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Multi-feature Multimodal Biometric Recognition Based on Quaternion Locality Preserving Projection

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Chinese Journal of Electronics 2019年第4期28卷 789-796页

作者： WANG Zhifang ZHEN Jiaqi li yanchao li Guoqiang HAN Qi Department of Electronic Engineering Heilongjiang University Department of Information Security and Communication Technology Norwegian University of Science and Technology Department of Computer Science and Technology Harbin Institute of Technology

This paper proposed Quaternion locality preserving projection(QLPP) for multi-feature multimodal biometric recognition. Multi-features fill the real part or the three imaginary parts of quaternion to constitute the quaternion fusion features. In quaternion division ring, QLPP extracts the local information and finds essential manifold structure of the quaternion fusion features. Deferent from Quaternion principal component analysis(QPCA) and Quaternion fisher discriminant analysis(QFDA), QLPP takes advantage of the optimal linear approximations to find the nonlinear manifold structures. Two experiments are designed: one fuses four features from two biometric modalities, and the other fuses three features from three biometric *** experimental results show the proposed algorithm achieves much better performance than the unimodal biometric algorithms, the traditional feature level fusion methods(weighted sum rule and series rule) and two quaternion representation methods(QPCA and QFDA).

关键词： Multimodal biometrics Quaternion Feature fusion Quaternion locality preserving projection(QLPP)

Beagle Dogs Have Low Susceptibility to Florida Clade 2 H3N8 Equine Avian Influenza

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Virologica Sinica 2021年第5期36卷 1248-1251页

作者： Pei Zhou Xiangyu Xiao Xinkai Hu Jie Dong Haoyao Zhang yanchao li Shoujun li Guangdong Provincial Key Laboratory of Comprehensive Prevention and Control for Severe Clinical Animal Diseases College of Veterinary MedicineSouth China Agricultural UniversityGuangzhou 510642China Guangdong Technological Engineering Research Center for Pets College of Veterinary MedicineSouth China Agricultural UniversityGuangzhou 510642China

Dear Editor,Dogs were long considered refractory to influenza viruses until the equine-origin H3N8 canine influenza virus(CIV)was first isolated in the United States of America(U.S.A)in 2004(Crawford et al.2005).Since then,H3N8 CIV of equine-origin strains has been circulating in dogs in the *** 2006,another CIV of avian origin H3N2 subtype was isolated from dogs in China(li et al.2010).Recently,H3N2 CIV strains have become endemic in dog populations in China,South Korea,and North America(Borland et al.2020).

关键词： H3N8 H3N2 Avian

Radial Permeability Measurements for Shale Using Variable Pressure Gradients

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Acta Geologica Sinica(English Edition) 2020年第2期94卷 269-279页

作者： FAN Kunkun SUN Renyuan DEREK ELS WORTH DONG Mingzhe li Yajun YIN Congbin li yanchao CHEN Zhongwei WANG Chunguang State Key Laboratory of Mining Disaster Prevention and Control Shandong University of Science and TechnologyQingdao 266555China College of Energy and Mining Engineering.Shandong University of Science and Techology.Qingdao 266555 China College of Petroleum Engineering Chinese University of PetroleumQingdao 266555ShandongChina Energy and Mineral Engineering Pennsylvania State University PA 16X01USA Department of Chemical and Petroleum Engineering University of CalgaryAB T2NIN4Canada Downhole Service Company.Chuanqing Drilling Company CNPCChengdu 610051SichuanChina School of Mechanical and Mining Engineering The University of QueenslandQLD 4074Australia

Shale gas is becoming an important component of the global energy supply, with permeability a critical controlling factor for long-term gas production. Obvious deviation may exist between helium permeability determined using small pressure gradient(SPG) methods and methane permeability obtained under actual field production with variable pressure gradients(VPG). In order to more accurately evaluate the matrix permeability of shale, a VPG method using real gas(rather than He) is established to render permeability measurements that are more representative of reservoir conditions and hence response. Dynamic methane production experiments were performed to measure permeability using the annular space in the shale cores. For each production stage, boundary pressure is maintained at a constant and the gas production with time is measured on the basis of volume change history in the measuring pump. A mathematical model explicitly accommodating gas desorption uses pseudo-pressure and pseudo-time to accommodate the effects of variations in pressuredependent PVT parameters. Analytical and semi-analytical solutions to the model are obtained and discussed. These provide a convenient approach to estimate radial permeability in the core by nonlinear fitting to match the semi-analytical solution with the recorded gas production data. Results indicate that the radial permeability of the shale determined using methane is in the range of 1×10-6– 1×10-5 mD and decreases with a decrease in average pore pressure. This is contrary to the observed change in permeability estimated using helium. Bedding geometry has a significant influence on shale permeability with permeability in parallel bedding orientation larger than that in perpendicular bedding orientation. The superiority of the VPG method is confirmed by comparing permeability test results obtained from both VPG and SPG methods. Although several assumptions are used, the results obtained from the VPG method with reservoir gas are m

关键词： shale radial permeability variable pressure gradients pseudo pressure pseudo time

An Analysis of the Static and Dynamic Behavior of the Hydraulic Compensation System of a Multichannel Valve

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Fluid Dynamics & Materials Processing 2023年第7期19卷 1817-1836页

作者： Jikang Xu Ruichuan li Yi Cheng yanchao li Junru Yang Chenyu Feng Xinkai Ding Huazhong Zhang College of Transportation Shandong University of Science and TechnologyQingdao266590China School of Mechanical and Automotive Engineering Qilu University of TechnologyJinan250353China College of Mechanical and Electronic Engineering Shandong University of Science and TechnologyQingdao266590China Rizhao Haizhuo Hydraulic Co. Ltd.Rizhao276800China Rizhao Polytechnic Rizhao276800China

Electro-hydraulic proportional valve is the core control valve in many hydraulic systems used in agricultural and engineering *** address the problem related to the large throttling losses and poor stability typically associated with these valves,here,the beneficial effects of a triangular groove structure on the related hydraulic response are studied.A mathematical model of the pressure compensation system based on the power-bond graph method is introduced,and the AMESim software is used to simulate its *** results show that the triangular groove structure increases the jet angle and effectively compensates for the hydrodynamic *** steady-state differential pressure at the valve port of the new pressure compensation structure was 0.65 ***,experimental results show that the pressure difference at the main valve port is 0.73 MPa,and that the response time is less than 0.2 *** is concluded that the new compensation structure has good pressure compensation response characteristics.

关键词： Electrohydraulic proportional valve spool shape pressure compensation valve port differential pressure response time

Simulation Method and Feature Analysis of Shutdown Pressure Evolution During Multi-Cluster Fracturing Stimulation

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Energy Engineering 2024年第1期121卷 111-123页

作者： Huaiyin He Longqing Zou yanchao li Yixuan Wang Junxiang li Huan Wen Bei Chang lijun liu Shale Gas Exploration and Development Department CNPC Chuanqing Drilling Engineering Co.Ltd.Chengdu610051China College of Energy Chengdu University of TechnologyChengdu610059China

Multistage multi-cluster hydraulic fracturing has enabled the economic exploitation of shale reservoirs,but the interpretation of hydraulic fracture parameters is *** pressure signals after pump shutdown are influenced by hydraulic fractures,which can reflect the geometric features of hydraulic *** shutdown pressure can be used to interpret the hydraulic fracture parameters in a real-time and cost-effective *** this paper,a mathematical model for shutdown pressure evolution is developed considering the effects of wellbore friction,perforation friction and fluid loss in *** efficient numerical simulation method is established by using the method of *** on this method,the impacts of fracture half-length,fracture height,opened cluster and perforation number,and filtration coefficient on the evolution of shutdown pressure are *** results indicate that a larger fracture half-length may hasten the decay of shutdown pressure,while a larger fracture height can slow down the decay of shutdown pressure.A smaller number of opened clusters and perforations can significantly increase the perforation friction and decrease the overall level of shutdown pressure.A larger filtration coefficient may accelerate the fluid filtration in the fracture and hasten the drop of the shutdown *** simulation method of shutdown pressure,as well as the analysis results,has important implications for the interpretation of hydraulic fracture parameters.

关键词： Multistage multi-cluster hydraulic fracturing pump shutdown pressure feature analysis numerical simulation

Fluorinated poly(p-triphenylene isatin) anion exchange membranes based on hydrophilic hydroxyl side chain modulation for fuel cells

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Journal of Energy Chemistry 2025年第1期100卷 702-709页

作者： Yiman Gu yanchao Zhang Zhanyu li Yijia Lei Baozeng Sun Xiaoyu Yu Zhe Wang College of Chemistry and life Science Changchun University of Technology College of Chemical Engineering Changchun University of Technology School of Materials Science and Engineering Changchun University of Technology Key Laboratory of Advanced Functional Polymer Membrane Materials of Jilin Province

The development of alkaline fuel cells is moving forward at an accelerated pace,and the application of ether-free bonded polymers to anion exchange membranes （AEMs） has been widely ***,the question of the“trade-off”between AEM ionic conductivity and dimensional stability remains *** strategy of inducing microphase separation to improve the performance of AEM has attracted much attention recently,but the design of optimal molecular structures is still being ***,this work introduced different ratios of 3-bromo-1,1,1-trifluoroacetone （x=40,50,and 60） into the main chain of poly（p-terphenylene isatin）.Because fluorinated groups have excellent hydrophobicity,hydrophilic hydroxyl-containing side chains are introduced to jointly adjust the formation of phase separation *** results show that PTI-PTF50-NOH AEM with the appropriate fluorinated group ratio has the best ionic conductivity and alkali stability under the combined effect of *** has an ionic conductivity of 133.83 mS cm-1at 80°*** addition,the OH-conductivity remains at 89%of the initial value at 80°C and 3 M KOH for 1056 h of *** cell polarization curve based on PTI-PTF50-NOH shows a power density of 734.76 mW cm-2at a current density of 1807.7 mA cm-2.

关键词： Anion exchange membranes Poly(p-terphenylene isatin) Hydrophilic-hydrophobic phase separation Fluorinated group

基于空芯带隙型光子晶体光纤的单端置入式同源甲烷检测仪

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中国激光 2020年第1期47卷 304-311页

作者：丛海芳李彦超长春理工大学电子信息工程学院吉林长春130022 黑龙江大学电子工程学院黑龙江哈尔滨150080

为了提高复杂环境中甲烷气体探测的适用性,选择空芯带隙型光子晶体光纤(单端镀全反膜)作为光学气室,实现了置入式同源甲烷浓度的探测。采用可调谐半导体激光吸收光谱(TDLAS)技术,结合长度为0.5 m的空芯带隙型光子晶体光纤,实现了甲烷气... 详细信息

为了提高复杂环境中甲烷气体探测的适用性,选择空芯带隙型光子晶体光纤(单端镀全反膜)作为光学气室,实现了置入式同源甲烷浓度的探测。采用可调谐半导体激光吸收光谱(TDLAS)技术,结合长度为0.5 m的空芯带隙型光子晶体光纤,实现了甲烷气体的在线测量,系统的检测下限可达到1.92×10^-5,稳定性波动小于±2.18%。单端全反射设计配合同源探测方式使复杂环境中的甲烷浓度的置入式探测成为可能,为单光源分布式探测提供了研究基础。

关键词：光谱学红外吸收光谱同源探测甲烷检测空芯带隙型光子晶体光纤

基于最小二乘支持向量机逆系统的五自由度无轴承同步磁阻电机解耦控制

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中国电机工程学报 2013年第15期33卷 99-108,10页

作者：朱熀秋曹莉李衍超刁小燕江苏大学电气信息工程学院江苏省镇江市212013

针对三自由度交直流混合磁轴承和二自由度无轴承同步磁阻电机构成的五自由度无轴承同步磁阻电机,实现磁轴承的径向悬浮力、轴向悬浮力、二自由度无轴承同步磁阻电机的径向悬浮力和电磁转矩的解耦控制是五自由度无轴承同步磁阻电机稳定... 详细信息

针对三自由度交直流混合磁轴承和二自由度无轴承同步磁阻电机构成的五自由度无轴承同步磁阻电机,实现磁轴承的径向悬浮力、轴向悬浮力、二自由度无轴承同步磁阻电机的径向悬浮力和电磁转矩的解耦控制是五自由度无轴承同步磁阻电机稳定运行和精确控制的必要条件。该文在介绍五自由度无轴承同步磁阻电机基本结构的基础上,建立了三自由度交直流混合磁轴承和二自由度无轴承同步磁阻电机的数学模型,进而建立了五自由度无轴承同步磁阻电机的状态方程,并进行了可逆性分析。采用最小二乘支持向量机所具有的小样本逼近和辨识拟合能力,得到五自由度无轴承同步磁阻电机逆模型,根据逆系统方法的基本原理,将复杂的原非线性多变量耦合系统解耦成多个单输入单输出伪线性系统,并设计了闭环PID控制器。仿真和实验表明,电机具有良好的速度和悬浮特性,这种解耦方法能够实现五自由度无轴承同步各个被控量之间的动态解耦,并且系统具有良好的动静态性能。

关键词：无轴承同步磁阻电机磁轴承逆系统最小二乘支持向量机解耦控制

新制度主义视野下我国草根体育组织发展的制度困境与路径选择

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武汉体育学院学报 2018年第9期52卷 45-50页

作者：李延超上海体育学院经管学院上海200438

以新制度主义为理论基础,采用文献研究、逻辑分析等方法,分析了草根体育组织发展的制度困境,提出了草根体育组织发展路径选择。研究表明,我国草根体育组织面临着诸多制度困境:管制性制度不完善,导致其身份尴尬,缺乏归属感;规范性制度缺... 详细信息

以新制度主义为理论基础,采用文献研究、逻辑分析等方法,分析了草根体育组织发展的制度困境,提出了草根体育组织发展路径选择。研究表明,我国草根体育组织面临着诸多制度困境:管制性制度不完善,导致其身份尴尬,缺乏归属感;规范性制度缺失,导致其发展无序,内部运行紊乱;文化-认知制度薄弱,导致其价值迷失,公信力偏低。因此,应以体制改革增强其发展活力,以制度创新促进其规范化发展,以文化认同优化其发展环境。

关键词：草根体育组织生存发展制度困境路径选择新制度主义