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Rare Metals 2024年第3期43卷 1177-1185页

作者： Fu-Hai Guo Lan-Zhong Hao Wei-Zhuo Yu si-Qi Li Guan-Chu liu Jing-Yi Hao Yun-Jie liu College of Science China University of PetroleumQingdao266580China School of Materials Science and Engineering China University of PetroleumQingdao266580China

As a typical candidate of optoelectronic materials,vanadium dioxide(VO_(2))has wide applications in photodetectors(PDs),but is still challenging in largely enhancing the photodetecting performance for low-power human ***,high-performance si/VO_(2)nanorods(NRs)heterojunction PDs based on the photothermoelectric(PTE)effect are *** uniform VO_(2)-NRs array films were deposited on si by using magnetron sputtering technique,and a si/VO_(2)heterojunctions were *** device exhibits a four-stage photoresponse and broadband photoresponse from ultraviolet to long-wavelength *** from the unique nanorods structure and the strong PTE effect,the fabricated device exhibits a large enhancement of the photodetecting performance,showing an ultrahigh photodetectivity of 1.6×10^(13)Jones and ultrafast response rates with a risingedge time of~65.0μs,three orders of magnitude higher than other VO_(2)-based ***,the device exhibits unique abilities to detect human radiation even when the human fingers are far away from the device surface up to 10.0 ***,the fabricated si/VO_(2)devices can also be applied as breath sensors to distinguish different breathing *** results supply an effective route to design high-performance photodetectors toward detecting human thermal radiation and respiration.

关键词： Vanadium dioxide Heterojunction Photodetector Photothermoelectric Human radiation and respiration sensing

Jianqu,a traditional Chinese medicine,alleviates functional dyspepsia in high-calorie and high-protein diet mice

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Traditional Medicine Research 2024年第6期9卷 42-54页

作者： Jing-Yan yang Xiao-Xing Li Juan Chen Yan-Jun liu Yue-Hong Wu Ning-Yu Luo Cai-Xia yang yang Li si-Jing liu Jin-Lin Guo College of Medical Technology Chengdu University of Traditional Chinese MedicineChengdu 611137China Chongqing Key Laboratory of sichuan-Chongqing Co-construction for Diagnosis and Treatment of Infectious Diseases Integrated Traditional Chinese and Western Medicine Chengdu 611137China Key Laboratory of Characteristic Chinese Medicine Resources in Southwest China College of PharmacyChengdu University of Traditional Chinese MedicineChengdu 611137China

Background:Jianqu has been used to alleviate symptoms in patients with functional dyspepsia,but its specific anti-functional dyspepsia effect is still ***,our study aimed to investigate the impact of Jianqu on functional dyspepsia in ***:The phytochemical profile of Jianqu was analyzed by ***,Kunming mice were fed a high-calorie or high-protein diet(HCHP)for 7 days,and then orally treated with vehicle or Jianqu(1.62 g/kg body weight(b.w.)and 3.25 g/kg b.w.)for 10 days.A carbon powder solution was used to detect the gastric emptying and intestinal transit *** pathological changes in stomach and duodenum were evaluated by hematoxylin-eosin *** occludin,claudin-1,ZO-1 and CD45 expression was measured by immunocytochemical ***,the serum gastrointestinal hormones were detected by *** addition,the gut microbiota composition was determined using 16S rRNA gene *** cecal short chain fatty acids were assessed by gas ***:In general,17 phytochemical compounds were identified from Jianqu,which significantly improved the gastric emptying rate and intestinal transit rate(psignificant pathological lesions in the gastrointestinal tract,increased the expression of CD45 in the duodenum(psion of CD45(psignificantly normalized by Jianqu intervention(psion:The present results showed that Jianqu alleviated dyspeptic symptoms in HCHP mice possibly through reducing the duodenal leukocyte infiltration,and regulating the expression of gastrointestinal *** effects may be partly related to the increasing cecal short ch

关键词： herbal formula dyspepsia gastrointestinal hormones gastric emptying intestinal transit

Research on concrete structure defect repair based on three-dimensional printing

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Frontiers of Structural and Civil Engineering 2024年第5期18卷 731-742页

作者： yang GU Wei LI Xupeng YAO Guangjun liu School of Mechanical Engineering Tongji UniversityShanghai 201804China College of Civil Engineering Tongji UniversityShanghai 200092China Shanghai Engineering Research Center for Safety Intelligent Control of Building Machinery Shanghai 200032China

Quality assurance and maintenance play a crucial role in engineering construction,as they have a significant impact on project *** common issue in concrete structures is the presence of *** enhance the automation level of concrete defect repairs,this study proposes a computer vision-based robotic system,which is based on three-dimensional(3D)printing technology to repair *** system integrates multiple sensors such as light detection and ranging(LiDAR)and *** is utilized to model concrete pipelines and obtain geometric parameters regarding their ***,a convolutional neural network(CNN)is employed with a depth camera to locate defects in concrete ***,a method for coordinate transformation is presented to convert the obtained coordinates into executable ones for a robotic ***,the feasibility of this concrete defect repair method is validated through simulation and experiments.

关键词： concrete defect detection 3D printing deep learning point cloud data

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基于线性加权数据融合的协作频谱感知优化

电子科技大学学报 2012年第5期41卷 697-701,786页

作者：刘全高俊郭云玮刘思洋中国电子系统设备工程公司研究所北京丰台区100141 海军工程大学通信工程系武汉430033

在认知无线电网络中,协作频谱感知技术可有效地缓解本地感知场景中存在的隐藏终端等问题。为了获得更大的协作增益,该文采用基于数据融合的协作频谱感知策略,融合中心依次收集各次用户上报的本地能量检测数据,然后进行线性加权融合,并... 详细信息

在认知无线电网络中,协作频谱感知技术可有效地缓解本地感知场景中存在的隐藏终端等问题。为了获得更大的协作增益,该文采用基于数据融合的协作频谱感知策略,融合中心依次收集各次用户上报的本地能量检测数据,然后进行线性加权融合,并做出最终判决。重点研究了线性加权融合方案的优化,推导了各次用户分别在Neyman-Pearson(N-P)和Bayesian两种不同准则下的最优融合权重,并在Suzuki感知信道下进行了蒙特卡洛仿真和数值验证。结果表明,N-P准则下给出的两种优化加权融合方案MDC和NDC性能相近,且均比EGC、SC、MRC等常用的融合方案具有更高的协作检测概率;而Bayesian准则下推导的优化加权融合方案BAY在检测可靠性方面明显优于其他方案。

关键词： Bayesian准则认知无线电数据融合能量检测 Neyman-Pearson准则频谱感知

On the Probability of Generating a Primitive Matrix

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Journal of Systems Science & Complexity 2024年第4期37卷 1755-1771页

作者： CHEN Jingwei FENG Yong liu yang WU Wenyuan Chongqing Key Laboratory of Automated Reasoning and Cognition Chongqing Institute of Green and Intelligent TechnologyChinese Academy of SciencesChongqing 400714China Chongqing College University of Chinese Academy of SciencesChongqing 400714China Key Laboratory of Advanced Manufacturing Technology of Ministry of Education Guizhou UniversityyGuiyang 550025China Information Science and Engineering Chongqing Jiaotong UniversityChongqing 400074China

Given a k×n integer primitive matrix A(i.e.,a matrix can be extended to an n×n unimodular matrix over the integers)with the maximal absolute value of entries‖A‖bounded by an integer λ from above,the authors study the probability that the m×n matrix extended from A by appending other m-k row vectors of dimension n with entries chosen randomly and independently from the uniform distribution over{0,1,…,λ-1}is still *** authors present a complete and rigorous proof of a lower bound on the probability,which is at least a constant for fixed m in the range[k+1,n-4].As an application,the authors prove that there exists a fast Las Vegas algorithm that completes a k×n primitive matrix A to an n×n unimodular matrix within expected O(n^(ω)log‖A‖)bit operations,where O is big-O but without log factors,ω is the exponent on the arithmetic operations of matrix multiplication.

关键词： Integer matrix matrix completion probabilistic algorithm unimodular matrix

Regulating Effect of Substrate Temperature on Sputteringgrown Ge/si QDs under Low Ge Deposition

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 888-894页

作者：舒启江 yang Linjing liu Hongxing 黄鹏儒 Institute of Information Yunnan University of Chinese MedicineKunming 650500China Guangxi Key Laboratory of Information Materials and Guangxi Collaborative Innovation Center of Structure and Property for New Energy and Materials School of Material Science&EngineeringGuilin University of Electronic TechnologyGuilin 541004China

The effect of deposition temperature on the morphology and optoelectronic performance of Ge/si QDs grown by magnetron sputtering under low Ge deposition(~4 nm)was investigated by atomic force microscopy,Raman spectroscopy,and photoluminescence(PL)*** experimental results indicate that temperatures higher than 750℃effectively increase the crystallization rate and surface smoothness of the si buffer layer,and temperatures higher than 600℃significantly enhance the migration ability of Ge atoms,thus increasing the probability of Ge atoms meeting and nucleating to form QDs on si buffer layer,but an excessively high temperature will cause the QDs to undergo an Ostwald ripening process and thus develop into super large *** addition,some PL peaks were observed in samples containing small-sized,high-density Ge QDs,the photoelectric properties reflected by these peaks were in good agreement with the corresponding structural characteristics of the grown *** results demonstrate the viability of preparing high-quality QDs by magnetron sputtering at high deposition rate,and the temperature effect is expected to work in conjunction with other controllable factors to further regulate QD growth,which paves an effective way for the industrial production of QDs that can be used in future devices.

关键词： Ge/si QDs deposition temperatures evolution law photoelectric performance

Progress on the program of si-compatible two-dimensional semiconductor materials and devices

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Science China(Information Sciences) 2024年第6期67卷 152-171页

作者： Mingsheng XU Yuwei WANG Jiwei liu Deren yang College of Integrated Circuits State Key Laboratory of Silicon and Advanced Semiconductor MaterialsZhejiang University School of Materials Science and Engineering State Key Laboratory of Silicon and Advanced Semiconductor MaterialsZhejiang University

Two-dimensional(2D) materials are at the forefront of innovation, heralding a new era for nextgeneration electronics and optoelectronics. These materials are distinguished by their unique structural characteristics: they have no hanging bonds on their surface, exhibit weakened electrostatic shielding in the Z-direction, and boast atomic thickness in their monolayers. These features have led to groundbreaking discoveries in electrical, optical, and magnetic properties, paving the way for advancements in low-power electronics, valleytronics, infrared detectors, and memory devices. Despite these promising developments,si-based technologies continue to dominate the landscape of next-generation electronics and optoelectronics,as well as heterogeneous integration. In response to this ongoing evolution, the National Natural Science Foundation of China(NSFC) initiated a major program in 2021 dubbed “si-compatible two-dimensional semiconductor materials and devices”. This study reviews the progress made under the NSFC Program,spotlighting its main achievements and outlining key future research directions. Additionally, it sheds light on the challenges that researchers in the 2D domain face, particularly in developing si-compatible 2D technologies.

关键词： two-dimensional materials si-based CMOS technologies electronics and optoelectronics heterogeneous integration low-power

Adaptive multi-channel Bayesian graph attention network for IoT transaction security

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Digital Communications and Networks 2024年第3期10卷 631-644页

作者： Zhaowei liu Dong yang Shenqiang Wang Hang Su School of Computer and Control Engineering Yantai UniversityYantai264005China Department of Electronics Information and BioengineeringPolitecnico di MilanoMilan20133Italy

With the rapid advancement of 5G technology,the Internet of Things(IoT)has entered a new phase of appli-cations and is rapidly becoming a significant force in promoting economic *** to the vast amounts of data created by numerous 5G IoT devices,the Ethereum platform has become a tool for the storage and sharing of IoT device data,thanks to its open and tamper-resistant ***,Ethereum account security is necessary for the Internet of Things to grow quickly and improve people's *** modeling Ethereum trans-action records as a transaction network,the account types are well identified by the Ethereum account classifi-cation system established based on Graph Neural Networks(GNNs).This work first investigates the Ethereum transaction ***,experimental metrics reveal that the Ethereum transaction network is neither optimal nor even satisfactory in terms of accurately representing transactions per *** flaw may significantly impede the classification capability of GNNs,which is mostly governed by their *** work proposes an Adaptive Multi-channel Bayesian Graph Attention Network(AMBGAT)for Ethereum account clas-sification to address this *** uses attention to enhance node features,estimate graph topology that conforms to the ground truth,and efficiently extract node features pertinent to downstream *** extensive experiment with actual Ethereum transaction data demonstrates that AMBGAT obtains competitive performance in the classification of Ethereum accounts while accurately estimating the graph topology.

关键词： Internet of things Graph representation learning Node classification Security mechanism

Bionic Design and Experimental Validation of a Robotic Airship Inspired by the Physalia physalis

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Journal of Bionic Engineering 2024年第2期21卷 740-753页

作者： Yueneng yang Lili Chen Zhiyang liu Shifeng Zhang College of Aerospace Science and Engineering National University of Defense TechnologyNo.109Deya RoadKaiFu DistrictChangsha410073China Aerospace Technology Institute China Aerodynamics Research and Development CenterMianyang621000China

The robotic airship is one of the most unique and promising green aircraft,however,as a“lighter-than-air aircraft”and“thermal aircraft”,its long-endurance flight has great difficulties in decreasing drag and controlling buoyancy and pressure under thermal *** this work,we reported a robotic airship inspired by the Physalia physalis,imitating its morphology,physiological structure,and biological *** hull is designed by imitating the morphology of the Physalia physalis,and the gasbags including a helium balloon,two ballonets,and a thermoregulation gasbag are designed by imitating the physiological structure and biological behaviors of the pneumatophore,bladder,and gland of the Physalia physalis,*** results show that the bionic airship has an increase of about 40%in lift-to-drag and decreases the pressure in helium balloon by 47.5%under thermal effects,and has better aerodynamic performances and thermoregulation performances than conventional airships.

关键词： Robotic airship Bionic design Aerodynamic performances Thermoregulation Physalia physalis

Reynolds-number scaling analysis on lift generation of a flapping and passive rotating wing with an inhomogeneous mass distribution

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Chinese Journal of Aeronautics 2024年第2期37卷 259-269页

作者： Suyang QIN Haotian HANG yang XIANG Hong liu J.C.Wu center for aerodynamics school of aeronautics and astronauticsshanghai jiao tong universityshanghai 200240china

Insects usually fly by passively rotating wings,which has been applied to the design of flapping-wing Micro-Air Vehicles(MAVs)to reduce mechanical *** this paper,a robotic passive rotating-wing model is designed to investigate wing kinematics and lift generation,which are measured by a high-speed camera and a force transducer,*** addition,flow fields are measured using the Particle Image Velocimetry(PIV).Experimental results demonstrate that passive rotating motion has a coordinative relationship with actively stroking *** the stroke amplitude or frequency increases,the rotating amplitude is *** characterize the active stroking motion,a driving Reynolds number Redrivingis defined,which varies from 68 to 366 in this *** the gravity center of the wing towards trailing ed ge induces the increase of additional torque M,which decreases the wing rotating amplitude and promotes the advance of wing *** find that the timing of wing rotation is gradually delayed and the mean lift coefficient C^(-)_(L)monotonously decreases as *** increasing the additional torque M,C^(-)_(L)is slightly improved and approaches to the lift coefficient of a real fruit fly at driving Re approximately equal to *** instantaneous lifts combined with the vortical structures further demonstrate that the lift generation associated with wing rotation is mainly attributed to the growth of the LeadingEdge Vortex(LEV)and the passive wake capture *** wake capture is influenced by LEV,reversal stroke motion and wing additional torque together,which can only maintain the lift at a high level for a considerable *** high-lift generation mechanisms of flapping and passive rotating flight could shed light on the simplified design of MAVs and the improvement of their aerodynamic performance.

关键词： Flapping flight Unsteady lift Passive rotation Vortex flow Leading-edge vortex