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Analysis of Strength Training in the Training of Shot-Putters
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作者 Heng Wang 《Journal of Contemporary Educational Research》 2024年第6期89-95,共7页
The shot put is a sport that requires very high explosive power and precise technique.Strength training occupies the core position in the training of shot-putters,which can not only improve the throwing distance of at... The shot put is a sport that requires very high explosive power and precise technique.Strength training occupies the core position in the training of shot-putters,which can not only improve the throwing distance of athletes but also enhance their competitive state and prevent sports injuries.The purpose of this paper is to analyze the principles,classification,methods,and specific exercises of strength training in the training of shot-putters,in order to provide scientific training guidance for shot-putters. 展开更多
关键词 Shot-put movement Strength training Explosive power Maximum power Functional training
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Risk-Balanced Routing Strategy for Service Function Chains of Cyber-Physical Power System Considering Cross-Space Cascading Failure
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作者 He Wang Xingyu Tong +2 位作者 Huanan Yu XiaoHu Jing Bian 《Energy Engineering》 EI 2024年第9期2525-2542,共18页
Cyber-physical power system(CPPS)has significantly improved the operational efficiency of power systems.However,cross-space cascading failures may occur due to the coupling characteristics,which poses a great threat t... Cyber-physical power system(CPPS)has significantly improved the operational efficiency of power systems.However,cross-space cascading failures may occur due to the coupling characteristics,which poses a great threat to the safety and reliability of CPPS,and there is an acute need to reduce the probability of these failures.Towards this end,this paper first proposes a cascading failure index to identify and quantify the importance of different information in the same class of communication services.On this basis,a joint improved risk-balanced service function chain routing strategy(SFC-RS)is proposed,which is modeled as a robust optimization problem and solved by column-and-constraint generation(C-CG)algorithm.Compared with the traditional shortest-path routing algorithm,the superiority of SFC-RS is verified in the IEEE 30-bus system.The results demonstrate that SFC-RS effectively mitigates the risk associated with information transmission in the network,enhances information transmission accessibility,and effectively limits communication disruption from becoming the cause of cross-space cascading failures. 展开更多
关键词 Cyber-physical power system service function chain risk balance routing optimization cascading failure
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Evaluation of Generalized Error Function via Fast-Converging Power Series
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作者 Serdar Beji 《Advances in Pure Mathematics》 2024年第6期495-514,共20页
A generalized form of the error function, Gp(x)=pΓ(1/p)∫0xe−tpdt, which is directly associated with the gamma function, is evaluated for arbitrary real values of p>1and 0x≤+∞by employing a fast-converging power... A generalized form of the error function, Gp(x)=pΓ(1/p)∫0xe−tpdt, which is directly associated with the gamma function, is evaluated for arbitrary real values of p>1and 0x≤+∞by employing a fast-converging power series expansion developed in resolving the so-called Grandi’s paradox. Comparisons with accurate tabulated values for well-known cases such as the error function are presented using the expansions truncated at various orders. 展开更多
关键词 Generalized Error Function Gamma Function Grandi’s Paradox Fast-Converging power Series
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Detecting Icing on the Blades of a Wind Turbine Using a Deep Neural Network
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作者 Tingshun Li Jiaohui Xu +2 位作者 Zesan Liu Dadi Wang Wen Tan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第2期767-782,共16页
The blades of wind turbines located at high latitudes are often covered with ice in late autumn and winter,where this affects their capacity for power generation as well as their safety.Accurately identifying the icin... The blades of wind turbines located at high latitudes are often covered with ice in late autumn and winter,where this affects their capacity for power generation as well as their safety.Accurately identifying the icing of the blades of wind turbines in remote areas is thus important,and a general model is needed to this end.This paper proposes a universal model based on a Deep Neural Network(DNN)that uses data from the Supervisory Control and Data Acquisition(SCADA)system.Two datasets from SCADA are first preprocessed through undersampling,that is,they are labeled,normalized,and balanced.The features of icing of the blades of a turbine identified in previous studies are then used to extract training data from the training dataset.A middle feature is proposed to show how a given feature is correlated with icing on the blade.Performance indicators for the model,including a reward function,are also designed to assess its predictive accuracy.Finally,the most suitable model is used to predict the testing data,and values of the reward function and the predictive accuracy of the model are calculated.The proposed method can be used to relate continuously transferred features with a binary status of icing of the blades of the turbine by using variables of the middle feature.The results here show that an integrated indicator systemis superior to a single indicator of accuracy when evaluating the prediction model. 展开更多
关键词 DNN predicting blade icing SCADA data wind power reward function
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Breakdown Voltage Prediction by Utilizing the Behavior of Natural Ester for Transformer Applications
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作者 P.Samuel Pakianathan R.V.Maheswari 《Intelligent Automation & Soft Computing》 SCIE 2023年第3期2717-2736,共20页
This research investigates the dielectric performance of Natural Ester(NE)using the Partial Differential Equation(PDE)tool and analyzes dielectric performance using fuzzy logic.NE nowadays is found to replace Mineral ... This research investigates the dielectric performance of Natural Ester(NE)using the Partial Differential Equation(PDE)tool and analyzes dielectric performance using fuzzy logic.NE nowadays is found to replace Mineral Oil(MO)due to its extensive dielectric properties.Here,the heat-tolerant Natural Esters Olive oil(NE1),Sunflower oil(NE2),and Ricebran oil(NE3)are subjected to High Voltage AC(HVAC)under different electrodes configurations.The break-down voltage and leakage current of NE1,NE2,and NE3 under Point-Point(P-P),Sphere-Sphere(S-S),Plane-Plane(PL-PL),and Rod-Rod(R-R)are measured,and survival probability is presented.The electricfield distribution is analyzed using the Partial Differential Equation(PDE)tool.NE shows better HVAC with stand capacity under all the electrodes configuration,especially in the S-S shape geometry.The exponential function is developed for the oils under different elec-trode geometry;NE shows a higher survival probability.Likewise,the most influ-ential dielectric properties such as breakdown voltage,kinematic viscosity,and water content are used to develop a Mamdani-based control system model that combines two variables to produce the surface model.The surface model indi-cates that the NE subjected for investigation is less susceptible to moisture effect and higher kinematic viscosity.Based on the surface models of PDE and fuzzy,it is concluded that NE possesses a high survival rate since its breakdown voltage does not react to changes in water content.Hence the application of NE in the transformer application is highly safe and possesses extended life. 展开更多
关键词 power transformer fuzzy logic prediction partial differential equation natural ester exponential function
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VECTOR-VALUED RANDOM POWER SERIES ON THE UNIT BALL OF C~n 被引量:2
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作者 李英奎 刘培德 《Acta Mathematica Scientia》 SCIE CSCD 2007年第1期57-66,共10页
In this article, the authors study the vector-valued random power series on the unit ball of C^n and get vector-valued Salem-Zygmund theorem for them by using martingale technique. Further, the relationships between v... In this article, the authors study the vector-valued random power series on the unit ball of C^n and get vector-valued Salem-Zygmund theorem for them by using martingale technique. Further, the relationships between vector-valued random power series and several function spaces are also studied. 展开更多
关键词 Random power series Rademacher function Salem-Zygmund theorem
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RECURSIVE REPRODUCING KERNELS HILBERT SPACES USING THE THEORY OF POWER KERNELS 被引量:1
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作者 M. Mouattamid 《Analysis in Theory and Applications》 2012年第2期111-124,共14页
The main objective of this work is to decompose orthogonally the reproducing kernels Hilbert space using any conditionally positive definite kernels into smaller ones by introducing the theory of power kernels, and to... The main objective of this work is to decompose orthogonally the reproducing kernels Hilbert space using any conditionally positive definite kernels into smaller ones by introducing the theory of power kernels, and to show how to do this decomposition recur- sively. It may be used to split large interpolation problems into smaller ones with different kernels which are related to the original kernels. To reach this objective, we will reconstruct the reproducing kernels Hilbert space for the normalized and the extended kernels and give the recursive algorithm of this decomposition. 展开更多
关键词 Hilber space reproducing kernel interpolant power function and Condition-ally positive kernel
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The invariant of the stiffness filter function with the weight filter function of the power function form
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作者 Zhen Shang Yun-Kang Sui 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第6期1617-1619,共3页
Based on the independent, continuous and map- ping (ICM) method and homogenization method, a research model is constructed to propose and deduce a theorem and corollary from the invariant between the weight filter f... Based on the independent, continuous and map- ping (ICM) method and homogenization method, a research model is constructed to propose and deduce a theorem and corollary from the invariant between the weight filter func- tion and the corresponding stiffness filter function of the form of power function. The efficiency in searching for op- timum solution will be raised via the choice of rational filter functions, so the above mentioned results are very important to the further study of structural topology optimization. 展开更多
关键词 ICM method Filter function power function INVARIANT
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Investigations into Some Simple Expressions of the Gamma Function in Wind Power Theoretical Estimate by the Weibull Distribution
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作者 Siaka Touré 《Journal of Applied Mathematics and Physics》 2019年第12期2990-3002,共13页
The Weibull distribution is a probability density function (PDF) which is widely used in the study of meteorological data. The statistical analysis of the wind speed v by using the Weibull distribution leads to the es... The Weibull distribution is a probability density function (PDF) which is widely used in the study of meteorological data. The statistical analysis of the wind speed v by using the Weibull distribution leads to the estimate of the mean wind speed , the variance of v around and the mean power density in the wind. The gamma function Γ is involved in those calculations, particularly Γ (1+1/k), Γ (1+2/k) and Γ (1+3/k). The paper reports the use of the Weibull PDF f(v) to estimate the gamma function. The study was performed by looking for the wind speeds related to the maximum values of f(v), v2 f(v) and v3 f(v). As a result, some approximate relationships were obtained for Γ (1+1/k), Γ (1+2/k) and Γ (1+3/k), that use some fitting polynomial functions. Very good agreements were found between the exact and the estimated values of Γ (1+n/k) that can be used for the estimation of the mean wind speed , the variance σ2 of the wind speed v;around the mean speed and the average wind power density. 展开更多
关键词 GAMMA FUNCTION Weibull Distribution Beta FUNCTION Mean WIND Speed AVERAGE WIND power Density
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Control Charts for the Shape Parameter of Power Function Distribution under Different Classical Estimators
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作者 Azam Zaka Ahmad Saeed Akhter +1 位作者 Riffat Jabeen Aamir Sanaullah 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第6期1201-1223,共23页
In practice,the control charts for monitoring of process mean are based on the normality assumption.But the performance of the control charts is seriously affected if the process of quality characteristics departs fro... In practice,the control charts for monitoring of process mean are based on the normality assumption.But the performance of the control charts is seriously affected if the process of quality characteristics departs from normality.For such situations,we have modified the already existing control charts such as Shewhart control chart,exponentially weighted moving average(EWMA)control chart and hybrid exponentially weighted moving average(HEWMA)control chart by assuming that the distribution of underlying process follows Power function distribution(PFD).By considering the situation that the parameters of PFD are unknown,we estimate them by using three classical estimation methods,i.e.,percentile estimator(P.E),maximum likelihood estimator(MLE)and modified maximum likelihood estimator(MMLE).We construct Shewhart,EWMA and HEWMA control charts based on P.E,MLE and MMLE.We have compared all these control charts using Monte Carlo simulation studies and concluded that HEWMA control chart under MLE is more sensitive to detect an early shift in the shape parameter when the distribution of the underlying process follows power function distribution. 展开更多
关键词 Average run length control chart percentile estimator power function distribution
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Computational Precision of the Power Function for Conditional Tests of Assumptions of the Rasch Model
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作者 Clemens Draxler Jan Philipp Nolte 《Open Journal of Statistics》 2018年第6期873-884,共12页
Draxler and Zessin [1] derived the power function for a class of conditional tests of assumptions of a psychometric model known as the Rasch model and suggested an MCMC approach developed by Verhelst [2] for the numer... Draxler and Zessin [1] derived the power function for a class of conditional tests of assumptions of a psychometric model known as the Rasch model and suggested an MCMC approach developed by Verhelst [2] for the numerical approximation of the power of the tests. In this contribution, the precision of the Verhelst approach is investigated and compared with an exact sampling procedure proposed by Miller and Harrison [3] for which the discrete probability distribution to be sampled from is exactly known. Results show no substantial differences between the two numerical procedures and quite accurate power computations. Regarding the question of computing time the Verhelst approach will have to be considered much more efficient. 展开更多
关键词 CONDITIONAL Tests CONDITIONAL PROBABILITY DISTRIBUTION HYPERGEOMETRIC DISTRIBUTION power Function RANDOM Sampling RASCH Model
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On the Power Performance of Test Statistics for the Generalized Rayleigh Interval Grouped Data
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作者 Hatim Solayman Migdadi 《Open Journal of Statistics》 2015年第5期474-482,共9页
In this paper, the weighted Kolmogrov-Smirnov, Cramer von-Miss and the Anderson Darling test statistics are considered as goodness of fit tests for the generalized Rayleigh interval grouped data. An extensive simulati... In this paper, the weighted Kolmogrov-Smirnov, Cramer von-Miss and the Anderson Darling test statistics are considered as goodness of fit tests for the generalized Rayleigh interval grouped data. An extensive simulation process is conducted to evaluate their controlling of type 1 error and their power functions. Generally, the weighted Kolmogrov-Smirnov test statistics show a relatively better performance than both, the Cramer von-Miss and the Anderson Darling test statistics. For large sample values, the Anderson Darling test statistics cannot control type 1 error but for relatively small sample values it indicates a better performance than the Cramer von-Miss test statistics. Best selection of the test statistics and highlights for future studies are also explored. 展开更多
关键词 GENERALIZED RAYLEIGH Distribution INTERVAL Grouped Data GOODNESS of FIT Tests Empirical Type 1 ERROR power Function
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The Effectiveness of the Squared Error and Higgins-Tsokos Loss Functions on the Bayesian Reliability Analysis of Software Failure Times under the Power Law Process
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作者 Freeh N. Alenezi Christ P. Tsokos 《Engineering(科研)》 2019年第5期272-299,共28页
Reliability analysis is the key to evaluate software’s quality. Since the early 1970s, the Power Law Process, among others, has been used to assess the rate of change of software reliability as time-varying function ... Reliability analysis is the key to evaluate software’s quality. Since the early 1970s, the Power Law Process, among others, has been used to assess the rate of change of software reliability as time-varying function by using its intensity function. The Bayesian analysis applicability to the Power Law Process is justified using real software failure times. The choice of a loss function is an important entity of the Bayesian settings. The analytical estimate of likelihood-based Bayesian reliability estimates of the Power Law Process under the squared error and Higgins-Tsokos loss functions were obtained for different prior knowledge of its key parameter. As a result of a simulation analysis and using real data, the Bayesian reliability estimate under the Higgins-Tsokos loss function not only is robust as the Bayesian reliability estimate under the squared error loss function but also performed better, where both are superior to the maximum likelihood reliability estimate. A sensitivity analysis resulted in the Bayesian estimate of the reliability function being sensitive to the prior, whether parametric or non-parametric, and to the loss function. An interactive user interface application was additionally developed using Wolfram language to compute and visualize the Bayesian and maximum likelihood estimates of the intensity and reliability functions of the Power Law Process for a given data. 展开更多
关键词 power LAW Process BAYESIAN Reliability Intensity FUNCTION KERNEL Density Loss FUNCTION Robustness
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The Equilibrium of Fractional Derivative and Second Derivative: The Mechanics of a Power-Law Visco-Elastic Solid
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作者 Franz Konstantin Fuss 《Applied Mathematics》 2016年第16期1903-1918,共17页
This paper investigates the equilibrium of fractional derivative and 2nd derivative, which occurs if the original function is damped (damping of a power-law viscoelastic solid with viscosities η of 0 ≤ η ≤ 1), whe... This paper investigates the equilibrium of fractional derivative and 2nd derivative, which occurs if the original function is damped (damping of a power-law viscoelastic solid with viscosities η of 0 ≤ η ≤ 1), where the fractional derivative corresponds to a force applied to the solid (e.g. an impact force), and the second derivative corresponds to acceleration of the solid’s centre of mass, and therefore to the inertial force. Consequently, the equilibrium satisfies the principle of the force equilibrium. Further-more, the paper provides a new definition of under- and overdamping that is not exclusively disjunctive, i.e. not either under- or over-damped as in a linear Voigt model, but rather exhibits damping phases co-existing consecutively as time progresses, separated not by critical damping, but rather by a transition phase. The three damping phases of a power-law viscoelastic solid—underdamping, transition and overdamping—are characterized by: underdamping—centre of mass oscillation about zero line;transition—centre of mass reciprocation without crossing the zero line;overdamping—power decay. The innovation of this new definition is critical for designing non-linear visco-elastic power-law dampers and fine-tuning the ratio of under- and overdamping, considering that three phases—underdamping, transition, and overdamping—co-exist consecutively if 0 < η < 0.401;two phases—transition and overdamping—co-exist consecutively if 0.401 < η < 0.578;and one phase— overdamping—exists exclusively if 0.578 < η < 1. 展开更多
关键词 Fractional Derivative Non-Linear Visco-Elasticity power Law Mittag-Leffler Function Underdamping Overdamping Innovative Design of Material Damping
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Lexico-grammatical Realization of Power in The Thorn Birds
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作者 LI Han-bing 《Journal of Literature and Art Studies》 2020年第3期199-202,共4页
This paper explores how the interpersonal meaning of power is realized by the lexico-grammatical patterns,taking one episode from the novel The Thorn Birds as examples.The analytical framework is drawn from systemic f... This paper explores how the interpersonal meaning of power is realized by the lexico-grammatical patterns,taking one episode from the novel The Thorn Birds as examples.The analytical framework is drawn from systemic functional grammar.The findings suggest that as a type of interpersonal meaning,power could be realized by non-reciprocal language patterns.The finding is meant to deepen our understanding of the relation between the meaning of text and the lexico-grammatical patterns that function to realize that meaning. 展开更多
关键词 power lexico-grammatical pattern SYSTEMIC FUNCTIONAL GRAMMAR
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Reciprocal Pattern of Power in The Thorn Birds
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作者 LI Han-bing WANG Ying 《Journal of Literature and Art Studies》 2020年第5期401-404,共4页
This paper explores how reciprocal pattern of power is realized in fictional texts.Taking a few episodes from the novel The Thorn Birds and the transitivity process as analytical framework,this paper holds that recipr... This paper explores how reciprocal pattern of power is realized in fictional texts.Taking a few episodes from the novel The Thorn Birds and the transitivity process as analytical framework,this paper holds that reciprocal patterns of power may be mutual-targeting or disjoint.A systematic network of both non-reciprocal and reciprocal pattern of power in fictional works is drawn on the basis of the analysis. 展开更多
关键词 power reciprocal pattern systemic functional grammar
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The Separation of Powers from Functions and the Establishment of a New Structure of Management and Operation of State-owned Assets
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作者 Zhou Li-qun Ph. D. of Economics. Associate Professor of Institute of Economics of NANKAI UNIVERSITY. Deputy Dean of College of Economics, NANKAI UNIVERSITY 《南开经济研究》 CSSCI 北大核心 1994年第S3期13-18,共6页
The development of the socialist market economy demands the furtherintensification of the reform of the management operating system (MOS)of the state-owned assets, the strengthening of the efficiency in the man-agemen... The development of the socialist market economy demands the furtherintensification of the reform of the management operating system (MOS)of the state-owned assets, the strengthening of the efficiency in the man-agement of state-owned assets,and the improvement of the operating bene- 展开更多
关键词 the Separation of powers from Functions and the Establishment of a New Structure of Management and Operation of State-owned Assets
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The Analytic Solution of Schrdinger Equation with Potential Function Superposed by Six Terms with Positive-power and Inverse-power Potentials
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作者 HU Xian-Quan LUO Guang +2 位作者 CUI Li-Peng LI Fang-Yu NIU Lian-Bin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第3期419-423,共5页
光线的 Schr&#246;dinger 方程的分析解决方案被在这篇文章使用几个积极力量、反力量的潜在的函数的紧张的联合条件学习。而且,当光线的 Schr&#246;dinger 方程的潜力是 V (r)=&#945; <SUB>1</SUB 时,精确,决... 光线的 Schr&#246;dinger 方程的分析解决方案被在这篇文章使用几个积极力量、反力量的潜在的函数的紧张的联合条件学习。而且,当光线的 Schr&#246;dinger 方程的潜力是 V (r)=&#945; <SUB>1</SUB 时,精确,决定分析答案的存在的分析答案和条件被寻找了> r <SUP>8</SUP>+&#945; <SUB>2</SUB > r <SUP>3</SUP>+&#945; <SUB>3</SUB > r <SUP>2</SUP>+&#946; <SUB>3</SUB > r <SUP>&#8722;1</SUP>+&#946; <SUB>2</SUB > r <SUP>&#8722;3</SUP>+&#946; <SUB>1</SUB > r <SUP>&#8722;4</SUP>。一般来说,仅仅有一个近似答案,然而并非有几个潜力的重叠的 Schr&#246;dinger 方程的分析答案。然而,决定分析答案的存在的条件被发现了,分析答案和它的精力水平结构与在这篇论文上面被打手势的潜力为 Schr&#246;dinger 方程被获得。根据在一个量系统的波浪功能的单个值、有限、连续的标准,作者第一通过光线的并列 r &#8594; 解决 asymptotic 解决方案并且 r &#8594; 0;第二,他们使与附近的系列答案结合的 asymptotic 答案成为不规则的奇特的邻居;然后他们比较力量系列系数,由为光线的 Schr&#246;dinger 方程的在潜在的功能的系数之中的紧张的联合推出静止州的波浪功能和相应精力水平结构的一系列分析答案;并且最后,他们讨论答案并且做结论。 展开更多
关键词 薛定谔方程 解析解 逆功率 叠加 势函数 定态波函数 电位 阳性
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On the Solutions of an Equation Involving the Smarandache Power Function SP(n)
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作者 PAN Xiao-wei 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2008年第3期437-441,共5页
为任何积极整数 n ,著名 Smarandache 力量功能 SP (n)被定义为最小的积极整数 m 以便 n|mm ,在 m 和 n 有一样的主要 divisors.The 的地方,这份报纸的主要目的正在使用基本方法学习包含 Smarandache 力量功能 SP (n)的一个方程的积... 为任何积极整数 n ,著名 Smarandache 力量功能 SP (n)被定义为最小的积极整数 m 以便 n|mm ,在 m 和 n 有一样的主要 divisors.The 的地方,这份报纸的主要目的正在使用基本方法学习包含 Smarandache 力量功能 SP (n)的一个方程的积极整数答案并且获得某有趣的 results.At 一样的时间,我们关于相关方程给一个开的问题。 展开更多
关键词 Smarandache幂函数 SP(z) 方程 整数解
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Simulation on control of beam halo-chaos by power function in the hackle periodic-focusing channel
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作者 YU Haijun WENG Jiaqiang BAI Long 《Nuclear Science and Techniques》 SCIE CAS CSCD 2008年第6期325-328,共4页
The K-V beam through a hackle periodic-focusing magnetic field is studied using the particle-core model. The beam halo-chaos is found, and a power function controller is proposed based on mechanism of halo formation a... The K-V beam through a hackle periodic-focusing magnetic field is studied using the particle-core model. The beam halo-chaos is found, and a power function controller is proposed based on mechanism of halo formation and strategy of controlling halo-chaos. Multiparticle simulation was performed to control the halo by using the power function control method. The results show that the halo-chaos and its regeneration can be eliminated effectively. We also find that the radial particle density evolvement is of uniformity at the beam’s centre as long as appropriate parameters are chosen. 展开更多
关键词 束晕混沌状态 周期性聚焦磁场 幂函数 核技术
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