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Research on the Development of the Grade Point Average System in Higher Education-Re-understand the Connotation and Function of GPA
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作者 Wenxiu Zhang 《Journal of Contemporary Educational Research》 2025年第9期225-231,共7页
With the continuous advancement of the internationalization of higher education in China,the Grade Point Average(GPA)has become a primary indicator for evaluating academic performance in universities,playing a positiv... With the continuous advancement of the internationalization of higher education in China,the Grade Point Average(GPA)has become a primary indicator for evaluating academic performance in universities,playing a positive role in educational management.However,as it is closely tied to students’immediate interests,such as awards,exemptions from entrance exams for postgraduate recommendations,and domestic or international further education,certain new issues have emerged in its practical application.These problems have hindered the effective functioning of the GPA system,attracting widespread attention.This paper examines the origin,connotation,and theoretical assumptions of the GPA system,discusses its positive functions and existing challenges,and proposes recommendations for further improving academic evaluation. 展开更多
关键词 Point system Grade point average(GPA) Academic evaluation Educational management
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Fixed-time distributed average consensus tracking for multiple Euler-Lagrange systems
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作者 SUN Guhao ZENG Qingshuang CAI Zhongze 《Journal of Systems Engineering and Electronics》 2025年第2期523-536,共14页
This paper investigates the sliding-mode-based fixed-time distributed average tracking (DAT) problem for multiple Euler-Lagrange systems in the presence of external distur-bances. The primary objective is to devise co... This paper investigates the sliding-mode-based fixed-time distributed average tracking (DAT) problem for multiple Euler-Lagrange systems in the presence of external distur-bances. The primary objective is to devise controllers for each agent, enabling them to precisely track the average of multiple time-varying reference signals. By averaging these signals, we can mitigate the influence of errors and uncertainties arising dur-ing measurements, thereby enhancing the robustness and stabi-lity of the system. A distributed fixed-time average estimator is proposed to estimate the average value of global reference sig-nals utilizing local information and communication with neigh-bors. Subsequently, a fixed-time sliding mode controller is intro-duced incorporating a state-dependent sliding mode function coupled with a variable exponent coefficient to achieve dis-tributed average tracking of reference signals, and rigorous ana-lytical methods are employed to substantiate the fixed-time sta-bility. Finally, numerical simulation results are provided to vali-date the effectiveness of the proposed methodology, offering insights into its practical application and robust performance. 展开更多
关键词 distributed average tracking(DAT) fixed-time con-vergence Euler-Lagrange systems sliding mode control
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Average recurrence intervals of strong earthquakes and potential risky segments along the Taiyuan-Linfen portion of the Shanxi graben system 被引量:6
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作者 易桂喜 闻学泽 徐锡伟 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第4期426-437,共12页
Since the great 1303 Hongtong, Shanxi, earthquake of magnitude 8, 700 years have elapsed. To analyze the long-term seismic potential, this paper divides the Taiyuan-Linfen portion of the Shanxi graben system into 5 se... Since the great 1303 Hongtong, Shanxi, earthquake of magnitude 8, 700 years have elapsed. To analyze the long-term seismic potential, this paper divides the Taiyuan-Linfen portion of the Shanxi graben system into 5 seismogenic segments. Based on data of historical earthquakes and GPS observation, the authors estimate mean seismic-moment rates and average recurrence intervals of strong earthquakes for the individual segments, and fur-ther analyze relative levels of current stress cumulation on the segments based on mapping b-values along the gra-ben system by using the network seismic data for the recent over 30 years. The main result shows that the Linfen basin segment has an estimated mean seismic-moment rate of 2.211016 Nm/a to 3.031016 Nm/a, and its average recurrence interval for M=7.5 earthquake is estimated to be between 1 560 and 2 140 years. For the Ling-shi-Hongtong segment, the estimated average recurrence interval for M=8 earthquakes is between 4 300 and 5 100 years, equivalent to having a mean moment-rate of 2.581016 Nm/a to 3.101016 Nm/a. The contour map of b-values shows that the two segments of Lingshi-Hongtong and Linfen basin have been being at low or relatively low stress levels, reflecting that since the 1303 M=8 and the 1695 M=7.5 earthquake ruptures, the fault-planes strengths of the both segments have not been resumed yet. And the other two segments, the Houma and the Jiexiu-Fenyang, have relatively high stress levels, and have been already identified as potential risky segments for the coming earthquakes from the analysis combining with the estimated average recurrence intervals of earth-quakes on the both segments. 展开更多
关键词 historical earthquakes seismogenic segment moment rate average recurrence interval poten-
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Average Capacity of OAM-Multiplexed FSO System with Vortex Beam Propagating Through Non-Kolmogorov Turbulence 被引量:4
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作者 Hua Tang Wei Xu Guohua Wu 《China Communications》 SCIE CSCD 2016年第10期153-159,共7页
The propagation of vortex beam in atmospheric turbulence is of significant importance in theoretical study and practical applications. Based on extended Huygens-Fresnel integral and the Rytov approximation, the averag... The propagation of vortex beam in atmospheric turbulence is of significant importance in theoretical study and practical applications. Based on extended Huygens-Fresnel integral and the Rytov approximation, the average capacity of orbital angular momentum(OAM)-multiplexed Laguerre-Gaussian(LG) beam propagating through non-Kolmogorov turbulence is presented, and the analytical expression of spiral spectrum of LG beam has been deduced. The average capacity of FSO system is numerically calculated and the influence of exponent parameter, transmission height, structure constant, wavelength, outer scale and inner scale on average capacity are also analyzed in detail. Outcomes show that smaller structure constant, outer scale, higher transmission height and larger wavelength, inner scale are conducive to improve average capacity in different extent. Results acquires in this paper have potential application value in optical communication within non-Kolmogorov turbulence. 展开更多
关键词 laguerre-gaussian beam non-kolmogorov turbulence multiple topological charges average capacity
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Stability of Switched Positive Descriptor Systems with Average Dwell Time Switching 被引量:2
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作者 夏彪 连捷 袁学海 《Journal of Shanghai Jiaotong university(Science)》 EI 2015年第2期177-184,共8页
In this paper, the problems of stability for a class of switched positive descriptor systems(SPDSs)with average dwell time(ADT) switching are investigated. First, based on the equivalent switched system and the proper... In this paper, the problems of stability for a class of switched positive descriptor systems(SPDSs)with average dwell time(ADT) switching are investigated. First, based on the equivalent switched system and the properties of the projector matrix, sufficient stabilities are given for the underlying systems in both continuoustime and discrete-time contexts. Then, a sufficient stability condition for the SPDS with both stable and unstable subsystems is obtained. The stability results for the SPDSs are represented in terms of a set of linear programmings(LPs) by the multiple linear co-positive Lyapunov function(MLCLF) approach. Finally, three numerical examples are given to illustrate the effectiveness of the obtained theoretical results. 展开更多
关键词 average dwell time(ADT) switched positive descriptor systems(SPDSs) linear programming(LP) STABILITY
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Average consensus of multi-agent systems with communication time delays and noisy links 被引量:1
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作者 孙永征 李望 阮炯 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第3期262-270,共9页
In this paper,we consider the average-consensus problem with communication time delays and noisy links.We analyze two different cases of coupling topologies:fixed and switching topologies.By utilizing the stability t... In this paper,we consider the average-consensus problem with communication time delays and noisy links.We analyze two different cases of coupling topologies:fixed and switching topologies.By utilizing the stability theory of the stochastic differential equations,we analytically show that the average consensus could be achieved almost surely with the perturbation of noise and the communication time delays even if the time delay is time-varying.The theoretical results show that multi-agent systems can tolerate relatively large time delays if the noise is weak,and they can tolerate relatively strong noise if the time delays are low.The simulation results show that systems with strong noise intensities yield slow convergence. 展开更多
关键词 average consensus multi-agent systems time delay white noise
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Semi-global weighted output average tracking of discrete-time heterogeneous multi-agent systems subject to input saturation and external disturbances 被引量:1
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作者 Qilin Song Yuanlong Li +1 位作者 Yijing Xie Zongli Lin 《Control Theory and Technology》 EI CSCD 2023年第3期315-333,共19页
In this paper,we revisit the semi-global weighted output average tracking problem for a discrete-time multi-agent system subject to input saturation and external disturbances.The multi-agent system consists of multipl... In this paper,we revisit the semi-global weighted output average tracking problem for a discrete-time multi-agent system subject to input saturation and external disturbances.The multi-agent system consists of multiple heterogeneous linear systems as leader agents and multiple heterogeneous linear systems as follower agents.We design both the state feedback and output feedback control protocols for each follower agent.In particular,a distributed state observer is designed for each follower agent that estimates the state of each leader agent.In the output feedback case,state observer is also designed for each follower agent to estimate its own state.With these estimates,we design low gain-based distributed control protocols,parameterized in a scalar low gain parameter.It is shown that,for any bounded set of the initial conditions,these control protocols cause the follower agents to track the weighted average of the outputs of the leader agents as long as the value of the low gain parameter is tuned sufficiently small.Simulation results illustrate the validity of the theoretical results. 展开更多
关键词 Distributed average tracking Input saturation Low gain feedback Heterogeneous multi-agent systems Output regulation
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WEIGHTED AVERAGE OF DIRICHLET KERNELS FOR VILENKIN-LIKE SYSTEM 被引量:1
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作者 张传洲 刘培德 《Acta Mathematica Scientia》 SCIE CSCD 2009年第1期45-55,共11页
For Vilenkin-like system, the authors define a new operator H*f := supn |Hnf|, where Hnf is the weighted average for partial sums, and prove that H* is of type (Hp* (Gm), Lp(Gm)) for all 1/2 < p ≤ ∞. As a consequ... For Vilenkin-like system, the authors define a new operator H*f := supn |Hnf|, where Hnf is the weighted average for partial sums, and prove that H* is of type (Hp* (Gm), Lp(Gm)) for all 1/2 < p ≤ ∞. As a consequence, the authors prove the operator S*f := supn |Snf| is of type (p, p) for 1 < p < ∞, where Snf is the n-partial sum. 展开更多
关键词 Martingale Hardy space Vilenkin-like systems weighted average
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A Low Complexity Linear Moving Average Filtering Technique for PAR Reduction in OFDM Systems 被引量:1
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作者 Hassan Ali Raziq Yaqub 《International Journal of Communications, Network and System Sciences》 2018年第10期199-215,共17页
In this paper, a linear moving average recursive filtering technique is proposed to reduce the peak-to-average power ratio (PAR) of orthogonal frequency division multiplexing (OFDM) signals. The proposed low complexit... In this paper, a linear moving average recursive filtering technique is proposed to reduce the peak-to-average power ratio (PAR) of orthogonal frequency division multiplexing (OFDM) signals. The proposed low complexity technique is analyzed in an oversampled OFDM system and a simple distribution approximation of the oversampled and linearly filtered OFDM signals is also proposed. Corresponding time domain linear equalizers are developed to recover originally transmitted data symbols. Through extensive computer simulations, effects of the new filtering technique on the oversampled OFDM peak-to-average power ratio (PAR), power spectral density (PSD) and corresponding linear equalizers on the frequency selective Rayleigh fading channel transmission symbol-error-rate (SER) performance are investigated. The newly proposed recursive filtering scheme results in attractive PAR reduction, requires no extra fast Fourier transform/inverse fast Fourier transform (FFT/IFFT) operations, refrains from transmitting any side information, and reduces out-of-band radiation. Also, corresponding linear receivers are shown to perform very close to their frequency domain counterparts. 展开更多
关键词 Moving average FILTERING RECURSIVE FILTERING Orthogonal Frequency Division MULTIPLEXING Peak-to-average-Power Ratio Inverse Fast FOURIER Transform
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A Protocol to Estimate the Average Fidelity of the Space-Separated Bipartite System
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作者 黄龙 吴小华 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第9期274-280,共7页
In present work, we show that the average fidelity of a bipartite system can be decided by the average survive probability of the product state and the average survive probability of each subsystem. Several protocols ... In present work, we show that the average fidelity of a bipartite system can be decided by the average survive probability of the product state and the average survive probability of each subsystem. Several protocols to measure these quantities are constructed. Our method is suitable for the cases where the bipartite system is space-separated. 展开更多
关键词 the average FIDELITY twirling QUANTUM process tomo
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The correlation between stochastic resonance and the average phase-synchronization time of a bistable system driven by colour-correlated noises
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作者 董小娟 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第1期136-142,共7页
This paper investigates the correlation between stochastic resonance (SR) and the average phase-synchronization time which is between the input signal and the output signal in a bistable system driven by colour-corr... This paper investigates the correlation between stochastic resonance (SR) and the average phase-synchronization time which is between the input signal and the output signal in a bistable system driven by colour-correlated noises. The results show that the output signal-to-noise ratio can reach a maximum with the increase of the average phase- synchronization time, which may be helpful for understanding the principle of SR from the point of synchronization; however, SR and the maximum of the average phase-synchronization time appear at different optimal noise level, moreover, the effects on them of additive and multiplicative noise are different. 展开更多
关键词 stochastic resonance phase-synchronization signal-to-noise ratio average phase- synchronization time
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Regional averaged controllability for hyperbolic parameter dependent systems
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作者 Mouna ABDELLI Abdelhak HAFDALLAH +1 位作者 Faycal MERGHADI Meriem LOUAFI 《Control Theory and Technology》 EI CSCD 2020年第3期307-314,共8页
The purpose of this paper is to extend the notion of regional controllability for hyperbolic parameter dependent systems.The key idea is the characterization of the averaged regional control with minimal energy.This c... The purpose of this paper is to extend the notion of regional controllability for hyperbolic parameter dependent systems.The key idea is the characterization of the averaged regional control with minimal energy.This control steers the state average(with respect to such a parameter)towards the desired state only on a given part of the system evolution domain.In this paper,we give the precis definition and the properties of this new concept.Then,we use an approach based on an extension of the Hilbert uniqueness method devoted to the calculation of the control in two different cases:zone control and pointwise control. 展开更多
关键词 Parameter dependent system averaged regional controllability averaged control Hilbert uniqueness method minimum energy
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DISCUSSION ON AVERAGE GENERATION OF TWODIMENSIONAL DATA SEQUENCE IN GREY SYSTEM THEORY
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作者 PINGXue-liang ZHOURu-rong LIUSheng-lan 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第4期298-303,共6页
An unequal time interval sequence or a sequence with blanks is usually completed with average generation in grey system theory. This paper discovers that there exists obvious errors when using average generation to ge... An unequal time interval sequence or a sequence with blanks is usually completed with average generation in grey system theory. This paper discovers that there exists obvious errors when using average generation to generate internal points of non-consecutive neighbours. The average generation and the preference generation of the sequence are discussed, the concave and convex properties show the status of local sequence and propose a new idea for using the status to build up the criteria of choosing generation coefficient. Compared with the general average method of the one-dimensional data sequence, the two-dimensional data sequence is defined and its average generation is discussed, and the coefficient decision method for the preference generation is presented. 展开更多
关键词 average generation grey system theory data sequence non-consecutive neighbors
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Average Convergence for Directed&Undirected Graphs in Distributed Systems
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作者 Ali Mustafa M Najam ul Islam Salman Ahmed 《Computer Systems Science & Engineering》 SCIE EI 2021年第6期399-413,共15页
Consensus control of multi-agent systems is an innovative paradigm for the development of intelligent distributed systems.This has fascinated numerous scientific groups for their promising applications as they have th... Consensus control of multi-agent systems is an innovative paradigm for the development of intelligent distributed systems.This has fascinated numerous scientific groups for their promising applications as they have the freedom to achieve their local and global goals and make their own decisions.Network communication topologies based on graph and matrix theory are widely used in a various real-time applications ranging from software agents to robotics.Therefore,while sustaining the significance of both directed and undirected graphs,this research emphases on the demonstration of a distributed average consensus algorithm.It uses the harmonic mean in the domain of multi-agent systems with directed and undirected graphs under static topologies based on a control input scheme.The proposed agreement protocol focuses on achieving a constant consensus on directional and undirected graphs using the exchange of information between neighbors to update their status values and to be able to calculate the total number of agents that contribute to the communication network at the same time.The proposed method is implemented for the identical networks that are considered under the directional and non-directional communication links.Two different scenarios are simulated and it is concluded that the undirected approach has an advantage over directed graph communication in terms of processing time and the total number of iterations required to achieve convergence.The same network parameters are introduced for both orientations of the communication graphs.In addition,the results of the simulation and the calculation of various matrices are provided at the end to validate the effectiveness of the proposed algorithm to achieve consensus. 展开更多
关键词 Multi-agent systems average consensus distributed estimation directed graphs undirected graphs agent counting
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Sufficient Condition for Average Consensus of Directed Networked Multi-agent Systems with Time Delays
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作者 王朝霞 杜大军 费敏锐 《Journal of Donghua University(English Edition)》 EI CAS 2014年第2期119-123,共5页
The average consensus problem in a directed network of multi-agent systems with communication time delays was investigated. The directed networks were balanced and weakly connected with fixed or switching topology dig... The average consensus problem in a directed network of multi-agent systems with communication time delays was investigated. The directed networks were balanced and weakly connected with fixed or switching topology digraph. Based on frequency domain analysis method, a sufficient condition of asymptotic stability of multi-agent systems with time delays was obtained,where the analytic formula between the maximum time delay and the directed network structure was provided. The maximum time delay can be derived directly and easily by the eigenvalue of Laplacian L. Numerical examples confirm the effectiveness of the proposed technique. 展开更多
关键词 average consensus MULTI-AGENT time delay frequency domain analysis
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Application of Weighted Average Method in Evaluation System for Rural Cadre Distance Education
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作者 DAI Li-na1,ZHENG Bo-wei1,DONG Hai-ge2 1.Institute of Agricultural Scientech Information,Beijing Academy of Agriculture and Forestry Sciences,Beijing 100097,China 2.Food Quality Supervision and Management Section,Chaoyang Branch of Beijing Administration for Industry and Commerce,Beijing 100125,China 《Asian Agricultural Research》 2012年第3期66-68,共3页
We elaborate the application method,process and effect of weighted average method in the examination and evaluation system for modern distance education of rural party members and cadres.The study shows that this meth... We elaborate the application method,process and effect of weighted average method in the examination and evaluation system for modern distance education of rural party members and cadres.The study shows that this method reflects the evaluation results objectively and comprehensively and plays a remarkable role in establishing and improving the examination and evaluation system,thus will have an important reference value for the development of modern distance education of rural party members and cadres in the future. 展开更多
关键词 RURAL modern DISTANCE education WEIGHTED average m
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A correlation OPTS algorithm for reducing peak to average power ratio of FBMC-OQAM systems
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作者 WANG Xing MA Tianming +1 位作者 LI Fengrong ZHAO Qinghua 《High Technology Letters》 EI CAS 2022年第2期208-216,共9页
A correlation overlapping partial transmit sequence(C-OPTS) algorithm is proposed to solve the issue of high complexity of overlapping partial transmit sequence(OPTS) algorithm in suppressing the peak to average power... A correlation overlapping partial transmit sequence(C-OPTS) algorithm is proposed to solve the issue of high complexity of overlapping partial transmit sequence(OPTS) algorithm in suppressing the peak to average power ratio(PAPR) of filter bank multicarrier-offset quadrature amplitude modulation(FBMC-OQAM) signals.The V subblocks in partial transmit sequence(PTS) are regrouped into U combinations according to the correlation coefficient p,and overlapping subblocks are allowed between adjacent groups.The search starts from the first group and sets the phase factors of the subsequent groups to 1.When the phase factors of the non-overlapping subblocks in the first group are determined,the subsequent groups are searched in turn to determine their respective phase factors.Starting from the second data block,the data overlapped with it should be taken into account when determining its optimal phase factor vector.Theoretical analysis and simulation results indicate that compared with the OPTS algorithm,the proposed algorithm can significantly reduce the computational complexity at the cost of slight deterioration of PAPR performance.Meanwhile,compared with the even-odd iterative double-layers OPTS(ID-OPTS) algorithm,it can further reduce the complexity and obtain a better PAPR suppression effect. 展开更多
关键词 filter bank multicarrier(FBMC) offset quadrature amplitude modulation(OQAM) peak to average power ratio(PAPR) overlapping partial transmit sequence(OPTS) correlation coefficient
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Average Angular Momentum for the ^(12)C+^(93)Nb System at Near-and Sub-Barrier Energies
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作者 Qian Xing Jiang Dong-xing Lin Jun-song(Department of Technical Physics,Peking University,Beijing 100871)Liu Da-ming Li Ze(China Institute of Atomic Energy,P.O.Box 275(48),Beijing 102413) 《Chinese journal of nuclear physics》 1995年第2期118-123,共6页
Partial cross sections of two-and three-neutron evaporation channels follow-ing the fusion reaction <sup>12</sup>C+<sup>93</sup>Nb are measured for center-of-mass energies from 25.0MeV to 40.5 ... Partial cross sections of two-and three-neutron evaporation channels follow-ing the fusion reaction <sup>12</sup>C+<sup>93</sup>Nb are measured for center-of-mass energies from 25.0MeV to 40.5 MeV.The total fusion cross sections and average angular momemta havebeen deduced from these cross sections on the basis of statistical evaporation model cal-culation.The fusion cross sections are well reproduced by the simplified coupled chan-nel model.The average angular momenta deduced from the partial cross section ratiosare consistent with those extracted from the coupled channel calculation. 展开更多
关键词 Partial CROSS SECTION Fusion CROSS SECTION average angular momentum
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The Average Power of a System under Random Excitation
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作者 SUN Yong1 J. MATHEW2 +3 位作者 ZHANG Min-hui3 ZHANG Zhi-hun1(1. Industrial Design Department, Nanchang University, Nanchang, 330029, P.R. China 2. Department of Mechanical Engineering, Monash University, Caulfield East Melbourne, Australia 3 Image Department, Jiangxi Medical University, Nanchang, 330006, P.R. China) 《International Journal of Plant Engineering and Management》 1999年第Z1期497-505,共9页
The Taylor series expansion method is used to derive an approximation for theaverage total power of a non-linear system subjected to wide-band random excitation with zeromean value. The average dissipating power for n... The Taylor series expansion method is used to derive an approximation for theaverage total power of a non-linear system subjected to wide-band random excitation with zeromean value. The average dissipating power for non-linear systems subjected to randomexcitation is also discussed. The results of the derivation show that the average total power andthe average dissipating Power of a Systems are independent, of the dissipating force of the systemwhen excited by white noise. On the other hand, the average total energy is show,l to be inverselyproportional to damping,. The total power is dependent on both, the input and dissipating powerof the system. 展开更多
关键词 average Power Non-linear systems Random vibration
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Mass spectrometry for non-destructive detection of the average diameter of micro copper wires
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作者 Rui Su Xiaowei Fang +5 位作者 Peng Zeng Yong Qian Xuanzhu Li Huiyu Xing Jiamei Lin Jiaquan Xu 《Chinese Chemical Letters》 2025年第10期474-477,共4页
The performance and price of copper-based micro linear products are determined by the diameter uniformity.How to accurately detect the wire diameter of long-length copper based micro linear products without cutting or... The performance and price of copper-based micro linear products are determined by the diameter uniformity.How to accurately detect the wire diameter of long-length copper based micro linear products without cutting or damage has always been a technical concern for production enterprises.Herein,a novel approach was developed for nondestructive detection of the average diameter at any given segment of a long copper wire by assessing the adsorption capacity of arginine on its surface.The amount of adsorbent on the surface of the copper wire exhibits a positive correlation with the area,which can be detected by extractive electrospray ionization mass spectrometry(EESI-MS)after online elution with ammonia.The experimental results demonstrated that the analysis can be completed within 15 min,with a good linear relationship between copper wires with different diameters and the adsorption capacity of arginine.The linear correlation coefficient R2was 0.995,the relative standard deviation was 1.10%-2.81%,and the detection limit reached 2.5μm(length of segment=4 cm),showing potential applications for facile measurement of the average diameter of various metal wires. 展开更多
关键词 Measurement of diameter Mass spectrometry Non-destructive detection Copper wire average diameter Measurement of diameter Mass spectrometry Non-destructive detection Copper wire average diameter
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