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Results in Engineering 2025年 26卷

作者： Liao, Dongjie Lou, Wenzhong Feng, Hengzhen Kan, Wenxing Li, Zhipeng Lu, Yi School of Mechatronical Engineering Beijing Institute of Technology Beijing100081 China Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing100081 China

Micro pyrotechnic train is an energetic microsystem that integrates MEMS control circuits, micro energetic devices, micro safety mechanisms, and micro output charges. It has been actively promoted and applied in space technology, healthcare, and ordnance due to its outstanding advantages of miniaturization, high efficiency, and intelligence. Micro pyrotechnic train mainly achieves functions such as ignition, propulsion, or detonation through the energetic materials filled inside it. As the core of micro pyrotechnic trains, energetic materials and their development have always been a highly concerned subject. Herein, this paper analyzes and summarizes the research progress of advanced energetic materials, such as two-dimensional energetic materials, metastable intermolecular composites and green primary explosives. Moreover, the application of additive manufacturing technology and in-situ synthesis methods (gas-solid phase chemical reactions, electrically assisted chemical reactions) in the preparation of advanced energetic materials was discussed. Furthermore, suggestions regarding the possible future research directions are proposed. © 2025 The Author(s)

关键词： Detonation

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V-band antipolar fin line microstrip waveguide conversion structure 13

V-band antipolar fin line microstrip waveguide conversion st...

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13th International Symposium on Antennas, Propagation and EM Theory, ISAPE 2021

作者： Chen, Wei Wen, Rui-Hu Zheng, Xiao-Yan Liu, Shui-Ying Niu, Lan-Jie Science and Technology on Electromechanical Dynamic Control Laboratory Xi'an710065 China

ISBN: (纸本)9781665418126

The V-band microstrip waveguide conversion structure cannot meet the requirements of simple installation and integrated design. The fin line structure with specific size and shape is etched on the surface of the film. By adjusting the parameters of the opposite pole fin line, the conversion structure can meet the requirements of practical performance. The test results show that the center frequency of antipolar fin line microstrip waveguide conversion structure is 71.6GHz, the internal reflection parameter S11 is less than -20dB in the bandwidth of 67.3-77.0GHz and 10GHz, and the conversion structure size is 6.56mm*1.47mm*0.127mm. The conversion structure is installed in the middle of the V-band waveguide along the E-plane of the waveguide, without slotting the waveguide wall, which meets the requirements of superior performance, simple installation and integrated design. © 2021 IEEE.

关键词： Fins (heat exchange)

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Research on a fuze anti-jamming strategy under the background of complex ground objects 13

Research on a fuze anti-jamming strategy under the backgroun...

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13th International Symposium on Antennas, Propagation and EM Theory, ISAPE 2021

作者： Xia, Lei Dai, Liang Zou, Jin-Long Science and Technology on Electromechanical Dynamic Control Laboratory Xi'an710065 China

ISBN: (纸本)9781665418126

Aiming at the problem of the reduced reliability of the radio proximity fuze under the jamming of complex ground objects,a method of fixed height for laser and radio combined detection is proposed. Using the method of dual-beam separate airspace detection and information fusion,a mathematical model of the fuze's fixed height initiation is established. Through the analysis of the dynamic ground detection model and the ground objects jamming detection model, this design idea and mathematical model against the ground objects jamming effectiveness are confirmed. © 2021 IEEE.

关键词： Object detection

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Elastic wave propagation and attenuation characteristics of roof fracture source

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Geomechanics and Engineering 2025年第4期40卷 295-305页

作者： Zhang, Peng-Fei Zhao, Tong-Bin Gong, Xu-Fei Tan, Yan Guo, Chuan-Qing College of Energy and Mining Engineering Shandong University of Science and Technology Qingdao266590 China State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology Shandong University of Science and Technology Qingdao266590 China Shandong Key Laboratory of Intelligent Prevention and Control of Dynamic Disaster in Deep Mines Shandong University of Science and Technology Qingdao266590 China Energy Group Co. Ltd. Jining No.2 Coal Mine Jining272012 China

Abstract. The propagation attenuation law of elastic waves generated by rock mass fractures in strata is of great significance in explaining engineering problems, such as rock bursts. In this study, a wave velocity model was established based on the actual stratum conditions of the Jining No.2 coal mine in China. The propagation process of different types of elastic waves is simulated using the elastic wave equation and finite difference method. The attenuation coefficients of various elastic wave parameters propagating at different positions were calculated. Based on the calculated results, an attenuation equation for the elastic wave energy is proposed. The results show that the propagation of S-waves and P-waves in strata is similar to each other, and wave pattern transformation occurs at the interface of the strata. The magmatic rocks played a role in channeling and reflecting elastic wave propagation, leading to the occurrence of low-energy aftershocks in the coal seams. The peak displacement, peak stress, and energy density of the elastic wave that propagated to the coal seam after the siltstone layer fracture of the roof of the 3down coal seam decreased to 28%, 25%, and 9% of the source, respectively. The attenuation of elastic wave energy is highly correlated with the propagation distance, and the attenuation equation can be represented as an exponential function. These results are of great significance for revealing the propagation attenuation process of elastic waves in the stratum. © 2025 Techno-Press, Ltd.

关键词： Exponential functions

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Tunable Chirality and Helicity of Bessel Twisted Beams Near the Dirac Points in Topological Metacrystal

Tunable Chirality and Helicity of Bessel Twisted Beams Near ...

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International Symposium on Antennas, Propagation and EM Theory (ISAPE)

作者： Yuanfei Hui Zhiwei Cui Sihan Zhao Tie Li Gang Li Haijun He Science and Technology on Electromechanical Dynamic Control Laboratory Xi'an China School of Physics Xidian University Xi'an China

ISBN: (数字)9798350353129

ISBN: (纸本)9798350353136

In this work, we undertake an approach to describe the tunable optical chirality and helicity of twisted beam near the Dirac point in topological meta-crystals. An improved method based on the full vector wave analysis is introduced to investigate the chirality and helicity of Bessel twisted beams near the Dirac point in the interface of topological meta-crystals. It is showed that the giant non-specular effects of chirality and helicity are discovered when a Bessel twisted Beam reflects in the vicinity of a Dirac point, which is sensitive to the incident frequency, angle, and electromagnetic properties of the topological meta-crystal. We can attribute the giant non-specular effect of chirality and helicity to the degeneracy between critical angle and Brewster angle caused by the Dirac point. The results will be of significant interest of study the measurement of Dirac point, and inspire a perspective for manipulating twisted beams with Dirac point.

关键词： Analytical models Antenna theory Beams Vectors Metamaterials Optical sensors Optical reflection Electromagnetic fields Electromagnetics Photonics

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Structural and optical characteristics of InAs0.02Sb0.82N0.16thick epilayers grown by melt epitaxy

Structural and optical characteristics of InAs0.02Sb0.82N0.1...

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2023 Advanced Fiber Laser Conference, AFL 2023

作者： Gao, Yuzhu Chen, Zun Tian Hayakawa, Yasuhiro College of Electronics and Information Engineering Tongji University Shanghai201804 China Science and Technology on Electromechanical Dynamic Control Laboratory Xian710061 China Research Institute of Electronics Shizuoka University Johoku 3-5-1 Hamamatsu432-8011 Japan

ISBN: (纸本)9781510677661

InAs0.02Sb0.82N0.16 thick epilayers have been grown on InAs substrates by melt epitaxy (ME) technology. Fourier transform infrared (FTIR) transmission spectra showed that the cutoff wavelength of InAs0.02Sb0.82N0.16 samples grown by ME is 10.0 μm indicating the band gap narrowing. The thickness of the epilayers grown by ME observed by scanning electron microscopy (SEM) reaches 183 μm. X-ray diffraction (XRD) measurements confirmed that the epilayers are single crystals. The full-width at half-maximum (FWHM) of InAs0.02Sb0.82N0.16 (400) CuKα1 diffraction peak is 298.8 arcsec. The high quality of the crystals benefits from the thickness of the epilayers exceeding 100 μm, which significantly suppresses the effect of the lattice mismatch between InAs0.02Sb0.82N0.16 epilayers and InAs substrates. Energy dispersive spectrometer (EDS) attached SEM measurements revealed that 16% nitrogen has been incorporated in the epilayers. © COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.

关键词： III-V semiconductors

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Unsupervised Feature Selection with self-Weighted and 2,0-Norm Constraint 48

Unsupervised Feature Selection with self-Weighted and 2,0-No...

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48th IEEE International Conference on Acoustics, Speech and Signal Processing, ICASSP 2023

作者： Yuan, Yongjin Wang, Zheng Nie, Feiping Li, Xuelong Northwestern Polytechnical University School of Computer Science Xi'an710072 China Xi'an710072 China Science and Technology on Electromechanical Dynamic Control Laboratory China Ministry of Industry and Information Technology Key Laboratory of Intelligent Interaction and Applications Northwestern Polytechnical University Xi'an710072 China

ISBN: (纸本)9781728163277

At data mining field, it is a fundamental problem to dispose of high-dimensional data. Many existing unsupervised methods select features by manifold learning or exploring spectral analysis, thus preserving the intrinsic structure of raw data. But most of them follow an assumption that all features are equally importance. To settle this problem, we draw a novel feature selection module that simultaneously performs learning of feature weights matrix, similarity graph structure and projection matrix, so that the local structure after feature weighting and subspace sparse projection is received. Finally, we solve the model based on 2,0-norm directly by an iterative optimization algorithm and demonstrate the feasibility and effectiveness of our approach via extensive experiments. © 2023 IEEE.

关键词： Feature Selection

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A X/Ka-Band Low-Profile Double-Conical-Beams Antenna with Vortex Electromagnetic Waves

A X/Ka-Band Low-Profile Double-Conical-Beams Antenna with Vo...

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IEEE International Wireless Symposium (IWS)

作者： Dongjie Qin Weishan Li Jie Ma Yiping Zang Xu Zhao Xi'an Institute of Electromechanical Information Technology Xi'an China Science and Technology on Electromechanical Dynamic Control Laboratory Xi'an China

Antennas with conical beams have the advantage in anti-interference applications. This paper proposes a low-profile antenna with two conical beams working at X and Ka bands. To save space, a Ka-band multi-ring antenna composed of one circular plate and five concentric rings is placed on the center of an X-band uniform circular array (UCA) antenna formed by eight microstrip patches. A vortex electromagnetic wave (VEW) with mode 1 is generated with the UCA antenna with phase difference of the elements of 45 deg. With different phase difference, the higher modes of the VEW can be formed. The cylindrical cavity not only serves as the cavity of the Ka-band antenna, but also physically separates the two antennas which makes them do not interference with each other. The peak gain at 37.5GHz of Ka band is 12.4dBi, and the 3dB beamwidth is in the range of 6.9-24.4deg. The peak gain at 10GHz of X band is 8.2dBi, and the 3dB beamwidth is in the range of 12.8-43deg.

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A Symmetry Treatment in Cylindrical Explicit and Unconditionally Stable FDTD Method

A Symmetry Treatment in Cylindrical Explicit and Uncondition...

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International Symposium on Antennas, Propagation and EM Theory (ISAPE)

作者： Sihan Zhao Bing Wei Yuanfei Hui Tie Li Gang Li Tiantian Feng Science and Technology on Electromechanical Dynamic Control Laboratory Xi'an China School of Physics Xidian University Xi'an China

ISBN: (数字)9798350353129

ISBN: (纸本)9798350353136

A symmetry treatment in cylindrical explicit and unconditionally stable FDTD (CEUS-FDTD) method is given. The system matrix of CEUS-FDTD method is unsymmetric, which will render instability since the explicit central–difference scheme is used for temporal discretization. By splitting the grid matrix reasonably and modifying the corresponding coefficients, the system matrix is transformed into a new symmetric matrix compulsively. Then an additional diagonal matrix will be obtained naturally on the other side of the equation to ensure that the time marching equation still holds. At last, unstable modes could be obtained by solving generalized eigenvalue problem of the new symmetric system matrix with respect to the diagonal matrix. Numerical results illustrates that the stability of CEUS-FDTD could be ensured and the accuracy would not be affected.

关键词： Symmetric matrices Accuracy Antenna theory Power system stability Eigenvalues and eigenfunctions Time-domain analysis Numerical stability Finite difference methods

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Research on a projectile-borne measuring apparatus for electromagnetic launcher 4

Research on a projectile-borne measuring apparatus for elect...

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4th International Conference on Mechanical, Electric and Industrial Engineering, MEIE 2021

作者： Cao, Ronggang Hu, Xueyi Dong, Erwa Ma, Xiao Zhou, Yu Science and Technology on Electromechanical Dynamic Control Laboratory Beijing Institute of Technology Beijing China

In order to evaluate the electromagnetic launch effectiveness and understand the corrosion damage of the electromagnetic launcher, it is necessary to master the magnetic field data in the bore. At present, there is no related research on the measurement of the bore magnetic field of the electromagnetic launcher. Therefore, a small-scale projectile-borne measuring apparatus based on B-dot probe is developed in this paper. This apparatus uses FPGA as the core. Through the static magnetic field measurement experiment, the data of the induced voltage and the induced magnetic field can be obtained. The projectile-borne magnetic field measuring apparatus designed in this paper can accurately measure the bore magnetic field of the electromagnetic launcher, which lays the foundation for further analysis of the influence of the electromagnetic field in the bore on the launch effect and investigation of the corrosion damage of the electromagnetic launcher. © Published under licence by IOP Publishing Ltd.

关键词： Projectiles

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