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A Weakly-Supervised Crowd Density Estimation Method Based on Two-Stage linear Feature Calibration

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 965-981页

作者： Yong-Chao li rui-Sheng Jia Ying-xiang Hu Hong-Mei Sun the College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao 266590 the Faculty of Information Science and Engineering Ocean University of ChinaQingdao 266000China the College of Computer Science and Engineering Shandong University of Science and TechnologyQingdao 266590China the College of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210000China

In a crowd density estimation dataset,the annotation of crowd locations is an extremely laborious task,and they are not taken into the evaluation *** this paper,we aim to reduce the annotation cost of crowd datasets,and propose a crowd density estimation method based on weakly-supervised learning,in the absence of crowd position supervision information,which directly reduces the number of crowds by using the number of pedestrians in the image as the supervised *** this purpose,we design a new training method,which exploits the correlation between global and local image features by incremental learning to train the ***,we design a parent-child network(PC-Net)focusing on the global and local image respectively,and propose a linear feature calibration structure to train the PC-Net simultaneously,and the child network learns feature transfer factors and feature bias weights,and uses the transfer factors and bias weights to linearly feature calibrate the features extracted from the Parent network,to improve the convergence of the network by using local features hidden in the crowd *** addition,we use the pyramid vision transformer as the backbone of the PC-Net to extract crowd features at different levels,and design a global-local feature loss function(L2).We combine it with a crowd counting loss(LC)to enhance the sensitivity of the network to crowd features during the training process,which effectively improves the accuracy of crowd density *** experimental results show that the PC-Net significantly reduces the gap between fullysupervised and weakly-supervised crowd density estimation,and outperforms the comparison methods on five datasets of Shanghai Tech Part A,ShanghaiTech Part B,UCF_CC_50,UCF_QNRF and JHU-CROWD++.

关键词： Crowd density estimation linear feature calibration vision transformer weakly-supervision learning

In situ modification of heavy oil catalyzed by nanosized metal-organic framework at mild temperature and its mechanism

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Chinese Journal of Chemical Engineering 2024年第3期67卷 166-173页

作者： li Wang Ji-xiang Guo rui-Ying Xiong Chen-Hao Gao Xiao-Jun Zhang Dan Luo The Unconventional Oil and Gas Institute China University of Petroleum-BeijingBeijing 102200China Beijing Institute of Nanoenergy and Nanosystems Chinese Academy of SciencesBeijing 101400China

Two catalysts, nano-sized cobalt-metal-organic framework(Co-MOF) and nickel(Ni)-MOF, were successfully prepared by the modification method. Tetralin(C10H12) was used as the hydrogen donor for the catalytic cracking and hydrogenation modification study of the dehydrated crude oil from the Shengli Oilfield. The optimal reaction conditions were determined through orthogonal experiments, and the components of the crude oil and modified oil samples were analyzed. The results revealed that the nanoMOF catalysts were successfully prepared and exhibited high catalytic activity. They could catalyze the cracking of large molecules in heavy oil at mild temperatures(<300°C), leading to the decomposition of the hydrogen donor. When the mass fraction of the catalyst was 0.2%, the mass fraction of the hydrogen donor was 1%, and the reaction temperature was 280°C, the Ni-MOF showed the best catalytic viscosity reduction effect. It could reduce the viscosity of heavy oil at 50°C from 15761.9 m Pa.s to 1266.2 m Pa.s,with a viscosity reduction rate of 91.97%. The modification effect of Co-MOF was the next best, which could reduce the viscosity of heavy oil to 2500.1 m Pa.s with a viscosity reduction rate of 84.14%. Molecular dynamics simulations revealed a strong interaction force between the MOF surface and asphaltene molecules. In the process of heavy-oil catalytic hydrogenation, the nano-MOF catalyst exhibited high catalytic activity. On the one hand, the empty d orbitals outside the metal atoms in the catalyst could polarize the carbon atoms in the organic matter, accelerating the breaking of long chains. On the other hand, the metal atoms in the catalyst could bond with the carbon σ bonds, breaking the carbon-carbon bonds. This disrupted the structure of the recombined components in the crude oil, irreversibly reducing the viscosity of the heavy oil and improving its fluidity.

关键词： Nano-sized MOF Petroleum Viscosity reduction Catalyst Nanomaterials

Enhanced electrochemical performance of li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3) solid electrolyte by anion doping

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Nano Research 2024年第3期17卷 1465-1472页

作者： Jingrui Kang Xu Guo rui Gu Honglei Hao Yi Tang Jiahui Wang li Jin Hongfei li Xiaoyong Wei Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education&International Center for Dielectric ResearchSchool of Electronic and Information EngineeringXi’an Jiaotong UniversityXi’an 710049China School of Energy and Materials Shanghai Key Laboratory of Engineering Materials Application and EvaluationShanghai Polytechnic UniversityShanghai 201209China

Nowadays,the majority of the studies on the substitution are focused on cations(such as Y^(3+),Ti^(4+),P^(5+),etc.)in li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP),while there are few studies on the substitution of anion O^(2-).In this work,the modified LATP with a series of liCl(LATPClx,x=0.1,0.2,0.3,0.4)additives is prepared to enhance ionic *** successful introduction of Cl-makes the length of the c axis decrease from 20.822(2)to 20.792(1)Å,and the bulk conductivity of 2.13×10^(-3) S·cm^(-1) is achieved in LATPCl_(0.3).Moreover,the Al/Ti-O1/Cl1 and Al/Ti-O_(2)/Cl_(2) distance decrease,while the li1-O_(2)/Cl_(2) distance *** ions migrate more easily in the nanochannel of *** addition,the liCl additive increases the relative density and the grain boundary conductivity of LATPClx ***,a higher ionic conductivity of 2.12×10^(–4) S·cm^(-1) and a low activation energy of 0.30 eV are obtained in LATPCl_(0.3).Correspondingly,the symmetric cell exhibits a low overpotential of±50 mV for over 200 h in LATPCl_(0.3).The solid-state li|LATPCl_(0.3)|NCM811(NCM811=liNi0.8Co0.1Mn0.1O_(2))battery exhibits high initial capacity 185.1 mAh·g^(-1) with a capacity retention rate of 95.4%after 100 cycles at 0.5 *** result suggests that liCl additive is an effective strategy to promote electrochemical properties of LATP solid electrolyte and can be considered for reference to other inorganic solid electrolytes systems.

关键词： li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)solid electrolyte anion doping ionic conductivity cyclic performance

Demonstration of safety characteristics and effects on gut microbiota of Lactobacillus gasseri HMV18

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Food Science and Human Wellness 2024年第2期13卷 611-620页

作者： Xianxian Jia Miaomiao Jia xiang Gao xiang li Mengyuan Wang Shengqiang Du rui Huang Xiaotong li Jun Zhang Shujin li Chunling Ma Yan Zhang Bin Cong Department of Pathogen Biology Institute of basic MedicineHebei Medical UniversityShijiazhuang 050017China Research Unit of Digestive Tract Microecosystem Pharmacology and Toxicology Chinese Academy of Medical SciencesShijiazhuang 050017China Institute of Basic Medicine Hebei Medical UniversityShijiazhuang 050017China College of Forensic Medicine Hebei Key Laboratory of Forensic MedicineCollaborative Innovation Center of Forensic Medical Molecular IdentificationHebei Medical UniversityShijiazhuang 050017China Hebei Food Safety Key Laboratory Hebei Food Inspection and Research InstituteShijiazhuang 050227China

Human normal flora is a source of *** safety characteristics of a specific isolate determine its application in foods or *** food-borne-pathogen antagonist strain Lactobacillus gasseri HMV18 is one of the isolates from normal human *** this work,we assessed the in vitro pH tolerance,bile tolerance,biogenic amine production,mucin utilization,and safety of in vivo administration to mice to evaluate general health,organ-body weight index,organ histopathological change,whether *** HMV18 can colonize in the gut or modulate the gut microbiota after oral *** results suggest that *** HMV18 can tolerate pH 3 for 2 h,3%bile for 3 h,biogenic amine negative,mucin usage negative,does not encode verified toxins,and cause no visible change in mice's *** HMV18 might not colonize in mice's gut,but can significantly affect the structure of gut microbiota.A bibliographical survey suggested that there were as few as 8 opportunistic infection cases from 1984 to 2022 and that the possibility for *** to cause infection is relatively ***,this work provides a basis for the foods or drugs application of *** HMV18 and gives a map of experiments for the safety assessment of probiotics.

关键词： Probiotics Lactobacillus gasseri Safety assessment Gut microbiota

Development review and the prospect of oil shale in-situ catalysis conversion technology

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Petroleum Science 2024年第2期21卷 1385-1395页

作者： li Wang Chen-Hao Gao rui-Ying Xiong Xiao-Jun Zhang Ji-xiang Guo The Unconventional Oil and Gas Institute China University of Petroleum-BeijingBeijing102200China

As an unconventional resource, oil shale possesses abundant reserves and significant potential for industrial applications. The rational and efficient development of oil shale resources holds immense importance in reducing national energy demand. In-situ catalytic technology, characterized by its high efficiency, low pollution, and minimal energy consumption, represents a key direction for future oil shale development. This paper provides a comprehensive review of research progress in in-situ oil shale mining technology, oil shale pyrolysis catalysts, the pyrolysis mechanism of kerogen, and the compatibility of different heating processes and catalysts. Furthermore, the paper proposes future research directions and prospects for oil shale in-situ catalytic technology, including reservoir modification, highefficiency catalyst synthesis, injection processes, and high-efficiency heating technology. These insights serve as valuable technical references for the advancement of oil shale in-situ catalytic technology.

关键词： Oil shale In-situ catalytic technology Pyrolysis catalyst Kerogen pyrolysis mechanism

Theoretical analysis of the double-differential cross-sections of neutron,proton,deuteron,^(3)He,andαfor the p+^(6) li reaction

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Nuclear Science and Techniques 2024年第3期35卷 181-197页

作者： Fang-Lei Zou Xiao-Jun Sun Jing-Shang Zhang Hai-rui Guo Yin-Lu Han rui-rui Xu Xi Tao Ji-Min Wang Xiao-Dong Sun Yuan Tian Tao Ye Yong-li Xu Chun-Tian liang College of Physics Guangxi Normal University541004 GuilinChina Guangxi Key Laboratory of Nuclear Physics and Nuclear Technology 541004 GuilinChina China Institute of Atomic Energy P.O.Box 275(41)102413 BeijingChina Institute of Applied Physics and Computational Mathematics 10094 BeijingChina College of Physics and Electronic Shanxi Datong University037009 DatongChina School of Science Tianjin Chengjian University300384 TianjinChina

Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of light nucleus reaction(STLN)is developed to calculate the double-differential cross-sections of the outgoing neutron and light charged particles for the proton-induced^(6) li reaction.A significant difference is observed between the p+^(6) li and p+^(7) li reactions owing to the discrepancies in the energy-level structures of the *** reaction channels,including sequential and simultaneous emission processes,are analyzed in *** the double-differential cross-sections of the outgoing proton as an example,the influence of contaminations(such as^(1) H,^(7)li,^(12)C,and^(16)O)on the target is identified in terms of the kinetic energy of the first emitted *** optical potential parameters of the proton are obtained by fitting the elastic scattering differential *** calculated total double-differential cross-sections of the outgoing proton and deuteron at E_(p)=14 MeV agree well with the experimental data for different outgoing ***,the mixed double differential cross-sections of^(3) He andαare in good agreement with the *** agreement between the measured data and calculated results indicates that the two-body and three-body breakup reactions need to be considered,and the pre-equilibrium reaction mechanism dominates the reaction *** on the STLN model,a PLUNF code for the p+^(6) li reaction is developed to obtain an ENDF-6-formatted file of the double-differential cross-sections of the nucleon and light composite charged particles.

关键词： Statistical theory of light nucleus reaction p+^(6)li reaction light composite charged particle Double-differential cross-sections Two-body breakup Three-body breakup

Advanced cellulose-based materials toward stabilizing zinc anodes

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Science China Chemistry 2024年第5期67卷 1465-1484页

作者： Zhijiang li xiang Chen rui Zhang Taoyi Shen Jianchao Sun Zhongce Hu lin li Lanlan Yang Hou-Yong Yu College of Textile Science and Engineering(International Institute of Silk) Zhejiang Sci-Tech UniversityHangzhou 310018China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Donghua UniversityShanghai 201620China School of Environment and Material Engineering Yantai UniversityYantai 264005China Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China

Rechargeable aqueous zinc metal batteries(RAZMBs) have received extensive attention for large-scale energy storage systems due to the merits of Zn anodes, including moderate volumetric and gravimetric energy density, low redox potential, abundant reserve, low cost and impressive intrinsic safety. However, Zn anodes suffer from a series of adverse reactions(dendrite growth,hydrogen evolution, and surface passivation) resulting in low Coulombic efficiency, large polarization, and unsatisfied cycling performance, which inevitably hinder the wide application of RAZMBs. To address the above issues, cellulose-based materials are widely used for Zn anode protection because of their unique physical and chemical properties and other advantages such as biocompatibility, non-toxicity, degradability and easy extraction. In order to better understand the current progress in cellulosebased materials for the Zn anode protection, we have classified and summarized the relevant literatures. In this review, we summarize and elaborate the causes of poor reversibility for Zn anodes, including dendrite formation, hydrogen evolution, and surface passivation. Subsequently, the effective strategies(anode interfacial engineering, gel electrolyte optimization, and separator modification) of cellulose-based materials toward stabilizing Zn anodes are overviewed. In the end, the existing challenges and prospects of cellulose-based materials in Zn anode protection are summarized to shed light on future work.

关键词： Zn anode cellulose anode interfacial engineering gel electrolyte optimization separator modification

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APF-GAN:Exploring asymmetric pre-training and fine-tuning strategy for conditional generative adversarial network

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Computational Visual Media 2024年第1期10卷 187-192页

作者： Yuxuan li lingfeng Yang xiang li College of Computer Science Nankai UniversityTianjinChina School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjingChina

The use of generative adversarial network(GAN)-based models for the conditional generation of image semantic segmentation has shown promising results in recent ***,there are still some limitations,including limited diversity of image style,distortion of detailed texture,unbalanced color tone,and lengthy training *** address these issues,we propose an asymmetric pre-training and fine-tuning(APF)-GAN model.

关键词： tuning network asymmetric

Strong and tough chitin hydrogel constructed by dehydration and rehydration strategy

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Nano Research 2024年第9期17卷 8192-8199页

作者： rui-rui liu li-Bo Mao Shu-Hong Yu Division of Nanomaterials and Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials and ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China Institute of Innovative Materials Department of Materials Science and EngineeringDepartment of ChemistrySouthern University of Science and TechnologyShenzhen 518055China

As a renewable,biocompatible,biodegradable soft material,chitin hydrogels have better advantages in stability,antibacterial activity,antifouling,cost,immunogenicity,and so on than most polymer ***,compared with other widely used polymer hydrogels with high strength and toughness,the practical applications of chitin-based hydrogels have been limited by their weak mechanical properties,such as cartilage repair and meniscus ***,we present the design and fabrication of chitin hydrogels with excellent mechanical strength and toughness by a dehydration and rehydration *** sequential dehydration and rehydration processes,the crystalline domains in the chitin hydrogels can be properly *** optimized crystallinity,the elastic modulus of the chitin hydrogels exceeds all previously reported values,and the fracture toughness is even comparable to some synthetic polymer hydrogels,while maintaining a high-water-content of about 80 wt.%.At the same water content,the mechanical properties of the chitin hydrogels are positively correlated with the hydrogel crystallinity,which proves that the change of mechanical properties of hydrogels is not simply dependent on weight *** hydrogels can be further strengthened by incorporating other biopolymers that are intrinsically weak,which makes the hydrogels promising for applications in fields such as cartilage repair and meniscus ***,the hydrogels enable loading and release of water-soluble and poorly water-soluble *** highly extendable strengthening and toughening strategy of chitin and chitin-based biopolymer hydrogels paves the way for their widely applications.

关键词： chitin hydrogel crystallinity rehydration chemical transformation strong and tough