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Rare Metals 2022年第4期41卷 1380-1384页

作者： zhen-dong Wang zhen-Quan Lai Department of Physics Nanchang UniversityNanchang 330031China

Single(200)-oriented TiN thin films were deposited on quartz substrate by direct current(DC) magnetron reactive sputtering process at a wide range of substrate temperature from 200 to 600 ℃.The effects of sputtering pressure and substrate temperature on the crystalline nature,morphology,electrical and optical properties of the deposited thin films were analyzed by X-ray diffraction(XRD),atomic force microscopy(AFM),four-point resistivity test system and ultraviolet visible near-infrared(UV-Vis-NIR) spectroscopy,*** results show that single(200)-oriented TiN thin films can be obtained at a wide range of substrate temperature from 200 to 600 ℃ with the grain size increasing from 35.9 to 64.5 *** resistivity of the product is as low as95 μΩ·cm,and the value of the optical reflectance is above68 % in the near-infrared(NIR) range of 760-1500 nm.

关键词： TiN thin film DC magnetron reactive sputtering Crystal orientation Optical property

Progress and perspectives of point cloud intelligence

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Geo-Spatial Information Science 2023年第2期26卷 189-205页

作者： Bisheng Yang Nobert Haala zhen dong State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhanChina Institute for Photogrammetry Stuttgart UniversityStuttgartGermany

With the rapid development of reality capture methods,such as laser scanning and oblique photogrammetry,point cloud data have become the third most important data source,after vector maps and *** cloud data also play an increasingly important role in scientific research and engineering in the fields of Earth science,spatial cognition,and smart ***,how to acquire high-quality three-dimensional(3D)geospatial information from point clouds has become a scientific frontier,for which there is an urgent demand in the fields of surveying and mapping,as well as geoscience *** address the challenges mentioned above,point cloud intelligence came into *** paper summarizes the state-of-the-art of point cloud intelligence,with regard to acquisition equipment,intelligent processing,scientific research,and engineering *** this purpose,we refer to a recent project on the hybrid georeferencing of images and LiDAR data for high-quality point cloud collection,as well as a current benchmark for the semantic segmentation of high-resolution 3D point *** projects were conducted at the Institute for Photogrammetry,the University of Stuttgart,which was initially headed by the late ***,the development prospects of point cloud intelligence are summarized.

关键词： Point cloud big data point cloud intelligence semantic labeling structured modeling machine learning

Fusion of Spiral Convolution-LSTM for Intrusion Detection Modeling

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Computers, Materials & Continua 2024年第5期79卷 2315-2329页

作者： Fei Wang zhen dong School of Cyberspace Security Gansu University of Political Science and LawLanzhou73000China

Aiming at the problems of low accuracy and slow convergence speed of current intrusion detection models,SpiralConvolution is combined with Long Short-Term Memory Network to construct a new intrusion detection *** dataset is first preprocessed using solo thermal encoding and normalization *** the spiral convolution-Long Short-Term Memory Network model is constructed,which consists of spiral convolution,a two-layer long short-term memory network,and a *** is shown through experiments that the model is characterized by high accuracy,small model computation,and fast convergence speed relative to previous deep learning *** model uses a new neural network to achieve fast and accurate network traffic intrusion *** model in this paper achieves 0.9706 and 0.8432 accuracy rates on the NSL-KDD dataset and the UNSWNB-15 dataset under five classifications and ten classes,respectively.

关键词： Intrusion detection deep learning spiral convolution long and short term memory networks 1D-spiral convolution

Corrosion behavior of additive-manufactured NiFeCrMo alloys in various corrosion media

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Journal of Iron and Steel Research International 2023年第8期30卷 1574-1585页

作者： dong-peng Wang Shuai Wang zhen Chen Xing-cheng Xie zhen-zhen dong Hong-zhou dong Yi-cheng Wu zhen-guang Liu Wei-li Li Yu-xin Wang School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuChina GRIMAT Engineering Institute Co. Ltd.Beijing 101407China GRINM(Guangdong)Institute for New Advanced Materials and Technology Dongguan 528041GuangdongChina School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuChina

To understand the corrosion performance of additive-manufactured Ni-based in various corrosion media during the actual engineering application environment,the corrosion properties of NiFeCrMo alloys were investigated in 3.5 wt.%NaCl solution,1 mol/L H2SO_(4) solution,and 1 mol/L KOH solution,using potentiodynamic polarization and electrochemical impedance *** electrochemical measurement results revealed that the additive-manufactured NiFeCrMo alloys have higher corrosion resistance in all three solutions,compared with the as-cast *** results of the scanning electron microscope confirmed that the degree of additive-manufactured NiFeCrMo alloys after potentiostatic polarization in all three solutions is less serious.X-ray photoelectron spectroscopy analysis revealed that the enhancement of the corrosion resistance for the additive-manufactured NiFeCrMo alloys is attributed to the modification of the composition of the passive *** manufactured processing promotes the enrichment of the element of Cr or Mo in the passive film and it suppresses the formation of the oxidation of the element of Fe,leading to higher stability of the passive *** reason for the higher corrosion resistance of the additive-manufactured NiFeCrMo alloys was related to the enrichment of the element of Cr,as well as the lower content of the elements of Ni and Fe near the grain boundaries,which are beneficial to forming a more compact passive *** combined results are essential for the applications of high-strength Ni-based as structural materials in a corrosion environment.

关键词： Ni-based alloy Additive manufacturing Corrosion Passive film Corrosion media

A Biomimetic Study of Discontinuous-Constraint Metamorphic Mechanism for Gecko-Like Robot

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Journal of Bionic Engineering 2007年第2期4卷 91-95页

作者： zhen-dong Dai Jiu-rong Sun Institute of Bio-inspired Structure and Surface Engineering The Academy of Frontier Science Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China College of Life Sciences Peking University Beijing 100871 P. R. China

Locomotion ability, efficiency and reliability are key targets for a good robot. The linkage mechanism for robot locomotion is a discontinuous-constraint metamorphic mechanism. Here we set up equations to present the discontinuous-constraint, point out that driving and controlling are the key points to improve the performance and efficiency of the linkage mechanism. Inspired by controlling strategy of the motor nervous system in peripheral vertebrae to the locomotion, we draw off motor control and drive strategy.

关键词： biomimetic robotics gecko-like robot metamorphic mechanism

Manufacture and Performance of Ionic Polymer-Metal Composites

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Journal of Bionic Engineering 2007年第3期4卷 143-149页

作者： Min Yu Hui Shen zhen-dong Dai Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China

Ion-exchange Polymer Metal Composites （IPMC） are a new class of intelligent material that can be used effectively as actuators and artificial muscles. IPMC was fabricated and its displacement and force characteristics were investigated with respect to voltage, frequency and waveform of the controlling signal. A square waveform input generated slightly larger displacement and force than sinusoidal or triangular waveform. When the voltage was increased and the frequency was decreased, displacement and force were both increased. However, although the bending deformation of IPMC was large, the output force was much lower than we expected. Improvement of the force output is key and is the main obstacle to be overcome in order to make IPMC of practical use.

关键词： IPMC artificial muscle

An integrative synchronization and imaging algorithm for GNSS-based BSAR

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Science China(Information Sciences) 2015年第6期58卷 53-67页

作者： ZHANG QiLei CHANG WenGe ZENG ZhangFan dong zhen College of Electronic Science and Engineering National University of Defense Technology School of Electronic Electrical and Computer Engineering University of Birmingham

In this paper, we develop an integrative synchronization and imaging algorithm for bistatic synthetic aperture radar(BSAR) using Global Navigation Satellite Systems as transmitters and a fixed receiver. Due to the lack of a dedicated synchronization link, the usage of navigation signals and the system complexity,traditional synchronization and imaging solutions are not applicable for GNSS-based BSAR. To resolve this problem, this paper focuses on the integrative signal processing algorithm for GNSS-based BSAR. Firstly, to remove the effect of navigation signals, synchronization pre-processing is developed. Then the principle of measuring errors neutralization is theoretically proved by considering the geometric peculiarity of the *** on this principle, an integrative synchronization and imaging algorithm is proposed. Finally, the validity of the developed algorithm is confirmed by experimentally obtained data.

关键词： bistatic synthetic aperture radar(BSAR) GNSS-based BSAR synchronization imaging forma-tion GNSS

L-band geosynchronous SAR imaging degradations imposed by ionospheric irregularities

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Science China(Information Sciences) 2017年第6期60卷 103-115页

作者： Yifei JI Qilei ZHANG Yongsheng ZHANG zhen dong College of Electronic Science and Engineering National University of Defense Technology

It is well known that the ionospheric scintillation caused by small-scale ionospheric irregularities is a major distortion source for low-frequency spaceborne synthetic aperture radar(SAR) imaging. For L-band geosynchronous earth orbit(GEO) SAR, the orbit height is ultra-high and the integration time is ultra-long,thus ionospheric irregularities may cause more significant distortions on the imaging focusing. To evaluate this effect, the generalized ambiguity function(GAF) is employed to establish the analytical model. The imaging resolution can be studied by calculating the second moment of GAF. Furthermore, since the scanning velocity of the ionospheric penetration point(IPP) for GEO SAR is much slower than that of low earth orbit(LEO)SAR, the convection velocity of the ionospheric irregularities is no longer negligible. Taking this into account,we derive a more accurate expression of ionospheric irregularities' effect. The theoretical derivation is validated by numerical analyses and signal-level simulations.

关键词： ionospheric irregularities L-band GEO SAR generalized ambiguity function imaging resolution convection velocity

Double-stranded DNA-nucleic acid dye complex-sensitized biocatalytic photosynthesis:Base pairing-switched regeneration of nicotinamide cofactor

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Journal of Energy Chemistry 2024年第7期94卷 618-624页

作者： zhen dong Yanying Wang Dan Li Peng Wu College of Chemistry Sichuan UniversityChengdu 610064SichuanChina Analytical&Testing Centre State Key Laboratory of Hydraulics and Mountain River EngineeringSichuan UniversityChengdu 610064SichuanChina School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007HenanChina

Photo-biocatalysis,the combination of photosensitization and biocatalysis,is an emerging solution for sunlight-based renewable *** is thus important to develop light antennas with both good light har-vesting and efficient electron ***,the intriguing electrical conductivity of dsDNA and its host effect(for nucleic acid dyes to harvest light)were explored simultaneously to develop a dsDNA-based light antenna for *** SYBR Green I(SG)as the example of the nucleic acid dye,the proposed SG-dsDNA system was found to be capable for visible-light-driven reduced nicotinamide adenine dinucleotide(NADH)regeneration,and the turnover frequency of which(1.35 min^(-1))exceeded most of the existing photocatalytic *** SG can only be hosted by dsDNA,meanwhile dsDNA can be formed through hybridization between single strand DNA and its complementary strand,the pro-posed system adds an extra control of the photocatalytic activity(DNA base pairing-based switch).When integrating the SG-dsDNA system with NADH-dependent horse liver alcohol dehydrogenase(HLADH),successful synthesis of 2-phenylpropanol(a crucial intermediates of profens manufacturing)was achieved.

关键词： Photosynthesis dsDNA SYBRGreenI TICT 2-phenylpropanol

Analytical Solution for the Transient Response of A Sloping Seabed Induced by A P-Wave Line Source

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China Ocean Engineering 2023年第6期37卷 1044-1054页

作者： MA Rong SHAN zhen-dong XIE Zhi-nan dong Rui JING Li-ping Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationHarbin 150080China Key Laboratory of Earthquake Disaster Mitigation Ministry of Emergency ManagementHarbin 150080China

Many offshore marine structures are built on the seabed that are slightly or considerably *** study the sloping seabed transient response during marine earthquakes,an analytical solution induced by a P-wave line source embedded in the solid is *** the derivation,the wave fields in the fluid layer and the semi-infinite solid are firstly constructed by using the generalized ray method and the fluid-solid interface reflection and transmission ***,the analytical solution in the transformed domain is obtained by superposing these wave fields,and the analytical solution in the time domain by applying the analytical inverse Laplace transform *** the head wave generation conditions and arrival times at the fluid-solid interface are derived through this *** the use of numerical examples,the analytical solution is proved right and the impacts of the sloping angle on the hydrodynamic pressure in the sea,the seismic wave propagation in the seabed,the head wave,and the Scholte wave at the seawater-seabed interface are also addressed.

关键词： marine earthquake seismic wave head wave Scholte wave sloping seabed