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Direction finding for two-dimensional incoherently distributed sources with Hadamard shift invariance in non-uniform orthogonal arrays

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Chinese Journal of Aeronautics 2018年第12期31卷 2260-2269页

作者： Zhengliang DAI Weijia CUI Daming WANG bin ba Chao WANG Yankui ZHANG National Digital Switching System Engineering&Technological Research Center Zhengzhou 450001China

This paper proposes a novel algorithm for Two-Dimensional(2D) central Directionof-Arrival(DOA) estimation of incoherently distributed sources. In particular, an orthogonal array structure consisting of two Non-uniform Linear Arrays(NLAs) is considered. based on first-order Taylor series approximation, the Generalized Array Manifold(GAM) model can first be established to separate the central DOAs from the original array manifold. Then, the Hadamard rotational invariance relationships inside the GAMs of two NLAs are identified. With the aid of such relationships, the central elevation and azimuth DOAs can be estimated through a search-free polynomial rooting method. Additionally, a simple parameter pairing of the estimated 2D angular parameters is also accomplished via the Hadamard rotational invariance relationship inside the GAM of the whole array. A secondary but important result is a derivation of closed-form expressions of the Cramer-Rao lower bound. The simulation results show that the proposed algorithm can achieve a remarkably higher precision at less complexity increment compared with the existing low-complexity methods, which benefits from the larger array aperture of the NLAs. Moreover, it requires no priori information about the angular distributed function.

关键词： Array signal processing Cramer-Rao lower bound Direction-of-Arrival(DOA) estimation Hadamard rotational invariance Incoherently distributed sources Non-uniform orthogonal array

An alternative approach to match field production data from unconventional gas-bearing systems

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Petroleum Science 2020年第5期17卷 1370-1388页

作者： Zhi-Gang Zhang Yan-bao Liu Hai-Tao Sun Wei Xiong Kai Shen Quan-bin ba National Key Laboratory of Gas Disaster Detecting Preventing and Emergency ControllingChongqing 400037China Chongqing Research Institute of China Coal Technology and Engineering Group Crop. Chongqing 400037China School of Resources and Safety Engineering Chongqing UniversityChongqing 400045China

Nowadays,the unconventional gas-bearing system plays an increasingly important role in energy *** performances of the current history-matching techniques are not satisfied when applied to such *** overcome this shortfall,an alternative approach was developed and applied to investigate production data from an unconventional gas-bearing *** this approach,the fluid flow curve obtained from the field is the superposition of a series of Gaussian *** automatic computing program was developed in the MATLAB,and both gas and water field data collected from a vertical well in the Linxing Block,Ordos basin,were used to present the data processing *** the reservoir study,the automatic computing program was applied to match the production data from a single coal seam,multiple coal seams and multiple vertically stacked reservoirs with favourable fitting *** with previous approaches,the proposed approach yields better results for both gas and water production data and can calculate the contributions from different *** start time of the extraction for each gas-containing unit can also be *** new approach can be applied to the field data prediction and designation for the well locations and patterns at the reservoir scale.

关键词： Gaussian function Flow rate Unconventional gas Ordos basin Gas-bearing reservoirs

Cytochrome P450 2E1 RsaI/PstI and DraI Polymorphisms Are Risk Factors for Lung Cancer in Mongolian and Han Population in Inner Mongolia

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Chinese Journal of Cancer Research 2011年第2期23卷 107-111页

作者： Xiu-lan Su ba bin Hong-wei Cui Mei-rong Ran Clinical Medical Center Affiliated Hospital Inner Mongolian Medical College Hohhot 010050 China Department of Internal Medicine Medical Emergency Center of Kangbashi New Direct Erdos City Inner Mongolia China

Objective： To explore the relationship between cytochrome P450 2E1 （CYP2E1） RsaI/PstI and DraI polymorphism and lung cancer susceptibility in Mongolian and Han population in Inner Mongolia of China. Methods： CYP2E1 RsaI/PstI and DraI polymorphisms were detected by polymerase chain reaction-restriction fragment length polymorphism in 64 lung cancer patients, 150 healthy Mongolian and 150 healthy Han individuals. The distribution of genotype and allele frequencies of CYP2E1 RsaI/PstI and DraI polymorphisms were studied. Results： The risk of lung cancer was increased in individuals with CYP2E1 （cl/cl） and CYP2E1 （DD） with OR values of 2.431 （95%CI=1.082-5.460） and 2.778 （95%CI=1.358-5.683） respectively （P0.05）. When CYP2E1 RsaI/PstI and DraI polymorphisms were combined, the risk of lung cancer was reduced in individuals with CYP2E1 （cl/c2＋c2/c2 and DD＋CC） with OR values of 0.233 （95%CI=0.088-0.615, P0.05）. In smokers, the susceptibility to lung cancer was higher in the individuals with CYP2E1 （c1/c1） and CYP2E1 （DD） than in the individuals with c2 and C allele （P0.05, OR=2.643 and 4.308 respectively）. There was no significant difference in distribution of CYP2E1 genotype frequency between healthy Mongolian, Han population and lung cancer patients, healthy controls in Inner Mongolia. Conclusion： CYP2E1 （c1/c1） and CYP2E1 （DD） are predisposing factors of lung cancer in population in Inner Mongolia. CYP2E1 （c2﹢C） co-mutation may decrease the risk of lung cancer. Smoking exerts synergetic effect with CYP2E1 （c1/c1） and CYP2E1 （DD） on the occurrence of lung cancer.

关键词： Cytochrome p450 2E1 Gene polymorphism Lung cancer Susceptivity

SEPARATION OF SMALL SOLID PARTICLES baSED ON ULTRASONIC ROTATION

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SEPARATION OF SMALL SOLID PARTICLES BASED ON ULTRASONIC ROTA...

基于贝叶斯自动相关性确定的稀疏重构正交频分复用信号时延估计算法

2013全国压电和声波理论及器件技术研讨会

作者： Hui-bin ba Jun-hui HU Han-ming PENG State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics

In this work,we proposed and developed an ultrasonic actuator which can be used to separate mixed small solid particles in *** ultrasonic actuator consists of an ultrasonic sandwich-type transducer and an aluminum plate which is extended from an end plate of the *** aluminum plate is asymmetrically excited by the transducer,to vibrate *** transducer operates in the thickness mode and has a resonance frequency of 91.7 *** mixtures used in the experiments are obtained by the combination of any two particles among shrimp eggs,glass balls and refined *** experiments show that the glass balls can be separated from the mixture of glass balls and shrimp eggs,and salt particles separated from the mixture of salt particles and shrimp *** device used in the method has no mechanical rotary part and the separation can be quickly completed.

关键词： ultrasonic separation small particles rotation

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电子与信息学报 2019年第10期41卷 2318-2324页

作者：崔维嘉张鹏巴斌信息工程大学信息系统工程学院

针对复杂环境下,单测量矢量(SMV)条件下的正交频分复用(OFDM)时延估计问题,该文提出了一种基于贝叶斯自动相关性确定(baRD)的稀疏重构时延估计算法。该算法运用贝叶斯框架,从进一步挖掘有用信息的角度入手,引入不对称的自动相关性确定(A... 详细信息

针对复杂环境下,单测量矢量(SMV)条件下的正交频分复用(OFDM)时延估计问题,该文提出了一种基于贝叶斯自动相关性确定(baRD)的稀疏重构时延估计算法。该算法运用贝叶斯框架,从进一步挖掘有用信息的角度入手,引入不对称的自动相关性确定(ARD)先验,融入参数估计过程中,有效提升了低信噪比(SNR)和SMV条件下的时延估计精度。该算法首先基于OFDM信号物理层协议数据单元估计出的信道频域响应构造稀疏化实数域表示模型,然后对模型中的噪声和稀疏系数矢量进行概率假设,同时引入自动相关性确定先验;最后根据贝叶斯框架,通过期望最大化(EM)算法求解超参数,实现对时延的估计。仿真实验表明,该算法具有更好的估计性能,在信噪比较高时更加贴近克拉美罗界(CRB)。同时基于通用软件无线电外设(USRP),利用实际信号对所提算法进行了有效性地验证。

关键词：时延估计神经网络自动相关性确定(ARD) 通用软件无线电外设(USRP)

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基于细化频谱的频率迭代插值估计算法

电子与信息学报 2017年第9期39卷 2141-2147页

作者：崔维嘉鲁航巴斌解放军信息工程大学郑州450001

在加性高斯白噪声环境的单频复指数信号频率估计中,针对现有频率估计算法估计误差分布不均且估计精度较低的问题,该文提出一种细化频谱迭代插值估计算法。该算法首先根据半长信号的快速傅里叶变换峰值位置计算细化频谱,再利用细化频谱... 详细信息

在加性高斯白噪声环境的单频复指数信号频率估计中,针对现有频率估计算法估计误差分布不均且估计精度较低的问题,该文提出一种细化频谱迭代插值估计算法。该算法首先根据半长信号的快速傅里叶变换峰值位置计算细化频谱,再利用细化频谱幅值进行频率的无偏插值估计,最后利用估计结果和全长信号更新细化频谱并进行迭代插值重估。仿真结果表明,与现有算法相比,所提算法估计误差分布均匀,且在高信噪比的所有频率范围和低信噪比的大部分频率范围内估计精度更高。同时仿真表明,所提算法在加性均匀噪声环境中也有较好的估计性能。

关键词：频率估计细化频谱插值估计

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基于循环匹配追踪的稀疏重构时延估计算法

电子与信息学报 2019年第3期41卷 523-529页

作者：崔维嘉张鹏巴斌信息工程大学信息系统工程学院郑州450001

在单样本(SMV)、低信噪比条件下,稀疏重构方法可提升时延估计精度,但现有的重构算法在支撑集元素的选择中存在错选和漏选的情况,从而导致估计精度受限。针对上述问题,该文提出一种基于循环匹配追踪(LMP)的稀疏重构时延估计算法。该方法... 详细信息

在单样本(SMV)、低信噪比条件下,稀疏重构方法可提升时延估计精度,但现有的重构算法在支撑集元素的选择中存在错选和漏选的情况,从而导致估计精度受限。针对上述问题,该文提出一种基于循环匹配追踪(LMP)的稀疏重构时延估计算法。该方法引入了"循环删除,匹配添加"的思想,有效提升了直达径的估计精度。算法首先建立信道冲激响应稀疏表示模型;然后在获得初始支撑集的前提下,先循环删除支撑集内的元素,再从支撑集补集中依据与当前残差内积值最大来匹配添加新元素,直至残差内积基本不变;最后利用时延值与稀疏支撑集的关系得到了时延的估计值。仿真结果表明,所提算法相比于传统稀疏重构时延估计算法具有更高的估计精度。同时基于USRP平台,利用实际信号对所提算法进行了有效性验证。

关键词：时延估计稀疏重构循环匹配追踪支撑集 USRP平台

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基于回溯筛选的稀疏重构时延估计算法

物理学报 2016年第21期65卷 88-96页

作者：冷雪冬巴斌逯志宇王大鸣解放军信息工程大学信息系统工程学院郑州450001

针对无线定位中时延估计在小样本(单快拍)、低信噪比条件下需要大量独立分布测量数据问题,提出了一种基于回溯筛选的稀疏重构时延估计算法,实现了单快拍、低信噪比条件下接收信号的精确时延估计.该算法首先建立接收信号的稀疏表示模型,... 详细信息

针对无线定位中时延估计在小样本(单快拍)、低信噪比条件下需要大量独立分布测量数据问题,提出了一种基于回溯筛选的稀疏重构时延估计算法,实现了单快拍、低信噪比条件下接收信号的精确时延估计.该算法首先建立接收信号的稀疏表示模型,然后基于该模型建立正交观测矩阵,最后在重构算法中引入回溯筛选思想,利用时延与观测矩阵之间的一一对应关系得到时延的无偏估计.对该模型下时延估计的克拉美罗界进行了推导.仿真分析表明,所提方法在单快拍、低信噪比条件下精度远高于求根多重信号分类算法,相比于正交匹配追踪算法,在较小的复杂度代价下性能得到了较大提升.

关键词：稀疏重构时延估计回溯筛选测量矩阵正交化

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多观测值约束的可见光定位算法

西安电子科技大学学报 2017年第4期44卷 156-161页

作者：鲁航崔维嘉巴斌逯志宇信息工程大学信息系统工程学院河南郑州450001

在室内复杂多噪的可见光传输环境中,针对由于传统接收光强检测定位存在的建模不准确而导致定位精度低和成像定位存在的终端位置坐标与姿态角约束信息不足的问题,提出一种多观测值约束的可见光定位算法.该算法首先根据接收光强检测定位... 详细信息

在室内复杂多噪的可见光传输环境中,针对由于传统接收光强检测定位存在的建模不准确而导致定位精度低和成像定位存在的终端位置坐标与姿态角约束信息不足的问题,提出一种多观测值约束的可见光定位算法.该算法首先根据接收光强检测定位与成像定位建立联合定位状态空间模型;据此构造系统观测值与状态值,列出观测方程与状态方程;最后利用无损卡尔曼滤波算法进行求解得到定位结果.仿真实验表明,与接收光强检测定位和成像定位相比,该算法的定位结果均方误差更加逼近克拉美罗下界且可定位概率更高.

关键词：可见光室内定位系统成像传感器克拉美罗下界