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Phase Patterning of Poly(oxime-ester)for Information Encryption by Photo-induced Isomerization
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作者 Yu-Fan Yang Yun Bai +1 位作者 Yi-Bao Li Chang-Fei He 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第10期1488-1494,I0010,共8页
Crystal polymers or liquid crystal elastomers undergo a phase transition that results in a change in the corresponding optical properties,which has the potential to be applied in areas such as information encryption a... Crystal polymers or liquid crystal elastomers undergo a phase transition that results in a change in the corresponding optical properties,which has the potential to be applied in areas such as information encryption and anti-counterfeiting.The utilization of these materials for patterning purposes requires different phase transition temperatures.However,once prepared,altering the phase transition temperature of them presents significant challenges.Herein,a poly(oxime-ester)(POE)network is developed to achieve high-resolution and multilevel patterning by photo-induced isomerization.The as-prepared POE exhibits the ability to transition from an opaque state to a transparent state under temperature stimuli,with the transition temperature and kinetics dependent on UV light exposure time.Thus,complex patterns and information can be encrypted through different selective regional exposure time and decrypted under specific temperature or cooling time.Furthermore,we illustrate an example of temporal communication,where cooling time or temperature serves as the encoded information.This research expands the application scope of advanced encryption materials,showcasing the potential of POE in dynamic information encryption and decryption processes. 展开更多
关键词 Poly(oxime-ester) ISOMERIZATION phase patterning Information encryption
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TWO-PHASE FLOW PATTERNS IN A 90° BEND AT MICROGRAVITY 被引量:2
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作者 赵建福 K.S.GABRIEL 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2004年第3期206-211,共6页
Bends are widely used in pipelines carrying single-and two-phase fluids in both ground and space applications.In particular,they play more important role in space applications due to the extreme spatial constraints.In... Bends are widely used in pipelines carrying single-and two-phase fluids in both ground and space applications.In particular,they play more important role in space applications due to the extreme spatial constraints.In the present study,a set of experimental data of two-phase flow patterns and their transitions in a 90°bend with inner diameter of 12.7 mm and curvature radius of 76.5 mm at microgravity conditions are reported.Gas and liquid superficial velocities are found to range from (1.0~23.6)m/s for gas and(0.09~0.5)m/s for liquid,respectively.Three major flow patterns, namely slug,slug-annular transitional,and annular flows,are observed in this study.Focusing on the differences between flow patterns in bends and their counterparts in straight pipes,detailed analyses of their characteristics are made.The transitions between adjoining flow patterns are found to be more or less the same as those in straight pipes,and can be predicted using Weber number models satisfactorily. The reasons for such agreement are carefully examined. 展开更多
关键词 two-phase flow flow patterns 90°bend MICROGRAVITY
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A numerical study on pattern selection in crystal growth by using anisotropic lattice Boltzmann-phase field method 被引量:1
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作者 Zhaodong Zhang Yuting Cao +3 位作者 Dongke Sun Hui Xing Jincheng Wang Zhonghua Ni 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第2期446-457,共12页
Pattern selection during crystal growth is studied by using the anisotropic lattice Boltzmann-phase field model.In the model,the phase transition,melt flows,and heat transfer are coupled and mathematically described b... Pattern selection during crystal growth is studied by using the anisotropic lattice Boltzmann-phase field model.In the model,the phase transition,melt flows,and heat transfer are coupled and mathematically described by using the lattice Boltzmann(LB)scheme.The anisotropic streaming-relaxation operation fitting into the LB framework is implemented to model interface advancing with various preferred orientations.Crystal pattern evolutions are then numerically investigated in the conditions of with and without melt flows.It is found that melt flows can significantly influence heat transfer,crystal growth behavior,and phase distributions.The crystal morphological transition from dendrite,seaweed to cauliflower-like patterns occurs with the increase of undercoolings.The interface normal angles and curvature distributions are proposed to quantitatively characterize crystal patterns.The results demonstrate that the distributions are corresponding to crystal morphological features,and they can be therefore used to describe the evolution of crystal patterns in a quantitative way. 展开更多
关键词 LATTICE BOLTZMANN crystal growth phase field MELT flow pattern selection
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PATTERN RECOGNITION APLLIED TO STABILITY OF FILLED Ti_2Ni PHASES
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作者 ZHOU Diangen CHEN Nianyi Shanghai Institute of Metallurgy,Academia Sinica,Shanghai,China professor,Shanghai Institute of Metallurgy,Academia Sinica,Shanghai,200050,China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1993年第3期161-162,共2页
Pattern recognition method is used for the investigation of stability,region of filled Ti_2Ni phases in multi-dimensional bond-parameter space.The filling of C,N and O atoms into T_6 octahedra consisting of atoms of e... Pattern recognition method is used for the investigation of stability,region of filled Ti_2Ni phases in multi-dimensional bond-parameter space.The filling of C,N and O atoms into T_6 octahedra consisting of atoms of earhy-transition elements makes the expansion of the stability region of Ti_2Ni phase,and the relative stability of AI_2Cu and MoSi_2 type com- pounds decreases after the introduction of non-metallic elements such as C,N and O. 展开更多
关键词 filledTi_2Ni phase pattern recognition
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Low side lobe pattern synthesis using projection method with genetic algorithm for truncated cone conformal phased arrays 被引量:9
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作者 Guoqi Zeng Siyin Li +1 位作者 Yan Zhang Shanwei L 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第4期554-559,共6页
A hybrid method for synthesizing antenna's three dimensional (3D) pattern is proposed to obtain the low sidelobe feature of truncated cone conformal phased arrays. In this method, the elements of truncated cone con... A hybrid method for synthesizing antenna's three dimensional (3D) pattern is proposed to obtain the low sidelobe feature of truncated cone conformal phased arrays. In this method, the elements of truncated cone conformal phased arrays are projected to the tangent plane in one generatrix of the truncated cone. Then two dimensional (2D) Chebyshev amplitude distribution optimization is respectively used in two mutual vertical directions of the tangent plane. According to the location of the elements, the excitation current amplitude distribution of each element on the conformal structure is derived reversely, then the excitation current amplitude is further optimized by using the genetic algorithm (GA). A truncated cone problem with 8x8 elements on it, and a 3D pattern desired side lobe level (SLL) up to 35 dB, is studied. By using the hybrid method, the optimal goal is accomplished with acceptable CPU time, which indicates that this hybrid method for the low sidelobe synthesis is feasible. 展开更多
关键词 conformal phased array low side lobe pattern synthe-sis projection method genetic algorithm optimization.
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NON-LOCAL MODELING ON MACROSCOPIC DOMAIN PATTERNS IN PHASE TRANSFORMATION OF NiTi TUBES 被引量:3
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作者 Yongjun He Qingping Sun 《Acta Mechanica Solida Sinica》 SCIE EI 2009年第5期407-417,共11页
Recent experiments revealed many new phenomena of the macroscopic domain patterns in the stress-induced phase transformation of a superelastic polycrystalline NiTi tube during tensile loading. The new phenomena includ... Recent experiments revealed many new phenomena of the macroscopic domain patterns in the stress-induced phase transformation of a superelastic polycrystalline NiTi tube during tensile loading. The new phenomena include deformation instability with the formation of a helical domain, domain topology transition from helix to cylinder, domain-front branching and loading-path dependence of domain patterns. In this paper, we model the polycrystal as an elastic continuum with nonconvex strain energy and adopt the non-local strain gradient energy to account for the energy of the diffusive domain front. We simulate the equilibrium domain patterns and their evolution in the tubes under tensile loading by a non-local Finite Element Method (FEM). It is revealed that the observed loading-path dependence and topology transition of do- main patterns are due to the thermodynamic metastability of the tube system. The computation also shows that the tube-wall thickness has a significant effect on the domain patterns: with fixed material properties and interfacial energy density, a large tube-wall thickness leads to a long and slim helical domain and a severe branching of the cylindrical-domain front. 展开更多
关键词 martensitic phase transition macroscopic domain patterns NiTi polycrystalline tubes non-local and nonconvex elasticity tube-wall thickness effect metastability and instability
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Analysis on Patterns of Globally Coupled Phase Oscillators with Attractive and Repulsive Interactions
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作者 王鹏飞 阮晓东 +1 位作者 许忠斌 付新 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第11期507-514,共8页
The Hong-Strogatz(HS) model of globally coupled phase oscillators with attractive and repulsive interactions reflects the fact that each individual(oscillator) has its own attitude(attractive or repulsive) to the same... The Hong-Strogatz(HS) model of globally coupled phase oscillators with attractive and repulsive interactions reflects the fact that each individual(oscillator) has its own attitude(attractive or repulsive) to the same environment(mean Seld).Previous studies on HS model focused mainly on the stable states on Ott-Antonsen(OA)manifold.In this paper,the eigenvalues of the Jacobi matrix of each fixed point in HS model are explicitly derived,with the aim to understand the local dynamics around each fixed point.Phase transitions are described according to reJative population and coupling strength.Besides,the dynamics off OA manifold is studied. 展开更多
关键词 phase OSCILLATOR HS model pattern
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Plasticity-induced characteristic changes of pattern dynamics and the related phase transitions in small-world neuronal networks 被引量:1
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作者 黄旭辉 胡岗 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第10期609-616,共8页
Phase transitions widely exist in nature and occur when some control parameters are changed. In neural systems, their macroscopic states are represented by the activity states of neuron populations, and phase transiti... Phase transitions widely exist in nature and occur when some control parameters are changed. In neural systems, their macroscopic states are represented by the activity states of neuron populations, and phase transitions between different activity states are closely related to corresponding functions in the brain. In particular, phase transitions to some rhythmic synchronous firing states play significant roles on diverse brain functions and disfunctions, such as encoding rhythmical external stimuli, epileptic seizure, etc. However, in previous studies, phase transitions in neuronal networks are almost driven by network parameters (e.g., external stimuli), and there has been no investigation about the transitions between typical activity states of neuronal networks in a self-organized way by applying plastic connection weights. In this paper, we discuss phase transitions in electrically coupled and lattice-based small-world neuronal networks (LBSW networks) under spike-timing-dependent plasticity (STDP). By applying STDP on all electrical synapses, various known and novel phase transitions could emerge in LBSW networks, particularly, the phenomenon of self-organized phase transitions (SOPTs): repeated transitions between synchronous and asynchronous firing states. We further explore the mechanics generating SOPTs on the basis of synaptic weight dynamics. 展开更多
关键词 spatiotemporal pattern self-organized phase transition small-world neuronal network spike-timing-dependent plasticity
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Optical patterns in spatially coupled phase-conjugate systems
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作者 岳立娟 桑金玉 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第11期187-193,共7页
Various pattern evolutions are presented in one- and two-dimensional spatially coupled phase-conjugate systems (SCPCSs). As the system parameters change, different patterns are obtained from the period-doubling of k... Various pattern evolutions are presented in one- and two-dimensional spatially coupled phase-conjugate systems (SCPCSs). As the system parameters change, different patterns are obtained from the period-doubling of kink-antikinks in space to the spatiotemporal chaos in a one-dimensional SCPCS. The homogeneous symmetric states induce symmetry breaking from the four corners and the boundaries, finally leading to spatiotemporal chaos with the increase of the iteration time in a two-dimensional SCPCS. Numerical simulations are very helpful for understanding the complex optical phenomena. 展开更多
关键词 pattern evolution phase-conjugate one- and two-dimensional spatially systems
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Flow patterns and their transition characteristics of the air-water two-phase flow in a horizontal pipe with a sudden-changed cross-section area
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作者 YANG Ying-Zhen LI Guang-Jun +3 位作者 ZHOU Fang-De CREN Xue-Jun (State Key Laboratory of Multiphase Flow in Power Engineering, Xi ’an Jiaotong University, Xi’an, 710049 Northwest Poaer Design Institute, Xi’an, 710068 School of Chemical Engineering, University 《Nuclear Science and Techniques》 SCIE CAS CSCD 2001年第1期44-52,共9页
Flow patterns in upstream and downstream straight tubes of sudden-changed areas in a horizontal straight pipe were experimentally examined. Both sudden-expansion cross-section (SECS) and sudden-contraction cross-secti... Flow patterns in upstream and downstream straight tubes of sudden-changed areas in a horizontal straight pipe were experimentally examined. Both sudden-expansion cross-section (SECS) and sudden-contraction cross-section (SCCS) were investigated. The flow pattern maps upstream and downstream were delineated and compared with those in straight tubes with uniform cross-sections. The effects of the SECS and SCCS on flow patterns were discussed and analyzed. Furthermore, flow pattern transition mechanisms resulting in occurrences of different flow patterns were simply discussed and some transition criteria for the flow pattern transitions were deduced by using the non-dimensionlized analysis method. 展开更多
关键词 气水二相流 水平管 相变特征 流图样
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MOLTEN SALT PHASE DIAGRAMS CALCULATION USING ARTIFICIAL NEURAL NETWORK OR PATTERN RECOGNITION-BOND PARAMETERS Part 2.Prediction of phase diagrams of ternary molten salt systems 被引量:1
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作者 Part 2. Prediction of phase diagrams of ternary molten salt systemsQiu Guanzhou, Wang Xueye and Wang DianzuoDepartment of Mineral Engineering, Central South University of Technology, Changsha 410083, P. R. ChinaChen NianyiShanghai Institut 《中国有色金属学会会刊:英文版》 CSCD 1998年第2期138-143,共6页
MOLTENSALTPHASEDIAGRAMSCALCULATIONUSINGARTIFICIALNEURALNETWORKORPATTERNRECOGNITIONBONDPARAMETERS①Part2.Predi... MOLTENSALTPHASEDIAGRAMSCALCULATIONUSINGARTIFICIALNEURALNETWORKORPATTERNRECOGNITIONBONDPARAMETERS①Part2.Predictionofphasediag... 展开更多
关键词 phase DIAGRAM CALCULATION artificial neural netwrok pattern recognition BOND parameter TERNARY MOLTEN SALT system
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Phase-only pattern synthesis based on gradient-descent optimization
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作者 Chengjun Lu Weixing Sheng +1 位作者 Yubing Han Xiaofeng Ma 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第2期297-307,共11页
By applying phase-only technique in array antenna pattern synthesis, antenna arrays can form desired patterns with the use of phase shifters only. A novel phase-only pattern synthesis algorithm is proposed for the pas... By applying phase-only technique in array antenna pattern synthesis, antenna arrays can form desired patterns with the use of phase shifters only. A novel phase-only pattern synthesis algorithm is proposed for the passive phased array seeker. This algorithm synthesizes the main beam of the antenna pattern through least-squares approximation, thus minimizing the errors between the actual and the desired main beams. The synthesis problem can be solved by applying gradient-descent optimization. The item for suppressing side lobes is added to the above synthesis problem. To obtain a side lobe level as low as possible, the algorithm assigns different weights to different directions in the side lobe region. The algorithm is run repeatedly and the weights are adjusted adaptively according to the normalized power in the side lobe directions. Detailed examples are presented to demonstrate the accuracy and effectiveness of the proposed approach. 展开更多
关键词 pattern synthesis phase-only gradient-descent adaptively
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Numerical Simulation of a Domain-Tessellation Pattern on a Spherical Surface Using a Phase Field Model 被引量:1
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作者 Takuya Uehara 《Open Journal of Modelling and Simulation》 2016年第2期24-33,共10页
A numerical simulation scheme is proposed to analyze domain tessellation and pattern formation on a spherical surface using the phase-field method. A multi-phase-field model is adopted to represent domain growth, and ... A numerical simulation scheme is proposed to analyze domain tessellation and pattern formation on a spherical surface using the phase-field method. A multi-phase-field model is adopted to represent domain growth, and the finite-difference method (FDM) is used for numerical integration. The lattice points for the FDM are distributed regularly on a spherical surface so that a mostly regular triangular domain division is realized. First, a conventional diffusion process is simulated using this lattice to confirm its validity. The multi-phase-field equation is then applied, and pattern formation processes under various initial conditions are simulated. Unlike pattern formation on a flat plane, where the regular hexagonal domains are always stable, certain different patterns are generated. Specifically, characteristic stable patterns are obtained when the number of domains, n, is 6, 8, or 12;for instance, a regular pentagonal domain division pattern is generated for n = 12, which corresponds to a regular dodecahedron. 展开更多
关键词 pattern Formation Domain Tessellation Computer Simulation phase Field Method
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Interfacial wave patterns and their transitions in gas-liquid two-phase flow through horizontal ducts
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作者 Li Guang Jun, Guo Lie Jin and Chen Xue JunNational Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong University, Xi’an 710049) 《Nuclear Science and Techniques》 SCIE CAS CSCD 1998年第1期39-44,共6页
InterfacialwavepaternsandtheirtransitionsingasliquidtwophaseflowthroughhorizontalductsLiGuangJun,GuoLieJinan... InterfacialwavepaternsandtheirtransitionsingasliquidtwophaseflowthroughhorizontalductsLiGuangJun,GuoLieJinandChenXueJun... 展开更多
关键词 气-液二相流 水平管 波模式 相变
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MOLTEN SALT PHASE DIAGRAMS CALCULATION USING ARTIFICIAL NEURAL NETWORK OR PATTERN RECOGNITION-BOND PARAMETERS
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作者 Wang Xueye, Qiu Guanzhou and Wang DianzuoDepartment of Mineral Engineering, Central South University of Technology, Changsha 410083, P. R. ChinaChen NianyiShanghai Institute of Metallurgy, Chinese Academy of Sciences, Shanghai 200050, P. R. Ch 《中国有色金属学会会刊:英文版》 CSCD 1998年第1期143-149,共7页
MOLTENSALTPHASEDIAGRAMSCALCULATIONUSINGARTIFICIALNEURALNETWORKORPATTERNRECOGNITIONBONDPARAMETERS①Part1.Thepr... MOLTENSALTPHASEDIAGRAMSCALCULATIONUSINGARTIFICIALNEURALNETWORKORPATTERNRECOGNITIONBONDPARAMETERS①Part1.Thepredictionofthepha... 展开更多
关键词 phase diagram CALCULATION artificial NEURAL network pattern RECOGNITION bond parameter binary MOLTEN SALT system
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CRYSTAL STRUCTURE OF A LONG-PERIOD ORDERED PHASE IN Fe-C MARTENSITE AND COMPUTER SIMULATION OF ITS ELECTRON DIFFRACTION PATTERNS
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作者 REN Xiaobing WANG Xiaotian +1 位作者 K.SHIMIZU T.TADAKI(National Laboratory of Solid State Microstructures,Nanjing University Nanjing 210093,China)(School of Materials Science and Engineering,Xi’an Jiaotong University Xi’an 710049,China)(Kanazawa Institute of Techn 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1996年第1期23-26,共4页
Different structure models of a long-period ordered phase in Fe-C martenstie formed during aging have been checked by computer simulation of electron diffraction(ED) patterns based on these models.The results showed t... Different structure models of a long-period ordered phase in Fe-C martenstie formed during aging have been checked by computer simulation of electron diffraction(ED) patterns based on these models.The results showed that the simulated ED pattern of γ'-FexC(Ⅱ) model proposed by the present authors is in good agreement with experimentally observed ED pattern.It was also confirmed that the incommensurate superperiod stems from the coexistence of several γ'-Fe_xC(H) phases with different superperiods.The Fe(144)C(24)(Fe6C) model proposed by Uwakweh et al.generated ED patterns remarkably different from the experimental ones. 展开更多
关键词 Fe-C martensite long-period ordered phase crystal structure computer simulation electron diffraction pattern
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Phase Identification Using Series of Selected Area Diffraction Patterns and Energy Dispersive Spectrometry within TEM
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作者 Kun-Lin Lin 《Microscopy Research》 2014年第4期57-66,共10页
Transmission electron microscopy (TEM) is a very powerful technique for materials characteriza-tion, providing information relating to morphology, composition, and crystal structure. Selected area diffraction patterns... Transmission electron microscopy (TEM) is a very powerful technique for materials characteriza-tion, providing information relating to morphology, composition, and crystal structure. Selected area diffraction patterns (SADPs) are crystallographic data that can be obtained using a TEM in-strument. Conventional identification through SADP/TEM is tricky and tedious, thereby increasing the difficulty of phase identification. To establish a procedure for phase identification of known and unknown phases, in this study we examined two samples: one, a known phase, was Si with alignment;the other, unknown, was the TixOy phase at the 96.4Au-3Ni-0.6Ti interlayer/ yttria-stabilized zirconia (YSZ) interface of a steel/96.4Au-3Ni-0.6Ti interlayer/YSZ joint. The procedures for phase identification of the known and unknown phases are described herein using a series of SADPs and energy dispersive spectrometry within TEM that would be useful for general researchers. 展开更多
关键词 phase Identification Transmission Electron MICROSCOPY SELECTED Area DIFFRACTION pattern Energy DISPERSIVE Spectroscopy
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Capacitor Pattern H-Bridge Multilevel Inverter (CPHMLI) Using Phase Diposition Pulse Width Modulation for Grid Applications
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作者 M. S. Saravanan R. Jeyabharath 《Circuits and Systems》 2016年第10期3310-3319,共10页
This work presents an implementation of an innovative single phase multilevel inverter using capacitors with reduced switches. The proposed Capacitor pattern H-bridge Multilevel Inverter (CPHMLI) topology consists of ... This work presents an implementation of an innovative single phase multilevel inverter using capacitors with reduced switches. The proposed Capacitor pattern H-bridge Multilevel Inverter (CPHMLI) topology consists of a proper number of Capacitor connected with switches and power sources. The advanced switching control supplied by Pulse Width Modulation (PDPWM) to attain mixed staircase switching state. The charging and discharging mode are achieved by calculating the voltage error at the load. Furthermore, to accomplish the higher voltage levels at the output with less number of semiconductors switches and simple commutation designed using CPHMLI topology. To prove the performance and effectiveness of the proposed approach, a set of experiments performed under various load conditions using MATLAB tool. 展开更多
关键词 Switched Capacitor Multilevel Inverter phase Diposition Pulse Width Modulation Capacitor pattern Based Multilevel Inverter Total Harmonic Distortion Cascaded H-Bridge 17-Level Inverter
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史蒂夫·里奇和他的《钢琴相位》(Piano Phase,1967) 被引量:1
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作者 徐昌俊 蔡妮辰 赵媛媛 《黄钟(武汉音乐学院学报)》 CSSCI 北大核心 2006年第1期30-33,共4页
史蒂夫·里奇(SteveReich)是当今美国现代音乐最具影响力的作曲家之一。文章从材料、调性、节奏、音高组织以及结构等方面,对他作于1967年为两架钢琴所作的《钢琴相位》,进行了综合分析。
关键词 史蒂夫·里奇 《钢琴相位》 相位作曲技术 模式 声部
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集群天线阵列:从确定性到随机建模
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作者 密铁宾 冯密宇 +2 位作者 邵睿初 曾操 邱才明 《电子科技大学学报》 北大核心 2026年第1期65-76,共12页
集群天线阵列由部署于无人平台的分布式天线单元构成,为无线感知与通信提供了前所未有的灵活性与环境适应性。然而,分布式架构及无人平台位置的随机扰动削弱了多天线单元的协同增益,对实现相干信号合成构成了严峻挑战。集群天线的空间... 集群天线阵列由部署于无人平台的分布式天线单元构成,为无线感知与通信提供了前所未有的灵活性与环境适应性。然而,分布式架构及无人平台位置的随机扰动削弱了多天线单元的协同增益,对实现相干信号合成构成了严峻挑战。集群天线的空间拓扑结构、平台的位置扰动以及天线规模对信号聚合性能的影响机理尚不明确。该文从确定性与随机性双重视角出发,探究集群天线阵列实现波束赋形的可行性。首先,针对多线性形式的集群天线阵列结构,构建了理论分析框架,推导了该类天线拓扑在波束合成过程中产生栅瓣的充要条件。对于双线性天线阵列,在不引入栅瓣的前提下,可放宽经典的半波长间距约束。该结论突破了传统均匀线性阵列设计中关于栅瓣抑制必须满足半波长间距的固有准则。随后,系统研究了天线位置扰动对波束赋形性能的影响。结果表明,天线的位置扰动将导致主瓣增益下降,主瓣增益的衰减无法通过单纯增加天线规模予以有效补偿;相反,增大天线规模的主要作用在于抑制旁瓣电平的波动方差,提升波束方向图的稳定性。最后,基于欧几里得随机矩阵的谱分析方法,研究了大规模无序天线阵列中涌现的确定性行为。当天线位置服从某种完全随机的空间分布时,其对应的欧几里得随机矩阵经验谱分布在天线数量趋于无穷时,几乎必然收敛于一个确定性极限。该结果揭示了无序天线阵列结构中蕴含的内在规律性,为后续大规模无序天线阵的建模与性能分析提供了必要的数学工具。 展开更多
关键词 集群天线阵列 阵列方向图 波束赋形 相位补偿 扰动 欧几里得随机矩阵
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