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DOA estimation method for wideband signals by block sparse reconstruction

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Journal of Systems Engineering and Electronics 2016年第1期27卷 20-27页

作者： Jiaqi Zhen zhifang wang College of Electronic Engineering Heilongjiang University

For the direction of arrival（DOA） estimation,traditional sparse reconstruction methods for wideband signals usually need many iteration *** this problem,a new method for two-dimensional wideband signals based on block sparse reconstruction is ***,a prolate spheroidal wave function（PSWF） is used to fit the wideband signals,then the block sparse reconstruction technology is employed for DOA *** proposed method uses orthogonalization to choose the matching atoms,ensuring that the residual components correspond to the minimum absolute ***,the vectors obtained by iteration are back-disposed according to the corresponding atomic matching rules,so the extra atoms are abandoned in the course of iteration,and the residual components of current iteration are *** the original sparse signals are *** proposed method reduces iteration times comparing with the traditional reconstruction methods,and the estimation precision is better than the classical two-sided correlation transformation（TCT）algorithm when the snapshot is small or the signal-to-noise ratio（SNR） is low.

关键词： direction of arrival(DOA)estimation wideband signal prolate spheroidal wave function(PSWF) block sparse reconstruction.

DOA estimation method for wideband signals by sparse recovery in frequency domain

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Journal of Systems Engineering and Electronics 2017年第5期28卷 871-878页

作者： Jiaqi Zhen zhifang wang College of Electronic Engineering Heilongjiang University

The traditional super-resolution direction finding methods based on sparse recovery need to divide the estimation space into several discrete angle grids, which will bring the final result some error. To this problem, a novel method for wideband signals by sparse recovery in the frequency domain is proposed. The optimization functions are found and solved by the received data at every frequency, on this basis, the sparse support set is obtained, then the direction of arrival (DOA) is acquired by integrating the information of all frequency bins, and the initial signal can also be recovered. This method avoids the error caused by sparse recovery methods based on grid division, and the degree of freedom is also expanded by array transformation, especially it has a preferable performance under the circumstances of a small number of snapshots and a low signal to noise ratio (SNR).

关键词： super-resolution direction of arrival sparse recovery frequency domain wideband signals

基于深度算法的肝外胆管癌术前MRI动态增强扫描自动分期系统的构建及验证

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齐齐哈尔医学院学报 2025年第2期46卷 141-146页

作者：时金凤王志芳濮阳油田总医院放射科河南濮阳457001

目的基于深度学习算法构建肝外胆管癌(ECC)术前磁共振成像(MRI)动态增强扫描自动分期系统,并验证其效能。方法回顾性分析2020年1月-2022年12月本院收治的270例ECC患者的临床资料,作为训练集,收集其经MRI动态增强扫描获得的肿瘤位置、侵... 详细信息

目的基于深度学习算法构建肝外胆管癌(ECC)术前磁共振成像(MRI)动态增强扫描自动分期系统,并验证其效能。方法回顾性分析2020年1月-2022年12月本院收治的270例ECC患者的临床资料,作为训练集,收集其经MRI动态增强扫描获得的肿瘤位置、侵犯范围、淋巴结转移等特征,基于深度学习算法对不同临床分期的ECC进行分类建模,构建ECC术前MRI动态增强扫描自动分期系统。另回顾性分析2023年1-12月本院收治的94例ECC患者临床资料作为验证集,以病理学诊断的临床分期结果作为金标准,分析基于深度算法的ECC术前MRI动态增强扫描自动分期系统对患者临床分期的诊断效能。结果基于深度学习算法的ECC术前MRI动态增强扫描自动分期系统对临床分期Ⅰ期、Ⅱ期、Ⅲ期、Ⅳ期的诊断灵敏度(100.00%、93.33%、97.78%、100.00%)、特异度(100.00%、98.44%、95.92%、100.00%)和准确度(100%、96.81%、96.81%、100.00%)高于MRI动态增强扫描检查方式(灵敏度:91.67%、86.67%、88.89%、85.71%,特异度:97.56%、90.63%、93.88%、100.00%,准确度:96.81%、89.36%、91.49%、98.94%),且与病理学结果的一致性高(Kappa=0.885,P<0.001),MRI动态增强扫描检查方式与病理学结果也存在一致性(Kappa=0.691,P<0.001)。结论基于深度学习算法构建的ECC术前MRI动态增强扫描自动分期系统可提高对ECC术前分期的诊断敏感度、特异度和准确度。

关键词：深度学习算法肝外胆管癌磁共振成像动态增强扫描

Quaternion Kernel Fisher Discriminant Analysis for Feature-Level Multimodal Biometric Recognition

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Chinese Journal of Electronics 2020年第6期29卷 1085-1092页

作者： wang zhifang ZHEN Jiaqi ZHU Fuzhen HAN Qi Department of Electronic Engineering Heilongjiang University Department of Computer Science and Technology Harbin Institute of Technology

Quaternion kernel Fisher discriminant analysis(QKFDA) is proposed for feature level multimodal biometric *** quaternion division ring,QKFDA extracts the most discriminative information from the quaternion fusion feature sets by maximizing the betweenclass variance while minimizing the within-class variance.A complete two-phases framework of QKFDA is developed:Quaternion kernel principal component analysis(QKPCA)plus Quaternion linear discriminant analysis(QLDA).Two experiments are designed:experiment Ⅰ fuses four different features of face and plamprint,experiment Ⅱ fuses three different features of face,plamprint and *** experimental results show that QKFDA is superior to both traditional feature fusion methods(series rule and weighted sum rule)and other quaternion feature fusion methods(QPCA,QFDA,QLPP and QKPCA).

关键词： biometrics (access control) face recognition feature extraction image fusion principal component analysis plamprint feature face feature fusion quaternion feature fusion methods QLDA quaternion linear discriminant analysis QKPCA QLPP QFDA QPCA quaternion kernel principal component analysis quaternion kernel Fisher discriminant analysis quaternion fusion feature sets discriminative information quaternion division ring feature level multimodal biometric recognition QKFDA Quaternion division ring Quaternion kernel Fisher discriminant analysis (QKFDA) Multimodal biometrics Feature fusion

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)

Mechanical Properties of a Eucalyptus-Based Oriented Oblique Strand Lumber for Structural Applications

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Journal of Renewable Materials 2019年第11期7卷 1147-1164页

作者： Jiawei Chen Haibei Xiong zhifang wang Linqing Yang College of Civil Engineering Tongji UniversityShanghai200092China Shenzhen Plantation Material Technology Co. Ltd.Shenzhen518055China

Wood and wood-based composite materials have gained increasing attention in the sustainable building industry because of their renewability and environmental *** oblique strand lumber(Eucalyptus Strand Wood,ESWood),which is manufactured from fast-growing small diameter eucalyptus wood(Eucalyptus urophylla×***),is introduced in this *** clear specimen tests were conducted to determine the mechanical properties of ESWood material while full-scale component tests were performed to observe the structural performance of ESWood beams.A comparison of mechanical properties of ESWood with other wood/bamboo-based materials is then *** the results presented herein,it appears that the strength and stiffness properties of ESWood are affected by grain directionality and glued ***,it still has preferable mechanical properties as a building material,which is comparable or superior to those of other engineered wood/bamboo-based products(e.g.,Sitka spruce,LVL,OSL,Glulam,and Glubam).Furthermore,results from full-scale component tests show the stable mechanical performance of beams made by *** study makes a significant contribution to a potential utilization of fast-growing eucalyptus for general use in construction,and the presented mechanical tests results can serve as a fundamental data for more applications of ESWood in practical engineering.

关键词： Wood-based composite material mechanical properties eucalyptus experimental test construction material

Interactions among SARS-CoV accessory proteins revealed by bimolecular fluorescence complementation assay

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Acta Pharmaceutica Sinica B 2015年第5期5卷 487-492页

作者： Jianqiang Kong Yanwei Shi zhifang wang Yiting Pan State Key Laboratory of Bioactive Substance and Function of Natural Medicines & Ministry of Health Key Laboratory of Biosynthesis of Natural Products Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College aState Key Laboratory of Bioactive Substance and Function of Natural Medicines & Ministry of Health Key Laboratory of Biosynthesis of Natural Products Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College School of Chemical Engineering Beijing Institute of Petrochemical Technology

The accessory proteins(3a, 3b, 6, 7a, 7b, 8a, 8b, 9b and ORF14), predicted unknown proteins(PUPs) encoded by the genes, are considered to be unique to the severe acute respiratory syndrome coronavirus(SARS-Co V) genome. These proteins play important roles in various biological processes mediated by interactions with their partners. However, very little is known about the interactions among these accessory proteins. Here, a EYFP(enhanced yellow fluorescent protein) bimolecular fluorescence complementation(BiFC) assay was used to detect the interactions among accessory proteins. 33 out of 81 interactions were identified by BiFC, much more than that identified by the yeast two-hybrid(Y2H)system. This is the first report describing direct visualization of interactions among accessory proteins of SARS-CoV. These findings attest to the general applicability of the BiFC system for the verification of protein-protein interactions.

关键词： SARS-CoV Accessory proteins Y2H Bimolecular fluorescence complementation assay

京津冀文化、体育和旅游产业与国民经济各产业关联关系及其演化——基于中国区域间投入产出表的测算

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大理大学学报 2025年第1期10卷 32-43页

作者：焦莉莉王志芳张丹河北地质大学经济学院石家庄050031 商务部国际贸易经济合作研究院北京100710

新发展格局下,京津冀协同发展是国家区域发展战略的重要一环。三地产业协同发展是区域一体化的核心动力。当前,文化、体育和旅游产业融合与协同已成为京津冀区域发展的重要力量和抓手。基于2012年和2017年中国区域间投入产出表,从国民... 详细信息

新发展格局下,京津冀协同发展是国家区域发展战略的重要一环。三地产业协同发展是区域一体化的核心动力。当前,文化、体育和旅游产业融合与协同已成为京津冀区域发展的重要力量和抓手。基于2012年和2017年中国区域间投入产出表,从国民经济整体、三次产业和细分产业层面,对京津冀文化、体育和旅游产业与国民经济各部门的后向与前向关联关系及其演变特征进行分析。研究发现,京津冀文化、体育和旅游产业的影响力系数和感应度系数均呈上升趋势,但其影响力系数均高于感应度系数,属于需求拉动型而非供给推动型产业。对第一产业的后向和前向关联关系均较弱;对第二产业后向关联京津显著下降,河北明显上升,前向关联北京市和河北省显著下降,天津市明显上升;对第三产业后向关联均越来越强,前向产业关联北京大幅下降,津冀则明显上升,京津冀对国内租赁和商务服务、造纸印刷和文教体育用品、文化、体育和旅游产品等八类产业均有较高后向依赖。北京市倾向于文化、体育和旅游产业、公共管理等服务部门的前向供给,而天津市和河北省则更多倾向于金属冶炼和压延产品、化学产品等制造业部门前向供给。研究对京津冀区域发展战略的推进和政策制定具有重要意义,不仅为京津冀文化、体育和旅游产业的高质量发展提供了科学的数据支撑,同时也为京津冀及我国其他区域协同发展战略的实施提供有益的决策参考。

关键词：京津冀文化、体育和旅游产业投入产出关联关系

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粗纱定量对赛络集聚纺成纱质量的影响

纺织器材 2025年第1期52卷 36-38页

作者：王志方侯英华高广远夏津仁和纺织科技有限公司山东德州253200

为了探讨粗纱定量对赛络集聚纺成纱质量的影响,通过在不同粗纱定量下试纺赛络集聚纺R/G10011.7 tex混纺纱、CJ/M 50/5011.7 tex混纺纱及LF 9.8 tex纱,对比分析粗纱定量对成纱质量、生产成本等的影响。指出:在后区牵伸倍数不变的条件下,... 详细信息

为了探讨粗纱定量对赛络集聚纺成纱质量的影响,通过在不同粗纱定量下试纺赛络集聚纺R/G10011.7 tex混纺纱、CJ/M 50/5011.7 tex混纺纱及LF 9.8 tex纱,对比分析粗纱定量对成纱质量、生产成本等的影响。指出:在后区牵伸倍数不变的条件下,随着粗纱定量增大,3种赛络集聚纺品种的成纱质量指标变差;小的粗纱定量有利于纺纱质量和节约吨纱用电,实际生产中粗纱定量应结合纺纱品种、生产条件等进行优选。

关键词：粗纱定量赛络集聚纺隔距块牵伸成纱强力条干吨纱用电