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Application of the multi-cycle estimator of Doppler and TDOA to passively locating targets exploiting non-cooperative transmitters

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Progress in Natural Science:Materials International 2003年第10期 36-40页

作者： huang zhitao*, jiang wenli and zhou yiyu(School of Electronic Science and Engineering, National University of Defense Technology, Changsha 410073, China) School of Electronic Science and Engineering National University of Defense Technology Changsha 410073 China

By exploiting the cyclostationary property of non cooperative source signals, the problem of joint time difference of arrival (TDOA) and Doppler estimation is discussed, and the multi cycle estimator is developed by generalizing the single cycle estimator. Utilizing a special commercial FM radio as a non cooperative transmitter, some practical experiments are carried out. The right estimates of TDOA and Doppler of a particular airplane can really be obtained by processing the measurements with the multi cycle estimation algorithm. Through adding some slowly time variant white Gaussian noise to the original measurements, some independent Monte Carlo simulations are performed, and the simulation results reveal that the multi cycle estimator is really superior to the single cycle estimator and the conventional cross correlation method.

关键词： non cooperative transmitter cycle estimator joint TDOA and Doppler estimation.

Hydrocarbon Generation Characteristics of Source Rocks from Different Saline Environments in the Dongpu Depression,Bohai Bay Basin,China

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1260-1278页

作者： LI Wendu ZHANG Pengyuan jiang Fujie ZHANG Yunxian huang Renda XU Tianwu zhou Yongshui LI Longlong jiang wenli State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Beijing 100083China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China Basin and Reservoir Research Center China University of Petroleum(Beijing)Beijing 102249China Zhongyuan Oilfield Branch SINOPECPuyangHenan 457001China Wuxi Research Institute of Petroleum Geology Sinopec Petroleum Exploration&Production Research InstituteWuxiJiangsu 214000China Strategy Research Center of Oil and Gas Resources Ministry of Land and ResourcesBeijing 100034China

The Dongpu Depression is a secondary salt-bearing tectonic unit in the Bohai Bay Basin,eastern *** depositional environment of this depression regarding its Paleogene strata is clearly different in plane,including the saltwater environment(SE)in the north,the freshwater environment(FE)in the south and the brackish water environment(BE)in the *** result of oil and gas exploration in the Dongpu Depression shows that more than 90%of the proven oil reserves are distributed in the northern saltwater *** studies indicate that the organic geochemistry characteristics and the hydrocarbon generation capacity of the source rocks are very clearly diverse under different environments,which results in the significant differences in the proved reserves between the north and the *** order to further explore the differences in the hydrocarbon generation capacity of the source rocks under distinct depositional environments and the mechanism of their occurrence,three samples from different depositional environments(W18-5 for SE,H7-18 for BE,CH9 for FE)were used for confined gold tube pyrolysis *** results show that the CH4 yields of W18-5,H7-18 and CH9 increase with increasing temperature,the maximum yields being 405.62 mg/g TOC,388.56 mg/g TOC and 367.89 mg/g TOC,*** liquid hydrocarbon yields of W18-5,H7-18 and CH9 firstly increase with increasing temperature and then decrease after the critical *** maximum yields of C6-14 are 149.54 mg/g TOC,140.18 mg/g TOC and 116.94 mg/g TOC,the maximum yields of C14+being 852.4 mg/g TOC,652.6 mg/g TOC and 596.41 mg/g TOC,respectively for W18-5,H7-18 and *** summarize,the order of hydrocarbon potential from high to low is W18-5,H7-18 and *** this basis,through analyzing the influencing factors of hydrocarbon differences,this paper reveals that the saltwater environment is characterized by 4 factors:higher salinity,halophilic algae,high paleo-productivity and a strongly

关键词： sapropelite exinite gold-tube pyrolysis experiment hydrocarbon generation evolutionary model Dongpu Depression Bohai Bay Basin

Pilot Test for Nitrogen Foam Flooding in Low Permeability Reservoir

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Energy Engineering 2023年第3期120卷 763-774页

作者： Xinyu zhou Jia huang Yuchen Qian wenli Luo Lisha Qi Jie Wang Zhibin jiang Hao Kang State Key Laboratory of Enhanced Oil Recovery CNPCBeijing100083China Research Institute of Petroleum Exploration and Development CNPCBeijing100083China Research Institute of Petroleum Exploration and Development Xinjiang Oilfield CompanyKaramay834000China Hebei Normal University Shijiazhuang050024China

Due to the characteristics of reservoir formation,the producing level of low permeability reservoir is relatively very *** is hard to obtain high recovery through conventional development *** the tight matrix,complex fracture system,low production level of producers,and low recovery factor ofMblock in Xinjiang oilfield,it is selected for on-site pilot test of nitrogen foam *** flooding scheme is made and the test results are evaluated respectively both for producers and *** pressure index,filling degree,and fluid injection profile are found to be all improved in injectors after injection of nitrogen *** oil production,water cut and liquid production file are also improved in most of the producers,with the natural decline rate in the test area become *** show that nitrogen foam flooding technology can be good technical storage for enhanced oil recovery in low permeability reservoir.

关键词： Fluid production profile nitrogen foam low permeability pilot test

盆腔炎性疾病和子宫内膜异位症之间的因果关系:一项两样本双向孟德尔随机化研究

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中国优生与遗传杂志 2024年第8期32卷 1745-1751页

作者：毛雨瑞乔江唐佩郭清钟仪周子琪王淳黄雯丽唐嘉利雷磊湖南中医药大学第一中医临床学院湖南长沙410007 湖南中医药大学第一附属医院湖南长沙410007 湖南中医药大学湖南长沙410208

目的利用两样本双向孟德尔随机化(MR)分析盆腔炎性疾病(PID)与子宫内膜异位症(EMs)之间的潜在因果关系。方法从公开发表的全基因组关联数据库中筛选与PID和EMs有关的单核苷酸多态性(SNP)作为工具变量,双向分析均以逆方差加权法(IVW)分... 详细信息

目的利用两样本双向孟德尔随机化(MR)分析盆腔炎性疾病(PID)与子宫内膜异位症(EMs)之间的潜在因果关系。方法从公开发表的全基因组关联数据库中筛选与PID和EMs有关的单核苷酸多态性(SNP)作为工具变量,双向分析均以逆方差加权法(IVW)分析为主,MR-Egger回归、加权中位数法(WME)、简单模型、加权模型作为补充,并运用Cochrane’sQ检验、MR-Egger截距法、MR-PRESSO、留一法等进行敏感性分析确保结果的稳健性。结果共筛选得到20个与PID相关的SNP,5个与EMs相关的SNP,正向孟德尔随机化IVW结果:OR=1.073,95%CI:1.005~1.146,P=0.033,且不存在异质性和水平多效性(P均>0.05),结果具有稳健性;反向MR分析IVW结果:OR=1.666,95%CI:1.215~2.283,P=1.493×10^(-3),异质性检验P均>0.05;MR-Egger、MR-PRESSO检验并剔除离群值后分析结果P>0.05,可证明不存在异质性和水平多效性。结论本研究从遗传学角度分析表明PID与EMs互为因果关系,可能具有相似的发病机制。

关键词：盆腔炎性疾病孟德尔随机化子宫内膜异位症因果关系

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无源循环平稳信号检测方法

信号处理 2005年第6期21卷 597-599,569页

作者：姜文利黄知涛周一宇国防科技大学电子科学与工程学院长沙410073

研究了无源接收条件下循环平筝信号的检测方法。在循环相关匹配滤波理论的基础上,分别给出了无源单站和无源双站准循环相关匹配滤波器的设计方法,并研究了基于准循环相关匹配滤波的无源单站和无源双站信号检测方法,得到了SPS无源单站... 详细信息

研究了无源接收条件下循环平筝信号的检测方法。在循环相关匹配滤波理论的基础上,分别给出了无源单站和无源双站准循环相关匹配滤波器的设计方法,并研究了基于准循环相关匹配滤波的无源单站和无源双站信号检测方法,得到了SPS无源单站信号循环检测子和SPB无源双站信号循环检测子。仿真分析针对BPSK信号给出了在白噪声和时变噪声两种噪声背景条件下SPS、SPB和radiometry等检测子的ROC检测曲线,仿真结果充分说明了SPS和SPB检测子的有效性。

关键词：循环相关匹配滤波信号截获循环检测子能量辐射计

Life cycle assessment of biofuel production from microalgae cultivated in anaerobic digested wastewater

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International Journal of Agricultural and Biological Engineering 2020年第1期13卷 241-246页

作者： Gang Li zhitao Lu jiang Zhang Huan Li Yuguang zhou Ali Mohammed Ibrahim Zayan Zhigang huang School of Material Science and Mechanical Engineering Beijing Technology and Business UniversityBeijing 100048China Bioenergy and Environment Science&Technology Laboratory College of EngineeringChina Agricultural UniversityBeijing 100083China Key Laboratory of Clean Production and Utilization of Renewable Energy Ministry of Agriculture and Rural AffairsBeijing 100083China National Center for International Research of BioEnergy Science and Technology Ministry of Science and TechnologyBeijing 100083China Department of Agricultural Engineering Faculty of AgricultureOmdurman Islamic UniversityOmdurman ProvinceKhartoum StateSudan

The whole process of biofuel production from Desmodesmus *** 8-10 cultivated in anaerobic digested wastewater(ADW)under the optimal temperature was evaluated by using the method of Life Cycle Assessment(LCA).The energy efficiency and environment emissions were under considerable for the corresponding parametric *** functional unit was 1 kg *** was concluded that the harvest stage was responsible for the main energy consumption during the microalgal whole pyrolysis *** energy conversion efficiency of the whole process was larger than 1,which indicated that the process was *** environmental impact of the whole process was 1165.67 mPET2000,among which the primary impact on the environment was eutrophication that accounts for 57.36%,followed by photochemical ozone synthesis(22.56%),acidification(17.36%);and global warming(2.73%),respectively.

关键词： microalgae fast pyrolysis life cycle assessment(LCA) anaerobic digested wastewater(ADW) biofuel production

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基于加权AVA的SVM辐射源识别算法研究

信号处理 2006年第3期22卷 357-360页

作者：张国柱黄可生周一宇姜文利国防科大电子科学与工程学院湖南长沙410073

支持向量机(SVM)最初是用以解决两类分类问题,不能直接用于多类分类,如何有效地将其推广到多类分类问题是一个正在研究的问题。该文总结了现有主要的支持向量机多类分类算法,分析比较了各算法的分类精度,同时对其中一类方法进行了改进... 详细信息

支持向量机(SVM)最初是用以解决两类分类问题,不能直接用于多类分类,如何有效地将其推广到多类分类问题是一个正在研究的问题。该文总结了现有主要的支持向量机多类分类算法,分析比较了各算法的分类精度,同时对其中一类方法进行了改进。最后,把本文方法用于辐射源识别问题的解决,实际仿真结果表明该方法是有效的。

关键词：模式识别辐射源支持向量机多类分类

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一种变信噪比条件下的恒虚警野值检测方法

航空学报 2016年第7期37卷 2259-2268页

作者：汝小虎柳征姜文利黄知涛国防科学技术大学电子科学与工程学院长沙410073

野值检测又称异常值检测,是模式识别、机器智能和知识发现等领域经常面临的一个问题。当出现环境失配,数据信噪比(SNR)发生变化时,测试样本和训练样本所含噪声会有不同方差,以往的野值检测方法在虚警控制方面将会失效。针对这一问题,提... 详细信息

野值检测又称异常值检测,是模式识别、机器智能和知识发现等领域经常面临的一个问题。当出现环境失配,数据信噪比(SNR)发生变化时,测试样本和训练样本所含噪声会有不同方差,以往的野值检测方法在虚警控制方面将会失效。针对这一问题,提出一种基于归一化残差(NR)的野值检测方法。该方法首先根据所需虚警概率和噪声方差变化情况确定野值检测门限,其次基于训练样本计算待考查模式的NR值,再比较NR值与检测门限的相对大小,从而判断待考查模式是否为野值。这一方法所依赖的检测门限对所需虚警率和噪声方差变化具有适应能力,因此可以在变信噪比条件下实现恒虚警(CFAR)野值检测。仿真实验验证了所提方法在虚警控制和野值检测方面的优越性能。

关键词：模式识别野值检测恒虚警虚警概率归-化残差

基于Sub-Nyquist采样的单通道频谱感知技术

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国防科技大学学报 2013年第4期35卷 121-127页

作者：杨鹏樊昀黄知涛柳征姜文利国防科技大学电子科学与工程学院湖南长沙410073 北京947信箱北京100005

宽带频谱感知技术在认知无线电中具有广泛的应用。基于时分的思想,将信号采集时间以固定长度的时间片进行划分,分别与不同的伪随机码信号相乘,经过低通滤波和sub-Nyquist采样,利用采样数据求出信号的频率支集。与已有的多通道频谱感知... 详细信息

宽带频谱感知技术在认知无线电中具有广泛的应用。基于时分的思想,将信号采集时间以固定长度的时间片进行划分,分别与不同的伪随机码信号相乘,经过低通滤波和sub-Nyquist采样,利用采样数据求出信号的频率支集。与已有的多通道频谱感知结构相比,本文用相对简单的单通道结构实现,同样能够利用低速率的采样点完成频谱感知。仿真实验结果表明,在信号的频率支集未知的情况下,该算法能够有效利用sub-Nyquist采样的数据实现频谱感知。

关键词：时分 sub-Nyquist采样单通道频谱感知认知无线电