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Journal of Contemporary Educational Research 2023年第12期7卷 358-366页

作者： Yu Ma xi’an mingde institute of technology Xi’an 710000Shaanxi ProvinceChina

With the government’s strong support and investment in higher education,private colleges and universities have become an important part of higher *** evaluation is an important means of monitoring the quality of teaching in colleges and universities and a crucial way to improve teaching *** article takes xi’an mingde institute of technology as an example to explore the practice and development of teaching evaluation in private colleges and universities.

关键词： Private colleges and universities Teaching evaluation Practice Development

Warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo photography

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Defence technology（防务技术） 2024年第7期37卷 162-172页

作者： Pengyu Hu Jiangpeng Wu Zhengang Yan Meng He Chao Liang Hao Bai xi'an Modern Control technology Research institute Xi'an710065China xi'an OET Science and technology Co. LtdXi'an710076China

High speed photography technique is potentially the most effective way to measure the motion parameter of warhead fragment benefiting from its advantages of high accuracy,high resolution and high ***,it faces challenge in dense objects tracking and 3D trajectories reconstruction due to the characteristics of small size and dense distribution of fragment *** address these challenges,this work presents a warhead fragments motion trajectories tracking and spatio-temporal distribution reconstruction method based on high-speed stereo ***,background difference algorithm is utilized to extract the center and area of each fragment in the image ***,a multi-object tracking(MOT)algorithm using Kalman filtering and Hungarian optimal assignment is developed to realize real-time and robust trajectories tracking of fragment *** reconstruct 3D motion trajectories,a global stereo trajectories matching strategy is presented,which takes advantages of epipolar constraint and continuity constraint to correctly retrieve stereo correspondence followed by 3D trajectories refinement using polynomial ***,the simulation and experimental results demonstrate that the proposed method can accurately track the motion trajectories and reconstruct the spatio-temporal distribution of 1.0×10^(3)fragments in a field of view(FOV)of 3.2 m×2.5 m,and the accuracy of the velocity estimation can achieve 98.6%.

关键词： Warhead fragment measurement High speed photography Stereo vision Multi-object tracking Spatio-temporal reconstruction

Reinforcement Learning Based Quantization Strategy Optimal Assignment Algorithm for Mixed Precision

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Computers, Materials & Continua 2024年第4期79卷 819-836页

作者： Yuejiao Wang Zhong Ma Chaojie Yang Yu Yang Lu Wei xi’an Microelectronics technology institute Xi’an710065China

The quantization algorithm compresses the original network by reducing the numerical bit width of the model,which improves the computation speed. Because different layers have different redundancy and sensitivity to databit width. Reducing the data bit width will result in a loss of accuracy. Therefore, it is difficult to determinethe optimal bit width for different parts of the network with guaranteed accuracy. Mixed precision quantizationcan effectively reduce the amount of computation while keeping the model accuracy basically unchanged. In thispaper, a hardware-aware mixed precision quantization strategy optimal assignment algorithm adapted to low bitwidth is proposed, and reinforcement learning is used to automatically predict the mixed precision that meets theconstraints of hardware resources. In the state-space design, the standard deviation of weights is used to measurethe distribution difference of data, the execution speed feedback of simulated neural network accelerator inferenceis used as the environment to limit the action space of the agent, and the accuracy of the quantization model afterretraining is used as the reward function to guide the agent to carry out deep reinforcement learning training. Theexperimental results show that the proposed method obtains a suitable model layer-by-layer quantization strategyunder the condition that the computational resources are satisfied, and themodel accuracy is effectively *** proposed method has strong intelligence and certain universality and has strong application potential in thefield of mixed precision quantization and embedded neural network model deployment.

关键词： Mixed precision quantization quantization strategy optimal assignment reinforcement learning neural network model deployment

Research on the Development Path and Mechanism of“Double-Qualified”Teachers in Private Universities Under the Background of Digital Transformation

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Journal of Contemporary Educational Research 2024年第2期8卷 236-242页

作者： Min Liu xi’an mingde institute of technology Xi’an 710000Shaanxi ProvinceChina

This article explores the development path and mechanism of“double-qualified”teachers in private universities under digital *** literature review,theoretical analysis,and other research methods,this study conducts an in-depth analysis of the impact of digital technology on the development of“double-qualified”teachers in private colleges and universities and puts forward corresponding strategies and *** shows that digital transformation provides new opportunities and challenges for developing“double-qualified”teachers in private colleges and *** adapt to this trend,teachers must continuously improve their digital skills,and schools should establish a complete incentive mechanism and evaluation system,strengthen school-enterprise cooperation and the integration of industry and education to promote the comprehensive development of“double-qualified”teachers,and provide a useful guideline for private universities to promote the development of“double-qualified”teachers in digital transformation.

关键词： Digitalization Private universities “Double-qualified” Development path

Formation behaviors of rod-like reactive shaped charge penetrator and their effects on damage capability

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Defence technology（防务技术） 2024年第2期32卷 242-253页

作者： Tao Sun Haifu Wang Shipeng Wang Chao Ge Die Hu Pengwan Chen Yuanfeng Zheng Beijing institute of technology State Key Laboratory of Explosion Science and TechnologyBeijing100081China xi'an institute of Electromechanical Information technology Xi'an710065China

Formation behaviors of rod-like reactive shaped charge penetrator(RRSCP)and their effects on damage capability are investigated by experiments and numerical *** pulsed X-ray technology and a spaced aluminum/steel plate with the thicknesses of 5 mm/100 mm are *** types of sphericalsegment aluminum-polytetrafluoroethylene-copper(Al-PTFE-Cu)reactive liners with Cu contents of 0%,46.6%,and 66%are fabricated and *** experimental results show that the reactive liners can form excellent rod-shaped penetrators with tail skirts under the shaped charge effect,but the tail skirts disappear over ***,rupturing damage to the aluminum plate and penetration to the steel plate are caused by the RRSCP *** simulation analysis,the RRSCP is formed by a mechanically and chemically coupled response with the reactive liner activated by shock in its outer walls and bottom and then backward overturning,forming a leading reactive penetrator and a following chemical energy *** unique formation structure determines the damage modes of the aluminum plate and the steel *** analysis indicates that the formation behaviors and damage capability of Al-PTFE-Cu RRSCP strongly depend on Cu *** increasing Cu content,the velocity,activation extent,and reaction extent of Al-PTFE-Cu RRSCP decrease,which contribute to elongation and alleviate the negative effects of chemical reactions on elongation,significantly increasing the length-diameter ratio and thus enhancing the capability of steel plate ***,the lower activation extent and energetic density will weaken the RRSCP's capability of causing rupturing damage to the aluminum plate.

关键词： Reactive materials Al-PTFE composites Reactive liner X-ray Penetration

Highly efficient photo-thermal synergistic catalysis of CO_(2)methanation over La_(1-x)Ce_(x)NiO_(3)perovskite-catalyst

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Nano Research 2024年第9期17卷 7945-7956页

作者： Ting Li Zhen-Yu Zhang De-Cun Luo Bo-Yu Xu Rong-Jiang Zhang Ji-Long Yao Dan Li Tao xie institute of Industrial Catalysis School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049China

Solar-driven photo-thermal catalytic CO_(2)methanation reaction is a promising technology to alleviate the problems posed by greenhouse gases ***,designing advanced photo-thermal catalysts remains a research challenge for CO_(2)methanation *** this work,a series of ABO3(A=lanthanide,B=transition metal)perovskite catalysts with Ce-substituted LaNiO3(La_(1-x)Ce_(x)NiO_(3),x=0,0.2,0.5,0.8,1)were synthesized for CO_(2)*** La_(0.2)Ce_(0.8)NiO_(3) exhibited the highest CH_(4) formation rate of 258.9 mmol·g^(-1)·hcat-1,CO_(2)conversion of 55.4%and 97.2%CH_(4) selectivity at 300℃with the light intensity of 2.9 W·cm^(-2).Then the catalysts were thoroughly analyzed by physicochemical structure and optical properties *** partial substitution of the A-site provided more active sites for the adsorption and activation of CO_(2)/H_(2).The sources of the active sites were considered to be the oxygen vacancies(O_(v))created by lattice distortions due to different species of ions(La^(3+),Ce^(4+),Ce^(3+))and exsolved Ni0 by H_(2)*** catalysts have excellent light absorption absorbance and low electron-hole(e^(-)/h^(+))recombination rate,which greatly contribute to the excellent performance in photo-thermal synergistic catalysis(PTC)CO_(2)*** results of in situ irradiated electron paramagnetic resonance spectrometer(ISI-EPR)and ISI-X-ray photoelectron spectroscopy(XPS)indicated that the aggregation of unpaired electrons near the defects and Ni metal(from La and Ce ions to Ov and Ni0)accelerated adsorption and activation of CO_(2)/H_(2).At last,the catalyst properties and structure were correlated with the proposed reaction mechanism from the in situ diffuse reflection infrared Fourier transform spectrum(DRIFTS)*** in situ precipitation of the B-site enhanced the dispersion of Ni,while its enriched photoelectrons upon illumination further promote hydrogen *** H^(*)spillover accelerated t

关键词： photo-thermal catalysis CO_(2)methanation perovskite A-site substitution in situ diffuse reflection infrared Fourier transform spectrum(DRIFTS)

The enhanced mechanical properties of SiC nanowires/Ba_(0.75)Sr_(0.25)Al_(2)Si_(2)O_(8) ceramics with embedded SiO_(2) interface

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Journal of Advanced Ceramics 2024年第7期13卷 933-941页

作者： xin Li xiaomeng Fan Haojie Luo xiaoke Lu Jimei Xue Fang Ye Yongsheng Liu Science and technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China Frontier institute of Science and technology Xi’an Jiaotong UniversityXi’an 710049China

In this work,low-softening-temperature and low-modulus SiO_(2) was introduced as an embedded interface between SiC nanowires(SiCnws)and a Ba_(x)Sr_(1−x)Al_(2)Si_(2)O_(8) ceramic matrix to enhance strength and toughness of the *** the sintering process,molten SiO_(2) enhances the flowability of the ceramic powders and modifies the dispersion of *** strengthening effect of SiCnws was fully realized,and the flexural strength of the optimized ceramics reached 193±16 MPa,which represents an increase of 52.6%.After the formation of the embedded SiO_(2) interface with a low modulus,cracks can deflect along the SiCnws surface,which is consistent with the criterion of He and *** can effectively extend the crack propagation path,and the fracture toughness(K_(IC))is thus improved by 94.0%,reaching 3.1±0.5 MPa·m^(1/2).

关键词： multiphase ceramics SiO_(2) interface densification mechanical properties

Surface Deposition of Ni(OH)_(2) and Lattice Distortion Induce the Electrochromic Performance Decay of NiO Films in Alkaline Electrolyte

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Energy & Environmental Materials 2024年第3期7卷 257-267页

作者： Kejun Xu Liuying Wang Chaoqun Ge Long Wang Bin Wang Zhuo Wang Chuanwei Zhang Gu Liu xi'an Research institute of High technology Xi'an 710025China School of Material Science and Engineering Zhengzhou UniversityZhengzhou 450001China School of Mechanical Engineering Xi'an University of Science and TechnologyXi'an 710054China

NiO,an anodic electrochromic material,has applications in energy-saving windows,intelligent displays,and military ***,its electrochromic mechanism and reasons for its performance degradation in alkaline aqueous electrolytes are complex and poorly understood,making it challenging to improve NiO thin *** studied the phases and electrochemical characteristics of NiO films in different states(initial,colored,bleached and after 8000 cycles)and identified three main reasons for performance ***,Ni(OH)_(2)is generated during electrochromic cycling and deposited on the NiO film surface,gradually yielding a NiO@Ni(OH)_(2)core-shell structure,isolating the internal NiO film from the electrolyte,and preventing ion ***,the core-shell structure causes the mode of electrical conduction to change from first-to second-order conduction,reducing the efficiency of ion transfer to the surface Ni(OH)_(2)***,Ni(OH)_(2)and NiOOH,which have similar crystal structures but different b-axis lattice parameters,are formed during electrochromic cycling,and large volume changes in the unit cell reduce the structural stability of the thin ***,we clarified the mechanism of electrochromic performance degradation of NiO films in alkaline aqueous electrolytes and provide a route to activation of NiO films,which will promote the development of electrochromic technology.

关键词： alkaline electrolyte electrochromism NiO film performance attenuation mechanism

Social Robot Detection Method with Improved Graph Neural Networks

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Computers, Materials & Continua 2024年第2期78卷 1773-1795页

作者： Zhenhua Yu Liangxue Bai Ou Ye Xuya Cong institute of Systems Security and Control College of Computer Science and TechnologyXi’an University of Science and TechnologyXi’an710054China

Social robot accounts controlled by artificial intelligence or humans are active in social networks,bringing negative impacts to network security and social *** social robot detection methods based on graph neural networks suffer from the problem of many social network nodes and complex relationships,which makes it difficult to accurately describe the difference between the topological relations of nodes,resulting in low detection accuracy of social *** paper proposes a social robot detection method with the use of an improved neural ***,social relationship subgraphs are constructed by leveraging the user’s social network to disentangle intricate social relationships ***,a linear modulated graph attention residual network model is devised to extract the node and network topology features of the social relation subgraph,thereby generating comprehensive social relation subgraph features,and the feature-wise linear modulation module of the model can better learn the differences between the ***,user text content and behavioral gene sequences are extracted to construct social behavioral features combined with the social relationship subgraph ***,social robots can be more accurately identified by combining user behavioral and relationship *** carrying out experimental studies based on the publicly available datasets TwiBot-20 and Cresci-15,the suggested method’s detection accuracies can achieve 86.73%and 97.86%,*** with the existing mainstream approaches,the accuracy of the proposed method is 2.2%and 1.35%higher on the two *** results show that the method proposed in this paper can effectively detect social robots and maintain a healthy ecological environment of social networks.

关键词： Social robot detection social relationship subgraph graph attention network feature linear modulation behavioral gene sequences

In-situ coupling construction of interface bridge to enhance electrochemical stability of all solid-state lithium metal batteries

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Journal of Energy Chemistry 2024年第2期89卷 18-26,I0003页

作者： Qianwei Zhang Rong Yang Chao Li Lei Mao Bohai Wang Meng Luo Yinglin Yan Yiming Zou Lisheng Zhong Yunhua Xu International Research Center for Composite and Intelligent Manufacturing technology Institute of Chemical Power SourcesXi’an University of TechnologyXi’an 710048ShaanxiChina School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048ShaanxiChina School of Electrical Engineering Xi’an University of TechnologyXi’an 710048ShaanxiChina Yulin University Yulin 719000ShaanxiChina

Polymer-based composite electrolytes composed of three-dimensional Li_(6.4)La_(3)Zr_(2)Al_(0.2)O_(12)(3D-LLZAO)have attracted increasing attention due to their continuous ion conduction and satisfactory mechanical ***,the organic/inorganic interface is incompatible,resulting in slow lithium-ion transport at the ***,the compatibility of organic/inorganic interface is an urgent problem to be *** by the concept of“gecko eaves”,polymer-based composite solid electrolytes with dense interface structures were *** bridging of organic/inorganic interfaces was established by introducing silane coupling agent(3-chloropropyl)trimethoxysilane(CTMS)into the PEO-3D-LLZAO(PL)*** in-situ coupling reaction improves the interface affinity,strengthens the organic/inorganic interaction,reduces the interface resistance,and thus achieves an efficient interface ion transport *** prepared PEO-3D-LLZAO-CTMS(PLC)electrolyte exhibits enhanced ionic conductivity of 6.04×10^(-4)S cm^(-1)and high ion migration number(0.61)at 60℃and broadens the electrochemical window(5.1 V).At the same time,the PLC electrolyte has good thermal stability and high mechanical ***,the Li Fe PO_(4)|PLC|Li battery has excellent rate performance and cycling stability with a capacity decay rate of 2.2%after 100 cycles at 60℃and 0.1 *** advantages of PLC membranes indicate that this design approach is indeed practical,and the in-situ coupling method provides a new approach to address interface compatibility issues.

关键词： Organic/inorganic interphase Coupling effect Composite electrolyte Interface compatibility