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COMPLEX POWER OF HERMITE OPERATOR
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作者 丁夏畦 罗佩珠 《Acta Mathematica Scientia》 SCIE CSCD 2007年第4期689-693,共5页
In this paper the authors define complex power of Hermite operator and give some applications in Riemann Zeta function.
关键词 complex power Hermite operator Riemann conjecture
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Discussion on the Application of Complex Power Network to Software Engineering
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作者 Jiayan SONG 《International Journal of Technology Management》 2015年第1期92-93,共2页
Along with the further development of science and technology, computer hardware and the Intemet are in a rapid development, and information technology has been widely used in all fields so that complex problems are si... Along with the further development of science and technology, computer hardware and the Intemet are in a rapid development, and information technology has been widely used in all fields so that complex problems are simply solved. Because of the needs for the development, software starts to mutually integrate with complex power network, making the scale of software increase greatly. Such a growing trend of software promotes soft-ware development to go beyond a general understanding and control and thus a complex system is formed. It is necessary to strengthen the research of complex network theory, and this is a new way to help people study the complexity of software systems. In this paper, the development course of complex dynamic network is introduced simply and the use of complex power network in the software engineering is summarized. Hopefully, this paper can help the crossover study of complex power network and software engineering in the future. 展开更多
关键词 complex power Network Software Engineering Computer Application Network Model
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An In-Depth Study of Complex Power System Dynamic Behavior Characteristics for Chinese UHV Power Grid Security
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作者 Ding Daoqi State Grid Information & Telecommunication Co.,Ltd.Zhao Fang 《Electricity》 2009年第2期45-51,共7页
In this paper,a series of major policy decisions used to improve the power grid reliability,reduce the risk and losses of major power outages,and realize the modernization of 21st century power grid are discussed. The... In this paper,a series of major policy decisions used to improve the power grid reliability,reduce the risk and losses of major power outages,and realize the modernization of 21st century power grid are discussed. These decisions were adopted by American government and would also be helpful for the strategic development of Chinese power grid. It is proposed that China should take precaution,carry out security research on the overall dynamic behaviour characteristics of the UHV grid using the complexity theory,and finally provide safeguard for the Chinese UHV grid. It is also pointed out that,due to the lack of matured approaches to controll a cascading failure,the primary duty of a system operator is to work as a "watchdog" for the grid operation security,eliminate the cumulative effect and reduce the risk and losses of major cascading outages with the help of EMS and WAMS. 展开更多
关键词 EMS 2003 WAMS An In-Depth Study of complex power System Dynamic Behavior Characteristics for Chinese UHV power Grid Security
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Optimized Complex Power Quality Classifier Using One vs. Rest Support Vector Machines 被引量:1
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作者 David De Yong Sudipto Bhowmik Fernando Magnago 《Energy and Power Engineering》 2017年第10期568-587,共20页
Nowadays, power quality issues are becoming a significant research topic because of the increasing inclusion of very sensitive devices and considerable renewable energy sources. In general, most of the previous power ... Nowadays, power quality issues are becoming a significant research topic because of the increasing inclusion of very sensitive devices and considerable renewable energy sources. In general, most of the previous power quality classification techniques focused on single power quality events and did not include an optimal feature selection process. This paper presents a classification system that employs Wavelet Transform and the RMS profile to extract the main features of the measured waveforms containing either single or complex disturbances. A data mining process is designed to select the optimal set of features that better describes each disturbance present in the waveform. Support Vector Machine binary classifiers organized in a “One Vs Rest” architecture are individually optimized to classify single and complex disturbances. The parameters that rule the performance of each binary classifier are also individually adjusted using a grid search algorithm that helps them achieve optimal performance. This specialized process significantly improves the total classification accuracy. Several single and complex disturbances were simulated in order to train and test the algorithm. The results show that the classifier is capable of identifying >99% of single disturbances and >97% of complex disturbances. 展开更多
关键词 complex power Quality Optimal Feature Selection ONE vs. REST Support Vector Machine Learning Algorithms WAVELET Transform Pattern Recognition
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NEW METHOD TO ESTIMATE SCALING EXPONENTS OF POWER-LAW DEGREE DISTRIBUTION AND HIERARCHICAL CLUSTERING FUNCTION FOR COMPLEX NETWORKS
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作者 杨波 段文奇 陈忠 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第11期1475-1479,共5页
A new method and corresponding numerical procedure are introduced to estimate scaling exponents of power-law degree distribution and hierarchical clustering function for complex networks. This method can overcome the ... A new method and corresponding numerical procedure are introduced to estimate scaling exponents of power-law degree distribution and hierarchical clustering function for complex networks. This method can overcome the biased and inaccurate faults of graphical linear fitting methods commonly used in current network research. Furthermore, it is verified to have higher goodness-of-fit than graphical methods by comparing the KS (Kolmogorov-Smirnov) test statistics for 10 CNN (Connecting Nearest-Neighbor) networks. 展开更多
关键词 parameter estimation complex networks power-LAW degree distribution hierarchical modularity
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An Analytical Model of the Power Law Distributions in the Complex Network
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作者 Kosuke Takagi 《World Journal of Mechanics》 2012年第4期224-227,共4页
It is known that complex networks in nature exhibit some significant statistical features. We notice power law distributions which frequently emerge with respect to network structures of various quantities. One exampl... It is known that complex networks in nature exhibit some significant statistical features. We notice power law distributions which frequently emerge with respect to network structures of various quantities. One example is the scale-freeness which is described by the degree distribution in the power law shape. In this paper, within an analytical approach, we investigate the analytical conditions under which the distribution is reduced to the power law. We show that power law distributions are obtained without introducing conditions specific to each system or variable. Conversely, if we demand no special condition to a distribution, it is imposed to follow the power law. This result explains the universality and the ubiquitous presence of the power law distributions in complex networks. 展开更多
关键词 complex NETWORKS SCALE Free power LAW
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A novel decomposition and coordination algorithm for complex networks and its application to power grids 被引量:3
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作者 Xiangping NI Shengwei MEI 《控制理论与应用(英文版)》 EI 2008年第1期53-58,共6页
To analyze and control complex networks effectively, this paper puts forward a new kind of scheme, which takes control separately in each area and can achieve the network’s coordinated optimality. The proposed algori... To analyze and control complex networks effectively, this paper puts forward a new kind of scheme, which takes control separately in each area and can achieve the network’s coordinated optimality. The proposed algorithm is made up of two parts: the first part decomposes the network into several independent areas based on community structure and decouples the information flow and control power among areas; the second part selects the center nodes from each area with the help of the control centrality index. As long as the status of center nodes is kept on a satisfactory level in each area, the whole system is under effective control. Finally, the algorithm is applied to power grids, and the simulations prove its effectiveness. 展开更多
关键词 复杂网络 网络结构 调和算法 电力网络
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A Novel Low-Complexity Low-Latency Power Efficient Collision Detection Algorithm for Wireless Sensor Networks
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作者 Fawaz Alassery Walid K. M. Ahmed +1 位作者 Mohsen Sarraf Victor Lawrence 《Wireless Sensor Network》 2015年第6期43-75,共33页
Collision detection mechanisms in Wireless Sensor Networks (WSNs) have largely been revolving around direct demodulation and decoding of received packets and deciding on a collision based on some form of a frame error... Collision detection mechanisms in Wireless Sensor Networks (WSNs) have largely been revolving around direct demodulation and decoding of received packets and deciding on a collision based on some form of a frame error detection mechanism, such as a CRC check. The obvious drawback of full detection of a received packet is the need to expend a significant amount of energy and processing complexity in order to fully decode a packet, only to discover the packet is illegible due to a collision. In this paper, we propose a suite of novel, yet simple and power-efficient algorithms to detect a collision without the need for full-decoding of the received packet. Our novel algorithms aim at detecting collision through fast examination of the signal statistics of a short snippet of the received packet via a relatively small number of computations over a small number of received IQ samples. Hence, the proposed algorithms operate directly at the output of the receiver's analog-to-digital converter and eliminate the need to pass the signal through the entire. In addition, we present a complexity and power-saving comparison between our novel algorithms and conventional full-decoding (for select coding schemes) to demonstrate the significant power and complexity saving advantage of our algorithms. 展开更多
关键词 WIRELESS SENSOR Networks WIRELESS SENSOR Protocols COLLISION Detection ALGORITHMS power-Efficient Techniques Low complexITY ALGORITHMS
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Optimal power allocation for complex field network coding scheme with the K-th best relay selection
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作者 Xi CAI Pingzhi FAN Qingchun CHEN 《Journal of Modern Transportation》 2012年第4期255-260,共6页
Wireless relay and network coding are two critical techniques to increase the reliability and throughput of wireless cooperative communication systems. In this paper, a complex field network coding (CFNC) scheme wit... Wireless relay and network coding are two critical techniques to increase the reliability and throughput of wireless cooperative communication systems. In this paper, a complex field network coding (CFNC) scheme with the K-th best relay selection (KBS) is proposed and investigated, wherein the K-th best relay is selected to forward the multiplexed signal to the destination. First, the upper bound of the symbol error probability (SEP), the diversity order, and the coding gain are derived for the CFNC scheme with KBS. Then, the coding gain is utilized as the optimized cri- terion to determine the optimal power allocation. It is validated through analysis and simulation that the CFNC scheme with KBS can achieve full diversity only when K=I, while the diversity order decreases with increasing parameter K, and the optimal power allocation can significantly improve the performance of the CFNC scheme with KBS. 展开更多
关键词 complex field network coding the K-th best relay selection power allocation
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基于多目标优化的复杂热电联产系统运行规划
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作者 陈坚红 王国雲 +2 位作者 左克清 张洪坤 鲍彦克 《浙江大学学报(工学版)》 北大核心 2026年第1期148-157,共10页
热电厂的扩建、改造和升级显著增加了热电联产系统在机组数量、种类及性能劣化程度等方面的复杂性.针对复杂热电联产系统的运行规划,综合考虑机组在实际运行过程中的启停状态、爬坡速率等影响因素,构建基于能效、㶲、经济、环境等的多目... 热电厂的扩建、改造和升级显著增加了热电联产系统在机组数量、种类及性能劣化程度等方面的复杂性.针对复杂热电联产系统的运行规划,综合考虑机组在实际运行过程中的启停状态、爬坡速率等影响因素,构建基于能效、㶲、经济、环境等的多目标优化模型.引入熵权法客观地分配各目标的权重,将多目标优化问题转化为单目标优化问题;采用动态规划算法进行求解,确保最优解的确定性和客观性.以某热电厂的复杂热电联产系统为例,随机选取24 h的热电负荷需求进行运行规划和计算分析,并将优化结果与原设计方案进行对比,结果表明优化计算后运行成本降低了7.96万元/d.所提模型能够有效地提升复杂热电联产系统运行的经济性与可靠性. 展开更多
关键词 复杂热电联产系统 多目标优化 运行规划 熵权法 动态规划法
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瞬态信号的双树复小波Power-Law检测
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作者 董华玉 张晓兵 +1 位作者 文钢 玄兆林 《数据采集与处理》 CSCD 北大核心 2009年第1期23-27,共5页
为克服离散小波变换平移不变性差的不足,通过构造的Hilbert变换对滤波器组,实现了双树复小波变换。建立了基于复小波变换系数的Power-Law检测器。推导了检测统计量的渐近性能和偏移系数,由输入信噪比损失给出了检测器参数的选择方法。... 为克服离散小波变换平移不变性差的不足,通过构造的Hilbert变换对滤波器组,实现了双树复小波变换。建立了基于复小波变换系数的Power-Law检测器。推导了检测统计量的渐近性能和偏移系数,由输入信噪比损失给出了检测器参数的选择方法。利用仿真与实测数据进行了试验,并与基于离散小波变换的Power-Law检测器进行了比较。本文提出的小波方法能很好实现平移不变性,建立的检测器具有更大的偏移系数,在相同的信噪比和虚警概率下能够得到更高的检测概率。 展开更多
关键词 信号检测 瞬态信号 双树复小波 Hilbert变换对 power-Law检测
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A new modeling scheme for powered parafoil unmanned aerial vehicle platforms: Theory and experiments 被引量:5
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作者 Bingbing LI Yuqing HE +1 位作者 Jianda HAN Jizhong XIAO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第11期2466-2479,共14页
A novel framework is established for accurate modeling of Powered Parafoil Unmanned Aerial Vehicle(PPUAV). The model is developed in the following three steps: obtaining a linear dynamic model, simplifying the model s... A novel framework is established for accurate modeling of Powered Parafoil Unmanned Aerial Vehicle(PPUAV). The model is developed in the following three steps: obtaining a linear dynamic model, simplifying the model structure, and estimating the model mismatch due to model variance and external disturbance factors. First, a six degree-of-freedom linear model, or the structured model, is obtained through dynamic establishment and linearization. Second, the data correlation analysis is adopted to determine the criterion for proper model complexity and to simplify the structured model. Next, an active model is established, combining the simplified model with the model mismatch estimator. An adapted Kalman filter is utilized for the real-time estimation of states and model mismatch. We finally derive a linear system model while taking into account of model variance and external disturbance. Actual flight tests verify the effectiveness of our active model in different flight scenarios. 展开更多
关键词 Active model Data correlation analysis Model complexity powered parafoil State estimation Unmanned aerial vehicle(UAV)
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Power Balance of Multi-Harmonic Components in Nonlinear Network 被引量:6
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作者 Binghua Huang Xiaoyang He 《Journal of Modern Physics》 2014年第14期1321-1331,共11页
The main harmonic components in nonlinear differential equations can be solved by using the harmonic balance principle. The nonlinear coupling relation among various harmonics can be found by balance theorem of freque... The main harmonic components in nonlinear differential equations can be solved by using the harmonic balance principle. The nonlinear coupling relation among various harmonics can be found by balance theorem of frequency domain. The superhet receiver circuits which are described by nonlinear differential equation of comprising even degree terms include three main harmonic components: the difference frequency and two signal frequencies. Based on the nonlinear coupling relation, taking superhet circuit as an example, this paper demonstrates that the every one of three main harmonics in networks must individually observe conservation of complex power. The power of difference frequency is from variable-frequency device. And total dissipative power of each harmonic is equal to zero. These conclusions can also be verified by the traditional harmonic analysis. The oscillation solutions which consist of the mixture of three main harmonics possess very long oscillation period, the spectral distribution are very tight, similar to evolution from doubling period leading to chaos. It can be illustrated that the chaos is sufficient or infinite extension of the oscillation period. In fact, the oscillation solutions plotted by numerical simulation all are certainly a periodic function of discrete spectrum. When phase portrait plotted hasn’t finished one cycle, it is shown as aperiodic chaos. 展开更多
关键词 FREQUENCY DOMAIN complex power DIFFERENCE FREQUENCY Nonlinear Coupling CHAOS HARMONIC OSCILLATION
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An optimized framework for degree distribution in LT codes based on power law
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作者 Asim Muhammad Choi GoangSeog 《Journal of Central South University》 SCIE EI CAS 2013年第10期2693-2699,共7页
LT codes are practical realization of digital fountain codes, which provides the concept of rateless coding. In this scheme, encoded symbols are generated infinitely from k information symbols. Decoder uses only(1+α)... LT codes are practical realization of digital fountain codes, which provides the concept of rateless coding. In this scheme, encoded symbols are generated infinitely from k information symbols. Decoder uses only(1+α)k number of encoded symbols to recover the original information. The degree distribution function in the LT codes helps to generate a random graph also referred as tanner graph. The artifact of tanner graph is responsible for computational complexity and overhead in the LT codes. Intuitively, a well designed degree distribution can be used for an efficient implementation of LT codes. The degree distribution function is studied as a function of power law, and LT codes are classified into two different categories: SFLT and RLT codes. Also, two different degree distributions are proposed and analyzed for SFLT codes which guarantee optimal performance in terms of computational complexity and overhead. 展开更多
关键词 FOUNTAIN CODES DEGREE distribution OVERHEAD computational complexITY power LAW
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Intrinsic Noise Monitoring of Complex Systems 被引量:2
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作者 Oliver Szasz Gyula Peter Szigeti Andras Szasz 《Open Journal of Biophysics》 2017年第4期197-215,共19页
The power-density function of the noise spectrum of open and complex systems changes by the power of frequency. We show that the fluctuation origin and the noise-powered description are equivalent to describe the colo... The power-density function of the noise spectrum of open and complex systems changes by the power of frequency. We show that the fluctuation origin and the noise-powered description are equivalent to describe the colored noise power density. Based on this, we introduce a scale-independent invariant for monitoring the dynamics of the complex system. The monitoring of the noise spectrum of the system specifies the forecast of failure, the timing of desired regular corrections and/or the assessed operation life of the system, indicating the possible faults before it happens, predicting deterioration like wear/tear, fatigue in the still properly working system. These considerations are highly applicable to living systems and their preventive care. 展开更多
关键词 power Density complex Systems REGULAR Maintenance System INVARIANT FLUCTUATION DIAGNOSTICS
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S-curve networks and an approximate method for estimating degree distributions of complex networks 被引量:2
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作者 郭进利 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第12期68-74,共7页
In the study of complex networks almost all theoretical models have the property of infinite growth, but the size of actual networks is finite. According to statistics from the China Internet IPv4 (Internet Protocol ... In the study of complex networks almost all theoretical models have the property of infinite growth, but the size of actual networks is finite. According to statistics from the China Internet IPv4 (Internet Protocol version 4) addresses, this paper proposes a forecasting model by using S curve (logistic curve). The growing trend of IPv4 addresses in China is forecasted. There are some reference values for optimizing the distribution of IPv4 address resource and the development of IPv6. Based on the laws of IPv4 growth, that is, the bulk growth and the finitely growing limit, it proposes a finite network model with a bulk growth. The model is said to be an S-curve network. Analysis demonstrates that the analytic method based on uniform distributions (i.e., Barabasi-Albert method) is not suitable for the network. It develops an approximate method to predict the growth dynamics of the individual nodes, and uses this to calculate analytically the degree distribution and the scaling exponents. The analytical result agrees with the simulation well, obeying an approximately power-law form. This method can overcome a shortcoming of Barabasi-Albert method commonly used in current network research. 展开更多
关键词 complex network scale-free network power-law distribution IPv4 standard logistic curve
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THE STUDY ON DEGREE DISTRIBUTION PROPERTY OF COMPLEX NETWORK BASED ON COOPERATIVE COMMUNICATION 被引量:1
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作者 Xie Weihao Chen Huimin +1 位作者 Yang Xiumei Xiong Yong 《Journal of Electronics(China)》 2010年第2期224-229,共6页
Complex networks have been widely studied. Recently,many results show that the degree distributions of some large networks follow the form of power-law and these networks possess better robustness against random nodes... Complex networks have been widely studied. Recently,many results show that the degree distributions of some large networks follow the form of power-law and these networks possess better robustness against random nodes failure. As an effective technology on combating the channel fading,wireless cooperative communication is becoming one of the most important methods to improve the wireless communication performances. In this paper,the complex network models based on cooperative communication and non-cooperative communication are established; and the degree distribution properties for them are studied. The simulation results show that the degree distributions of these networks also follow the form of power-law,which means that the addition of cooperative communi-cation links will not change the property of degree distribution and then these networks will possess better robustness against random nodes failure as well. 展开更多
关键词 complex networks Cooperative communication Degree distribution power-LAW
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Logistic Mapping-Based Complex Network Modeling
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作者 Xiaoling Yu Zhen Jia Xiangguo Jian 《Applied Mathematics》 2013年第11期1158-1562,共405页
In this paper, a new topological approach for studying an integer sequence constructed from Logistic mapping is proposed. By evenly segmenting [0,1]?into N non-overlapping subintervals which is marked as , representin... In this paper, a new topological approach for studying an integer sequence constructed from Logistic mapping is proposed. By evenly segmenting [0,1]?into N non-overlapping subintervals which is marked as , representing the nodes identities, a network is constructed for analysis. Wherein the undirected edges symbolize their relation of adjacency in an integer sequence obtained from the Logistic mapping and the top integral function. By observation, we find that nodes’ degree changes with different values of??instead of the initial value—X0, and the degree distribution presents the characteristics of scale free network, presenting power law distribution. The results presented in this paper provide some insight into degree distribution of the network constructed from integer sequence that may help better understanding of the nature of Logistic mapping. 展开更多
关键词 complex Network LOGISTIC MAPPING power LAW DISTRIBUTION
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CAXA和Power mill在复杂曲面文字雕刻加工中的应用 被引量:1
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作者 姜广美 《农业装备技术》 2015年第5期40-43,共4页
以在复杂曲面文字雕刻加工为例,介绍了利用CAXA造型和Power mill进行自动编程、加工策略、工艺参数、三维仿真及后置处理的过程,通过加工,优势明显,提高了零件质量,缩短了时间等。
关键词 CAXA power MILL 复杂曲面 文字雕刻 数控加工
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Mobile user forecast and power-law acceleration invariance of scale-free networks 被引量:1
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作者 郭进利 郭曌华 刘雪娇 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第11期548-555,共8页
This paper studies and predicts the number growth of China's mobile users by using the power-law regression. We find that the number growth of the mobile users follows a power law. Motivated by the data on the evolut... This paper studies and predicts the number growth of China's mobile users by using the power-law regression. We find that the number growth of the mobile users follows a power law. Motivated by the data on the evolution of the mobile users, we consider scenarios of self-organization of accelerating growth networks into scale-free structures and propose a directed network model, in which the nodes grow following a power-law acceleration. The expressions for the transient and the stationary average degree distributions are obtained by using the Poisson process. This result shows that the model generates appropriate power-law connectivity distributions. Therefore, we find a power-law acceleration invariance of the scale-free networks. The numerical simulations of the models agree with the analytical results well. 展开更多
关键词 mobile user forecast power-law accelerating growth complex networks scale-free net-works
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