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Enhance the Performance of Directional Feature-based Palmprint Recognition by Directional Response Stability Measurement

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Machine Intelligence Research 2024年第3期21卷 597-614页

作者： Haitao Wang Wei jia School of Computer Science and Information Engineering Hefei University of TechnologyHefei230009China

Palmprint recognition is an emerging biometrics technology that has attracted increasing attention in recent years. Many palmprint recognition methods have been proposed, including traditional methods and deep learning-based methods. Among the traditional methods, the methods based on directional features are mainstream because they have high recognition rates and are robust to illumination changes and small noises. However, to date, in these methods, the stability of the palmprint directional response has not been deeply studied. In this paper, we analyse the problem of directional response instability in palmprint recognition methods based on directional feature. We then propose a novel palmprint directional response stability measurement (DRSM) to judge the stability of the directional feature of each pixel. After filtering the palmprint image with the filter bank, we design DRSM according to the relationship between the maximum response value and other response values for each pixel. Using DRSM, we can judge those pixels with unstable directional response and use a specially designed encoding mode related to a specific method. We insert the DRSM mechanism into seven classical methods based on directional feature, and conduct many experiments on six public palmprint databases. The experimental results show that the DRSM mechanism can effectively improve the performance of these methods. In the field of palmprint recognition, this work is the first in-depth study on the stability of the palmprint directional response, so this paper has strong reference value for research on palmprint recognition methods based on directional features.

关键词： Biometrics palmprint recognition directional response stability directional coding-based methods directional feature

纳米羟基磷灰石/聚己内酯复合生物活性多孔支架研究

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无机材料学报 2009年第3期24卷 485-490页

作者：苏佳灿李明禹宝庆张春才上海市第二军医大学附属长海医院骨科上海200433

采用水热法制备了纳米羟基磷灰石（n-HA）及其与聚己内酯（PCL）的复合材料.用熔融浇铸/食盐微粒浸出法制备了孔径在200~400μm、大孔互相贯通的复合材料支架.通过细胞培养和体内动物实验研究了该支架的生物学性能.结果表明,复合支架的... 详细信息

采用水热法制备了纳米羟基磷灰石（n-HA）及其与聚己内酯（PCL）的复合材料.用熔融浇铸/食盐微粒浸出法制备了孔径在200~400μm、大孔互相贯通的复合材料支架.通过细胞培养和体内动物实验研究了该支架的生物学性能.结果表明,复合支架的孔隙率随致孔剂用量的增加而增加,而抗压强度随之而减小;支架的最大孔隙率可达86%,相应的抗压强度为2.4MPa.成骨细胞在支架上的细胞粘附率和增殖随磷灰石含量增加而提高,复合材料明显高于单纯的PCL支架.组织学观察显示,新生骨长入多孔支架和复合材料形成了直接的骨性结合.n-HA/PCL复合材料支架有很好的生物相容性和生物活性.

关键词：纳米羟基磷灰石聚己内酯复合材料组织工程支架生物活性

Fractures interaction and propagation mechanism of multi-cluster fracturing on laminated shale oil reservoir

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Petroleum Science 2024年第4期21卷 2600-2613页

作者： jia-Xin Lv Bing Hou Key Laboratory of Petroleum Engineering Ministry of Education China University of Petroleum (Beijing) State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum (Beijing) Department of Petroleum Engineering China University of Petroleum (Beijing) at Karamay

The continental shale reservoirs of Jurassic Lianggaoshan Formation in Sichuan Basin contain thin lamina, which is characterized by strong plasticity and developed longitudinal shell limestone *** improve the production efficiency of reservoirs by multi-cluster fracturing, it is necessary to consider the unbalanced propagation of hydraulic fractures and the penetration effect of fractures. This paper constructed a numerical model of multi-fracture propagation and penetration based on the finite element coupling cohesive zone method; considering the construction cluster spacing, pump rate,lamina strength and other parameters studied the influencing factors of multi-cluster fracture interaction propagation; combined with AE energy data and fracture mode reconstruction method, quantitatively characterized the comprehensive impact of the strength of thin interlayer rock interfaces on the initiation and propagation of fractures that penetrate layers, and accurately predicted the propagation pattern of hydraulic fractures through laminated shale oil reservoirs. Simulation results revealed that in the process of multi-cluster fracturing, the proportion of shear damage is low, and mainly occurs in bedding fractures activated by outer fractures. Reducing the cluster spacing enhances the fracture system's penetration ability, though it lowers the activation efficiency of lamina. The high plasticity of the limestone interlayer may impact the vertical propagation distance of the main fracture. Improving the interface strength is beneficial to the reconstruction of the fracture height, but the interface communication effect is limited. Reasonable selection of layers with moderate lamina strength for fracturing stimulation, increasing the pump rate during fracturing and setting the cluster spacing reasonably are beneficial to improve the effect of reservoir stimulation.

关键词： Laminated shale Multi-cluster fracturing Cross-layer Cohesive zone model Acoustic emission technique

Temporal and spatial regulation of biomimetic vascularization in 3D-printed skeletal muscles

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Bio-Design and Manufacturing 2024年第5期7卷 597-610页

作者： Minxuan jia Tingting Fan Tan jia Xin Liu Heng Liu Qi Gu Key Laboratory of Organ Regeneration and Reconstruction State Key Laboratory of Membrane BiologyInstitute of ZoologyChinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Stem Cell and Reproductive Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Department of Orthopaedics Beijing Jishuitan HospitalCapital Medical UniversityBeijing 100035China

In the intricate skeletal muscle tissue,the symbiotic relationship between myotubes and their supporting vasculature is pivotal in delivering essential oxygen and *** study explored the complex interplay between skeletal muscle and endothelial cells in the vascularization ofmuscle *** harnessing the capabilities of three-dimensional(3D)bioprinting and modeling,we developed a novel approach involving the co-construction of endothelial and muscle cells,followed by their subsequent *** findings highlight the importance of the interaction dynamics between these two cell ***,introducing endothelial cells during the advanced phases of muscle differentiation enhanced myotube ***,it stimulated the development of the vascular network,paving the way for the early stages of vascularized skeletal muscle *** methodology proposed in this study indicates the potential for constructing large-scale,physiologically aligned skeletal ***,it highlights the need for exploring the delicate equilibrium and mutual interactions between muscle and endothelial *** on the multicell-type interaction model,we can predict promising pathways for constructing even more intricate tissues or organs.

关键词： Skeletal muscle Vascularization 3D bioprinting Cell interaction

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先秦儒道礼学思想比较研究

华中科技大学学报（社会科学版） 2022年第6期36卷 19-26页

作者：张海英陈嘉灿湖南大学中国语言文学学院

先秦儒道礼学思想有几个本质不同之处,具体说来,儒家重视礼之文,道家重视礼之质,道家认为礼的形式本身不如礼的内容重要,即认为内容与形式,也就是文和质难以两全。儒家强调礼之等级差别,道家强调礼之平等。儒家强调行礼时服从社会和群体... 详细信息

先秦儒道礼学思想有几个本质不同之处,具体说来,儒家重视礼之文,道家重视礼之质,道家认为礼的形式本身不如礼的内容重要,即认为内容与形式,也就是文和质难以两全。儒家强调礼之等级差别,道家强调礼之平等。儒家强调行礼时服从社会和群体,道家提倡循性而动,率情而为。儒道礼学思想相异的原因首先是因为儒道两家对礼的界定不同,道家所界定的礼基本相当于儒家所界定的物质形态的礼。儒道政治观念和政治地位不同,对礼的对象认定的不同也会带来二者礼学思想的区别。

关键词：先秦儒家道家礼学

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南宋科举与社会流动的量化考察——以两份登科录为中心

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长江师范学院学报 2023年第6期39卷 120-128页

作者：贾灿灿南通大学文学院江苏南通226300

对《绍兴十八年同年小录》和《宝祐四年登科录》的统计发现:一方面,从绍兴十八年到宝祐四年,家世背景对登科举数、登科年龄的影响是逐渐减弱的。平民家庭出身者在两份登科录中始终占半数以上,表现出科举带来的社会流动性。但不可否认的... 详细信息

对《绍兴十八年同年小录》和《宝祐四年登科录》的统计发现:一方面,从绍兴十八年到宝祐四年,家世背景对登科举数、登科年龄的影响是逐渐减弱的。平民家庭出身者在两份登科录中始终占半数以上,表现出科举带来的社会流动性。但不可否认的是,家世背景能为登科者在上行道路上赢得更多的时间。另一方面,通过与南宋宰辅登科年龄的对比,可见宰辅在平均登科年龄上较两榜进士年轻化,官员家庭与平民家庭的平均登科年龄相差不大,显示出家世背景在平均登科年龄上的减弱。一言以蔽之,家庭因素在科举考试中的助力作用正在逐步降低,换言之,科举确实为南宋社会流动的加速起到推动作用,并促使南宋社会逐渐走向流动性和开放性的发展趋势。

关键词：南宋科举社会流动登科录

Structural engineered living materials

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Nano Research 2024年第2期17卷 715-733页

作者： Yang Geng Zian jia Ling Li 635 Prices Fork Road Department of Mechanical EngineeringVirginia Polytechnic Institute and State UniversityBlacksburg VA24061USA

Biological structural materials not only exhibit remarkable mechanical properties but also often embody dynamic characteristics such as environmental responsiveness,autonomy,and self-healing,which are difficult to achieve in conventional engineering *** merging materials science,synthetic biology,and other disciplines,engineered living materials(ELMs)provide a promising solution to combine living organisms with abiotic components,thus facilitating the construction of functional“living”*** natural materials,ELMs possess vitality and hold immense application potential in areas such as medicine,electronics,and construction,captivating increasing research attention *** an emerging branch of ELMs,structural ELMs aim to mimic living biological structural materials by achieving desired mechanical performance while maintaining important“living”*** we summarize the recent progress and provide our perspectives for this emerging research *** first summarize the superiority of structural ELMs by reviewing biological structural materials and biomimetic material design ***,we provide a systematic discussion on the definition and classifications of structural ELMs,their mechanical performance,and physiological ***,we summarize some critical challenges faced by structural ELMs and highlight directions of future *** hope this review article can provide a timely summary of the state of the art and relevant perspectives for future development of structural ELMs.

关键词： structural materials engineered living materials(ELMs) structural ELMs composites mechanical properties

The Method of Polynomial Particular Solutions for Solving Nonlinear Poisson-Type Equations

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Acta Mechanica Solida Sinica 2024年第1期37卷 155-165页

作者： Zhile jia Yanhua Cao Xiaoran Wu School of Sciences East China Jiaotong UniversityNanchang 330013China

In this paper,the method of polynomial particular solutions is used to solve nonlinear Poisson-type partial differential equations in one,two,and three *** condition number of the coefficient matrix is reduced through the implementation of multiple scale technique,ultimately yielding a stable numerical *** methodological process can be divided into two main parts:first,identifying the corresponding polynomial particular solutions for the linear differential operator terms in the governing equations,and second,employing these polynomial particular solutions as basis function to iteratively solve the remaining nonlinear terms within the governing ***,we investigate the potential improvement in numerical accuracy for equations with singularities in the analytical solution by shifting the computational domain a certain *** experiments are conducted to assess both the accuracy and stability of the proposed method.A comparison of the obtained results with those produced by other numerical methods demonstrates the accuracy,stability,and efficiency of the proposed method in handling nonlinear Poisson-type partial differential equations.

关键词： Nonlinear equation Singularity Polynomial particular solutions Poisson type

基于Matlab的打击气压对液气锤动态特性影响的研究

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机械强度 2017年第4期39卷 781-786页

作者：谢苗贾灿毛君徐畅辽宁工程技术大学机械工程学院阜新123000

打击气压是液压锤打击参量中影响动态特性的关键因素,为了提高设备的控制精度,以液气锤为研究对象,分别建立液气锤打击过程在未发生塑性变形阶段和塑性变形阶段的拉格朗日动力学模型,利用Matlab/Simulink数值计算方法研究液气锤打击过... 详细信息

打击气压是液压锤打击参量中影响动态特性的关键因素,为了提高设备的控制精度,以液气锤为研究对象,分别建立液气锤打击过程在未发生塑性变形阶段和塑性变形阶段的拉格朗日动力学模型,利用Matlab/Simulink数值计算方法研究液气锤打击过程的运动规律,深入分析打击气压变化对锻打系统动态特性的影响,为后期设备调试提供理论依据,以达到精确控制的目的。经现场试验研究表明,控制系统可以满足液气锤精确打击工艺的要求。

关键词：液气锤打击气压动态特性控制精度运动规律