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Recent research progress in the mechanism and suppression of fusion welding-induced liquation cracking of nickel based superalloys

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 1072-1088页

作者： Zongli Yi Jiguo Shan yue Zhao Zhenlin Zhang Aiping Wu Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China College of Engineering China Agricultural UniversityBeijing 100091China State Key Laboratory of Clean and Efficient Turbomachinery Power Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing 100084China School of Material Science and Engineering Southwest Jiaotong UniversityChengdu 610031China

Nickel-based superalloys are extensively used in the crucial hot-section components of industrial gas turbines,aeronautics,and astronautics because of their excellent mechanical properties and corrosion resistance at high *** welding serves as an effective means for joining and repairing these alloys;however,fusion welding-induced liquation cracking has been a challenging *** paper comprehensively reviewed recent liquation cracking,discussing the formation mechanisms,cracking criteria,and *** recent investigations,regulating material composition,changing the preweld heat treatment of the base metal,optimizing the welding process parameters,and applying auxiliary control methods are effective strategies for mitigating *** promote the application of nickel-based superalloys,further research on the combination impact of multiple elements on cracking prevention and specific quantitative criteria for liquation cracking is necessary.

关键词： nickel-based superalloy fusion welding liquation cracking cracking mechanism cracking suppression

An air combat maneuver pattern extraction based on time series segmentation and clustering analysis

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Defence Technology（防务技术） 2024年第6期36卷 149-162页

作者： Zhifei Xi Yingxin Kou Zhanwu Li yue Lv You Li Air Force Engineering University No.1 Baling RoadBaqiao DistrictXi'anShaanxi ProvinceChina

Target maneuver recognition is a prerequisite for air combat situation awareness,trajectory prediction,threat assessment and maneuver *** get rid of the dependence of the current target maneuver recognition method on empirical criteria and sample data,and automatically and adaptively complete the task of extracting the target maneuver pattern,in this paper,an air combat maneuver pattern extraction based on time series segmentation and clustering analysis is proposed by combining autoencoder,G-G clustering algorithm and the selective ensemble clustering analysis ***,the autoencoder is used to extract key features of maneuvering trajectory to remove the impacts of redundant variables and reduce the data dimension;Then,taking the time information into account,the segmentation of Maneuver characteristic time series is realized with the improved FSTS-AEGG algorithm,and a large number of maneuver primitives are extracted;Finally,the maneuver primitives are grouped into some categories by using the selective ensemble multiple time series clustering algorithm,which can prove that each class represents a maneuver *** maneuver pattern extraction method is applied to small scale air combat trajectory and can recognize and correctly partition at least 71.3.of maneuver actions,indicating that the method is effective and satisfies the requirements for engineering *** addition,this method can provide data support for various target maneuvering recognition methods proposed in the literature,greatly reduce the workload and improve the recognition accuracy.

关键词： Maneuver pattern extraction Data mining Fuzzy segmentation Selective ensemble clustering

Full-domain collaborative deployment method of multiple interference sources and evaluation of its deployment effect

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Defence Technology（防务技术） 2024年第2期32卷 572-595页

作者： yue Wang Fuping Sun Xian Wang Jinming Hao Kai Xiao School of Geospatial Information The PLA Information Engineering UniversityZhengzhou 450001HenanChina

This paper realizes the full-domain collaborative deployment of multiple interference sources of the global satellite navigation system(GNSS)and evaluates the deployment effect to enhance the ability to disturb the attacker and the capability to defend the GNSS during navigation *** evaluation indicators for the jamming effect of GNSS suppressive and deceptive jamming sources are first created,their evaluation models are built,and their detection procedures are sorted out,as the basis for determining the deployment *** principles for collaboratively deploying multi-jamming sources are developed to obtain the deployment structures(including the required number,structures in demand,and corresponding positions)of three single interference sources required by collaboratively ***,simulation and hardware-in-loop testing results are presented to determine a rational configuration of the collaborative deployment of multi-jamming sources in the set situation and further realize the full-domain deployment of an interference network from ground,air to *** evaluation indices for the deployment effect are finally developed to evaluate the deployment effect of the proposed configuration and further verify its reliability and rationality.

关键词： Jamming effect Multiple interference sources Collaborative deployment Effect evaluation Defense capability

Smart Gait:A Gait Optimization Framework for Hexapod Robots

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 146-159页

作者： Yunpeng Yin Feng Gao Qiao Sun yue Zhao Yuguang Xiao State Key Laboratory of Mechanical System and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China Lenovo Corporation ShanghaiChina AI Institute School of Electronic Information and Electrical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

The current gait planning for legged robots is mostly based on human presets,which cannot match the flexible characteristics of natural *** paper proposes a gait optimization framework for hexapod robots called Smart *** Gait contains three modules:swing leg trajectory optimization,gait period&duty optimization,and gait sequence *** full dynamics of a single leg,and the centroid dynamics of the overall robot are considered in the respective *** Smart Gait not only helps the robot to decrease the energy consumption when in locomotion,mostly,it enables the hexapod robot to determine its gait pattern transitions based on its current state,instead of repeating the formalistic clock-set step *** Smart Gait framework allows the hexapod robot to behave nimbly as a living animal when in 3. movements for the first *** Smart Gait framework combines offline and online optimizations without any fussy data-driven training procedures,and it can run efficiently on board in real-time after *** experiments are carried out on the hexapod robot *** results show that the energy consumption is reduced by 15.9%when in *** gait patterns can be generated spontaneously both in regular and challenge environments,and when facing external interferences.

关键词： Gait optimization Swing trajectory optimization Legged robot Hexapod robot

Deep Structure Optimization for Incremental Hierarchical Fuzzy Systems Using Improved Differential Evolution Algorithm

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1139-1158页

作者： yue Zhu Tao Zhao College of Electrical Engineering Sichuan UniversityChengdu610065China

The optimization of the rule base of a fuzzy logic system (FLS) based on evolutionary algorithm has achievednotable results. However, due to the diversity of the deep structure in the hierarchical fuzzy system (HFS) and thecorrelation of each sub fuzzy system, the uncertainty of the HFS’s deep structure increases. For the HFS, a largenumber of studies mainly use fixed structures, which cannot be selected automatically. To solve this problem, thispaper proposes a novel approach for constructing the incremental HFS. During system design, the deep structureand the rule base of the HFS are encoded separately. Subsequently, the deep structure is adaptively mutated basedon the fitness value, so as to realize the diversity of deep structures while ensuring reasonable competition amongthe structures. Finally, the differential evolution (DE) is used to optimize the deep structure of HFS and theparameters of antecedent and consequent simultaneously. The simulation results confirm the effectiveness of themodel. Specifically, the root mean square errors in the Laser dataset and Friedman dataset are 0.03.5 and 0.0725,respectively with rule counts of rules is 8 and 12, *** compared to alternative methods, the resultsindicate that the proposed method offers improvements in accuracy and rule counts.

关键词： Hierarchical fuzzy system automatic optimization differential evolution regression problem

Cortical Organoid-on-a-Chip with Physiological Hypoxia for Investigating Tanshinone IIA-Induced Neural Differentiation

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Research 2024年第3期2023卷 457-468页

作者： yue Zhi Yujuan Zhu Jinglin Wang Junqi Zhao Yuanjin Zhao Department of Rheumatology and Immunology Nanjing Drum Tower HospitalClinical Medical College of Traditional Chinese and Western MedicineNanjing University of Chinese MedicineNanjing210023China State Key Laboratory of Bioelectronics School of Biological Science and Medical EngineeringSoutheast UniversityNanjing210096China Shenzhen Research Institute Southeast UniversityShenzhen518038China

Cortical organoids represent cutting-edge models for mimic human brain development during the early and even middle stage of pregnancy, while they often fail to recreate the complex microenvironmental factors, such as physiological hypoxia. Herein, to recapitulate fetal brain development, we propose a novel cortical organoid-on-a-chip with physiological hypoxia and further explore the effects of tanshinone IIA (Tan IIA) in neural differentiation. The microfluidic chip was designed with a micropillar array for the controlled and efficient generation of cortical organoids. With low oxygen, the generated cortical organoids could recapitulate key aspects of early-gestational human brain development. Compared to organoids in normoxic culturing condition, the promoted neurogenesis, synaptogenesis and neuronal maturation were observed in the present microsystem, suggesting the significance of physiological hypoxia in cortical development. Based on this model, we have found that Chinese herbal drug Tan IIA could promote neural differentiation and maturation, indicating its potential therapeutic effects on neurodevelopmental disorders as well as congenital neuropsychiatric diseases. These results indicate that the proposed biomimetic cortical organoid-on-a-chip model with physiological hypoxia can offer a promising platform to simulate prenatal environment, explore brain development, and screen natural neuroactive components.

关键词： promoted herbal cutting

Effects of surface energy and substrate on modulus determination of biological films by conical indentation

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Science China(Technological Sciences) 2024年第6期67卷 1757-1764页

作者： DING yue LI Cheng-Ya NIU XinRui WANG Gang-Feng Department of Engineering Mechanics SVLXi’an Jiaotong UniversityXi’an710049China Department of Mechanical Engineering City University of Hong KongHong Kong SAR999077China

Micro-/nano-indentation has become prevalent in evaluating the mechanical characteristics of biological samples,such as cells and ***,the existing contact models describing conical indentation ignore the joint effects of surface energy and substrate,and consequently cannot accurately extract the Young's modulus of biological samples deposited on *** finite element methods,we examine the conical indentation of biological films on substrates while taking surface energy into *** on the dimensional analysis,the explicit relationship between load and indentation depth is achieved for films with their moduli varying from 0.001 to 100 times that of the *** the classical Sneddon's model was employed to analyze the load-depth data,the measured modulus could reach 18 times the real modulus for films on harder substrates,but only 4%of the real modulus for films on softer ***,in micro-/nano-indentations,neglecting the contribution of surface energy would result in an overestimation of the Young's modulus of films depending on the contact *** analytical expression provided here can be utilized to precisely deduce the mechanical characteristics of biological films deposited on substrate from the load and indentation depth data of a conical indentation.

关键词： biological film surface effect substrate effect indentation

Recent advances in stretchable triboelectric nanogenerators for use in wearable bioelectronic devices

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Bio-Design and Manufacturing 2024年第4期7卷 566-590页

作者： Yaling Wang Pengcheng Zhu yue Sun Pan Li Yanchao Mao College of Science Henan Agricultural UniversityZhengzhou 450002China Key Laboratory of Materials Physics of Ministry of Education School of PhysicsZhengzhou UniversityZhengzhou 450001China

Wearable bioelectronic devices have the capacity for real-time human health monitoring,the provision of tailored services,and natural interaction with smart ***,these wearable bioelectronic devices rely on conventional rigid batteries that are frequently charged or replaced and are incompatible with the skin,leading to a discontinuity in complex therapeutic tasks related to human health monitoring and human-machine *** triboelectric nanogenerator(TENG)is a high-efficiency energy harvesting technology that converts mechanical into electrical energy,effectively powering wearable bioelectronic *** study comprehensively overviews recent advances in stretchable TENG for use in wearable bioelectronic *** working mechanism of stretchable TENG is initially explained.A comprehensive discussion presents the approaches for fabricating stretchable TENG,including the design of stretchable structures and the selection of stretchable ***,applications of wearable bioelectronic devices based on stretchable TENG in human health monitoring(body movements,pulse,and respiration)and human-machine interaction(touch panels,machine control,and virtual reality)are ***,the challenges and developmental trends regarding wearable bioelectronic devices based on stretchable TENG are elaborated.

关键词： Stretchable Triboelectric nanogenerators Structure Human health monitoring Human-machine interaction

Asymmetric Electrolytes Design for Aqueous Multivalent Metal Ion Batteries

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Nano-Micro Letters 2024年第3期16卷 227-253页

作者： Xiaochen Yang Xinyu Wang yue Xiang Longtao Ma Wei Huang Frontiers Science Center for Flexible Electronics Institute of Flexible ElectronicsNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China School of Materials Science and Engineering Guangdong Provincial Key Laboratory of Advanced Energy Storage MaterialsSouth China University of TechnologyGuangzhou 510641People’s Republic of China

With the rapid development of portable electronics and electric road vehicles,high-energy-density batteries have been becoming front-burner ***,homogeneous electrolyte cannot simultaneously meet diametrically opposed demands of high-potential cathode and low-potential anode,which are essential for high-voltage ***,homogeneous electrolyte is difficult to achieve bi-or multi-functions to meet different requirements of *** comparison,the asymmetric electrolyte with bi-or multi-layer disparate components can satisfy distinct requirements by playing different roles of each electrolyte layer and meanwhile compensates weakness of individual ***,the asymmetric electrolyte can not only suppress by-product sedimentation and continuous electrolyte decomposition at the anode while preserving active substances at the cathode for high-voltage batteries with long cyclic *** this review,we comprehensively divide asymmetric electrolytes into three categories:decoupled liquid-state electrolytes,bi-phase solid/liquid electrolytes and decoupled asymmetric solid-state *** design principles,reaction mechanism and mutual compatibility are also studied,***,we provide a comprehensive vision for the simplification of structure to reduce costs and increase device energy density,and the optimization of solvation structure at anolyte/catholyte interface to realize fast ion transport kinetics.

关键词： Asymmetric electrolyte Aqueous multivalent metal ion batteries Electrochemical stability windows Electrolyte interface