期刊文献+
共找到17篇文章
< 1 >
每页显示 20 50 100
Ultraviolet-shielding and conductive double functional films coated on glass substrates by sol-gel process 被引量:2
1
作者 董玉红 赵青南 +1 位作者 吴硕 卢秀强 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第S1期446-450,共5页
Ultraviolet-shielding and conductive double functional films were composed of CeO2-TiO2 film and SnO2:Sb film deposited on glass substrates using sol-gel process.Ce(NO3)3·6H2O and Ti(C4H9O4),SnCl4 and SbCl3 were ... Ultraviolet-shielding and conductive double functional films were composed of CeO2-TiO2 film and SnO2:Sb film deposited on glass substrates using sol-gel process.Ce(NO3)3·6H2O and Ti(C4H9O4),SnCl4 and SbCl3 were used as precursors of the two different functional films respectively.The CeO2-TiO2 films were deposited on glass substrates by sol-gel dip coating method,and then the SnO2:Sb films with different thickness were deposited on the pre-coated CeO2-TiO2 thin film glass substrates,finally,the substrates coated with double functional films were annealed at different temperatures.The optical and electrical properties of the CeO2-TiO2 films and the double films were measured by UV-Vis spectrometer and four probe resistance measuring instrument.The crystal structures and surface morphology of the films were characterized using XRD and optical microscope,respectively.The obtained results show that the ultraviolet-shielding rate of the glass substrates with CeO2-TiO2 films is not less than 90%,and transmittance in visible lights can reach 65%.With the thickness of the SnO2:Sb film increasing,its conductivity became better,and the surface resistance is about 260 Ω/ when the SnO2:Sb films were deposited 11 cycles of the dip on the pre-coated CeO2-TiO2 glass.The ultraviolet-shielding rate of the glass substrates with double functional films is higher than 97%,and the peak transmittance in the visible lights is 72%.Additionally,with increasing the heat treatment time,the Na+ of the glass substrates diffuses into the films,resulting in the particle size of SnO2 crystal smaller. 展开更多
关键词 ultraviolet-shielding/conductive double functional films CeO2-TiO2 SnO2:Sb Glass substrates sol-gel rare earths
原文传递
ON DOUBLE PEAK PROBABILITY DENSITY FUNCTIONS OF DUFFING OSCILLATOR TO COMBINED DETERMINISTIC AND RANDOM EXCITATIONS
2
作者 戎海武 王向东 +2 位作者 孟光 徐伟 方同 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第11期1569-1576,共8页
The principal resonance of Duffing random external excitation was investigated. oscillator to combined deterministic and The random excitation was taken to be white noise or harmonic with separable random amplitude an... The principal resonance of Duffing random external excitation was investigated. oscillator to combined deterministic and The random excitation was taken to be white noise or harmonic with separable random amplitude and phase. The method of multiple scales was used to determine the equations of modulation of amplitude and phase. The one peak probability density function of each of the two stable stationary solutions was calculated by the linearization method. These two one-peak-density functions were combined using the probability of realization of the two stable stationary solutions to obtain the double peak probability density function. The theoretical analysis are verified by numerical results. 展开更多
关键词 Duffing oscillator double peak probability density function multiple scale method linearization method
下载PDF
Remote Sensing Plateau Forest Segmentation with Boundary Preserving Double Loss Function Collaborative Learning
3
作者 Ying Ma Jiaqi Zhang +3 位作者 Pengyu Liu Zhihao Wei Lingfei Zhang Xiaowei Jia 《Journal of New Media》 2022年第4期165-177,共13页
Plateau forest plays an important role in the high-altitude ecosystem,and contributes to the global carbon cycle.Plateau forest monitoring request in-suit data from field investigation.With recent development of the r... Plateau forest plays an important role in the high-altitude ecosystem,and contributes to the global carbon cycle.Plateau forest monitoring request in-suit data from field investigation.With recent development of the remote sensing technic,large-scale satellite data become available for surface monitoring.Due to the various information contained in the remote sensing data,obtain accurate plateau forest segmentation from the remote sensing imagery still remain challenges.Recent developed deep learning(DL)models such as deep convolutional neural network(CNN)has been widely used in image processing tasks,and shows possibility for remote sensing segmentation.However,due to the unique characteristics and growing environment of the plateau forest,generate feature with high robustness needs to design structures with high robustness.Aiming at the problem that the existing deep learning segmentation methods are difficult to generate the accurate boundary of the plateau forest within the satellite imagery,we propose a method of using boundary feature maps for collaborative learning.There are three improvements in this article.First,design a multi input model for plateau forest segmentation,including the boundary feature map as an additional input label to increase the amount of information at the input.Second,we apply a strong boundary search algorithm to obtain boundary value,and propose a boundary value loss function.Third,improve the Unet segmentation network and combine dense block to improve the feature reuse ability and reduces the image information loss of the model during training.We then demonstrate the utility of our method by detecting plateau forest regions from ZY-3 satellite regarding to Sanjiangyuan nature reserve.The experimental results show that the proposed method can utilize multiple feature information comprehensively which is beneficial to extracting information from boundary,and the detection accuracy is generally higher than several state-of-art algorithms.As a result of this investigation,the study will contribute in several ways to our understanding of DL for region detection and will provide a basis for further researches. 展开更多
关键词 Remote sensing forest segmentation boundary preserving double loss function
下载PDF
Nonlinear thermo-mechanical stability of eccentrically stiffened functionally graded material sandwich doubly curved shallow shells with general sigmoid law and power law according to third-order shear deformation theory
4
作者 D.V.DUNG D.T.DONG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第2期191-216,共26页
In this paper, the nonlinear analysis of stability of functionally graded ma- terial (FGM) sandwich doubly curved shallow shells is studied under thermo-mechanical loads with material properties obeying the general ... In this paper, the nonlinear analysis of stability of functionally graded ma- terial (FGM) sandwich doubly curved shallow shells is studied under thermo-mechanical loads with material properties obeying the general sigmoid law and power law of four ma- terial models. Shells are reinforced by the FGM stiffeners and rest on elastic foundations. Theoretical formulations are derived by the third-order shear deformation theory (TSDT) with the von Karman-type nonlinearity taking into account the initial geometrical im- perfection and smeared stiffener technique. The explicit expressions for determining the critical buckling load and the post-buckling mechanical and thermal load-deflection curves are obtained by the Galerkin method. Two iterative algorithms are presented. The effects of the stiffeners, the thermal element, the distribution law of material, the initial imper- fection, the foundation, and the geometrical parameters on buckling and post-buckling of shells are investigated. 展开更多
关键词 functionally graded material (FGM) sandwich double curved shallow shell thermo-mechanical stability FGM stiffener elastic foundation
下载PDF
引发内蒙古汛期暴雨洪涝灾害的降水事件雨强特征分析
5
作者 常煜 冀刚 +1 位作者 高绍鑫 刘静 《暴雨灾害》 2023年第3期346-352,共7页
选取2017—2018年汛期(6—8月)内蒙古108例引发暴雨洪涝灾害的降水事件,对其雨强持续性、最大值、日变化等特征进行分析,通过双重e指数函数和百分位相结合方法,确定降水事件阈值。结果表明:(1)降水事件高发区在大兴安岭东部,最高可达5~6... 选取2017—2018年汛期(6—8月)内蒙古108例引发暴雨洪涝灾害的降水事件,对其雨强持续性、最大值、日变化等特征进行分析,通过双重e指数函数和百分位相结合方法,确定降水事件阈值。结果表明:(1)降水事件高发区在大兴安岭东部,最高可达5~6次,持续时间最长为10d,降水事件次高发区在阴山山脉以南;(2)降水事件雨强最大值和最小值均出现在东部地区,极差最大值达70.4mm·h^(-1),西部和中部地区雨强最大值较接近,中部地区雨强极差最小,为16.0mm·h^(-1),但降水事件平均雨强最大值出现在西部地区,最小值出现在中部地区;(3)降水事件雨强日变化特征具有地域性差异,西部地区雨强(平均雨强)最大值出现时间具有分散不集中且差异较大的特点,易出现在凌晨、早晨、中午和傍晚,中部和东部地区易出现在中午和下午;(4)西部、中部和东部地区降水事件阈值分别为13.8mm·h^(-1)、10.0mm·h^(-1)和14.2mm·h^(-1)。 展开更多
关键词 降水事件 洪涝灾害 雨强特征 双重e指数函数 百分位方法
下载PDF
NEW PERIODIC SOLUTIONS OF NONLINEAR EVOLUTION EQUATIONS
6
作者 Shen Shoufeng Pan ZuliangDept.of Math.,Zhejiang Univ.,Hangzhou 310027,China 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第4期425-430,共6页
In this paper,some new periodic solutions of nonlinear evolution equations and corresponding travelling wave solutions are obtained by using the double function method and Jacobi elliptic functions.
关键词 nonlinear evolution equation Jacobi elliptic function method double function method.
下载PDF
Quantum twisted double-slits experiments:confirming wavefunctions'physical reality 被引量:9
7
作者 Zhi-Yuan Zhou Zhi-Han Zhu +7 位作者 Shi-Long Liu Yin-Hai Li Shuai Shi Dong-Sheng Ding Li-Xiang Chen Wei Gao Guang-Can Guo Bao-Sen Shi 《Science Bulletin》 SCIE EI CAS CSCD 2017年第17期1185-1192,共8页
Are quantum states real? This most fundamental question in quantum mechanics has not yet been satisfactorily resolved, although its realistic interpretation seems to have been rejected by various delayedchoice experim... Are quantum states real? This most fundamental question in quantum mechanics has not yet been satisfactorily resolved, although its realistic interpretation seems to have been rejected by various delayedchoice experiments. Here, to address this long-standing issue, we present a quantum twisted double-slit experiment. By exploiting the subluminal feature of twisted photons, the real nature of a photon during its time in flight is revealed for the first time. We found that photons' arrival times were inconsistent with the states obtained in measurements but agreed with the states during propagation. Our results demonstrate that wavefunctions describe the realistic existence and evolution of quantum entities rather than a pure mathematical abstraction providing a probability list of measurement outcomes. This finding clarifies the long-held misunderstanding of the role of wavefunctions and their collapse in the evolution of quantum entities. 展开更多
关键词 Orbital angular momentum Subluminal group velocity double slitsWave functions Physical reality
原文传递
Long-term rice-rice-green manure rotation changing the microbial communities in typical red paddy soil in South China 被引量:29
8
作者 GAO Song-juan ZHANG Ren-gang +8 位作者 CAO Wei-dong FAN Yuan-yuan GAO Ju-sheng HUANG Jing BAI Jin-shun ZENG Nao-hua CHANG Dan-na Shimizu Katsu-yoshi Kristian Thorup-Kristensen 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第12期2512-2520,共9页
On the basis of a long-term(30 years) field experiment that involved four rotation systems, rice-rice-winter fallow(RRF), rice-rice-ryegrass(RRG), rice-rice-rape(RRP), and rice-rice-milk vetch(RRV), this stu... On the basis of a long-term(30 years) field experiment that involved four rotation systems, rice-rice-winter fallow(RRF), rice-rice-ryegrass(RRG), rice-rice-rape(RRP), and rice-rice-milk vetch(RRV), this study described the effects of green manure on the microbial communities in the red paddy soils using 454 pyrosequencing for the 16 S r RNA gene. The Chao1 richness and non-parametric Shannon's index increased in all soil samples that received green manure treatments. The communities' structures with the green manure applications were significantly dissimilar from that under the winter fallow. Using Metastats tests, many genera in the RRG, RRP and RRV soils were significantly different from those in the RRF soil, including a number of genera that functioned in the nitrogen and sulfur cycles. Analyses of the genera with these functions revealed the shifts in microbial ecosystem functions after long-term green manuring. Changes in the microbial communities increased the ammonium supply and decreased the soil acidification in green-manure-amended soils. Together, these data suggested powerful effects of green manure on both the microbial communities and the biogeochemical cycle driven by the shifts in bacterial functional groups. 展开更多
关键词 green manure community structure community function 16S rRNA gene double rice
下载PDF
A compact model for single material double work function gate MOSFET
9
作者 郑长勇 张伟 +2 位作者 徐太龙 代月花 陈军宁 《Journal of Semiconductors》 EI CAS CSCD 2013年第9期58-62,共5页
An analytical surface potential model for the single material double work function gate (SMDWG) MOSFET is developed based on the exact resultant solution of the two-dimensional Poisson equation. The model includes t... An analytical surface potential model for the single material double work function gate (SMDWG) MOSFET is developed based on the exact resultant solution of the two-dimensional Poisson equation. The model includes the effects of drain biases, gate oxide thickness, different combinations of S-gate and D-gate length and values of substrate doping concentration. More attention has been paid to seeking to explain the attributes of the SMDWG MOSFET, such as suppressing drain-induced barrier lowering (DIBL), accelerating carrier drift velocity and device speed. The model is verified by comparison to the simulated results using the device simulator MEDICI. The accuracy of the results obtained using our analytical model is verified using numerical simulations. The model not only offers the physical insight into device physics but also provides the basic designing guideline for the device. 展开更多
关键词 analytical model surface potential single material double work function gate (SMDWG) MOSFET simulation DIBL
原文传递
On Functional Relations for the Alternating Analogues of Tornheim's Double Zeta Function
10
作者 Zhonghua LI 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2015年第6期907-918,共12页
In this paper,new proofs of two functional relations for the alternating analogues of Tornheim's double zeta function are given.Using the functional relations,the author gives new proofs of some evaluation formula... In this paper,new proofs of two functional relations for the alternating analogues of Tornheim's double zeta function are given.Using the functional relations,the author gives new proofs of some evaluation formulas found by Tsumura for these alternating series. 展开更多
关键词 Tornheim's double zeta function Riemann zeta function functional relations
原文传递
Density functional theory study on the influence of cation ratio on the host layer structure of Zn/Al double hydroxides 被引量:1
11
作者 Hong Yan Min Wei +1 位作者 Jing Ma Xue Duan 《Particuology》 SCIE EI CAS CSCD 2010年第3期212-220,共9页
A density functional theory (DFT) study has been carried out for [Zn-1AI(OH2)n+6(OH)2n-2]^3+ (n=3-6) and [Znn-1AI(OH2)2n-2(OH)2n-2]^3+ (n = 7) clusters, which include the basic structural information ... A density functional theory (DFT) study has been carried out for [Zn-1AI(OH2)n+6(OH)2n-2]^3+ (n=3-6) and [Znn-1AI(OH2)2n-2(OH)2n-2]^3+ (n = 7) clusters, which include the basic structural information of the brucite-like lattice structure of Zn/Al layered double hydroxides (LDHs) with Zn/AI molar ratio (R) in the range 2-6, in order to understand the effect of the Zn/Al ratio on the structure and stability of binary Zn/Al LDHs. Based on systematic calculations of the geometric parameters and formation energies of the cluster models, it was found that it is possible for Zn^2+ and Al^3+ cations to replace Mg^2+ isomorphously in the brucite-like structure with different R values, resulting in differences in microstructure of the clusters and unit cell parameter a of the Zn/Al LDHs. Analysis of the geometry and bonding around the trivalent Al^3+ or divalent Zn^2+ cations reveals that Al^3+ plays a more significant role than Zn^2+ in determining the microstructure properties, formation and bonding stability of the corresponding ZnRAl clusters when R〈5, while the influence of Zn^2+ becomes the dominant factor in the case of R〉 5. These findings are in good agreement with experiments. This work provides a detailed electronic-level understanding of how the composition of cations affects the microstructure and stability of Zn-containing binary LDH layers. 展开更多
关键词 Layered double hydroxide Zn/Al molar ratio Density functional calculation Microstructure Formation and bonding stability
原文传递
A new recursive method for the analysis of linear time invariant dynamic systems via double-term triangular functions (DTTF) in state space environment
12
作者 Anish DEB Suchismita GHOSH +1 位作者 Srimanti Roy CHOUDHURY Gautam SARKAR 《控制理论与应用(英文版)》 EI CSCD 2013年第1期108-115,共8页
This paper presents a new recursive method for system analysis via double-term triangular functions (DTTF) in state space environment. The proposed method uses orthogonal triangular function sets and proves to be mo... This paper presents a new recursive method for system analysis via double-term triangular functions (DTTF) in state space environment. The proposed method uses orthogonal triangular function sets and proves to be more accurate as compared to single term Walsh series (STWS) method with respect to mean integral square error (MISE). This has been established theoretically and comparison of error with respect to MISE is presented for clarity. A numerical example is treated to establish the proposed method. Relevant curves for the solutions of states of the dynamic system are also presented with plots of percentage error for DTTF-based analysis. 展开更多
关键词 double term triangular functions Walsh functions System analysis Single term Walsh series Mean integral square error (MISE)
原文传递
Dynamic constitutive model for soils considering asymmetry of skeleton curve
13
作者 Guoxing Chen Hua Pan +1 位作者 Hui Long Xiaojun Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2013年第5期400-405,共6页
Based on the asymmetric characteristic of skeleton curve obtained from dynamic tests on soils,a function with double asymptotes is proposed for describing the dynamic constitutive relations of soils.The hysteresis loo... Based on the asymmetric characteristic of skeleton curve obtained from dynamic tests on soils,a function with double asymptotes is proposed for describing the dynamic constitutive relations of soils.The hysteresis loops observed during unloading and reloading show the same form as the skeleton curve and are constructed by taking the ultimate stress as the corresponding asymptote.The coeffcient of initial unloading modulus is used to ensure that the constructed hysteresis loop fts well with the experimental data.Then,a new dynamic constitutive model considering the asymmetry of skeleton curve is elaborated.The verifcation tests on saturated Nanjing fne sand are performed using a hollow cylinder apparatus to verify the applicability of the UD model.It is found that the predicted curves by the UD model agree well with the test data. 展开更多
关键词 function with double asymptotes Dynamic constitutive model Shear modulus Damping ratio Complex initial stress state
下载PDF
Fabrication of Zn-Ti layered double hydroxide by varying cationic ratio of Ti^(4+) and its application as UV absorbent 被引量:5
14
作者 Xin-Rui Wang Yong Li +4 位作者 Li-Ping Tang Wen Gan Wei Zhou Yu-Fei Zhao Dong-Sheng Bai 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第2期394-399,共6页
ZnTi-layered double hydroxides(LDHs) with varying Zn/Ti ratio have been synthesized by coprecipitation of zinc and titanium salts from homogeneous solution.The obtained ZnTi-LDHs possess high crystallinity and hiera... ZnTi-layered double hydroxides(LDHs) with varying Zn/Ti ratio have been synthesized by coprecipitation of zinc and titanium salts from homogeneous solution.The obtained ZnTi-LDHs possess high crystallinity and hierarchical structure with improved UV-absorbance property.The UV-vis spectra show that the UV absorbing properties of ZnTi-LDHs is stronger and broader than both MgAl-LDH and ZnAl-LDH due to the existence of Ti.Moreover,the UV absorption property increased with the content of Ti,which can be ascribed to the decrease in the band gap energy,as clearly confirmed by density functional theory calculations.When irradiated by UV rays,the property of the samples with generated free radicals(OH^·and O2^·) was evaluated by means of electron spin resonance(EPR).ZnTi-LDHs generated a relatively lower active radicals in contrast with TiO2 and ZnO,which implied an increased safety used as sunscreens.Therefore,this work provides a detailed understanding of UV shielding properties of ZnTiLDHs which was unrevealed previously,and demonstrates the expansive application prospects of ZnTiLDHs in the field of sunscreens. 展开更多
关键词 Layered double hydroxide UV absorbent Density functional theory calculations Photoactivity Band gap
原文传递
A discussion on the double wave theory and its applications to description of radiation atoms
15
作者 梁方豪 《Science China Mathematics》 SCIE 2001年第3期402-408,共7页
The double wave theory (DWT), sometimes called the“non_statistical quantum mechanics” by its proposer, describes the state of each single particle in an ensemble with two wave functions which have a parameter corres... The double wave theory (DWT), sometimes called the“non_statistical quantum mechanics” by its proposer, describes the state of each single particle in an ensemble with two wave functions which have a parameter corresponding to the particle. However the basic postulates of the DWT show that this theory can hardly describe any quantum rules of the microscopic world. In the double wave descriptions, the wave feature of the behavior of microscopic particles and the discontinuity characteristic of energy almost disappear. The discussions on several problems of the radiation atoms made by the DWT's proposer on the basis of this theory are either mathematically incorrect or inconsistent with experiments and the usual theory. 展开更多
关键词 double wave functions particle ensemble single particle result of measurement of physical quantity double wave theory (DWT)
原文传递
Velocity Preset and Transitional Zone′s Shape Optimization for Tailor Rolled Blank 被引量:3
16
作者 Dong-cheng WANG Lian-chao DONG +1 位作者 Hong-min LIU Yan WANG 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2015年第4期279-287,共9页
Tailor rolled blank (TRB) is a type of emerging material to produce lightweight vehicle parts. Transitional zoners shape is an important parameter for tailor rolled blank. It not only affects mold design and the loc... Tailor rolled blank (TRB) is a type of emerging material to produce lightweight vehicle parts. Transitional zoners shape is an important parameter for tailor rolled blank. It not only affects mold design and the local carrying capacity of the stamping parts, but also determines the maximum value and variation characteristics of rolling force. How to get the best transitional zone's shape is a key problem for production of tailor rolled blank. A double power function is put forward using for transitional curve, which is continuous and smooth at all connection points inde- pendent of its parameters, so the sudden change of mechanical parameters during rolling and forming process can be avoided. At the same time, the velocity formula and restriction for arbitrary transitional curve are derived to preset vertical velocity of the roller and judge whether the curve can be rolled successfully or not. Then, the finite element method (FEM) is used to verify the precision of velocity formula and study the mechanical characteristics of different curves. Finally, a method to obtain the optimal curve equation is put forward and verified. 展开更多
关键词 tailor rolled blank transitional zone double power function velocity preset shape optimization
原文传递
Airframe Damage Region Division Method Based on Structure Tensor Dynamic Operator
17
作者 CAI SHUYU SHI LIZHONG 《Journal of Shanghai Jiaotong university(Science)》 EI 2022年第6期757-767,共11页
In order to improve the accuracy of damage region division and eliminate the interference of damage adjacent region,the airframe damage region division method based on the structure tensor dynamic operator is proposed... In order to improve the accuracy of damage region division and eliminate the interference of damage adjacent region,the airframe damage region division method based on the structure tensor dynamic operator is proposed in this paper.The structure tensor feature space is established to represent the local features of damage images.It makes different damage images have the same feature distribution,and transform varied damage region division into consistent process of feature space division.On this basis,the structure tensor dynamic operator generation method is designed.It integrates with bacteria foraging optimization algorithm improved by defining double fitness function and chemotaxis rules,in order to calculate the parameters of dynamic operator generation method and realize the structure tensor feature space division.And then the airframe damage region division is realized.The experimental results on different airframe structure damage images show that compared with traditional threshold division method,the proposed method can improve the division quality.The interference of damage adjacent region is eliminated.The information loss caused by over-segmentation is avoided.And it is efficient in operation,and consistent in process.It also has the applicability to different types of structural damage. 展开更多
关键词 airframe damage region division dynamic operator structure tensor feature distribution double fitness function intelligent maintenance
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部