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Ramsey numbers of edge-critical graphs versus large generalized fans
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作者 Taiping Jiang Xinmin Hou 《中国科学技术大学学报》 北大核心 2025年第5期62-66,61,I0002,共7页
Given two graphs G and H,the Ramsey number R(G,H)is the smallest positive integer N such that every 2-coloring of the edges of K_(N)contains either a red G or a blue H.Let K_(N-1)■K_(1,k)be the graph obtained from K_... Given two graphs G and H,the Ramsey number R(G,H)is the smallest positive integer N such that every 2-coloring of the edges of K_(N)contains either a red G or a blue H.Let K_(N-1)■K_(1,k)be the graph obtained from K_(N-1)by adding anew vertexνconnecting k vertices of K_(N-1).A graph G withχ(G)=k+1 is called edge-critical if G contains an edge e such thatχ(G-e)=k.A considerable amount of research has been conducted by previous scholars on Ramsey numbers ofgraphs.In this study,we show that for an edge-critical graph G with x(G)=k+1,when k≥2,1≥2,and n is sufficiently large,R(G,K_(1)+nK_(t))=knt+1 and r,(G,K_(1)+nK_(t))=(k-1)nt+1. 展开更多
关键词 Ramsey number color critical graph generalized fan
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Temperature control for liquid-cooled fuel cells based on fuzzy logic and variable-gain generalized supertwisting algorithm
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作者 CHEN Lin JIA Zhi-huan +1 位作者 DING Tian-wei GAO Jin-wu 《控制理论与应用》 北大核心 2025年第8期1596-1605,共10页
The liquid cooling system(LCS)of fuel cells is challenged by significant time delays,model uncertainties,pump and fan coupling,and frequent disturbances,leading to overshoot and control oscillations that degrade tempe... The liquid cooling system(LCS)of fuel cells is challenged by significant time delays,model uncertainties,pump and fan coupling,and frequent disturbances,leading to overshoot and control oscillations that degrade temperature regulation performance.To address these challenges,we propose a composite control scheme combining fuzzy logic and a variable-gain generalized supertwisting algorithm(VG-GSTA).Firstly,a one-dimensional(1D)fuzzy logic controler(FLC)for the pump ensures stable coolant flow,while a two-dimensional(2D)FLC for the fan regulates the stack temperature near the reference value.The VG-GSTA is then introduced to eliminate steady-state errors,offering resistance to disturbances and minimizing control oscillations.The equilibrium optimizer is used to fine-tune VG-GSTA parameters.Co-simulation verifies the effectiveness of our method,demonstrating its advantages in terms of disturbance immunity,overshoot suppression,tracking accuracy and response speed. 展开更多
关键词 liquid-cooled fuel cell temperature control generalized supertwisting algorithm fuzzy control equilibrium optimizer
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An improved model of the Pasternak foundation beam umbrella arch considering the generalized shear force
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作者 CHEN Lei JIA Chao-jun +3 位作者 LEI Ming-feng HE Yan-chun SHI Cheng-hua LI Ao 《Journal of Central South University》 2025年第4期1503-1519,共17页
The existing analytical models for umbrella arch method(UAM)based on elastic foundation beams often overlook the influence of the surrounding soil beyond the beam edges on the shear stresses acting on the beam.Consequ... The existing analytical models for umbrella arch method(UAM)based on elastic foundation beams often overlook the influence of the surrounding soil beyond the beam edges on the shear stresses acting on the beam.Consequently,such models fail to adequately reflect the continuity characteristics of soil deformation.Leveraging the Pasternak foundation-Euler beam model,this study considers the generalized shear force on the beam to account for the influence of soil outside the beam ends on the shear stress.An analytical model for the deformation and internal forces of finite-length beams subjected to arbitrary loads is derived based on the initial parameter method under various conditions.The mechanical model of the elastic foundation beam for advanced umbrella arch under typical tunnel excavation cycles is established,yielding analytical solutions for the longitudinal response of the umbrella arch.The reliability of the analytical model is verified with the existing test data.The improved model addresses anomalies in existing models,such as abnormal upward deformation in the loosened segment and maximum deflection occurring within the soil mass.Additionally,dimensionless characteristic parameters reflecting the relative stiffness between the umbrella arch structure and the foundation soil are proposed.Results indicate that the magnitude of soil characteristic parameters significantly influences the deformation and internal forces of the umbrella arch.Within common ranges of soil values,the maximum deformation and internal forces of the umbrella arch under semi-logarithmic coordinates exhibit nearly linear decay with decreasing soil characteristic parameters.The impact of tunnel excavation height on the stress of unsupported sections of the umbrella arch is minor,but it is more significant for umbrella arch buried within the soil mass.Conversely,the influence of tunnel excavation advance on the umbrella arch is opposite. 展开更多
关键词 elastic foundation beam Pasternak foundation generalized shear umbrella arch analytical model
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Generalized multiple-mode prolate spheroidal wave functions multi-carrier waveform with index modulation
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作者 XU Zhichao LU Faping +5 位作者 ZHANG Lifan YANG Dongkai LIU Chuanhui KANG Jiafang AN Qi ZHANG Zhilin 《Journal of Systems Engineering and Electronics》 2025年第2期311-322,共12页
A generalized multiple-mode prolate spherical wave functions (PSWFs) multi-carrier with index modulation approach is proposed with the purpose of improving the spectral efficiency of PSWFs multi-carrier systems. The p... A generalized multiple-mode prolate spherical wave functions (PSWFs) multi-carrier with index modulation approach is proposed with the purpose of improving the spectral efficiency of PSWFs multi-carrier systems. The proposed method,based on the optimized multi-index modulation, does not limit the number of signals in the first and second constellations and abandons the concept of limiting the number of signals in different constellations. It successfully increases the spectrum efficiency of the system while expanding the number of modulation symbol combinations and the index dimension of PSWFs signals. The proposed method outperforms the PSWFs multi-carrier index modulation method based on optimized multiple indexes in terms of spectrum efficiency, but at the expense of system computational complexity and bit error performance. For example, with n=10 subcarriers and a bit error rate of 1×10^(-5),spectral efficiency can be raised by roughly 12.4%. 展开更多
关键词 prolate spherical wave function(PSWF) generalized multiple-mode index modulation spectral efficiency.
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Application of Fractal Technology in the Generative Design of Chaoshan Drawnwork Patterns
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作者 CHEN Jia-jun ZHANG Ya CHEN Zhao-yang 《印刷与数字媒体技术研究》 北大核心 2025年第5期179-194,共16页
Chaoshan drawnwork handkerchief design exhibits self-similarity and fractal characteristics due to their grid-based structure,overall symmetry,and the way local motifs reflect the whole pattern.To explore the potentia... Chaoshan drawnwork handkerchief design exhibits self-similarity and fractal characteristics due to their grid-based structure,overall symmetry,and the way local motifs reflect the whole pattern.To explore the potential of fractals in traditional textile design,a fractal-based generative framework was proposed for efficiently creating drawnwork patterns suitable for practical handicraft production.The research was initiated with an analysis of the structural composition of center,skeleton,and filler motifs extracted from a pattern sample library.Based on this hierarchical classification,the box-counting method was employed to calculate their respective fractal dimensions.Building on fractal art theory,generative algorithms,and studies on the application of Ultra Fractal,a Chaoshan drawnwork fractal design model was established.Using this model,51 drawnwork fractal patterns and 153 handkerchief patterns were generated.These patterns were subsequently applied in real-world production to validate the feasibility and value of fractal techniques in textile design. 展开更多
关键词 Chaoshan drawnwork Fractal pattern generative design Cultural heritage
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PM_(2.5) probabilistic forecasting system based on graph generative network with graph U-nets architecture
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作者 LI Yan-fei YANG Rui +1 位作者 DUAN Zhu LIU Hui 《Journal of Central South University》 2025年第1期304-318,共15页
Urban air pollution has brought great troubles to physical and mental health,economic development,environmental protection,and other aspects.Predicting the changes and trends of air pollution can provide a scientific ... Urban air pollution has brought great troubles to physical and mental health,economic development,environmental protection,and other aspects.Predicting the changes and trends of air pollution can provide a scientific basis for governance and prevention efforts.In this paper,we propose an interval prediction method that considers the spatio-temporal characteristic information of PM_(2.5)signals from multiple stations.K-nearest neighbor(KNN)algorithm interpolates the lost signals in the process of collection,transmission,and storage to ensure the continuity of data.Graph generative network(GGN)is used to process time-series meteorological data with complex structures.The graph U-Nets framework is introduced into the GGN model to enhance its controllability to the graph generation process,which is beneficial to improve the efficiency and robustness of the model.In addition,sparse Bayesian regression is incorporated to improve the dimensional disaster defect of traditional kernel density estimation(KDE)interval prediction.With the support of sparse strategy,sparse Bayesian regression kernel density estimation(SBR-KDE)is very efficient in processing high-dimensional large-scale data.The PM_(2.5)data of spring,summer,autumn,and winter from 34 air quality monitoring sites in Beijing verified the accuracy,generalization,and superiority of the proposed model in interval prediction. 展开更多
关键词 PM_(2.5)interval forecasting graph generative network graph U-Nets sparse Bayesian regression kernel density estimation spatial-temporal characteristics
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基于Generalized LASSO模型的长江寸滩站年均径流突变研究 被引量:2
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作者 贺冉冉 陈元芳 +1 位作者 黄琴 吴晶 《河海大学学报(自然科学版)》 CAS CSCD 北大核心 2017年第4期358-364,共7页
为了区分水文时间序列的趋势和跳跃变异,将基于L_1范数正则化技术的generalized LASSO模型应用于水文序列变异识别。经过识别,发现长江寸滩水文站年平均流量序列在1969年发生了向下的均值跃变。此外,趋势分析表明无论是跃变前后的子序... 为了区分水文时间序列的趋势和跳跃变异,将基于L_1范数正则化技术的generalized LASSO模型应用于水文序列变异识别。经过识别,发现长江寸滩水文站年平均流量序列在1969年发生了向下的均值跃变。此外,趋势分析表明无论是跃变前后的子序列还是剔除跳跃成分的整个序列,均未检出显著的趋势,这说明对寸滩水文站年平均流量序列的跳跃变异假设是合理的。基于generalized LASSO模型的结果与其他突变检测方法结果进行比较,所得结论是一致的。 展开更多
关键词 水文时间序列 变异识别 跳跃点 趋势分析 generalized LASSO 长江上游寸滩水文站
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Research on Generalized Computing Systems 被引量:3
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作者 Min, Yao Jianhua, Luo 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第3期39-43,共5页
This paper presents a kind of artificial intelligent system-generalized computing system (GCS for short), and introduces its mathematical description, implement problem and learning problem.
关键词 Artificial intelligence generalized computing generalized computing systems generalized learning
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Linear generalized synchronization of chaotic systems with uncertain parameters 被引量:7
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作者 Jia Zhen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2008年第4期779-784,共6页
A more general form of projective synchronization, so called linear generalized synchronization (LGS) is proposed, which includes the generalized projective synchronization (GPS) and the hybrid projective synchron... A more general form of projective synchronization, so called linear generalized synchronization (LGS) is proposed, which includes the generalized projective synchronization (GPS) and the hybrid projective synchronization (HPS) as its special cases, Based on the adaptive technique and Lyapunov stability theory, a general method for achieving the LGS between two chaotic or hyperehaotic systems with uncertain parameters in any scaling matrix is presented. Some numerical simulations are provided to show the effectiveness and feasibility of the proposed synchronization method. 展开更多
关键词 generalized synchronization chaotic system hyperchaotic system uncertain parameter adaptive technique.
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NONEMPTY INTERSECTION THEOREMS AND SYSTEM OF GENERALIZED VECTOR EQUILIBRIUM PROBLEMS IN PRODUCT G-CONVEX SPACES 被引量:3
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作者 丁协平 《应用数学和力学》 EI CSCD 北大核心 2004年第6期563-571,共9页
By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established... By using an existence theorems of maximal elements for a family of set-valued mappings in G-convex spaces due to the author, some new nonempty intersection theorems for a family of set-valued mappings were established in noncompact product G-convex spaces. As applications, some equilibrium existence theorems for a system of generalized vector equilibrium problems were proved in noncompact product G-convex spaces. These theorems unify, improve and generalize some important known results in literature. 展开更多
关键词 集值映象组 非空交定理 广义矢量平衡问题组 乘积G凸空间
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Dynamic weighted voting for multiple classifier fusion:a generalized rough set method 被引量:9
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作者 Sun Liang Han Chongzhao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第3期487-494,共8页
To improve the performance of multiple classifier system, a knowledge discovery based dynamic weighted voting (KD-DWV) is proposed based on knowledge discovery. In the method, all base classifiers may be allowed to ... To improve the performance of multiple classifier system, a knowledge discovery based dynamic weighted voting (KD-DWV) is proposed based on knowledge discovery. In the method, all base classifiers may be allowed to operate in different measurement/feature spaces to make the most of diverse classification information. The weights assigned to each output of a base classifier are estimated by the separability of training sample sets in relevant feature space. For this purpose, some decision tables (DTs) are established in terms of the diverse feature sets. And then the uncertainty measures of the separability are induced, in the form of mass functions in Dempster-Shafer theory (DST), from each DTs based on generalized rough set model. From the mass functions, all the weights are calculated by a modified heuristic fusion function and assigned dynamically to each classifier varying with its output. The comparison experiment is performed on the hyperspectral remote sensing images. And the experimental results show that the performance of the classification can be improved by using the proposed method compared with the plurality voting (PV). 展开更多
关键词 multiple classifier fusion dynamic weighted voting generalized rough set hyperspectral.
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Statistical analysis of generalized exponential distribution under progressive censoring with binomial removals 被引量:11
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作者 Weian Yan Yimin Shi +1 位作者 Baowei Song Zhaoyong Mao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第4期707-714,共8页
The estimation of generalized exponential distribution based on progressive censoring with binomial removals is presented, where the number of units removed at each failure time follows a binomial distribution. Maximu... The estimation of generalized exponential distribution based on progressive censoring with binomial removals is presented, where the number of units removed at each failure time follows a binomial distribution. Maximum likelihood estimators of the parameters and their confidence intervals are derived. The expected time required to complete the life test under this censoring scheme is investigated. Finally, the numerical examples are given to illustrate some theoretical results by means of Monte-Carlo simulation. 展开更多
关键词 binomial removal progressive censoring maximumlikelihood estimator expected experiment time generalized exponential distribution.
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Stability of Motion for Generalized Birkhoffian Systems 被引量:5
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作者 张毅 《Defence Technology(防务技术)》 SCIE EI CAS 2010年第3期161-165,共5页
The problem on the stability of motion for a generalized Birkhoffian system was studied. The disturbed equations of motion and their first approximation for the system were established. The criterion of stability of m... The problem on the stability of motion for a generalized Birkhoffian system was studied. The disturbed equations of motion and their first approximation for the system were established. The criterion of stability of motion for the system was set up by using Liapunov's first approximation theory. Based on the theory of Noether symmetry,the Liapunov's function was constructed,and the criterion of stability of motion for the system was also set up by using Liapunov's direct method. Two examples were given to illustrate the application of the results. 展开更多
关键词 applied mathematics generalized Birkhoffian system stability of motion Noether symmetry
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New deghosting method based on generalized triangulation 被引量:5
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作者 Bai Jing Wang Guohong Xiu Jianjuan Wang Xiaobo 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2009年第3期504-511,共8页
A new deghosting method based on the generalized triangulation is presented. First, two intersection points corresponding to the emitter position are obtained by utilizing two azimuth angles and two elevation angles f... A new deghosting method based on the generalized triangulation is presented. First, two intersection points corresponding to the emitter position are obtained by utilizing two azimuth angles and two elevation angles from two jammed 3-D radars (or 2-D passive sensors). Then, hypothesis testing based deghosting method in the multiple target scenarios is proposed using the two intersection points. In order to analyze the performance of the proposed method, the correct association probability of the true targets and the incorrect association probability of the ghost targets are defined. Finally, the Monte Carlo simulations are given for the proposed method compared with the hinge angle method in the cases of both two and three radars. The simulation results show that the proposed method has better performance than the hinge angle method in three radars case. 展开更多
关键词 deghosting generalized triangulation hinge angle distributed radar network hypothesis testing
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Generalized thermoelastic interaction in functional graded material with fractional order three-phase lag heat transfer 被引量:4
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作者 Ibrahim A.Abbas 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第5期1606-1613,共8页
The present work is concerned with the solution of a problem on thermoelastic interactions in a functional graded material due to thermal shock in the context of the fractional order three-phase lag model. The governi... The present work is concerned with the solution of a problem on thermoelastic interactions in a functional graded material due to thermal shock in the context of the fractional order three-phase lag model. The governing equations of fractional order generalized thermoelasticity with three-phase lag model for functionally graded materials(FGM)(i.e., material with spatially varying material properties) are established. The analytical solution in the transform domain is obtained by using the eigenvalue approach.The inversion of Laplace transform is done numerically. The graphical results indicate that the fractional parameter has significant effects on all the physical quantities. Thus, we can consider the theory of fractional order generalized thermoelasticity an improvement on studying elastic materials. 展开更多
关键词 three-phase lag model fimctionally graded materials fractional calculus generalized thermoelasticity
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Inference for dependence competing risks from bivariate exponential model under generalized progressive hybrid censoring with partially observed failure causes 被引量:2
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作者 WANG Liang LI Huanyu MA Jin'ge 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第1期201-208,共8页
Inference are considered for the dependence competing risks model by using the Marshal-Olkin bivariate exponential distribution. Under generalized progressively hybrid censoring with partially observed failure causes,... Inference are considered for the dependence competing risks model by using the Marshal-Olkin bivariate exponential distribution. Under generalized progressively hybrid censoring with partially observed failure causes, the maximum likelihood estimators are established, and the approximate confidence intervals are also constructed via the observed Fisher information matrix.Moreover, Bayes estimates and highest probability density credible intervals are presented and the importance sampling technique is used to compute corresponding results. Finally, the numerical analysis is proposed for illustration. 展开更多
关键词 DEPENDENCE competing risk generalized PROGRESSIVE HYBRID CENSORING BIVARIATE exponential distribution Bayesian inference.
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Image decomposition and staircase effect reduction based on total generalized variation 被引量:2
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作者 Jianlou Xu Xiangchu Feng +1 位作者 Yan Hao Yu Han 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第1期168-174,共7页
Total variation (TV) is widely applied in image process-ing. The assumption of TV is that an image consists of piecewise constants, however, it suffers from the so-cal ed staircase effect. In order to reduce the sta... Total variation (TV) is widely applied in image process-ing. The assumption of TV is that an image consists of piecewise constants, however, it suffers from the so-cal ed staircase effect. In order to reduce the staircase effect and preserve the edges when textures of image are extracted, a new image decomposition model is proposed in this paper. The proposed model is based on the to-tal generalized variation method which involves and balances the higher order of the structure. We also derive a numerical algorithm based on a primal-dual formulation that can be effectively imple-mented. Numerical experiments show that the proposed method can achieve a better trade-off between noise removal and texture extraction, while avoiding the staircase effect efficiently. 展开更多
关键词 total variation (TV) image decomposition staircaseeffect total generalized variation.
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Improved theory of generalized meteo-ballistic weighting factor functions and their use 被引量:1
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作者 Vladimir CECH Jiri JEVICKY 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2016年第3期242-254,共13页
It follows from the analysis of artillery fire errors that approximately two-thirds of the inaccuracy of indirect artillery fire is caused by inaccuracies in the determination of the meteo parameters included in fire ... It follows from the analysis of artillery fire errors that approximately two-thirds of the inaccuracy of indirect artillery fire is caused by inaccuracies in the determination of the meteo parameters included in fire error budget model.Trajectories calculated under non-standard conditions are considered to be perturbed.The tools utilized for the analysis of perturbed trajectories are weighting factor functions(WFFs)which are a special kind of sensitivity functions.WFFs are used for calculation of meteo ballistic elements B(ballistic wind w B,densityρB,virtual temperatureτB,pressure p B)as well.We have found that the existing theory of WFF calculation has several significant shortcomings.The aim of the article is to present a new,improved theory of generalized WFFs that eliminates the deficiencies found.Using this theory will improve methods for designing firing tables,fire control systems algorithms,and meteo message generation algorithms. 展开更多
关键词 EXTERIOR BALLISTIC Non-standard projectile trajectory Perturbation Meteoconditions Sensitivity FUNCTION (generalized) weighting (factor) function(curve) (generalized) EFFECT FUNCTION Norm EFFECT
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Electricity price forecasting using generalized regression neural network based on principal components analysis 被引量:1
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作者 牛东晓 刘达 邢棉 《Journal of Central South University》 SCIE EI CAS 2008年第S2期316-320,共5页
A combined model based on principal components analysis (PCA) and generalized regression neural network (GRNN) was adopted to forecast electricity price in day-ahead electricity market. PCA was applied to mine the mai... A combined model based on principal components analysis (PCA) and generalized regression neural network (GRNN) was adopted to forecast electricity price in day-ahead electricity market. PCA was applied to mine the main influence on day-ahead price, avoiding the strong correlation between the input factors that might influence electricity price, such as the load of the forecasting hour, other history loads and prices, weather and temperature; then GRNN was employed to forecast electricity price according to the main information extracted by PCA. To prove the efficiency of the combined model, a case from PJM (Pennsylvania-New Jersey-Maryland) day-ahead electricity market was evaluated. Compared to back-propagation (BP) neural network and standard GRNN, the combined method reduces the mean absolute percentage error about 3%. 展开更多
关键词 ELECTRICITY PRICE forecasting generalized regression NEURAL NETWORK principal COMPONENTS analysis
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Linear complexity and autocorrelation of a new class of binary generalized cyclotomic sequences of order two and length pqr 被引量:1
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作者 JIA Wenjuan GAO Juntao ZHANG Peng 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第4期651-661,共11页
Cyclotomic sequences have good cryptographic properties and are closely related to difference sets.This paper proposes a new class of binary generalized cyclotomic sequences of order two and length pqr.Its linear comp... Cyclotomic sequences have good cryptographic properties and are closely related to difference sets.This paper proposes a new class of binary generalized cyclotomic sequences of order two and length pqr.Its linear complexity,minimal polynomial,and autocorrelation are investigated.The results show that these sequences have a large linear complexity when 2∈D1,which means they can resist the Berlekamp-Massey attack.Furthermore,the autocorrelation values are close to 0 with a probability of approximately 1?1/r.Therefore,when r is a big prime,the new sequence has a good autocorrelation. 展开更多
关键词 generalized cyclotomic sequence linear complexity MINIMAL POLYNOMIAL AUTOCORRELATION value.
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