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基于骨架线特征识别的激光选区熔化区域性能匹配成形方法

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机械工程学报 2024年第15期60卷 272-282页

作者：何骏驰张李超王森林汤名锴史玉升华中科技大学材料科学与工程学院武汉430074 武汉科技大学机械自动化学院武汉430081

对于激光选区熔化成形存在如薄壁和尖角等特征区域的零件,不同特征区域在真实服役场景下的性能需求和与之匹配的最佳工艺策略不尽相同。针对现有激光选区熔化工艺规划及加工软件中缺乏支持各类特征区域提取并匹配不同工艺策略的情况,提... 详细信息

对于激光选区熔化成形存在如薄壁和尖角等特征区域的零件,不同特征区域在真实服役场景下的性能需求和与之匹配的最佳工艺策略不尽相同。针对现有激光选区熔化工艺规划及加工软件中缺乏支持各类特征区域提取并匹配不同工艺策略的情况,提出一种基于骨架线特征识别的激光选区熔化区域性能匹配成形方法,实现薄壁、尖角和大平面等区域匹配性能需求工艺策略的一体化成形。通过仿真或实验确定各特征区域的性能需求,再提取切片轮廓的主骨架线,并依据其特征对切片轮廓进行区域划分,同时通过工艺数据库确定匹配各区域性能需求的工艺策略,将匹配性能需求的工艺策略赋予相应区域并打印成形零件。使用Ti6Al4V材料打印航空航天中常用的叶轮零件等比例缩小模型进行实验,确定叶轮的性能需求为中心处所需抗拉强度大和叶片处所需塑性好,提取叶轮切片轮廓并设置分区参数从而划分叶轮中心处和叶片处,然后将实验得到的工艺策略分别赋予叶轮中心处和叶片处并打印成形零件,最后对两处的微观组织进行分析,验证了方法的可行性。本项目所提出的基于骨架线特征识别的SLM区域性能匹配成形方法可有效实现区域性能可调控零件的一体化制造,使零件在服役过程满足不同区域对性能的差异化需求,为高性能零件一体化成形提供有效手段。

关键词：激光选区熔化骨架线特征识别成形方法

Simple Fabrication of Hierarchical Micro/Nanostructure Superhydrophobic Surface with Stable and Superior Anticorrosion Silicon Steel via Laser Marking Treatment

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Journal of Wuhan University of Technology(Materials Science) 2020年第2期35卷 411-417页

作者： FU Jing tang mingkai ZHANG Qiaoxin School of Mechanical and Electronic Engineering Henan Institute of TechnologyXinxiang 453003China School of Mechanical and Electronic Engineering Wuhan University of TechnologyWuhan 430070China

To improve the weak corrosion resistance of silicon steel to acid solution and alkaline solution with high temperature,a stable hierarchical micro/nanostructure superhydrophobic surface with myriad irregular micro-scale hump and sheet-like nanostructure was successfully prepared on silicon steel by a simple,efficient and facile operation in large-area laser marking *** morphology,composition,wettability of the as-prepared surface were *** superhydrophobic performance of the surface was investigated as ***,the corrosion resistance of the superhydrophobic surface to acidic solutions at room temperature and alkaline solutions at high temperature (80 ℃) was carefully *** corrosion resistance mechanism was ***,considering the practical application of the surface in the future,the hardness of the hierarchical micro/nanostructure superhydrophobic surface was *** experimental results indicate that the hierarchical micro/nanostructure surface with texture spacing of 100 μm treated at laser scanning speed of 100 mms/ presents superior superhydrophobicity after decreasing surface *** contact angle can be as high as 156.6°.Additionally,the superhydrophobic surface provide superior and stable anticorrosive protection for silicon steel in various corrosive *** importantly,the prepared structure of the surface shows high hardness,which ensures that the surface of the superhydrophobic surface cannot be destroyed *** surface is able to maintain great superhydrophobic performance when it suffers from slight impacting and abrasion.

关键词： silicon steel laser marking hierarchical micro/nanostructure superhydrophobic surface corrosion resistance

Assessment of piloting behavior impact on landing risk of transport aircraft

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CHINESE JOURNAL OF AERONAUTICS 2024年第9期37卷 178-192页

作者： Xiong, Zhiyue Zhang, Shuguang Wang, mingkai tang, Peng Wang, Mengmeng Beihang Univ Sch Transportat Sci & Engn Beijing 102206 Peoples R China

The human factors and their interaction with other factors play an important role in the flight safety of transport aircraft. In this paper, a paradigm of risk assessment for transport aircraft interacting with piloting behaviors is proposed, with focus on landing which is the most accidentprone flight stage in aviation safety statistics. Model-based flight simulation serves as our data source for landing risk analysis under uncertainties. A digital pilot in the loop that reflects the human piloting behaviors is employed to facilitate simulation efficiency. Eight types of unsafe events in landing are identified from statistics. On this basis, the landing safety boundary is extracted via stochastic simulation to divide safety and hazardous flight status domains, which contributes to flight status management and risk warning. The simulation results indicate that appropriate piloting behavior, which is active response and fast target acquisition with minimum overshoot and fluctuation, shows benefit to landing safety. The subset simulation technique is employed to further refine the boundary with less computational workload. Furthermore, the effect of airspeed, windspeed, and other factors on landing risk is also discussed. The proposed risk assessment method would help optimize operation procedure and develop targeted pilot training program. (c) 2024 Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics. This is an open access article under the CC BY-NC-ND license (http://***/ licenses/by-nc-nd/4.0/).

关键词： Landing risk assessment Risk parameterization Human factors Piloting behavior model Landing safety boundary Subset simulation IDENTIFICATION MODELS

Effect of defatted flaxseed gum powder addition on the quality of sesame paste

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Oil Crop Science 2024年第1期9卷 1-7页

作者： Haichao He mingkai Sun Jiahui Wang Yan tang Yashu Chen Qianchun Deng Qingde Huang Hu tang Oil Crops Research Institute Chinese Academy of Agricultural SciencesWuhanChina Hubei Key Laboratory of Lipid Chemistry and Nutrition WuhanChina Oil Crops and Lipids Process Technology National&Local Joint Engineering Laboratory WuhanChina

The study explored the influence of defatted flaxseed gum powder(DFGP) on the stability and quality of sesame paste by measuring and analyzing its composition, color, texture, particle size, centrifugal oil separation rate,rheological properties, and microstructure. The results showed that the moisture and polysaccharide content of sesame paste was increased as the DFGP increased. Additionally, the hardness, gumminess, and chewiness of the sesame paste was improved, while the presence of particles with small particle size(1–100 μm) was *** rate of oil precipitation was reduced by 28.99% when the amount of DFGP was 6%. The sesame paste samples exhibited pseudoplastic behavior, demonstrating shear thinning. As the shear rate increased, the apparent viscosity of sesame paste gradually decreased. Both the storage modulus(G’) and the loss modulus(G’’) increased as the shear frequency increased. The microstructure observation revealed that protein and oil were evenly distributed in the sesame paste system, and the addition of DFGP enhanced the bonding between oil and *** study can provide valuable references for high-quality sesame paste products in the food industry.

关键词： Flaxseed gum powder Sesame paste Quality Addition

Topologically protected entanglement switching around exceptional points

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Light(Science & Applications) 2024年第8期13卷 1631-1644页

作者： Zan tang Tian Chen Xing tang Xiangdong Zhang Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurements of Ministry of Education Beijing Key Laboratory of Nanophotonics&Ultrafine Optoelectronic SystemsSchool of PhysicsBeijing Institute of Technology100081 BeijingChina

The robust operation of quantum entanglement states is crucial for applications in quantum information,computing,and communications^(1–3).However,it has always been a great challenge to complete such a task because of decoherence and ***,we propose theoretically and demonstrate experimentally an effective scheme to realize robust operation of quantum entanglement states by designing quadruple degeneracy exceptional *** encircling the exceptional points on two overlapping Riemann energy surfaces,we have realized a chiral switch for entangled states with high *** to the topological protection conferred by the Riemann surface structure,this switching of chirality exhibits strong robustness against perturbations in the encircling ***,we have experimentally validated such a scheme on a quantum walk *** work opens up a new way for the application of non-Hermitian physics in the field of quantum information.

关键词： exceptional quantum Riemann

An economic way to achieve all-weather CO2 reduction

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National Science Review 2024年第3期11卷 46-47页

作者： Junwang tang Department of Chemical Engineering University College London

Utilising solar power to convert carbon dioxide（CO2） into hydrocarbon fuels presents an eco-friendly method to address dependence on fossil fuels and contribute to a net-zero CO2emission goal[1,2].

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UAV-assisted data collection for wireless sensor networks with dynamic working modes

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Digital Communications and Networks 2024年第3期10卷 805-812页

作者： Jie Chen Jianhua tang Shien-Ming Wu School of Intelligent Engineering South China University of TechnologyGuangzhou511442China

Wireless Sensor Network(WSN)is a cornerstone of Internet of Things(IoT)and has rich application *** this work,we consider a heterogeneous WSN whose sensor nodes have a diversity in their Residual Energy(RE).In this work,to protect the sensor nodes with low RE,we investigate dynamic working modes for sensor nodes which are determined by their RE and an introduced energy ***,we employ an Unmanned Aerial Vehicle(UAV)to collect the stored data from the heterogeneous *** aim to jointly optimize the cluster head selection,energy threshold and sensor nodes’working mode to minimize the weighted sum of energy con-sumption from the WSN and UAV,subject to the data collection rate *** this end,we propose an efficient search method to search for an optimal energy threshold,and develop a penalty-based successive convex approximation algorithm to select the cluster *** we present a low-complexity iterative approach to solve the joint optimization problem and discuss the implementation *** results justify that our proposed approach is able to reduce the energy consumption of the sensor nodes with low RE significantly and also saves energy for the whole WSN.

关键词： Unmanned aerial vehicle Wireless sensor networks Cluster heads Dynamic working modes

Highly effective design of high GFA alloys with different metalbased and various components by machine learning

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Science China(Technological Sciences) 2024年第5期67卷 1431-1442页

作者： tang YiChuan HE YiFan FAN ZhuoQun WANG ZhongQi tang ChengYing Guangxi Key Laboratory for Informational Materials School of Materials Science and EngineeringGuilin University of Electronic TechnologyGuilin541004China

The glass-forming ability(GFA)is of great significance for the development of novel functional metal-based metallic *** this study,seven popular machine learning(ML)algorithms were employed to design novel M-based(M=Fe,Co,Ni,Ti,Zr,and rare earth metal(RE))and X-component(X=2,3,4,5,6,and>6)alloys with excellent GFA.A GFA containing 6957 data points with structural analysis was *** engineering was used to analyze the importance and correlation of *** algorithms were utilized for GFA prediction,revealing that Xtreme Gradient Boosting Trees exhibited the strongest predictive capability,achieving a high accuracy of 94.0%,a true positive rate of 97.6%,and a root mean squared error of 0.3705 across the entire ***,the GFA of ternary to hexahydroxy alloys based on Fe,Co,Ni,Zr,Ti,and Y was predicted using all possible compositions generated through ***,a series of alloys with good GFA was successfully designed and *** present work suggests that the proposed ML method can be utilized to design novel multiple-M-based amorphous alloys with high GFA.

关键词： machine learning amorphous alloy feature engineering materials design glass forming ability

Characteristic Analysis of Power Oscillations Caused by Disharmony Among Voltage-source-controlled Units in Three-terminal Local Power Grid

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Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1295-1308页

作者： Qiyi Yu Yi tang School of Electrical Engineering Southeast UniversityNanjing 210018China

Previous studies have demonstrated that disharmo-ny among voltage-source-controlled units(VSCUs)may occur on an alternating current(AC)transmission or distribution line under steady-state operating conditions(SSOCs)or quasi-static operating conditions(QSSOCs).As the studies on frequency dis-harmony have been expanded to multiple disharmonized vS-CUs in the local power grid,its adverse effects on AC lines and equivalent load(EL)at the bus without active voltage control ability(non-active bus)need to be investigated ***-ering the locality of disharmony and common topological con-nections among VSCUs,this paper adopts a Y-type three-termi-nal local power grid(LPG)as the research *** dishar-mony among the three VSCUs is ***,for the load at non-active bus,the formulas for single-phase instantaneous voltage,load current,load power,as well as average power un-der disharmony operating conditions(DOCs)are *** characteristic indicators of the above electrical quantities are defined,which can measure the amplification and reduction de-grees of the above electrical quantities before and after ***,for the line directly connected to VSCUs,the formulas for single-phase instantaneous line current and power and the average power under DOCs are *** character-istic indicators of power flow are defined,which can be used to quantify the peak amplification impact of oscillation before and after ***,the case study on the Y-type three-terminal LPG under the single-disharmony and the multi-dis-harmony switching scenarios indicates that the long-period pow-er oscillation caused by disharmony may occur in the load flow at the non-active bus and the line *** oscillation causes a serious decrease in load capability and a significant amplifica-tion of the peak of line power oscillation.

关键词： New power system power oscillation disharmony voltage-source-controlled unit(VSCU) characteristic analysis