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加工中心编程的简化
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作者 马素玲 《辽宁师专学报(自然科学版)》 2007年第2期87-88,共2页
加工中心是利用程序控制的,而简化编程、缩短编程时间是提高加工效率的关键所在.以Sinumerik 880系统为例,具体说明利用R参数和功能函数@简化程序的方法.
关键词 加工中心 编程的简化 R参数 功能函数@
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Feature Extraction of Acoustic/Seismic Signal of Target 被引量:1
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作者 张中民 李科杰 +1 位作者 李贵涛 尚雅玲 《Journal of Beijing Institute of Technology》 EI CAS 2000年第3期312-317,共6页
A microphone and a seismic sensor always become a basic unit of UGS(unattended ground sensors) system. The mechanism of acoustic and seismic property of target and its propagation are described. The acoustic and seism... A microphone and a seismic sensor always become a basic unit of UGS(unattended ground sensors) system. The mechanism of acoustic and seismic property of target and its propagation are described. The acoustic and seismic signals of targets are analyzed with time frequency distribution according to its non stationary property. Narrow band energy function (NEF) and local power spectral density (LPSD) are proposed to extract features for target identification. Experiment results show that local power spectral density indicates corresponding target clearly. 展开更多
关键词 time frequency analysis narrow band energy function (NEF) local power spectral density(LPSD)
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Elastic and Thermodynamic Properties of CdSe from First-Principles Calculations 被引量:3
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作者 TAN Jia-Jin CHENG Yan +1 位作者 ZHU Wen-Jun GOU Qing-Quan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期220-226,共7页
The lattice parameters, bulk modulus, phase transition pressure, and temperature dependencies of the elastic constants cij of CdSe are investigated by using the Cambridge Serial Total Energy Package (CASTEP) program... The lattice parameters, bulk modulus, phase transition pressure, and temperature dependencies of the elastic constants cij of CdSe are investigated by using the Cambridge Serial Total Energy Package (CASTEP) program in the frame of Density Functional Theory (DFT). It is found that the phase transitions from the ZB structure to the RS structure and from WZ structure to RS structure are 2.2 GPa and 2.8 GPa, respectively. Our results agree well with the available experimental data and other theoretical results. The aggregate elastic modulus (B, G, E, A ), the Poisson's ratio (v), the Griuneisen parameter (γ), the Debye temperature θD on pressure and temperature are also successfully obtained. 展开更多
关键词 elastic properties thermodynamic properties density functional theory CDSE
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Neural network modeling and control of proton exchange membrane fuel cell 被引量:1
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作者 陈跃华 曹广益 朱新坚 《Journal of Central South University of Technology》 EI 2007年第1期84-87,共4页
A neural network model and fuzzy neural network controller was designed to control the inner impedance of a proton exchange membrane fuel cell (PEMFC) stack. A radial basis function (RBF) neural network model was trai... A neural network model and fuzzy neural network controller was designed to control the inner impedance of a proton exchange membrane fuel cell (PEMFC) stack. A radial basis function (RBF) neural network model was trained by the input-output data of impedance. A fuzzy neural network controller was designed to control the impedance response. The RBF neural network model was used to test the fuzzy neural network controller. The results show that the RBF model output can imitate actual output well, the maximal error is not beyond 20 m-, the training time is about 1 s by using 20 neurons, and the mean squared errors is 141.9 m-2. The impedance of the PEMFC stack is controlled within the optimum range when the load changes, and the adjustive time is about 3 min. 展开更多
关键词 proton exchange membrane fuel cell radial basis function neural network fuzzy neural network
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A continuous differentiable wavelet threshold function for speech enhancement 被引量:3
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作者 贾海蓉 张雪英 白静 《Journal of Central South University》 SCIE EI CAS 2013年第8期2219-2225,共7页
Enhanced speech based on the traditional wavelet threshold function had auditory oscillation distortion and the low signal-to-noise ratio (SNR). In order to solve these problems, a new continuous differentiable thresh... Enhanced speech based on the traditional wavelet threshold function had auditory oscillation distortion and the low signal-to-noise ratio (SNR). In order to solve these problems, a new continuous differentiable threshold function for speech enhancement was presented. Firstly, the function adopted narrow threshold areas, preserved the smaller signal speech, and improved the speech quality; secondly, based on the properties of the continuous differentiable and non-fixed deviation, each area function was attained gradually by using the method of mathematical derivation. It ensured that enhanced speech was continuous and smooth; it removed the auditory oscillation distortion; finally, combined with the Bark wavelet packets, it further improved human auditory perception. Experimental results show that the segmental SNR and PESQ (perceptual evaluation of speech quality) of the enhanced speech using this method increase effectively, compared with the existing speech enhancement algorithms based on wavelet threshold. 展开更多
关键词 continuous differentiable wavelet threshold fimction speech enhancement Bark wavelet packet non-fixed deviation noise
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Two-Variable Hermite Polynomial Excitation of Two-Mode Squeezed Vacuum State as Squeezed Two-Mode Number State 被引量:1
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作者 HU Li-Yun FAN Hong-Yi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第10期965-970,共6页
We find that the squeezed two-mode number state is just a two-variable Hermite polynomial excitation of thetwo-mode squeezed vacuum state (THPES).We find that the Wigner function of THPES and its marginal distribution... We find that the squeezed two-mode number state is just a two-variable Hermite polynomial excitation of thetwo-mode squeezed vacuum state (THPES).We find that the Wigner function of THPES and its marginal distributionsare just related to two-variable Hermite polynomials (or Laguerre polynomials) and that the tomogram of THPES canbe expressed by one-mode Hermite polynomial. 展开更多
关键词 Two variable Hermite polynomial excitation state Wigner function marginal distribution tomgram
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IR study on surface chemical properties of catalytic grown carbon nanotubes and nanofibers 被引量:1
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作者 Li-hua TENG Tian-di TANG 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第5期720-726,共7页
In this study, the surface chemical properties of carbon nanotubes (CNTs) and carbon nanofibers (CNFs) grown by catalytic decomposition of methane on nickel and cobalt based catalysts were studied by DRIFT (Diffuse Re... In this study, the surface chemical properties of carbon nanotubes (CNTs) and carbon nanofibers (CNFs) grown by catalytic decomposition of methane on nickel and cobalt based catalysts were studied by DRIFT (Diffuse Reflectance Infrared Fourier Transform) and transmission Infrared (IR) spectroscopy. The results show that the surface exists not only carbon-hydrogen groups, but also carboxyl, ketene or quinone (carbonyl) oxygen-containing groups. These functional groups were formed in the process of the material growth, which result in large amount of chemical defect sites on the walls. 展开更多
关键词 Carbon nanotubes (CNTs) Carbon nanofibers (CNFs) Functional surface groups Infrared (IR) spectroscopy
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Optimality of Vector Optimization Involving Generalized Type-I Functions in Banach 被引量:1
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作者 QU He-mei XUE Zhen-xia 《Chinese Quarterly Journal of Mathematics》 CSCD 2009年第4期543-550,共8页
In this note,new classes of generalized type-I functions are introduced for functions between Banach spaces.These generalized type-I functions are then utilized to establish sufficient optimality conditions and dualit... In this note,new classes of generalized type-I functions are introduced for functions between Banach spaces.These generalized type-I functions are then utilized to establish sufficient optimality conditions and duality results for a vector optimization problem with functions defined on a Banach space. 展开更多
关键词 vector optimization optimality conditions type-I functions duality
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Improved plane layout of stabilizing piles based on the piecewise function expression of the irregular driving force 被引量:3
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作者 LIU Wen-qiang LI Qun +3 位作者 LU Jian LI Chang-dong YAO Wen-min ZENG Jiang-bo 《Journal of Mountain Science》 SCIE CSCD 2018年第4期871-881,共11页
The paper presents an improved plane layout for stabilizing piles based on a proposed piecewise function expression for the irregular driving force. Based on the specific morphological characteristics of a highway lan... The paper presents an improved plane layout for stabilizing piles based on a proposed piecewise function expression for the irregular driving force. Based on the specific morphological characteristics of a highway landslide, the piecewise function is used to calculate the irregular driving force by dividing the landslide into several sub-areas.Furthermore, the reasonable layout range and pile spacing can be obtained based on the piecewise function expression of the irregular driving force and on relevant research results of the plane layout for stabilizing piles. Therefore, an improved plane layout of stabilizing piles is presented in consideration of a piecewise function expression of the irregular driving force. A highway landslide located in eastern Guizhou Province, China, is analyzed as a case study using the proposed method. The results demonstrate that the theory presented in this paper provides improved economic benefits and can reduce the requirednumber of stabilizing piles by 28.6% compared with the conventional plane layout scheme. 展开更多
关键词 Highway landslide Driving force Piecewise function Stabilizing pile Plane layout
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Accuracy improvement of geometric correction for CHRIS data
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作者 WANG Dian-zhong PANG Yong GUO Zhi-feng 《Journal of Forestry Research》 SCIE CAS CSCD 2008年第3期260-262,共3页
This paper deals with a new type of multi-angle remotely sensed data--CHRIS(the Compact High Resolution Imaging Spec-trometer),by using rational function models(RFM)and rigorous sensor models(RSM).For ortho-rectifying... This paper deals with a new type of multi-angle remotely sensed data--CHRIS(the Compact High Resolution Imaging Spec-trometer),by using rational function models(RFM)and rigorous sensor models(RSM).For ortho-rectifying an image set,a rigorous sen-sor model-Toutin's model was employed and a set of reported parameters including across track angle,along track angle,IFOV,altitude,period,eccentricity and orbit inclination were input,then,the orbit calculation was started and the track information was given to the raw data.The images were ortho-rectified with geocoded ASTER images and digital elevation(DEM)data.Results showed that with 16 ground control points(GCPs),the correction accuracy decreased with view zenith angle,and the RMSE value increased to be over one pixel at 36 degree off-nadir.When the GCPs were approximately chosen as in Toutin's model,a RFM with three coefficients produced the same accuracy trend versus view zenith angle while the RMSEs for all angles were improved and within about one pixel. 展开更多
关键词 CHRIS ortho-rectify rigorous sensor model rational function model
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Design of similarity measure for discrete data and application to multi-dimension 被引量:1
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作者 LEE Myeong-ho 魏荷 +2 位作者 LEE Sang-hyuk LEE Sang-min SHIN Seung-soo 《Journal of Central South University》 SCIE EI CAS 2013年第4期982-987,共6页
Similarity measure design for discrete data group was proposed. Similarity measure design for continuous membership function was also carried out. Proposed similarity measures were designed based on fuzzy number and d... Similarity measure design for discrete data group was proposed. Similarity measure design for continuous membership function was also carried out. Proposed similarity measures were designed based on fuzzy number and distance measure, and were proved. To calculate the degree of similarity of discrete data, relative degree between data and total distribution was obtained. Discrete data similarity measure was completed with combination of mentioned relative degrees. Power interconnected system with multi characteristics was considered to apply discrete similarity measure. Naturally, similarity measure was extended to multi-dimensional similarity measure case, and applied to bus clustering problem. 展开更多
关键词 similarity measure MULTI-DIMENSION discrete data relative degree power interconnected system
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Weierstrass Elliptic Function Solutions to Nonlinear Evolution Equations
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作者 YU Jian-Ping SUN Yong-Li 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期295-298,共4页
This paper is based on the relations between projection Riccati equations and Weierstrass elliptic equation, combined with the Groebner bases in the symbolic computation.Then the novel method for constructing the Weie... This paper is based on the relations between projection Riccati equations and Weierstrass elliptic equation, combined with the Groebner bases in the symbolic computation.Then the novel method for constructing the Weierstrass elliptic solutions to the nonlinear evolution equations is given by using the above relations. 展开更多
关键词 nonlinear evolution equations Weierstrass elliptic function solutions Groebner bases
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Properties of Fuzzy Entropy Based on the Shape Change of Membership Function
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作者 卿铭 秦应兵 《Journal of Donghua University(English Edition)》 EI CAS 2007年第2期268-271,共4页
Modification of a fuzzy partition often leads to the change of fuzziness of a fuzzy system. Researches on the change of fuzzy entropy of a fuzzy set, responding to shape alteration of membership function, therefore... Modification of a fuzzy partition often leads to the change of fuzziness of a fuzzy system. Researches on the change of fuzzy entropy of a fuzzy set, responding to shape alteration of membership function, therefore, play a significant role in analysis of the change of fuzziness of a fuzzy system because a fuzzy partition consists of a set of fuzzy sets which satisfy some special constraints. This paper has shown several results about entropy changes of a fuzzy set. First, the entropies of two same type of fuzzy sets have a constant proportional relationship which depends on the ratio of the sizes of their support intervals. Second, as for Triangular Fuzzy Numbers (TFNs), the entropies of any two TFNs which can not be always the same type, also, have a constant proportional relationship which depends on the ratio of the sizes of their support intervals. Hence, any two TFNs with the same sizes of support intervals have the same entropies. Third, concerning two Triangular Fuzzy Sets (TFSs) with same sizes of support intervals and different heights, the relationship of their entropies lies on their height. Finally, we point it out a mistake that Chen's assertion that the entropy of resultant fuzzy set of elevation operation is directly to that of the original one while elevation factor just acts as a propartional factor. These results should contribute to the analysis and design of a fuzzy system. 展开更多
关键词 fuzzy entropy membership function entropy function triangular fuzzy number support interval
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Service Function Chain Orchestration across Multiple Clouds 被引量:1
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作者 Xuxia Zhong Ying Wang Xuesong Qiu 《China Communications》 SCIE CSCD 2018年第10期99-116,共18页
Network function virtualization is a new network concept that moves network functions from dedicated hardware to software-defined applications running on standard high volume severs. In order to accomplish network ser... Network function virtualization is a new network concept that moves network functions from dedicated hardware to software-defined applications running on standard high volume severs. In order to accomplish network services, traffic flows are usually processed by a list of network functions in sequence which is defined by service function chain. By incorporating network function virtualization in inter-data center(DC) network, we can use the network resources intelligently and deploy network services faster. However, orchestrating service function chains across multiple data centers will incur high deployment cost, including the inter-data center bandwidth cost, virtual network function cost and the intra-data center bandwidth cost. In this paper, we orchestrate SFCs across multiple data centers, with a goal to minimize the overall cost. An integer linear programming(ILP) model is formulated and we provide a meta-heuristic algorithm named GBAO which contains three modules to solve it. We implemented our algorithm in Python and performed side-by-side comparison with prior algorithms. Simulation results show that our proposed algorithm reduces the overall cost by at least 21.4% over the existing algorithms for accommodating the same service function chain requests. 展开更多
关键词 network function virtualization service function chain orchestration inter-DC network
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A new escape time algorithm of constructing Julia set
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作者 袁杰 Li Xiali +1 位作者 Hou Zhiling Cao Maosheng 《High Technology Letters》 EI CAS 2007年第2期194-197,共4页
Escape time algorithm is an effective theoretical algorithm of constructing fractal graphics. The key of this algorithm lies in the construction of escape time function. A new escape time function is presented based o... Escape time algorithm is an effective theoretical algorithm of constructing fractal graphics. The key of this algorithm lies in the construction of escape time function. A new escape time function is presented based on the research of escape time algorithm. An accelerated escape time algorithm is carried out in this paper. The experiments have demonstrated that the new algorithm is not only as precise as the old, but also faster when it is used to construct Julia set. 展开更多
关键词 FRACTAL escape time algorithm escape time function Julia set
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Augmented Kierlik-Rosinberg Fundamental Measure Functional and Extension of Fundamental Measure Functional to Inhomogeneous Non-hard Sphere Fluids
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作者 周世琦 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第12期1023-1039,共17页
From point of view of weighted density procedure, it is guessed that a Percus-Yevick (PY) compressibility excess free energy density, appearing in the Kierlik Rosinberg type fundamental measure functional (KR-FMF)... From point of view of weighted density procedure, it is guessed that a Percus-Yevick (PY) compressibility excess free energy density, appearing in the Kierlik Rosinberg type fundamental measure functional (KR-FMF) and expressed in terms of scaled particle variables, can be substituted by a corresponding expression dictated by a more accurate Mansoori Carnahan-Starling Leland (MCSL) equation of state, while retaining the original weighting functions; it is numerically indicated that the resultant undesirable non-self-consistency between the PY type weighting function and MCSL type excess free energy density had no bad effect on the performance of the resultant augmented KR-ffMF which, on the one hand, preserves the exact low-density limit of the original KR-FMF and holds a high degree of pressure self-consistency, on the other hand, improves significantly, as expected, the predictions of density profile of hard sphere fluid at single hard wall contact location and its vicinity, and of the bulk hard sphere second order direct correlation function (DCF), obtained from functional differentiation. The FMF is made applicable to inhomogeneous non-hard sphere fluids by supplementing a functional perturbation expansion approximation truncated at the lowest order with summation of higher order terms beyond the lowest term calculated by the FMF for an effective hard sphere fluid; the resultant extended FMF only needs second order DCF and pressure of the fluid considered at coexistence state as inputs, consequently is applicable whether the considered temperature is above critical point or below critical point. The extended MCSL-augmented KR-FMF is found to be endowed with an excellent performance for predictions of density profile and surface tension by comparing the present predictions of these two quantities with available computer simulation data for inhomogeneous hard core attractive Yukawa fluid and Lennard-3ones fluid. 展开更多
关键词 density functional theory
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Correct Path-Integral Formulation of Quantum Thermal Field Theory in Coherent State Representation
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作者 SUJun-Chen ZHENGFu-Hou 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第4期641-656,共16页
The path-integral quantization of thermal scalar, vector, and spinor fields is performed newly in the coherent-state representation. In doing this, we choose the thermal electrodynamics and psi(4) theory as,examples. ... The path-integral quantization of thermal scalar, vector, and spinor fields is performed newly in the coherent-state representation. In doing this, we choose the thermal electrodynamics and psi(4) theory as,examples. By this quantization, correct expressions of the partition functions and the generating functionals for the quantum thermal electrodynamics and psi(4) theory are obtained in the coherent-state representation. These expressions allow us to perform analytical calculations of the partition functions and generating functionals and therefore are useful in practical applications. Especially, the perturbative expansions of the generating functionals are derived specifically by virtue of the stationary-phase method. The generating functionals formulated in the position space are re-derived from the ones given in the coherent-state representation. 展开更多
关键词 thermal fields partition function generating functional coherent-state representation
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Algebraic attacks on two kinds of special nonlinear filter generators
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作者 杨文峰 Hu Yupu Qiu Hua 《High Technology Letters》 EI CAS 2012年第2期151-154,共4页
This letter proposes algebraic attacks on two kinds of nonlinear filter generators with symmetric Boolean functions as the filter fimctions. Different fxom the classical algebraic attacks, the proposed attacks take th... This letter proposes algebraic attacks on two kinds of nonlinear filter generators with symmetric Boolean functions as the filter fimctions. Different fxom the classical algebraic attacks, the proposed attacks take the advantage of the combinational property of a linear feedback shift register (LFSR) and the symmetric Boolean function to obtain a tow-degree algebraic relation, and hence the complexities of the proposed attacks are independent of the algebraic immunity (AI) of the filter functions. It is shown that improper combining of the LFSR with the filter function can make the filter generator suffer from algebraic attacks. As a result, the bits of the LFSR must be selected properly to input the filter function with large AI in order to withstand the proposed algebraic attacks. 展开更多
关键词 stream cipher linear feedback shift register (LFSR) Boolean function algebraic attack CRYPTANALYSIS
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Key Technology Analysis for Driver Support Systems in Japan
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作者 Hiroshi Takahashi 《Computer Technology and Application》 2013年第4期212-222,共11页
This paper presents the technical survey and the trend analysis of the driver support technologies such as a pre-crush braking system in Japan. In the first part, Vehicle Intelligence to assist drivers is defined by t... This paper presents the technical survey and the trend analysis of the driver support technologies such as a pre-crush braking system in Japan. In the first part, Vehicle Intelligence to assist drivers is defined by two objective functions which are both TGA (Target Generation Agent) and TAA (Target Accomplishment Agent). TAA is mainly based on the conventional technologies that are braking smoothly, or driving with lower fuel consumption. On the other hand, TGA has the intelligent function instead of human drivers. The actual TGA are explained using some concrete driver support systems. After that, Japanese market introduction date and evolution of driver support systems are discussed with clarifying cognitive aspects which are the perception support, the judgment support and the execution support. And Key technologies underlying evolution of driver support systems are explained. Finally the author concludes that the knowledge and insights needed for intelligent driver support systems will be much more complex than in the case of autonomous vehicles that drive themselves. 展开更多
关键词 Driver support systems driver-vehicle interaction intelligent transport systems.
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HIGH EMISSION PERFORMANCE IMPREGNATED DISPENSER CATHODE
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作者 Yin Shengyi Peng Zhen +1 位作者 Zheng Qiang Wang Yu 《Journal of Electronics(China)》 2013年第4期417-422,共6页
In order to obtain higher emission performance than that of a traditional M-type cathode, we have developed a new type impregnated dispenser cathode. The new cathode is impregnated with a new active substance with mol... In order to obtain higher emission performance than that of a traditional M-type cathode, we have developed a new type impregnated dispenser cathode. The new cathode is impregnated with a new active substance with molar ratio of 26BaO·29SrO·8Sc2O3 ·7CaO·Al2O3 . This paper introduces the emission performance, surface active material, and work function of the new cathode. At 1100℃B , the DC current density and pulse current density are 30.6±1.0 A/cm2 and 171.6±2.8 A/cm2 , respectively, 2.1 and 5.4 times of that of an M-type cathode. The work function of the new cathode is 1.668± 0.002 eV. High concentration O-Al-Sc-Sr-Ba and O-Al-Sc-Ba are found in the pores and at pore edges, respectively. By comparing the emission performances and surface characteristics of as-polished and as-cleaned cathodes, it is proposed that, the emission around pore ends forms the major part of the total emission for the new cathodes. 展开更多
关键词 Dispenser cathode M-type cathode Sc2O3 SRO Emission performance
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