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Real-time K-TIG welding penetration prediction on embedded system using a segmentation-LSTM model

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Advances in Manufacturing 2023年第3期11卷 444-461页

作者： yong-hua shi Zi-Shun Wang Xi-Yin Chen Yan-Xin Cui Tao Xu Jin-Yi Wang School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510006People's Republicof China

Keyhole tungsten inert gas(K-TIG)welding is capable of realizing single-sided welding and double-sided forming and has been widely used in medium and thick plate *** order to improve the accuracy of automatic weld identification and weld penetration prediction of robot in the process of large workpiece welding,a two-stage model is proposed in this paper,which can monitor the K-TIG welding penetration state in real time on the embedded system,called segmentation-LSTM *** proposed system extracts 9 weld pool geometric features with segmentation network,and then extracts the weld gap using a traditional *** these 10-dimensional features are input into the LSTM model to predict the penetration state,including under penetration,partial penetration,good penetration and over *** recognition accuracy of the proposed system can reach 95.2%.In this system,to solve the difficulty of labeling data and lack of segmentation accuracy,an improved LabelMe capable of live-wire annotation tool and a novel loss function were proposed,*** latter was also called focal dice loss,which enabled the network to achieve a performance of 0.933 mloU on the testing ***,an improved slimming strategy compresses the network,making the segmentation network achieve real-time on the embedded system(RK3399pro).

关键词： Keyhole tungsten inert gas(K-TIG)welding Penetration state prediction Segmentation-LSTM model Embedded system Focal dice loss Improved LabelMe

Mirizzi syndrome:Problems and strategies

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 234-240页

作者： Jun Wu Shuang-yong Cai Xu-Liang Chen Zhi-Tao Chen Shao-hua shi Department of Hepatobiliary and Pancreatic Surgery People’s Hospital of Jiulongpo DistrictChongqing 400050China Department of Hepatobiliary and Pancreatic Surgery Shulan(Hangzhou)Hospital Affiliated to Zhejiang Shuren University Shulan International Medical CollegeHangzhou 310003China

Mirizzi syndrome is a serious complication of gallstone *** is caused by the impacted stones in the gallbladder neck or cystic *** of the features of Mirizzi syndrome is severe inflammation or dense fibrosis at the Calot’s *** our clinical practice,bile duct,branches of right hepatic artery and right portal vein clinging to gallbladder infundibulum are often observed due to gallbladder infundibulum adhered to right hepatic *** intraoperative damage of branches of right hepatic artery occurs more easily than that of bile duct,all of which are hidden pitfalls for *** resonance cholangiopancreatography(MRCP)and endoscopic retrograde cholangiopancreatography(ERCP)are the preferable tools for the diagnosis of Mirizzi *** cholecystectomy in Mirizzi syndrome is easy to damage branches of right hepatic artery and bile duct due to gallbladder infundibulum adhered to right hepatic *** cholecystectomy is an easy,safe and definitive approach to Mirizzi *** combined with the application of ERCP,a laparoscopic management of Mirizzi syndrome by well-trained surgeons is feasible and *** objective of this review was to highlight its existing problems:(1)low preoperative diagnostic rate,(2)easy to damage bile duct and branches of right hepatic artery,and(3)high concomitant gallbladder ***,the review aimed to discuss the possible therapeutic strategies:(1)to enhance its preoperative recognition by imaging findings,and(2)to avoid potential pitfalls during surgery.

关键词： Mirizzi syndrome Bile duct injury Artery injury Surgical treatment Subtotal cholecystectomy

Regulation of the quantum barrier and carrier transport toward high-efficiency quasi-2D Dion-Jacobson tin perovskite solar cells

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Journal of Energy Chemistry 2024年第8期95卷 200-207,I0005页

作者： huanhuan Yao Chang shi Tai Wu Shurong Wang Mingyu Yin Liming Ding yong hua Feng Hao School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China Yunnan Key Laboratory for Micro/Nano Materials&Technology School of Materials and EnergyYunnan UniversityKunming 650091YunnanChina Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190China

Quasi-2D Dion-Jacobson(DJ)tin halide perovskite has attracted much attention due to its elimination of Van der Waals gap and enhanced environmental ***,the bulky organic spacers usually form a natural quantum well structure,which brings a large quantum barrier and poor film quality,further limiting the carrier transport and device ***,we designed three organic spacers with different chain lengths(ethylenediamine(EDA),1,3-propanediamine(PDA),and 1,4-butanediamine(BDA))to investigate the quantum barrier *** and experimental characterizations indicate that EDA with short chain can reduce the lattice distortion and dielectric confinement effect,which is beneficial to the effective dissociation of excitons and the inhibition of trap-free non-radiative *** addition,EDA cation shows strong interaction with the inorganic octahedron,realizing large aggregates in precursor solution and high-quality films with improved structural ***,femtosecond transient absorption proves that EDA cations can also weaken the formation of small n-phases with large quantum barrier to achieve effective carrier transport between different ***,the quasi-2D DJ(EDA)FA_(9)Sn_(10)I_(31)solar cells achieves a 7.07%power conversion efficiency with good environment ***,this work sheds light on the regulation of the quantum barrier and carrier transport through the chain length of organic spacer for qua si-2D DJ lead-free perovskites.

关键词： Chain lengths Organic spacers Quantum well Carrier transport Lattice distortion

Novel Fault Diagnosis Scheme for HVDC System via ESO

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高电压技术 2007年第11期33卷 88-93页

作者： YAN Bing-yong TIAN Zuo-hua shi Song-jiao Department of Automation Shanghai Jiao Tong University Shanghai 200240 China

A novel fault detection and identification(FDI)scheme for HVDC(High Voltage Direct Current Transmission)system was *** was based on the unique active disturbance rejection concept,where the HVDC system faults were estimated using an extended states observer(ESO).Firstly,the mathematical model of HVDC system was constructed,where the system states and disturbance were treated as an extended *** augment HVDC system was established by using the extended state in rectify side and converter side,***,a fault diagnosis filter was established to diagnose the HVDC system faults via the ESO *** evolution of the extended state in the augment HVDC system can reflect the actual system faults and disturbances,which can be used for the fault diagnosis purpose.A novel feature of this approach is that it can simultaneously detect and identify the shape and magnitude of the HVDC faults and ***,different kinds of HVDC faults were simulated to illustrate the feasibility and effectiveness of the proposed ESO based FDI *** with the neural network based or support vector machine based FDI approach,the ESO based FDI scheme can reduce the fault detection time dramatically and track the actual system fault ***'s more important,it needs not do complex online calculations and the training of neural network so that it can be applied into practice.

关键词：高压直流输电系统故障检验与识别故障诊断分支状态观测器

Concise extraction and characterization of the pore-throat network in unconventional hydrocarbon reservoirs: A new perspective

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Petroleum Science 2024年第3期21卷 1474-1487页

作者： Shu-Heng Du yong-Min shi State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing100190China School of Engineering Science University of Chinese Academy of SciencesBeijing100049China School of Earth and Space Sciences Peking UniversityBeijing100871China

In this study,a new image-based method for the extraction and characterization of pore-throat network for unconventional hydrocarbon storage and exploitation is proposed.“Pore-throat solidity”,which is analogous to particle solidity,and a new method for automatic identification of pores and throats in tight sandstone oil reservoirs are ***,the“pore-throat combination”and“pure pore”are defined and distinguished by drawing the cumulative probability curve of the pore-throat solidity and by selecting an appropriate cutoff *** the discrete grid set is recognized as a pore-throat combination,Legendre ellipse fitting and minimum Feret diameter are *** the pore and throat grid sets are identified as pure pores,the pore diameter can be directly *** the new method,the analytical results for the physical parameters and pore radius agree well with most prior *** results comparing the maximum ball and the new model could also prove the accuracy of the latter's in micro and nano *** new model provides a more practical theoretical basis and a new calculation method for the rapid and accurate evaluation of the complex processes of oil migration.

关键词： Hydrocarbon exploitation Pore Throat Porous media Identification

Irisin-loaded electrospun core-shell nanofibers as calvarial periosteum accelerate vascularized bone regeneration by activating the mitochondrial SIRT3 pathway

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Regenerative Biomaterials 2024年第1期3卷 44-57页

作者： Xi hua Mingzhuang Hou Lei Deng Nanning Lv yong Xu Xuesong Zhu Huilin Yang Qin shi Hao Liu Fan He Department of Orthopaedics The First Affiliated Hospital of Soochow UniversitySoochow UniversitySuzhou 215006China Orthopaedic Institute Suzhou Medical CollegeSoochow UniversitySuzhou 215000China Department of Orthopedics Suzhou Wuzhong People’s HospitalSuzhouJiangsu Province 215128China Department of Orthopedic Surgery Lianyungang Clinical College of Xuzhou Medical UniversityLianyungang 222003China

The scarcity of native periosteum poses a significant clinical barrier in the repair of critical-sized bone *** challenge of enhancing regenerative potential in bone healing is further compounded by oxidative stress at the fracture ***,the introduction of artificial periosteum has demonstrated its ability to promote bone regeneration through the provision of appropriate mechanical support and controlled release of proosteogenic *** this study,a poly(L-lactic acid)(PLLA)/hyaluronic acid(HA)-based nanofibrous membrane was fabricated using the coaxial electrospinning *** incorporation of irisin into the core-shell structure of PLLA/HA nanofibers(PLLA/HA@Irisin)achieved its sustained *** vitro experiments demonstrated that the PLLA/HA@Irisin membranes exhibited favorable *** osteogenic differentiation of bone marrow mesenchymal stem cells(BMMSCs)was improved by PLLA/HA@Irisin,as evidenced by a significant increase in alkaline phosphatase activity and matrix ***,PLLA/HA@Irisin significantly enhanced the mitochondrial function of BMMSCs via the activation of the sirtuin 3 antioxidant *** assess the therapeutic effectiveness,PLLA/HA@Irisin membranes were implanted in situ into critical-sized calvarial defects in *** results at 4 and 8 weeks post-surgery indicated that the implantation of PLLA/HA@Irisin exhibited superior efficacy in promoting vascularized bone formation,as demonstrated by the enhancement of bone matrix synthesis and the development of new blood *** results of our study indicate that the electrospun PLLA/HA@Irisin nanofibers possess characteristics of a biomimetic periosteum,showing potential for effectively treating critical-sized bone defects by improving the mitochondrial function and maintaining redox homeostasis of BMMSCs.

关键词： periosteum irisin mitochondrial function critical-sized bone defect redox homeostasis

Aboveground biomass stocks of species-rich natural forests in southern China are influenced by stand structural attributes,species richness and precipitation

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Plant Diversity 2024年第4期46卷 530-536页

作者： Wen-Hao Zeng shi-Dan Zhu Ying-hua Luo Wei shi yong-Qiang Wang Kun-Fang Cao State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources College of ForestryGuangxi UniversityNanning 530004China Guangxi Key Laboratory of Forest Ecology and Conservation College of ForestryGuangxi UniversityNanning 530004China Key Laboratory of National Forestry and Grassland Administration on Biodiversity Conservation in Karst Mountainous Areas of Southwestern China School of Life SciencesGuizhou Normal UniversityHuaxi College TownGui'an DistrictGuiyang 550025China

Forests,the largest terrestrial carbon sinks,play an important role in carbon sequestration and climate change *** forest attributes and environmental factors have been shown to impact aboveground biomass,their influence on biomass stocks in species-rich forests in southern China,a biodiversity hotspot,has rarely been *** this study,we characterized the effects of environmental factors,forest structure,and species diversity on aboveground biomass stocks of 30 plots(1 ha each) in natural forests located within seven nature reserves distributed across subtropical and marginal tropical zones in Guangxi,*** results indicate that forest aboveground biomass stocks in this region are lower than those in mature tropical and subtropical forests in other ***,we found that aboveground biomass was positively correlated with stand age,mean annual precipitation,elevation,structural attributes and species richness,although not with species *** we compared stands with the same basal area,we found that aboveground biomass stock was higher in communities with a higher coefficient of variation of diameter at breast *** findings highlight the importance of maintaining forest structural diversity and species richness to promote aboveground biomass accumulation and reveal the potential impacts of precipitation changes resulting from climate warming on the ecosystem services of subtropical and northern tropical forests in ***,many natural forests in southern China are not fully ***,their continued growth will increase their carbon storage over time.

关键词： Subtropical forest Marginal tropical forest Aboveground biomass Species diversity Forest structural attribute Environment factor

Donor-acceptor covalent organic frameworks-confined ultrafine bimetallic Pt-based nanoclusters for enhanced photocatalytic H_(2)generation

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Nano Research 2024年第7期17卷 5835-5844页

作者： Yu Liu Yawen shi hua Wang Shengbo Zhang Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Key Laboratory for Green Chemical Technology of the Ministry of EducationSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China School of Environmental Science and Engineering Tianjin Key Laboratory of Biomass/Wastes UtilizationTianjin UniversityTianjin 300350China

Photocatalytic hydrogen generation from hydrogen storage media is an effective and promising approach for the green hydrogen industry as well as for achieving carbon neutrality ***,the lower photocatalytic efficiency due to the limited light trapping capacity,low electron transfer rate,and severe aggregation of nanoparticles caused by high surface energy seriously restricts their practical ***,we constructed a series of donor–acceptor(D–A)type covalent organic frameworks to confine ultrafine bimetallic Pt-based nanoclusters for photocatalytic hydrogen generation from ammonia borane(AB)*** visible light irradiation at 20℃,PtCo_(2)@covalent organic framework(COF)showed the highest photocatalytic activity with a turnover frequency(TOF)of 486 min−*** and density functional theory(DFT)calculations reveal that the high catalytic activity is mainly attributed to the strong electronic interactions between D–A type COF and ultrafine PtCo_(2)***,the D–A type COF can significantly enhance the light-trapping ability by fine-tuning the electron-acceptor type in the framework,and accelerate the photogenerated electron transfer from D–A type COF to PtCo_(2)nanocluster,which promotes the adsorption and activation of H_(2)O and AB molecules and accelerates hydrogen ***,PtCo_(2)@COF also exhibited ultra-high durability due to the significantly enhanced resistance to nanocluster aggregation caused by the nanopore confinement effect of D–A type *** believe that this work will provide a theoretical guide for the rational design of efficient D–A COFbased catalysts for photocatalysis.

关键词： light trapping electron transfer donor-acceptor covalent organic frameworks(D-A COFs) bimetallic nanoclusters photocatalysis

Emergence of SARS and COVID-19 and preparedness for the next emerging disease X

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Frontiers of Medicine 2024年第1期18卷 1-18页

作者： Ben Hu hua Guo Haorui Si Zhengli shi CAS Key Laboratory of Special Pathogens and Biosafety Wuhan Institute of VirologyChinese Academy of SciencesWuhan430071China University of Chinese Academy of Sciences Beijing100049China

Severe acute respiratory syndrome(SARS)and Coronavirus disease 2019(COVID-19)are two human Coronavirus diseases emerging in this century,posing tremendous threats to public health and causing great loss to lives and *** this review,we retrospect the studies tracing the molecular evolution of SARS-CoV,and we sort out current research findings about the potential ancestor of *** knowledge about SARS-CoV-2-like viruses found in wildlife,the animal susceptibility to SARS-CoV-2,as well as the interspecies transmission risk of SARS-related coronaviruses(SARSr-CoVs)are gathered ***,we discuss the strategies of how to be prepared against future outbreaks of emerging or re-emerging coronaviruses.

关键词： SARS COVID-19 coronavirus