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2D and 3D Palmprint and Palm Vein Recognition Based on Neural Architecture Search

International Journal of Automation and computing 2021年第3期18卷 377-409页

作者： Wei jia Wei Xia Yang Zhao Hai Min Yan-Xiang Chen School of Computer Science and Information Engineering Hefei University of TechnologyHefei 230009China Anhui Province Key Laboratory of Industry Safety and Emergency Technology Hefei 230009China

Palmprint recognition and palm vein recognition are two emerging biometrics *** the past two decades,many traditional methods have been proposed for palmprint recognition and palm vein recognition and have achieved impressive *** recent years,in the field of artificial intelligence,deep learning has gradually become the mainstream recognition technology because of its excellent recognition *** researchers have tried to use convolutional neural networks(CNNs)for palmprint recognition and palm vein ***,the architectures of these CNNs have mostly been developed manually by human experts,which is a time-consuming and error-prone *** order to overcome some shortcomings of manually designed CNN,neural architecture search(NAS)technology has become an important research direction of deep *** significance of NAS is to solve the deep learning model's parameter adjustment problem,which is a cross-study combining optimization and machine *** technology represents the future development direction of deep ***,up to now,NAS technology has not been well studied for palmprint recognition and palm vein *** this paper,in order to investigate the problem of NAS-based 2D and 3D palmprint recognition and palm vein recognition in-depth,we conduct a performance evaluation of twenty representative NAS methods on five 2D palmprint databases,two palm vein databases,and one 3D palmprint *** results show that some NAS methods can achieve promising recognition ***,among different evaluated NAS methods,Proxyless NAS achieves the best recognition performance.

关键词： Performance evaluation neural architecture search biometrics palmprint palm vein deep learning

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UV-triggered Polymerization of Polyelectrolyte Composite Coating with Pore Formation and Lubricant Infusion

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Chinese Journal of Polymer Science 2023年第3期41卷 365-372,I0004,I0006页

作者： jia-Qi Hu Wei-Pin Huang Jing Wang Ke-Feng Ren jian Ji MOE Key Laboratory of Macromolecular Synthesis and Functionalization International Research Center for X PolymersDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

Porous coatings with the features of muti-interfaces and high specific surface area have emerged as an excellent material platform for the manipulation of porous ***-by-layer(Lb L)assembly technique has been widely used in preparing porous polyelectrolyte ***,the efficient construction of stable film from the Lb L technique is still a ***,we reported a new solution to construct a stabilized polyelectrolyte coating with porous *** by the mechanical reinforcement of double-network hydrogel,we constructed the poly(ethylenimine)(PEI)/poly(acrylic acid)(PAA)coating by in situ photopolymerization of acrylic acid in the PEI network instead of assembling PEI and *** with the Lb L films,the in situ polymerized coating kept higher stability after 30 iterations of *** structures could also be constructed after acid treatment,which was utilized to load lubricant to enhance the lubricating property of the *** work provides a new method for the construction of dynamic and stable polyelectrolyte coatings,expediting more development of practical applications.

关键词： Porous coating Polyelectrolyte coating Dip-coating UV-triggered polymerization Stability

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Optimized parameters of downhole all-metal PDM based on genetic algorithm

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Petroleum Science 2024年第4期21卷 2663-2676页

作者： jia-Xing Lu Ling-Rong Kong Yu Wang Chao Feng Yu-Lin Gao China University of Geosciences(Beijing) Beijing100083China Key Laboratory on Deep Geo-Drilling Technology of Ministry of Natural Resources Beijing100083China

Currently,deep drilling operates under extreme conditions of high temperature and high pressure,demanding more from subterranean power *** all-metal positive displacement motor,known for its robust performance,is a critical choice for such *** dimensions of the PDM are crucial for its performance *** enhance this,optimization of the motor's profile using a genetic algorithm has been *** design process begins with the computation of the initial stator and rotor curves based on the equations for a screw *** curves are then refined using the least squares method for a precise *** this,the PDM's mathematical model is optimized,and motor friction is *** genetic algorithm process involves encoding variations and managing crossovers to optimize objective functions,including the isometric radius coefficient,eccentricity distance parameter,overflow area,and maximum slip *** optimization yields the ideal profile parameters that enhance the motor's *** analyses of the initial and optimized output characteristics were conducted,focusing on the effects of the isometric radius coefficient and overflow area on the motor's *** indicate that the optimized motor's overflow area increased by 6.9%,while its rotational speed reduced by 6.58%.The torque,as tested by Infocus,saw substantial improvements of38.8%.This optimization provides a theoretical foundation for improving the output characteristics of allmetal PDMs and supports the ongoing development and research of PDM technology.

关键词： Positive displacement motor Genetic algorithm Profile optimization Matlab programming Overflow area

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Insight into the Role of Isolated Gold Atoms-Ceria Conjunction in Catalyzing the Water-Gas Shift Reaction

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Chinese Journal of Chemistry 2024年第6期42卷 636-644页

作者： Xin-Pu Fu Hui-Zhao Wei-Wei Wang Chun-jiang jia Key Laboratory for Colloid and Interface Chemistry Key Laboratory of Special Aggregated MaterialsSchool of Chemistry and Chemical EngineeringShandong UniversityJinanShandong250100 China

As the promising catalysts for the water-gas shift(WGS)reaction,the activity of Au-CeO_(2) composites is susceptible to the aggregation size and electronic state of Au *** reports were extensively focused on the discrepancy between nonmetallic Au and metallic Au nanoparticles,whereas the understanding of the authentic role of the isolated Au atoms was ***,we investigated the catalytic behavior and structural information over two types of Au/CeO_(2) catalysts,in which the predominant conjunctions were isolated Au1-CeO_(2) and Aun-CeO_(2),*** on comprehensive characterizations,particularly by in-situ Raman and in-situ DRIFTS,we found that the isolated Au atoms were responsible for enhancing the reducibility of the CeO_(2) *** CO adsorption ability on the isolated Au sites was significantly inferior to clustered Au atoms,especially at relatively high temperatures(>200°C).As a result,the boosted O vacancy on the isolated Au1-CeO_(2) conjunctions could improve the H2O activation ability for the Au-CeO_(2) catalysts and demonstrate a comparable activity to the clustered Aun-CeO_(2) *** work might deepen understanding of the catalytic function for the isolated Au1 site within Au/CeO_(2) systems while catalyzing the WGS reaction.

关键词： Isolated Au atoms Ceria-based catalysts Water-gas shift reaction Defect Adsorption

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Polymer Translocation

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Chinese Journal of Polymer Science 2023年第5期41卷 683-698,I0007页

作者： Lu-Wei Lu Zhen-Hua Wang An-Chang Shi Yu-Yuan Lu Li-jia An State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China Department of Physics and Astronomy McMaster UniversityHamiltonOntario L8S4M1Canada

The translocation of a polymer through a pore that is much smaller than its size is a fundamental and actively researched topic in polymer *** understanding of the principles governing polymer translocation provides important guidance for various practical applications,such as the separation and purification of polymers,nanopore-based single-molecule deoxyribonucleic acid/ribonucleic acid(DNA/RNA)sequencing,transmembrane transport of DNA or RNA,and infection of bacterial cells by *** past several decades have seen great progresses on the study of polymer *** we present an overview of theoretical,experimental,and simulational stduies on polymer translocation,focusing on the roles played by several important factors,including initial polymer conformations,external fields,polymer topology and architectures,and confinement *** highlight the physical mechanisms of different types of polymer translocations,and the main controversies about the basic rules of translocation *** compare and contrast the behaviors of force-induced versus flow-induced translocations and the effects of unknotted versus knotted ***,we mention several opportunities and challenges in the study of polymer translocation.

关键词： Polymer translocation Knotted polymers Translocation time Critical flux

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Association between CYP24A1 polymorphisms and the risk of colonic polyps and colon cancer in a Chinese population

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World Journal of Gastroenterology 2017年第28期23卷 5179-5186页

作者： Xue-Qi Chen jia-Yu Mao Wen-Bin Li jian Li Hong Yang jia-Ming Qian Jing-Nan Li Department of Gastroenterology Peking Union Medical College Hospital Department of General Surgery Henan Cancer Hospital

AIM To determine the pathogenesis and potential single nucleotide polymorphisms(SNPs) as screening sites for colonic polyps,colon cancer and ulcerative colitis,and to analyze the possible association between these genetic polymorphisms and the three diseases. METHODS We evaluated genetic polymorphisms in 144 newly diagnosed colonic polyp patients,96 colon cancer patients and 44 ulcerative colitis patients. The four SNPs genotyped were rs4809957,rs6068816,rs6091822 and rs8124792. The control group consisted of 504 East Asians enrolled in the 1000 Genomes Project. Correlations between CYP24A1 SNPs and the diseases were analyzed by Fisher's exact probability *** CYP24A1 polymorphisms rs4809957 A/G and rs6068816 C/T showed a statistically significant association with risk of the three diseases,when both the genotypes and allele frequencies were considered. With regard to rs6091822 G/T,all three diseases were related to risk allele carriers(GT + TT) vs wild-type(GG),but the associations between the allele frequencies and the diseases were not significant. The risk of colonic polyps and colon cancer was related to the allele frequencies of rs8124792 G/A,and this association remained for genotype frequencies of this SNP. CONCLUSION Four SNPs are related to the risk of colonic polyps and colon cancer. G allele in rs6091822 G/T may play an anti-cancer role only if it is homozygous. The A allele,which is a minor component of rs8124792,may be indicated in the diagnosis of colonic polyps or colon cancer rather than ulcerative colitis.

关键词： CYP24A1 Single nucleotide polymorphisms Colonic polyps Colon cancer

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Evolution of the Lagrangian drift and vortex added-mass of a growing vortex ring

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Journal of Hydrodynamics 2021年第4期33卷 725-735页

作者： Shu-jia Lin Yang Xiang Zhuo-qi Li Fu-xin Wang Hong Liu School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai200240China

The vortex-based propulsive systems’ enhanced performance greatly contributes to the vortex added-mass effect, which was initially developed to explain the added drag when a solid body accelerates in fluids. However, the solution of the instantaneous vortex added-mass coefficient is still remaining a question because vortices always do not have a stable geometric shape like solid bodies. In this paper, the formation of a canonical vortex ring is performed to investigate the nature of vortex added-mass and explore a solution for estimating the vortex added-mass coefficient. The vortex ring is generated by a piston-cylinder apparatus, and the time-dependent flow fields are recorded by particle image velocimetry technique. The ridges of finite-time Lyapunov exponent are applied to identify the Lagrangian boundary of the vortex ring. It is found that a part of the ambient fluids is entrained by the vortex ring when it propagates downstream, resulting in the growth of the vortex ring. Besides, a significant drift of the ambient fluid is observed to bypass the Lagrangian boundary of the vortex ring and reveals the nature of the vortex added-mass. Thus, the added-mass coefficient of the vortex is redefined as the ratio of the volume of the Lagrangian drift fluids in finite time interval step to the vortex volume at that instant. By referring to McPhaden’s method to estimate the added-mass of a solid body, a method based on the multiple material lines with relative-timestep is developed to estimate the volume of Lagrangian drift fluids induced by the vortex added-mass. Then, an empirical criterion for determining the material line number and the finite time interval step is suggested for the vortex ring flow, and the eventual vortex added-mass coefficient calculated by the volume of Lagrangian drift fluids is found to well agree with the results of Brennen. Moreover, the method based on multiple material lines for calculating Lagrangian drift fluids’ volume suggests a poten

关键词： Added-mass Lagrangian coherent structure(LCS) finite-time Lyapunov exponent(FTLE)

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Si/TiO_(2) carbon fiber core encapsulated in hierarchical multiple MXene@Co-MoS_(2) shells for constructing a free-standing anode of lithium storage

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Rare Metals 2024年第9期43卷 4222-4233页

作者： Xian-ping Du Ying Huang jia-ming Wang Zhen-he Feng Xu Sun MOE Key Laboratory of Material Physics and Chemistry Under Extraordinary Conditions School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Shanghai Institute of Space Power-Sources Shanghai 200245China Ningbo Institute of Northwestern Polytechnical University Ningbo 315103China

Silicon-based(Si-based) materials offer more possibilities for generating new portable electronic devices due to their high specific capacities. However, their inferior electrical conductivity and volume expansion during cycling seriously limit their development. The optimum solution is to select specific materials to establish an exceptionally conductive and volume buffer structure,which can assist Si materials in developing their excellent lithium storage properties. In this study, Si particles were confined in TiO_(2)carbon fibers(TiO_(2)CFs) via electrospinning, after which they were encapsulated with MXene and Co-MoS_(2)(CMS) nanosheets to fabricate hierarchical ST-2@MXene@CMS films. TiO_(2)CF, MXene and CMS were employed to establish a coherent conductive network with one-, two-and three-dimensional electronic pathways to permit the unimpeded flow of electrons inside the electrode material. TiO_(2)CF, MXene and CMS acted precisely as multilayered buffers to ameliorate the volume change of Si particles during cycling. In addition, the CMS nanosheets were involved in lithium storage, contributing to the final electrochemical performance. Ultimately, the ST-2@MXene@CMS films served as free-standing electrodes, avoiding the impact of inactive interfaces on the electrochemical performance and fulfilling the lightweight requirement for new energy storage devices.

关键词： Si particles MXene Co-MoS_(2)nanosheets Hierarchical structure Lithium-ion batteries

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How water molecules occupying the active site of a single-atom catalyst affect the electrochemical reduction of carbon dioxide

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Nano Research 2023年第7期16卷 9091-9098页

作者： jia Zhao Di Liu Fenfei Wei Weng Fai Ip Hui Pan Sen Lin State Key Laboratory of Photocatalysis on Energy and Environment College of ChemistryFuzhou UniversityFuzhou 350002China Institute of Applied Physics and Materials Engineering University of MacaoTaipa 999078MacaoChina Department of Physics and Chemistry Faculty of Science and TechnologyUniversity of MacaoTaipa 999078MacaoChina

In single-atom catalysts(SACs),the single atoms are often exposed as protrusions above the *** solvent molecules in the electrocatalytic environment can interact or even bind to these coordination-unsaturated single atoms and thus influence the reaction process,but this has not been studied in *** this work,we systematically investigate the thermodynamics of CO_(2)reduction reaction(CO_(2)RR)to CO over MoS_(2)-supported single metal atom catalysts(TM@MoS_(2),TM=transition metal)under vacuum and explicit solvent environments using density functional *** addition,the ab initio molecular dynamics results show that explicit H_(2)O molecules can coordinate to the TM site and undergo competitive adsorption with the CO_(2)RR intermediates,which significantly affects the energy and conformation of the CO_(2)RR *** structure analysis reveals that the occupying H_(2)O molecules change the electronic state of single atom and further influence the adsorption strength of different CO_(2)RR *** work shows that water molecules can not only act as ligands to influence the electronic state of TM,but also affect the energy and conformation of CO_(2)RR intermediates,which highlights the important role of occupying H_(2)O molecules at the single-atom sites in CO_(2)RR and provides useful insights for the design of SACs for efficient CO_(2)RR.

关键词： electrocatalytic CO_(2)reduction solvent effect single-atom catalysis density functional theory ab initio molecular dynamics

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An Intrusion Detection Method Based on Hierarchical Hidden Markov Models

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Wuhan University Journal of Natural Sciences 2007年第1期12卷 135-138页

作者： jia Chunfu YANG Feng College of Information Science and Technology Universityof Science and Technology of China Hefei 230026 Anhui China College of Information Technology and Science NankaiUniversity Tianjin 300071 China

This paper presents an anomaly detection approach to detect intrusions into computer systems. In this approach, a hierarchical hidden Markov model （HHMM） is used to represent a temporal profile of normal behavior in a computer system. The HHMM of the norm profile is learned from historic data of the system＇s normal behavior. The observed behavior of the system is analyzed to infer the probability that the HHMM of the norm profile supports the observed behavior. A low probability of support indicates an anomalous behavior that may result from intrusive activities. The model was implemented and tested on the UNIX system call sequences collected by the University of New Mexico group. The testing results showed that the model can clearly identify the anomaly activities and has a better performance than hidden Markov model.

关键词： intrusion detection hierarchical hidden Markov model anomaly detection

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