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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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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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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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Preweaning period is a critical window for rumen microbial regulation of average daily gain in Holstein heifer calves 被引量:2
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作者 Shengyang Xu Chong Jiao +1 位作者 Qiyu Diao Yan Tu 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期396-411,共16页
Background Rumen bacterial groups can affect growth performance,such as average daily gain(ADG),feed intake,and efficiency.The study aimed to investigate the inter-relationship of rumen bacterial composition,rumen fer... Background Rumen bacterial groups can affect growth performance,such as average daily gain(ADG),feed intake,and efficiency.The study aimed to investigate the inter-relationship of rumen bacterial composition,rumen fermentation indicators,serum indicators,and growth performance of Holstein heifer calves with different ADG.Twelve calves were chosen from a trail with 60 calves and divided into higher ADG(HADG,high pre-and post-weaning ADG,n=6)and lower ADG(LADG,low pre-and post-weaning ADG,n=6)groups to investigate differences in bacterial composition and functions and host phenotype.Results During the preweaning period,the relative abundances of propionate producers,including g_norank_f_Butyricicoccaceae,g_Pyramidobacter,and g_norank_f_norank_o_Clostridia_vadin BB60_group,were higher in HADG calves(LDA>2,P<0.05).Enrichment of these bacteria resulted in increased levels of propionate,a gluconeogenic precursor,in preweaning HADG calves(adjusted P<0.05),which consequently raised serum glucose concentrations(adjusted P<0.05).In contrast,the relative abundances of rumen bacteria in post-weaning HADG calves did not exert this effect.Moreover,no significant differences were observed in rumen fermentation parameters and serum indices between the two groups.Conclusions The findings of this study revealed that the preweaning period is the window of opportunity for rumen bacteria to regulate the ADG of calves. 展开更多
关键词 average daily gain CALVES Preweaning period Rumen microbiota
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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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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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A Low Complexity Linear Moving Average Filtering Technique for PAR Reduction in OFDM Systems
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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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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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Improved Double Deep Q Network Algorithm Based on Average Q-Value Estimation and Reward Redistribution for Robot Path Planning
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作者 Yameng Yin Lieping Zhang +3 位作者 Xiaoxu Shi Yilin Wang Jiansheng Peng Jianchu Zou 《Computers, Materials & Continua》 SCIE EI 2024年第11期2769-2790,共22页
By integrating deep neural networks with reinforcement learning,the Double Deep Q Network(DDQN)algorithm overcomes the limitations of Q-learning in handling continuous spaces and is widely applied in the path planning... By integrating deep neural networks with reinforcement learning,the Double Deep Q Network(DDQN)algorithm overcomes the limitations of Q-learning in handling continuous spaces and is widely applied in the path planning of mobile robots.However,the traditional DDQN algorithm suffers from sparse rewards and inefficient utilization of high-quality data.Targeting those problems,an improved DDQN algorithm based on average Q-value estimation and reward redistribution was proposed.First,to enhance the precision of the target Q-value,the average of multiple previously learned Q-values from the target Q network is used to replace the single Q-value from the current target Q network.Next,a reward redistribution mechanism is designed to overcome the sparse reward problem by adjusting the final reward of each action using the round reward from trajectory information.Additionally,a reward-prioritized experience selection method is introduced,which ranks experience samples according to reward values to ensure frequent utilization of high-quality data.Finally,simulation experiments are conducted to verify the effectiveness of the proposed algorithm in fixed-position scenario and random environments.The experimental results show that compared to the traditional DDQN algorithm,the proposed algorithm achieves shorter average running time,higher average return and fewer average steps.The performance of the proposed algorithm is improved by 11.43%in the fixed scenario and 8.33%in random environments.It not only plans economic and safe paths but also significantly improves efficiency and generalization in path planning,making it suitable for widespread application in autonomous navigation and industrial automation. 展开更多
关键词 Double Deep Q Network path planning average Q-value estimation reward redistribution mechanism reward-prioritized experience selection method
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Optimizing Average Electric Power During the Charging of Lithium-Ion Batteries Through the Taguchi Method
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作者 Mohd H.S.Alrashdan 《Transactions of Tianjin University》 EI CAS 2024年第2期152-166,共15页
In recent times, lithium-ion batteries have been widely used owing to their high energy density, extended cycle lifespan, and minimal self-discharge rate. The design of high-speed rechargeable lithium-ion batteries fa... In recent times, lithium-ion batteries have been widely used owing to their high energy density, extended cycle lifespan, and minimal self-discharge rate. The design of high-speed rechargeable lithium-ion batteries faces a significant challenge owing to the need to increase average electric power during charging. This challenge results from the direct influence of the power level on the rate of chemical reactions occurring in the battery electrodes. In this study, the Taguchi optimization method was used to enhance the average electric power during the charging process of lithium-ion batteries. The Taguchi technique is a statistical strategy that facilitates the systematic and efficient evaluation of numerous experimental variables. The proposed method involved varying seven input factors, including positive electrode thickness, positive electrode material, positive electrode active material volume fraction, negative electrode active material volume fraction, separator thickness, positive current collector thickness, and negative current collector thickness. Three levels were assigned to each control factor to identify the optimal conditions and maximize the average electric power during charging. Moreover, a variance assessment analysis was conducted to validate the results obtained from the Taguchi analysis. The results revealed that the Taguchi method was an eff ective approach for optimizing the average electric power during the charging of lithium-ion batteries. This indicates that the positive electrode material, followed by the separator thickness and the negative electrode active material volume fraction, was key factors significantly infl uencing the average electric power during the charging of lithium-ion batteries response. The identification of optimal conditions resulted in the improved performance of lithium-ion batteries, extending their potential in various applications. Particularly, lithium-ion batteries with average electric power of 16 W and 17 W during charging were designed and simulated in the range of 0-12000 s using COMSOL Multiphysics software. This study efficiently employs the Taguchi optimization technique to develop lithium-ion batteries capable of storing a predetermined average electric power during the charging phase. Therefore, this method enables the battery to achieve complete charging within a specific timeframe tailored to a specificapplication. The implementation of this method can save costs, time, and materials compared with other alternative methods, such as the trial-and-error approach. 展开更多
关键词 Lithium-ion batteries average electric power during charging Taguchi method COMSOL Multiphysics software C rate L27 orthogonal array
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Libration-Generated Average Convection in a Rotating Flat Layer with Horizontal Axis
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作者 Kirill Rysin 《Fluid Dynamics & Materials Processing》 EI 2024年第10期2235-2249,共15页
The study of average convection in a rotating cavity subjected to modulated rotation is an interesting area for the development of both fundamental and applied science.This phenomenon finds application in the field of... The study of average convection in a rotating cavity subjected to modulated rotation is an interesting area for the development of both fundamental and applied science.This phenomenon finds application in the field of mass transfer and fluid flow control,relevant examples being crystal growth under reduced gravity and fluid mixing in microfluidic devices for cell cultures.In this study,the averaged flow generated by the oscillating motion of a fluid in a planar layer rotating about a horizontal axis is experimentally investigated.The boundaries of the layer are maintained at constant temperatures,while the lateral cylindrical wall is thermally insulated.It is demonstrated that libration results in intense oscillatory fluid motion,which in turn produces a time-averaged flow.For the first time,quantitative measures for the instantaneous velocity field are obtained using the Particle Image Velocimetry technique.It is revealed that the flow has the form of counter-rotating vortices.The vortex circulations sense changes during a libration cycle.An increase in the rotation rate and amplitude of the cavity libration results in an increase in the flow intensity.The heat transfer and time-averaged velocity are examined accordingly as a function of the dimensionless oscillation frequency,and resonant excitation of heat transfer and average oscillation velocity are revealed.The threshold curve for the onset of the averaged convection is identified in the plane of control parameters(dimensionless rotational velocity and pulsation Reynolds number).It is found that an increase in the dimensionless rotational velocity has a stabilizing effect on the onset of convection. 展开更多
关键词 ROTATION LIBRATION OSCILLATIONS mass transfer stability averaged convection
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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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Average Secrecy Capacity of the Reconfigurable Intelligent Surface-Assisted Integrated Satellite Unmanned Aerial Vehicle Relay Networks
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作者 Ping Li Kefeng Guo +2 位作者 Feng Zhou XuelingWang Yuzhen Huang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1849-1864,共16页
Integrated satellite unmanned aerial vehicle relay networks(ISUAVRNs)have become a prominent topic in recent years.This paper investigates the average secrecy capacity(ASC)for reconfigurable intelligent surface(RIS)-e... Integrated satellite unmanned aerial vehicle relay networks(ISUAVRNs)have become a prominent topic in recent years.This paper investigates the average secrecy capacity(ASC)for reconfigurable intelligent surface(RIS)-enabled ISUAVRNs.Especially,an eve is considered to intercept the legitimate information from the considered secrecy system.Besides,we get detailed expressions for the ASC of the regarded secrecy system with the aid of the reconfigurable intelligent.Furthermore,to gain insightful results of the major parameters on the ASC in high signalto-noise ratio regime,the approximate investigations are further gotten,which give an efficient method to value the secrecy analysis.At last,some representative computer results are obtained to prove the theoretical findings. 展开更多
关键词 Integrated satellite unmanned aerial vehicle relay networks reconfigurable intelligent surface average secrecy capacity(ASC) asymptotic ASC
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Reliability-BasedModel for Incomplete Preventive ReplacementMaintenance of Photovoltaic Power Systems
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作者 Wei Chen Ming Li +2 位作者 Tingting Pei Cunyu Sun Huan Lei 《Energy Engineering》 EI 2024年第1期125-144,共20页
At present,the operation and maintenance of photovoltaic power generation systems mainly comprise regular maintenance,breakdown maintenance,and condition-based maintenance,which is very likely to lead to over-or under... At present,the operation and maintenance of photovoltaic power generation systems mainly comprise regular maintenance,breakdown maintenance,and condition-based maintenance,which is very likely to lead to over-or under-repair of equipment.Therefore,a preventive maintenance and replacement strategy for PV power generation systems based on reliability as a constraint is proposed.First,a hybrid failure function with a decreasing service age factor and an increasing failure rate factor is introduced to describe the deterioration of PV power generation equipment,and the equipment is replaced when its reliability drops to the replacement threshold in the last cycle.Then,based on the reliability as a constraint,the average maintenance cost and availability of the equipment are considered,and the non-periodic incomplete maintenance model of the PV power generation system is established to obtain the optimal number of repairs,each maintenance cycle and the replacement cycle of the PV power generation system components.Next,the inverter of a PV power plant is used as a research object.The model in this paper is compared and analyzed with the equal cycle maintenance model without considering reliability and the maintenance model without considering the equipment replacement threshold,Through model comparison,when the optimal maintenance strategy is(0.80,4),the average maintenance cost of this paper’s model are decreased by 20.3%and 5.54%and the availability is increased by 0.2395% and 0.0337%,respectively,compared with the equal-cycle maintenance model without considering the reliability constraint and the maintenance model without considering the equipment replacement threshold.Therefore,this maintenance model can ensure the high reliability of PV plant operation while increasing the equipment availability to improve the system economy. 展开更多
关键词 RELIABILITY photovoltaic power system average maintenance cost AVAILABILITY incomplete preventive maintenance hybrid failure rate
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Cost analysis of radical resection of malignant breast tumors under the China Healthcare Security Diagnosis Related Groups payment system
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作者 Yun-He Hu Ai-Dong Li 《World Journal of Clinical Cases》 SCIE 2024年第20期4174-4179,共6页
BACKGROUND Breast cancer is one of the most common malignant tumors in women worldwide and poses a severe threat to their health.Therefore,this study examined patients who underwent breast cancer surgery,analyzed hosp... BACKGROUND Breast cancer is one of the most common malignant tumors in women worldwide and poses a severe threat to their health.Therefore,this study examined patients who underwent breast cancer surgery,analyzed hospitalization costs and structure,and explored the impact of China Healthcare Security Diagnosis Related Groups(CHS-DRG)management on patient costs.It aimed to provide medical institutions with ways to reduce costs,optimize cost structures,reduce patient burden,and improve service efficiency.AIM To study the CHS-DRG payment system’s impact on breast cancer surgery costs.METHODS Using the CHS-DRG(version 1.1)grouping criteria,4073 patients,who underwent the radical resection of breast malignant tumors from January to December 2023,were included in the JA29 group;1028 patients were part of the CHS-DRG payment system,unlike the rest.Through an independent sample t-test,the length of hospital stay as well as total hospitalization,medicine and consumables,medical,nursing,medical technology,and management expenses were compared.Pearson’s correlation coefficient was used to test the cost correlation.RESULTS In terms of hospitalization expenses,patients in the CHS-DRG payment group had lower medical,nursing,and management expenses than those in the diagnosis-related group(DRG)non-payment group.For patients in the DRG payment group,the factors affecting the total hospitalization cost,in descending order of relevance,were medicine and consumable costs,consumable costs,medicine costs,medical costs,medical technology costs,management costs,nursing costs,and length of hospital stay.For patients in the DRG nonpayment group,the factors affecting the total hospitalization expenses in descending order of relevance were medicines and consumable expenses,consumable expenses,medical technology expenses,the cost of medicines,medical expenses,nursing expenses,length of hospital stay,and management expenses.CONCLUSION The CHS-DRG system can help control and reduce unnecessary medical expenses by controlling medicine costs,medical consumable costs,and the length of hospital stay while ensuring medical safety. 展开更多
关键词 China Healthcare Security Diagnosis Related Groups Real-world study Radical resection of malignant breast tumors Hospitalization costs Cost structure average length of stay
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