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Study on Preparation and Ns-Laser Damage of HfO<sub>2 </sub>Single Layers
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作者 Kesheng Guo Lang Hu +3 位作者 Hong Wei Qiang Hu Hongbo He Ping Xu 《Optics and Photonics Journal》 2021年第8期341-350,共10页
<div style="text-align:justify;"> The effects of the main parameters of argon flux, oxygen flux and beam voltage on the surface morphology, transmittance spectrum and laser damage of the HfO<sub>... <div style="text-align:justify;"> The effects of the main parameters of argon flux, oxygen flux and beam voltage on the surface morphology, transmittance spectrum and laser damage of the HfO<sub>2</sub> single layers prepared by ion beam sputtering are studied. The HfO<sub>2</sub> amorphous single layers have porous surface morphologies. Different processes will cause differences in coatings absorption and surface morphology, which in turn will cause changes in the spectral transmittance curve. The ion beam sputtering HfO<sub>2</sub> single layers have high content of argon (4.5% - 8%). The laser damage of HfO<sub>2</sub> single layers is related to argon inclusions and non-stoichiometric defects. The changes of argon flux and beam voltage have a greater impact on argon content and O/Hf ratio. When the argon content in the coatings is lower and the O/Hf ratio is higher, the laser damage thresholds of the HfO<sub>2</sub> single layers are higher. </div> 展开更多
关键词 HfO2 single layers Argon Flux Laser Damage Optical Coatings
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Experimental Study on a Single Layer Two-Way Grid Shell with Tension Members 被引量:3
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作者 Zhonghao Zhang Masumi Fujimoto +1 位作者 Atsuo Takino Katsuhiko Imai 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第4期10-19,共10页
Single layer two-way grid shell with in-plane and out-of-plane tension members is a new type of single-layer latticed shell roofs. Compared with traditional single-layer latticed shells,this new type has a unique mesh... Single layer two-way grid shell with in-plane and out-of-plane tension members is a new type of single-layer latticed shell roofs. Compared with traditional single-layer latticed shells,this new type has a unique mesh form and excellent rigidity. In order to further understand the buckling behaviors of single layer two-way grid cylindrical shell roof with tension members,the buckling experiments have been undertaken to investigate the effect of tension members,in either out-of-plane or in-plane placement. A single layer two-way grid cylindrical shell roof with out-of-plane tension members has been tested under symmetric and asymmetric loading. The tension member placement,the introducing initial axial force to tension members and the load patterns are considered to investigate the buckling behavior. Experimental results indicate that four long out-ofplane tension members work well under symmetrical loading,but only two long out-of-plane tension members work under asymmetrical loading. It can be concluded that the PC bar members used as tension members for this study are useful in the construction of a single layer two-way grid cylindrical shell roof with structural members intersecting at small angles. 展开更多
关键词 single layer two-way grid shell tension members out-of-plane placement buckling behavior truss system
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Stability of Low Crested and Submerged Breakwaters with Single Layer Armouring 被引量:4
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作者 Markus Muttray Erik ten Oever Bas Reedijk 《Journal of Shipping and Ocean Engineering》 2012年第3期140-152,共13页
The stability of single layer armour units on low crested and submerged breakwaters has been investigated in 2D hydraulic model tests. Armour unit movements including settlements, rocking and displacements have been d... The stability of single layer armour units on low crested and submerged breakwaters has been investigated in 2D hydraulic model tests. Armour unit movements including settlements, rocking and displacements have been determined. The effect of freeboard, packing density and wave steepness on the armour layer stability on crest, front and rear slope has been investigated. Armour units were mostly displaced in the most upper part of the seaward slope and at the seaward side of the crest. Damage on the crest was progressing towards the rear slope. About 40% to 50% larger armour units are required on the seaward slope and crest of low crested structures (as compared to conventional high crested breakwaters). About 35% larger armour units are required on the rear slope. Larger armour units are not required on submerged breakwaters if the water depth on the crest exceeds 40% of design wave height. 展开更多
关键词 Rubble mound breakwater low crested breakwater armour layer stability single layer armour units Xbloc.
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Domain Decomposition for Wavelet Single Layer on Geometries with Patches 被引量:3
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作者 Maharavo Randrianarivony 《Applied Mathematics》 2016年第15期1798-1823,共27页
We focus on the single layer formulation which provides an integral equation of the first kind that is very badly conditioned. The condition number of the unpreconditioned system increases exponentially with the multi... We focus on the single layer formulation which provides an integral equation of the first kind that is very badly conditioned. The condition number of the unpreconditioned system increases exponentially with the multiscale levels. A remedy utilizing overlapping domain decompositions applied to the Boundary Element Method by means of wavelets is examined. The width of the overlapping of the subdomains plays an important role in the estimation of the eigenvalues as well as the condition number of the additive domain decomposition operator. We examine the convergence analysis of the domain decomposition method which depends on the wavelet levels and on the size of the subdomain overlaps. Our theoretical results related to the additive Schwarz method are corroborated by numerical outputs. 展开更多
关键词 WAVELET single Layer PATCH Domain Decomposition Convergence Graph Partitioning Condition Number
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Study on electrical defects level in single layer two-dimensional Ta2O5 被引量:1
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作者 李大海 宋雄飞 +5 位作者 胡林峰 王子仪 张荣君 陈良尧 张卫 周鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第4期339-343,共5页
Two-dimensional atomic-layered material is a recent research focus, and single layer Ta205 used as gate dielectric in field-effect transistors is obtained via assemblies of Ta205 nanosheets. However, the electrical pe... Two-dimensional atomic-layered material is a recent research focus, and single layer Ta205 used as gate dielectric in field-effect transistors is obtained via assemblies of Ta205 nanosheets. However, the electrical performance is seriously affected by electronic defects existing in Ta2Os. Therefore, spectroscopic ellipsometry is used to calculate the transition energies and corresponding probabilities for two different charged oxygen vacancies, whose existence is revealed by x-ray photoelectron spectroscopy analysis. Spectroscopic ellipsometry fitting also calculates the thickness of single layer Ta2Os, exhibiting good agreement with atomic force microscopy measurement. Nondestructive and noncontact spectroscopic ellipsometry is appropriate for detecting the electrical defects level of single layer Ta2O5. 展开更多
关键词 single layer electronic defects spectroscopic ellipsometry
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Steady thermocapillary-buoyant convection in a shallow annular pool. Part 1:Single layer fluid 被引量:1
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作者 You-Rong Li Shuang-Cheng Wang Chuan-Mei Wu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2011年第3期360-370,共11页
This paper examines the steady thermocapillarybuoyant convection in a shallow annular pool subjected to a radial temperature gradient. A matched asymptotic theory is used to obtain the asymptotic solutions of the flow... This paper examines the steady thermocapillarybuoyant convection in a shallow annular pool subjected to a radial temperature gradient. A matched asymptotic theory is used to obtain the asymptotic solutions of the flow and thermal fields in the case of small aspect ratios,which is defined as the ratio of the layer thickness to the gap width. The flow domain is divided into the core region away from the cylinder walls and two end regions near each cylinder wall. Asymptotic solutions are obtained in the core region by solving the core and end flows separately and then joining them through matched asymptotic expansions. For the system of silicon melt,the asymptotic solutions are compared with the results of numerical simulations. It is found that the two kinds of solutions have a good agreement in the core region for a small aspect ratio. With the increase of aspect ratio,the applicability of the present asymptotic solutions decreases gradually. 展开更多
关键词 Thermocapillary-buoyant flow. Annular shallow pool. single layer fluid. Asymptotic solution
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Calculating single layer production contribution of heavy oil commingled wells by analysis of aromatic parameters in whole-oil GC-MS
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作者 Xu Yaohui Ma Li +3 位作者 Li Linxiang Cui Wenfu Cheng Xiaowei Wang Xiaoping 《Petroleum Science》 SCIE CAS CSCD 2014年第1期89-96,共8页
Traditional fluid production profile logging is not usually suitable for heavy-viscous crude oil wells.Biodegradation of heavy oil can lead to the loss of n-alkanes,and the use of chromatogram fingerprint techniques i... Traditional fluid production profile logging is not usually suitable for heavy-viscous crude oil wells.Biodegradation of heavy oil can lead to the loss of n-alkanes,and the use of chromatogram fingerprint techniques in studying the production contributions of single layers in heavy oil commingled wells has limitations.However,aromatic compounds are relatively well preserved.We took the heavy oil commingled wells of small layers NG55 and NG61 in the ninth area of the Gudong oil field as examples.Based on the principle of chromatography,the whole-oil GC-MS was used,and the aromatic parameters which have a strongly linear relationship with the ratio of mixed two end member oils were verified and selected in laboratory.Studies showed that the ratio of (1,4,6-+ 2,3,6-trimethylnaphthalene) to 1,2,5-trimethylnaphthalene has a strongly linear relationship with the ratio of the mixed two end member oils (R2=0.992).The oil contributions from single layers NG55 and NG61 in six commingled heavy oil wells were calculated using established charts and this relationship.The calculated results are consistent with the results of long period dynamic monitoring and logging interpretation in the study area and can provide a scientific basis for monitoring production performance and hierarchical management of reservoirs.The study provides a new geochemical method for calculation of the contributions of single layers in heavy oil commingled wells when conventional fluid production profile logging is not suitable. 展开更多
关键词 Whole-oil GC-MS aromatic parameters commingled producing wells single layer production the ninth area of the Gudong oilfield
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Vertical two-dimensional non-hydrostatic pressure model with single layer
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作者 康玲 郭晓明 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2013年第6期721-730,共10页
The vertical two-dimensional non-hydrostatic pressure models with multiple layers can make prediction more accurate than those obtained by the hydrostatic pres- sure assumption. However, they are time-consuming and un... The vertical two-dimensional non-hydrostatic pressure models with multiple layers can make prediction more accurate than those obtained by the hydrostatic pres- sure assumption. However, they are time-consuming and unstable, which makes them unsuitable for wider application. In this study, an efficient model with a single layer is developed. Decomposing the pressure into the hydrostatic and dynamic components and integrating the x-momentum equation from the bottom to the free surface can yield a horizontal momentum equation, in which the terms relevant to the dynamic pressure are discretized semi-implicitly. The convective terms in the vertical momentum equation are ignored, and the rest of the equation is approximated with the Keller-box scheme. The velocities expressed as the unknown dynamic pressure are substituted into the continuity equation, resulting in a tri-diagonal linear system solved by the Thomas algorithm. The validation of solitary and sinusoidal waves indicates that the present model can provide comparable results to the models with multiple layers but at much lower computation cost. 展开更多
关键词 vertical two-dimensional model non-hydrostatic pressure single layer Thomas algorithm WAVE
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Compressed Sensing Based on the Single Layer Wavelet Transform for Image Fusion
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作者 Guohui Yang Wude Xu +5 位作者 Bo Zheng Fanglan Ma Xuhui Yang Hongwei Ma Hongxia Zhang Genliang Han 《Journal of Computer and Communications》 2016年第15期107-116,共10页
In this paper, a new method of combination single layer wavelet transform and compressive sensing is proposed for image fusion. In which only measured the high-pass wavelet coefficients of the image but preserved the ... In this paper, a new method of combination single layer wavelet transform and compressive sensing is proposed for image fusion. In which only measured the high-pass wavelet coefficients of the image but preserved the low-pass wavelet coefficient. Then, fuse the low-pass wavelet coefficients and the measurements of high-pass wavelet coefficient with different schemes. For the reconstruction, by using the minimization of total variation algorithm (TV), high-pass wavelet coefficients could be recovered by the fused measurements. Finally, the fused image could be reconstructed by the inverse wavelet transform. The experiments show the proposed method provides promising fusion performance with a low computational complexity. 展开更多
关键词 Image Fusion Compressed Sensing single Layer Wavelet Transform
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Single Layer Centrifugation with Androcoll-E^(TM) improved progressive motility and percentage of live spermatozoa with intact acrosome of chilled stallion semen but did not have an effect on DNA integrity
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作者 Ana Luisa Costa Ana Martins-Bessa +8 位作者 Ana Rebello de Andrade Tiago Guimaraes Maria Rosa Rebordao Sandra Gamboa Pedro Pinto Bravo Maria José Correia Jorge Colaco Isabel Gaivao António Rocha 《Open Journal of Animal Sciences》 2012年第3期159-165,共7页
A significant number of stallions produce low quality ejaculates with high sensibility to chilling. Single Layer Centrifugation (SLC) with Andro-coll-ETM has been presented as an efficient method of selecting good qua... A significant number of stallions produce low quality ejaculates with high sensibility to chilling. Single Layer Centrifugation (SLC) with Andro-coll-ETM has been presented as an efficient method of selecting good quality spermatozoa. In the current study, changes in sperm quality (motility, viability, acrosome integrity and DNA damage) occurring during storage at 5?C for a maximum of 72 h, were investigated. For that, one ejaculate from 12 stallions was split in two aliquots: control and SLC-selected. Both aliquots were chilled and stored at 5?C and spermatozoa were evaluated for motility, viability and acrosome integrity at 24, 48 and 72 h post collection. DNA damage was evaluated at 48 h post collection using the comet assay. In the SLC-selected aliquots, there was a significant improvement in terms of progressive motility (0 h: P = 0.005;24 h: P 0.05). SLC with Androcoll-ETM improved semen quality prolonging sperm longevity of chilled semen (P = 0.012). This positive effect was more evident in ejaculates most sensitive to chilling that had a sharp decrease in motility in the first 24 h of refrigeration and for all ejaculates at 72 h post-chilling. Therefore, this method reveals to be a useful technique for selecting spermatozoa and maintain sperm quality during storage. 展开更多
关键词 Stallion Sperm single Layer Centrifugation Androcoll-ETM Membrane Integrity Comet assay Component Formatting Style Styling
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Geometrical Dimensional Effect on Natural Frequency of Single Layer Graphene in Armchair Configuration
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作者 Harshad Patel 《Journal of Mechanical Engineering Research》 2021年第2期45-51,共7页
Graphene has remarkable strength,such as yield strength and elastic constant.The dynamic behaviour of graphene sheet is affected by geometrical variation in atomic arrangement.This paper introduced graphene with armch... Graphene has remarkable strength,such as yield strength and elastic constant.The dynamic behaviour of graphene sheet is affected by geometrical variation in atomic arrangement.This paper introduced graphene with armchair atomic structure for estimating fundamental natural frequencies.The presented analysis can be useful for the possible high frequency nanomechanical resonator systems.The analytical formulation,based on classical plate theory and continuum solid modelling based finite element method have been performed for estimation of fundamental natural frequencies of single layer graphene sheet(SGLS)with different boundary conditions.The free edge and clamped edge boundary conditions have been considered.For simplifying analytical formulations,Blevins approach for dynamic solution has been adopted and for validating analytical results.The finite element analysis of SLGS has been performed using ANSYS software.The effect of variation in geometrical parameters in terms of width and length of SLGS has been analysed for realization of ultra-high frequency based nanomechanical resonator systems. 展开更多
关键词 single layer graphene sheet(SLGS) Size variation Fundamental natural frequency Finite element analysis
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Hybrid Deep Learning-Improved BAT Optimization Algorithm for Soil Classification Using Hyperspectral Features
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作者 S.Prasanna Bharathi S.Srinivasan +1 位作者 G.Chamundeeswari B.Ramesh 《Computer Systems Science & Engineering》 SCIE EI 2023年第4期579-594,共16页
Now a days,Remote Sensing(RS)techniques are used for earth observation and for detection of soil types with high accuracy and better reliability.This technique provides perspective view of spatial resolution and aids ... Now a days,Remote Sensing(RS)techniques are used for earth observation and for detection of soil types with high accuracy and better reliability.This technique provides perspective view of spatial resolution and aids in instantaneous measurement of soil’s minerals and its characteristics.There are a few challenges that is present in soil classification using image enhancement such as,locating and plotting soil boundaries,slopes,hazardous areas,drainage condition,land use,vegetation etc.There are some traditional approaches which involves few drawbacks such as,manual involvement which results in inaccuracy due to human interference,time consuming,inconsistent prediction etc.To overcome these draw backs and to improve the predictive analysis of soil characteristics,we propose a Hybrid Deep Learning improved BAT optimization algorithm(HDIB)for soil classification using remote sensing hyperspectral features.In HDIB,we propose a spontaneous BAT optimization algorithm for feature extraction of both spectral-spatial features by choosing pure pixels from the Hyper Spectral(HS)image.Spectral-spatial vector as training illustrations is attained by merging spatial and spectral vector by means of priority stacking methodology.Then,a recurring Deep Learning(DL)Neural Network(NN)is used for classifying the HS images,considering the datasets of Pavia University,Salinas and Tamil Nadu Hill Scene,which in turn improves the reliability of classification.Finally,the performance of the proposed HDIB based soil classifier is compared and analyzed with existing methodologies like Single Layer Perceptron(SLP),Convolutional Neural Networks(CNN)and Deep Metric Learning(DML)and it shows an improved classification accuracy of 99.87%,98.34%and 99.9%for Tamil Nadu Hills dataset,Pavia University and Salinas scene datasets respectively. 展开更多
关键词 HDIB bat optimization algorithm recurrent deep learning neural network convolutional neural network single layer perceptron hyperspectral images deep metric learning
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Extreme learning with chemical reaction optimization for stock volatility prediction 被引量:2
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作者 Sarat Chandra Nayak Bijan Bihari Misra 《Financial Innovation》 2020年第1期290-312,共23页
Extreme learning machine(ELM)allows for fast learning and better generalization performance than conventional gradient-based learning.However,the possible inclusion of non-optimal weight and bias due to random selecti... Extreme learning machine(ELM)allows for fast learning and better generalization performance than conventional gradient-based learning.However,the possible inclusion of non-optimal weight and bias due to random selection and the need for more hidden neurons adversely influence network usability.Further,choosing the optimal number of hidden nodes for a network usually requires intensive human intervention,which may lead to an ill-conditioned situation.In this context,chemical reaction optimization(CRO)is a meta-heuristic paradigm with increased success in a large number of application areas.It is characterized by faster convergence capability and requires fewer tunable parameters.This study develops a learning framework combining the advantages of ELM and CRO,called extreme learning with chemical reaction optimization(ELCRO).ELCRO simultaneously optimizes the weight and bias vector and number of hidden neurons of a single layer feed-forward neural network without compromising prediction accuracy.We evaluate its performance by predicting the daily volatility and closing prices of BSE indices.Additionally,its performance is compared with three other similarly developed models—ELM based on particle swarm optimization,genetic algorithm,and gradient descent—and find the performance of the proposed algorithm superior.Wilcoxon signed-rank and Diebold–Mariano tests are then conducted to verify the statistical significance of the proposed model.Hence,this model can be used as a promising tool for financial forecasting. 展开更多
关键词 Extreme learning machine single layer feed-forward network Artificial chemical reaction optimization Stock volatility prediction Financial time series forecasting Artificial neural network Genetic algorithm Particle swarm optimization
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Study on Characteristics of Underground Horizontal Electric Field Caused by Lightning Return Stroke Based on FDTD Method 被引量:1
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作者 Zhao Liang Gu Lili +1 位作者 Hao Ling Liu Ruixiang 《Meteorological and Environmental Research》 CAS 2019年第1期39-42,共4页
Based on the MTLL lightning return stroke model,a two-dimensional cylindrical finite-difference time-domain( FDTD) model for underground horizontal electric field was established,and the effects of distance from light... Based on the MTLL lightning return stroke model,a two-dimensional cylindrical finite-difference time-domain( FDTD) model for underground horizontal electric field was established,and the effects of distance from lightning channel,depth,soil electrical conductivity and its distribution,and return stroke current on the characteristics of underground horizontal electric field were analyzed. The results showed that as long as the electrical conductivity of soil existed,the peak of underground horizontal electric field decreased with the increase in the horizontal distance from lightning channel. When the electrical conductivity of the upper soil was much smaller than that of the lower soil,the peak of corresponding horizontal electric field was larger than the electric field peak as the electrical conductivity of the upper soil was larger than that of the lower soil. When the electrical conductivity of the upper soil was less than that of the lower soil,the growth and decay of the horizontal electric field were faster than the growth and decay as the electrical conductivity of the upper soil was larger than that of the lower soil. 展开更多
关键词 Underground horizontal electric field Lightning return stroke FDTD single layer soil Layered soil
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Recent Development of Reluctance Machines with Different Winding Configurations,Excitation Methods,and Machine Structures 被引量:1
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作者 X.Y.Ma G.J.Li +1 位作者 G.W.Jewell Z.Q.Zhu 《CES Transactions on Electrical Machines and Systems》 2018年第1期82-92,共11页
This paper reviews the performances of some newly developed reluctance machines with different winding configurations,excitation methods,stator and rotor structures,and slot/pole number combinations.Both the double la... This paper reviews the performances of some newly developed reluctance machines with different winding configurations,excitation methods,stator and rotor structures,and slot/pole number combinations.Both the double layer conventional(DLC-),double layer mutually-coupled(DLMC),single layer conventional(SLC-),and single layer mutually-coupled(SLMC-),as well as fully-pitched(FP)winding configurations have been considered for both rectangular wave and sinewave excitations.Different conduction angles such as unipolar􀫚120°elec.,unipolar/bipolar􀫚180°elec.,bipolar􀫛240°elec.and bipolar􀫜360°elec.have been adopted and the most appropriate conduction angles have been obtained for the SRMs with different winding configurations.In addition,with appropriate conduction angles,the 12-slot/14-pole SRMs with modular stator structure is found to produce similar average torque,but lower torque ripple and iron loss when compared to non-modular 12-slot/8-pole SRMs.With sinewave excitation,the doubly salient synchronous reluctance machines with the DLMC winding can produce the highest average torque at high currents and achieve the highest peak efficiency as well.In order to compare with the conventional synchronous reluctance machines(SynRMs)having flux barriers inside the rotor,the appropriate rotor topologies to obtain the maximum average torque have been investigated for different winding configurations and slot/pole number combinations.Furthermore,some prototypes have been built with different winding configurations,stator structures,and slot/pole combinations to validate the predictions. 展开更多
关键词 Double/single layer windings excitation methods fully/short-pitched mutually coupled modular machines switched/synchronous reluctance machines
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High Gain Patch Antenna for 2.4GHz using Metamaterial Superstrate
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作者 Kyu-Chang LEE Seung-In YANG 《Journal of Measurement Science and Instrumentation》 CAS 2010年第S1期19-22,共4页
A patch antenna and our proposed metamaterial patch antenna are simulated and compared. A high gain patch antenna using a single layer metamaterial superstrate with a near to zero refractive index(n)is proposed.The si... A patch antenna and our proposed metamaterial patch antenna are simulated and compared. A high gain patch antenna using a single layer metamaterial superstrate with a near to zero refractive index(n)is proposed.The simulation results provide that the gain of the proposed antenna is increased by about 7dB. Consequently,the high gain antenna can be easily obtained by using our metamaterial superstrate. 展开更多
关键词 Patch Antenna METAMATERIAL Superstrate single Layer
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Distributional Relations on Impulse Radiating Surface and Point Type Sources
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作者 Burak Polat 《Journal of Mathematics and System Science》 2012年第2期72-81,共10页
The electromagnetic field relations are demonstrated on impulse radiating surface and point type sources, which are characterized by first and second order singularities at rest in a Schwartz-Sobolev space setting. Th... The electromagnetic field relations are demonstrated on impulse radiating surface and point type sources, which are characterized by first and second order singularities at rest in a Schwartz-Sobolev space setting. The investigation starts with a general introduction to Schwartz-Sobolev distributions, the electromagnetic field equations and various modes of impulsive radiation. This is followed by an outline of temporal distributional relations in arbitrary media and distributional derivative operations on an arbitrary regular surface, all of which are employed in an investigation of impulse radiation mechanism on single and double layer sources. Similar steps are followed in a description of point distributions and investigation of impulse radiation mechanism on electric and magnetic point dipoles. 展开更多
关键词 Generalized functions electromagnetic phenomena single and double layers point sources impulse radiation.
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SnO_2 hollow nanospheres assembled by single layer nanocrystals as anode material for high performance Li ion batteries 被引量:7
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作者 Wei Wei Ling-Xiao Song Lin Guo 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第1期124-128,共5页
SnO2 hollow nanospheres were successfully synthesized via a facile one-step solvothermal method.Characterizations show that the as-prepared SnO2 spheres are of hollow structure with a diameter at around 50 nm,and espe... SnO2 hollow nanospheres were successfully synthesized via a facile one-step solvothermal method.Characterizations show that the as-prepared SnO2 spheres are of hollow structure with a diameter at around 50 nm,and especially,the shell of the spheres is assembled by single layer SnO2 nanocrystals.The surface area of the material reaches up to 202.5 m^2/g.As an anode material for Li ion batteries,the sample exhibited improved electrochemical performance compared with commercial SnO2 particles.After cycled at high current rate of 0.5 C,1 C and 0.5 C for 20 cycles,respectively,the electrode can maintain a capacity of 509 mAh/g.The suitable shell thickness/diameter ratio endows the good structural stability of the material during cycling,which promises the excellent cycling performance of the electrode.The large surface area and the ultra thin shell ensure the high rate performance of the material. 展开更多
关键词 SNO2 Hollow nanospheres single layer Li ion batteries
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Synthesis of Large Area, Homogeneous, Single Layer Graphene Films by Annealing Amorphous Carbon on Co and Ni 被引量:5
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作者 Carlo M. Orofeo Hiroki Ago +1 位作者 Baoshan Hu Masaharu Tsuji 《Nano Research》 SCIE EI CAS CSCD 2011年第6期531-540,共10页
The synthesis of large area, homogenous, single layer graphene on cobalt (Co) and nickel (Ni) is reported. The process involves vacuum annealing of sputtered amorphous carbon (a-C) deposited on Co/sapphire or Ni... The synthesis of large area, homogenous, single layer graphene on cobalt (Co) and nickel (Ni) is reported. The process involves vacuum annealing of sputtered amorphous carbon (a-C) deposited on Co/sapphire or Ni/sapphire substrates. The improved crystallinity of the metal film, assisted by the sapphire substrate, proves to be the key to the quality of as-grown graphene film. The crystallinity of the Co and Ni metal films was improved by sputtering the metal at elevated temperature as was verified by X-ray diffraction (XRD). After sputtering of a-C and annealing, large area, single layer graphene that occupies almost the entire area of the substrate was produced. With this method, 100 mm2-area single layer graphene can be synthesized and is limited only by the substrate and vacuum chamber size. The homogeneity of the graphene film is not dependent on the cooling rate, in contrast to syntheses using polycrystalline metal films and conventional chemical vapor deposition (CVD) growth. Our facile method of producing single layer graphene on Co and Ni metal films should lead to large scale graphene-based applications. 展开更多
关键词 single layer graphene amorphous carbon epitaxial metal ANNEALING
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A Framework for Distributed Semi-supervised Learning Using Single-layer Feedforward Networks 被引量:1
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作者 Jin Xie San-Yang Liu Jia-Xi Chen 《Machine Intelligence Research》 EI CSCD 2022年第1期63-74,共12页
This paper aims to propose a framework for manifold regularization(MR) based distributed semi-supervised learning(DSSL) using single layer feed-forward neural network(SLFNN). The proposed framework, denoted as DSSL-SL... This paper aims to propose a framework for manifold regularization(MR) based distributed semi-supervised learning(DSSL) using single layer feed-forward neural network(SLFNN). The proposed framework, denoted as DSSL-SLFNN is based on the SLFNN, MR framework, and distributed optimization strategy. Then, a series of algorithms are derived to solve DSSL problems. In DSSL problems, data consisting of labeled and unlabeled samples are distributed over a communication network, where each node has only access to its own data and can only communicate with its neighbors. In some scenarios, DSSL problems cannot be solved by centralized algorithms. According to the DSSL-SLFNN framework, each node over the communication network exchanges the initial parameters of the SLFNN with the same basis functions for semi-supervised learning(SSL). All nodes calculate the global optimal coefficients of the SLFNN by using distributed datasets and local updates. During the learning process, each node only exchanges local coefficients with its neighbors rather than raw data. It means that DSSL-SLFNN based algorithms work in a fully distributed fashion and are privacy preserving methods. Finally, several simulations are presented to show the efficiency of the proposed framework and the derived algorithms. 展开更多
关键词 Distributed learning(DL) semi-supervised learning(SSL) manifold regularization(MR) single layer feed-forward neural network(SLFNN) privacy preserving
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