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Joined AZ31B Magnesium Alloys with Ag Interlayer by Ultrasonic-Induced Transient Liquid Phase Bonding in Air

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1177-1185页

作者： qian Wang peng yu Haoran Lin Chongzhi Guo Xiaoqiang Hu Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341119China School of Rare Earths University of Science and Technology of ChinaHefei230026China Shenyang 7D New Materials Equipment Co.LTD. Shenyang110076China Shenyang National Laboratory of Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

AZ31B magnesium alloys are commonly used in lightweight structures of automobile and aerospace *** this work,the ultrasonic-induced transient liquid phase bonding technique is deployed to joint AZ31B magnesium alloys at 490℃ with Ag interlayer in the *** effect of ultrasonic vibration on microstructure and mechanical properties of welding seam is *** vibration duration increases,the width of the welding seam increases firstly and then *** the ultrasound vibration sustained for one second,the eutectic reaction occurred in the contacting interface between Ag interlayer and the base metal AZ31B,resulting in formation of liquid phase and metallurgical *** the ultrasound vibration sustained for seven second,the width of the welding seam increased to a maximum of about 303.1μm and the average shear bond strength of the welding joint attained the peak value of about 66.87 *** the ultrasound vibration sustained over seven seconds,the liquid phase is gradually squeezed out and the width of the welding seam decreases.α-Mg and AgMg_(3) can be observed in the welding *** analysis shows thatα-Mg has a certain strengthening *** whole process of appearance,growth and integration ofα-Mg is analyzed.

关键词： Ultrasonic bonding Magnesium alloy Silver Microstructure Intermetallic compound

Correlating learning and memory improvements to long-term potentiation in patients with brain injury

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Neural Regeneration Research 2008年第2期3卷 172-176页

作者： Xingfu peng qian yu Department of Rehabilitation Medicine Affiliated Hospital of Luzhou Medical College Luzhou 646000 Sichuan Province China

BACKGROUND： Brain injury patients often exhibit learning and memory functional deficits. Long-term potentiation （LTP） is a representative index for studying learning and memory cellular models; the LTP index correlates to neural plasticity. OBJECTIVE： This study was designed to investigate correlations of learning and memory functions to LTP in brain injury patients, and to summarize the research advancements in mechanisms underlying brain functional improvements after rehabilitation intervention. RETRIEVAL STRATEGY： Using the terms ＂brain injuries, rehabilitation, learning and memory, long-term potentiation＂, manuscripts that were published from 2000-2007 were retrieved from the PubMed database. At the same time, manuscripts published from 2000-2007 were also retrieved from the Database of Chinese Scientific and Technical Periodicals with the same terms in the Chinese language. A total of 64 manuscripts were obtained and primarily screened. Inclusion criteria： studies on learning and memory, as well as LTP in brain injury patients, and studies focused on the effects of rehabilitation intervention on the two indices; studies that were recently published or in high-impact journals. Exclusion criteria： repetitive studies. LITERATURE EVALUATION： The included manuscripts primarily focused on correlations between learning and memory and LTP, the effects of brain injury on learning and memory, as well as LTP, and the effects of rehabilitation intervention on learning and memory after brain injury. The included 39 manuscripts were clinical, basic experimental, or review studies. DATA SYNTHESIS： Learning and memory closely correlates to LTP. The neurobiological basis of learning and memory is central nervous system plasticity, which involves neural networks, neural circuits, and synaptic connections, in particular, synaptic plasticity. LTP is considered to be an ideal model for studying synaptic plasticity, and it is also a classic model for studying neural plasticity

关键词： learning and memory brain injury long-term potentiation rehabilitation

DGS1 improves rice disease resistance by elevating pathogenassociated molecular pattern-triggered immunity

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aBIOTECH 2024年第1期5卷 46-51页

作者： yu Wang Chuan Zheng You-liang peng qian Chen MOA Key Lab of Pest Monitoring and Green Management and Frontiers Science Center for Molecular Design Breeding China Agricultural UniversityBeijing 100193China

Rice yield and disease resistance are two crucial factors in determining the suitability of a gene for agricultural *** grain size1(DGS1),encoding an RING-type E3 ligase,has been found to have a positive effect on rice yield by regulating rice grain number and 1000-grain ***,the role of DGS1 in rice blast resistance is still *** this study,we report that DGS1 enhances disease resistance by improving PTI responses,including stronger ROS burst and MAPK activation,and also increased expression of defense-related ***,DGS1 works in conjunction with ubiquitin conjugating enzyme OsUBC45 as an E2-E3 pair to facilitate the ubiquitin-dependent degradation of OsGSK3 and OsPIP2;1,thereby influencing rice yield and immunity,***,the DGS1-OsUBC45 module has the potential in facilitating rice agricultural breeding.

关键词： Rice blast PTI ERAD E2-E3 pair Ubiquitination

Guaranteed Cost Attitude Tracking Control for Uncertain Quadrotor Unmanned Aerial Vehicle Under Safety Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1447-1457页

作者： qian Ma peng Jin Frank L.Lewis School of Automation Nanjing University of Science and TechnologyNanjing 210094China UTA Research Institute University of Texas at ArlingtonFort WorthTexas 76118 USA IEEE

In this paper,guaranteed cost attitude tracking con-trol for uncertain quadrotor unmanned aerial vehicle(QUAV)under safety constraints is ***,an augmented system is constructed by the tracking error system and reference *** transformation aims to convert the tracking control prob-lem into a stabilization control ***,control barrier function and disturbance attenuation function are designed to characterize the violations of safety constraints and tolerance of uncertain disturbances,and they are incorporated into the reward function as penalty *** on the modified reward function,the problem is simplified as the optimal regulation problem of the nominal augmented system,and a new Hamilton-Jacobi-Bellman equation is ***,critic-only rein-forcement learning algorithm with a concurrent learning tech-nique is employed to solve the Hamilton-Jacobi-Bellman equa-tion and obtain the optimal *** proposed algorithm can not only ensure the reward function within an upper bound in the presence of uncertain disturbances,but also enforce safety *** performance of the algorithm is evaluated by the numerical simulation.

关键词： Attitude tracking control quadrotor unmanned aerial vehicle(QUAV) reinforcement learning safety constraints uncertain disturbances.

Advancements in machine learning for material design and process optimization in the field of additive manufacturing

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China Foundry 2024年第2期21卷 101-115页

作者： Hao-ran Zhou Hao Yang Huai-qian Li Ying-chun Ma Sen yu Jian shi Jing-chang Cheng peng Gao Bo yu Zhi-quan Miao Yan-peng Wei National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space Physics Beijing 100076China School of Materials Science and Engineering Nanyang Technological University639798Singapore

Additive manufacturing technology is highly regarded due to its advantages,such as high precision and the ability to address complex geometric ***,the development of additive manufacturing process is constrained by issues like unclear fundamental principles,complex experimental cycles,and high *** learning,as a novel artificial intelligence technology,has the potential to deeply engage in the development of additive manufacturing process,assisting engineers in learning and developing new *** paper provides a comprehensive overview of the research and applications of machine learning in the field of additive manufacturing,particularly in model design and process ***,it introduces the background and significance of machine learning-assisted design in additive manufacturing *** then further delves into the application of machine learning in additive manufacturing,focusing on model design and process ***,it concludes by summarizing and forecasting the development trends of machine learning technology in the field of additive manufacturing.

关键词： additive manufacturing machine learning material design process optimization intersection of disciplines embedded machine learning

A Weighted Flow related to a Trudinger–Moser Functional on Closed Riemann Surface

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2244-2262页

作者： peng Xiu yu School of Mathematics Renmin University of ChinaBeijing 100872P.R.China

In this paper,with(Σ,g)being a closed Riemann surface,we analyze the possible concentration behavior of a heat flow related to the Trudinger–Moser *** obtain a long time existence for the *** along some sequence of times t_(k)→+∞,we can deduce the convergence of the flow in H2(Σ).Furthermore,the limit function is a critical point of the Trudinger–Moser functional under certain constraint.

关键词： Trudinger-Moser inequality global convergence heat flow

BLS-identification:A device fingerprint classification mechanism based on broad learning for Internet of Things

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Digital Communications and Networks 2024年第3期10卷 728-739页

作者： yu Zhang Bei Gong qian Wang Faculty of Information Technology Beijing University of TechnologyBeijing100124China School of Information Science and Technology Zhengzhou Normal UniversityHenan450044China

The popularity of the Internet of Things(IoT)has enabled a large number of vulnerable devices to connect to the Internet,bringing huge security *** a network-level security authentication method,device fingerprint based on machine learning has attracted considerable attention because it can detect vulnerable devices in complex and heterogeneous access ***,flexible and diversified IoT devices with limited resources increase dif-ficulty of the device fingerprint authentication method executed in IoT,because it needs to retrain the model network to deal with incremental features or *** address this problem,a device fingerprinting mechanism based on a Broad Learning System(BLS)is proposed in this *** mechanism firstly characterizes IoT devices by traffic analysis based on the identifiable differences of the traffic data of IoT devices,and extracts feature parameters of the traffic packets.A hierarchical hybrid sampling method is designed at the preprocessing phase to improve the imbalanced data distribution and reconstruct the fingerprint *** complexity of the dataset is reduced using Principal Component Analysis(PCA)and the device type is identified by training weights using *** experimental results show that the proposed method can achieve state-of-the-art accuracy and spend less training time than other existing methods.

关键词： Device fingerprint Traffic analysis Class imbalance Broad learning system Access authentication

Helicobacter pylori infection alters gastric microbiota structure and biological functions in patients with gastric ulcer or duodenal ulcer

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World Journal of Gastroenterology 2024年第24期30卷 3076-3085页

作者： Ling-Xiao Jin yu-peng Fang Chen-Mei Xia Teng-Wei Cai qian-qian Li yu-Yin Wang Hai-Fan Yan Xia Chen Department of Gastroenterology Wenling Hospital of Wenzhou Medical University(The First People’s Hospital of Wenling)Wenling 317500Zhejiang ProvinceChina

BACKGROUND Helicobacter pylori(***)infection is closely associated with gastrointestinal *** preliminary studies have indicated that *** infection had a significant impact on the mucosal microbiome structure in patients with gastric ulcer(GU)or duodenal ulcer(DU).AIM To investigate the contributions of *** infection and the mucosal microbiome to the pathogenesis and progression of ulcerative *** Patients with *** infection and either GU or DU,and healthy individuals without *** infection were *** or duodenal mucosal samples was obtained and subjected to metagenomic *** compositions of the microbial communities and their metabolic functions in the mucosal tissues were *** Compared with that in the healthy individuals,the gastric mucosal microbiota in the ***-positive patients with GU was dominated by ***,with signi-ficantly reduced *** intergroup differential functions,which were enriched in the ***-positive GU patients,were all derived from ***,particularly those concerning transfer RNA queuosine-modification and the synthesis of demethylmenaquinones or menaquinones.A significant enrichment of the uibE gene was detected in the synthesis *** was no significant difference in microbial diversity between the ***-positive DU patients and healthy *** *** infection significantly alters the gastric microbiota structure,diversity,and biological functions,which may be important contributing factors for GU.

关键词： Helicobacter pylori Gastric ulcer Duodenal ulcer Metagenomic sequencing Transfer RNA queuosine-modification Menaquinones

A large language model-powered literature review for high-angle annular dark field imaging

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Chinese Physics B 2024年第9期33卷 76-81页

作者： Wenhao yuan Cheng peng qian He Department of Material Science and Engineering College of Design and EngineeringNational University of Singapore9 Engineering Drive 1EA#03-09117575Singapore Centre for Hydrogen Innovations National University of SingaporeE81 Engineering Drive 3117580Singapore

High-angle annular dark field(HAADF)imaging in scanning transmission electron microscopy(STEM)has become an indispensable tool in materials science due to its ability to offer sub-°A resolution and provide chemical information through *** study leverages large language models(LLMs)to conduct a comprehensive bibliometric analysis of a large amount of HAADF-related literature(more than 41000 papers).By using LLMs,specifically ChatGPT,we were able to extract detailed information on applications,sample preparation methods,instruments used,and study *** findings highlight the capability of LLMs to provide a new perspective into HAADF imaging,underscoring its increasingly important role in materials ***,the rich information extracted from these publications can be harnessed to develop AI models that enhance the automation and intelligence of electron microscopes.

关键词： large language models high-angle annular dark field imaging deep learning