU, Yuqing JIN

期刊论文

Penetrance estimation of variants in paroxysmal kinesigenic dyskinesia and infantile convulsions

期刊论文

Smart model for accurate estimation of solar radiation

Lazhar ACHOUR, Malek BOUHARKAT, Ouarda ASSAS, Omar BEHAR

期刊论文

A frequency error estimation for isogeometric analysis of Kirchhoff–Love cylindrical shells

期刊论文

Joint DOA and channel estimation with data detection based on 2D unitary ESPRIT in massive MIMO systems

Jing-ming KUANG, Yuan ZHOU, Ze-song FEI

期刊论文

Construction Activity Analysis of Workers Based on Human Posture Estimation Information

Xuhong Zhou,Shuai Li,Jiepeng Liu,Zhou Wu,Yohchia Frank Chen,

期刊论文

A novel period estimation method for X-ray pulsars based on frequency subdivision

Li-rong SHEN,Xiao-ping LI,Hai-feng SUN,Hai-yan FANG,Meng-fan XUE

期刊论文

Capacity estimation and preliminary strategy for reducing the release of dioxins in China

YU Gang, ZHANG Qing, HUANG Jun, CAI Zhenxiao, SUI Qian

期刊论文

Profiling and annotation combined method formultimedia application specificMPSoCperformance estimation

Kai HUANG,Xiao-xu ZHANG,Si-wen XIU,Dan-dan ZHENG,Min YU,De MA,Kai HUANG,Gang CHEN,Xiao-lang YAN

期刊论文