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Redefined Extended Cubic B-Spline Functions for Numerical Solution of Time-Fractional Telegraph Equation
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作者 Muhammad Amin Muhammad Abbas +2 位作者 Dumitru Baleanu Muhammad Kashif Iqbal Muhammad Bilal Riaz 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第4期361-384,共24页
This work is concerned with the application of a redefined set of extended uniform cubic B-spline(RECBS)functions for the numerical treatment of time-fractional Telegraph equation.The presented technique engages finit... This work is concerned with the application of a redefined set of extended uniform cubic B-spline(RECBS)functions for the numerical treatment of time-fractional Telegraph equation.The presented technique engages finite difference formulation for discretizing the Caputo time-fractional derivatives and RECBS functions to interpolate the solution curve along the spatial grid.Stability analysis of the scheme is provided to ensure that the errors do not amplify during the execution of the numerical procedure.The derivation of uniform convergence has also been presented.Some computational experiments are executed to verify the theoretical considerations.Numerical results are compared with the existing schemes and it is concluded that the present scheme returns superior outcomes on the topic. 展开更多
关键词 Extended cubic b-spline redefined extended cubic b-spline time fractional telegraph equation caputo fractional derivative finite difference method CONVERGENCE
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Fingerprint Representation Methods Based on B-Spline Functions
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作者 Ruan Ke Xia De-lin Yan Pu-liu 《Wuhan University Journal of Natural Sciences》 EI CAS 2004年第2期193-197,共5页
The global characteristics of a fingerprint image such as the ridge shape and ridge topology are often ignored in most automatic fingerprint verification system.In this paper,a new representative method based on B-Spl... The global characteristics of a fingerprint image such as the ridge shape and ridge topology are often ignored in most automatic fingerprint verification system.In this paper,a new representative method based on B-Spline curve is proposed to address this problem.The resultant B-Spline curves can represent the global characteristics completely and the curves are analyzable and precise.An algorithm is also proposed to extract the curves from the fingerprint image.In addition to preserve the most information of the fingerprint image,the knot-points number of the B-Spline curve is reduced to minimum in this algorithm.At the same time,the influence of the fingerprint image noise is discussed.In the end,an example is given to demonstrate the effectiveness of the representation method.Key words fingerprint matching-B-spline interpolation-knots detection-parameterization-boundary condition CLC number TP 391.41 Foundation item:Supported by the National Natural Science Foundation of China(90200400)and Wuhan Technology Committee(991009185G)Biography:Ruan Ke(1979-),male,Master candidate,research direction:digital image processing. 展开更多
关键词 fingerprint matching b-spline interpolation knots detection PARAMETERIZATION boundary condition
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Numerical Solution of Obstacle Problems by B-Spline Functions
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作者 G.B Loghmani F Mahdifar S.R Alavizadeh 《American Journal of Computational Mathematics》 2011年第2期55-62,共8页
In this study, we use B-spline functions to solve the linear and nonlinear special systems of differential equations associated with the category of obstacle, unilateral, and contact problems. The problem can easily c... In this study, we use B-spline functions to solve the linear and nonlinear special systems of differential equations associated with the category of obstacle, unilateral, and contact problems. The problem can easily convert to an optimal control problem. Then a convergent approximate solution is constructed such that the exact boundary conditions are satisfied. The numerical examples and computational results illustrate and guarantee a higher accuracy for this technique. 展开更多
关键词 Least SQUARE Method UNIFORM b-splineS Boundary Value PROBLEMS OBSTACLE PROBLEMS
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The Analysis of Gauss Radial Basis Functions and Its Application in Locating Olivine on the Moon
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作者 SONG Shicang SONG Xiaoyuan SONG Shuhan 《应用数学》 北大核心 2026年第1期173-181,共9页
Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the m... Gauss radial basis functions(GRBF)are frequently employed in data fitting and machine learning.Their linear independence property can theoretically guarantee the avoidance of data redundancy.In this paper,one of the main contributions is proving this property using linear algebra instead of profound knowledge.This makes it easy to read and understand this fundamental fact.The proof of linear independence of a set of Gauss functions relies on the constructing method for one-dimensional space and on the deducing method for higher dimensions.Additionally,under the condition of preserving the same moments between the original function and interpolating function,both the interpolating existence and uniqueness are proven for GRBF in one-dimensional space.The final work demonstrates the application of the GRBF method to locate lunar olivine.By combining preprocessed data using GRBF with the removing envelope curve method,a program is created to find the position of lunar olivine based on spectrum data,and the numerical experiment shows that it is an effective scheme. 展开更多
关键词 Gauss function Radial basis function Machine learning Lunar olivine locating Data fitting
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Neuropeptide cholecystokinin:a key neuromodulator for hippocampal functions
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作者 Fengwen Huang Stephen Temitayo Bello 《Neural Regeneration Research》 SCIE CAS 2025年第7期1991-1992,共2页
Spatial memory is crucial for survival within external surroundings and wild environments.The hippocampus,a critical hub for spatial learning and memory formation,has received extensive investigations on how neuromodu... Spatial memory is crucial for survival within external surroundings and wild environments.The hippocampus,a critical hub for spatial learning and memory formation,has received extensive investigations on how neuromodulators shape its functions(Teixeira et al.,2018;Zhang et al.,2024).However,the landscape of neuromodulations in the hippocampal system remains poorly understood because most studies focus on classical monoamine neuromodulators,such as acetylcholine,serotonin,dopamine,and noradrenaline.The neuropeptides,comprising the most abundant neuromodulators in the central nervous system,play a pivotal role in neural information processing in the hippocampal system.Cholecystokinin(CCK),one of the most abundant neuropeptides,has been implicated in regulating various physiological and neurobiological statuses(Chen et al.,2019).CCK-A receptor(CCK-AR)and CCK-B receptors(CCK-BR)are two key receptors mediating the biological functions of CCK,both of which belong to class-A sevenfold transmembrane G protein-coupled receptors(Nishimura et al.,2015).CCK-AR preferentially reacts to sulfated CCK,whereas CCK-BR binds both CCK and gastrin with similar affinities(Ding et al.,2022).The expression patterns of CCK-AR and CCK-BR are distinct,implying that CCK has various functions in target regions.For instance,CCK-AR is widely expressed in the GI and brain subregions and is hence implicated in the control of digestive function and satiety regulation.Conversely,CCK-BR is abundantly and widely distributed in the central nervous system,which majorly regulates anxiety,learning,and memory(Ding et al.,2022).However,the roles of endogenous CCK and CCK receptors in regulating hippocampal function at electrophysiological and behavioral levels have received less attention. 展开更多
关键词 abundant functions MODULATOR
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Construction of Even-Variable 2-Output Almost Optimal Five-Valued Spectra Boolean Functions
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作者 SONG Chao-Fan JI Yan-Han SUN Yu-Juan 《密码学报(中英文)》 北大核心 2025年第3期714-728,共15页
Five-valued Boolean functions play an important role in the design of symmetric cryptography.While the design and properties of single-output almost optimal five-valued spectra Boolean functions have been extensively ... Five-valued Boolean functions play an important role in the design of symmetric cryptography.While the design and properties of single-output almost optimal five-valued spectra Boolean functions have been extensively studied over the past few decades,there has been limited research on the construction of almost optimal five-valued spectra vectorial Boolean functions.In this paper,we present a construction method for even-variable 2-output almost optimal five-valued spectra balanced Boolean functions,whose Walsh spectra values belong to the set{0,±2^(n/2),±2^(n/2+1)},at the same time,we discuss the existence of sufficient conditions in the construction.Additionally,this paper presents a novel construction method for balanced single-output Boolean functions with even variables featuring a special five-valued spectral structure,whose Walsh spectra values are constrained to the set{0,±2^(n/2),±3·2^(n/2)}.These functions provide new canonical examples for the study of Boolean function spectral theory. 展开更多
关键词 Boolean function Walsh transform semi-bent function five-valued function totally disjoint spectra functions
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High-quality control of receiver functions using a capsule neural network 被引量:1
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作者 Mona H.Hegazi Ahmad M.Faried Omar M.Saad 《Earthquake Science》 2025年第2期93-109,共17页
The Red Sea-Gulf of Suez-Cairo-Alexandria Clysmic-Trend in northern Egypt is the main earthquake zone in the country,with a moderate-to-high seismic hazard and a history of significant earthquakes caused by rifting an... The Red Sea-Gulf of Suez-Cairo-Alexandria Clysmic-Trend in northern Egypt is the main earthquake zone in the country,with a moderate-to-high seismic hazard and a history of significant earthquakes caused by rifting and active faulting.To improve our understanding of the tectonic and seismic processes in this area,more comprehensive imaging of the crustal structure is required.This can be achieved by increasing the number of receiver functions(RFs)recorded by the seismic stations in northern Egypt and the southeastern Mediterranean.Data handling and processing should also be automated to increase process efficiency.In this study,we developed a capsule neural network for automated selection of RFs.The model was trained on a dataset containing RFs(both selected and unselected)from five broadband stations in northern Egypt.Stations SLM,SIWA,KOT,NBNS,and NKL are located in the unstable shelf region of Egypt,where limited knowledge of the deep crustal structure is available.The proposed capsule neural network achieved an average precision of 80%on the test set.The automated selection of RFs using a capsule neural network has the potential to significantly improve the efficiency and accuracy of RF analysis,as demonstrated by the stacking test.This could lead to a better understanding of crustal structure and tectonic processes in northern Egypt and the southeastern Mediterranean. 展开更多
关键词 crustal structure receiver functions deep learning northern Egypt
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Consequences of Invariant Functions for the Riemann Hypothesis
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作者 Michael Mark Anthony 《Advances in Pure Mathematics》 2025年第1期36-72,共37页
This paper attempts to form a bridge between a sum of the divisors function and the gamma function, proposing a novel approach that could have significant implications for classical problems in number theory, specific... This paper attempts to form a bridge between a sum of the divisors function and the gamma function, proposing a novel approach that could have significant implications for classical problems in number theory, specifically the Robin inequality and the Riemann hypothesis. The exploration of using invariant properties of these functions to derive insights into twin primes and sequential primes is a potentially innovative concept that deserves careful consideration by the mathematical community. 展开更多
关键词 LambertW function Principal Branch Riemann Hypothesis ITERATIONS Robin Inequality Robin Integers INVARIANCE Gauss Gamma function Li-function Prime Counting function Sums of Divisors INVARIANCE PRIMES Twin Primes
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The biological functions of protein lactylation
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作者 CHEN Jia-Qi HE Yue-Jing +6 位作者 ZHENG Hui-Ling YUAN Yuan JIANG Zhi-Wen CHEN Jia-Jin ZHENG Xin-Yi LIU Xin-Guang SUN Xue-Rong 《生理学报》 北大核心 2025年第6期1035-1046,共12页
Lactylation is one of the post-translational modifications of proteins,a process in which lactyl residues bind to the lysine residues of proteins.This modification can alter the structure,stability,and function of pro... Lactylation is one of the post-translational modifications of proteins,a process in which lactyl residues bind to the lysine residues of proteins.This modification can alter the structure,stability,and function of proteins,which in turn regulates cellular metabolism,aging,and the onset of disease.This review classifies proteins with lactylation effects into histones and non-histone proteins and analyzes their functional roles when lactylation occurs.The in-depth exploration of lactylation is still in its infancy,and many aspects of its regulation,functional significance and therapeutic potential need to be further explored. 展开更多
关键词 lactylation post-translational modifications biological function HISTONES non-histone proteins
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Improved Bound of the Fourth Hankel Determinant for a Class of Analytic Functions with Bounded Turnings Involving Cardioid Domain
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作者 Dong GUO Huo TANG +1 位作者 Xi LUO Zongtao LI 《Journal of Mathematical Research with Applications》 2025年第1期39-55,共17页
In the paper,a class of functions with bounded turnings involving cardioid domain,are studied in the region of the unit disc.The bounds of|a_(5)|,|a_(6)|,|a_(7)|and the fourth Hankel determinant are obtained,which are... In the paper,a class of functions with bounded turnings involving cardioid domain,are studied in the region of the unit disc.The bounds of|a_(5)|,|a_(6)|,|a_(7)|and the fourth Hankel determinant are obtained,which are more accurate than those obtained by Srivastava. 展开更多
关键词 analytic functions starlike functions convex functions Schwarz function cardioid domain Hankel determinant
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Certain Subclasses of Bi-univalent Functions Associated with(u,v)-Chebyshev Polynomials
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作者 Timilehin Gideon Shaba Sibel Yalcin +1 位作者 Gangadharan Murugusundaramoorthy Maslina Darus 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第2期429-442,共14页
For the new subclass B of the bi-univalent functions constructed with the help of the(u,v)-Chebyshev polynomials of the second type,we get estimates for the first two initial coefficients and upper bounds of the Feket... For the new subclass B of the bi-univalent functions constructed with the help of the(u,v)-Chebyshev polynomials of the second type,we get estimates for the first two initial coefficients and upper bounds of the Fekete-Szeg o functional. 展开更多
关键词 univalent functions Fekete-Szeg˝o inequalities analytic functions starlike and convex functions of some order bi-univalent functions coefficient bounds SUBORDINATION
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REMARKS ON ASYMPTOTIC EXPANSIONS OF COMPOSITIONS WITH THE ELEMENTARY FUNCTIONS
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作者 LUO Xiao-Yu SHI Yong-Guo JIANG Zhi-Jie 《数学杂志》 2025年第2期131-139,共9页
In this paper,we study asymptotic power series of the composition f(x)=h(g(x)),where g(x)=∑_(n=0)^(∞)b_(n)x^(-n),b_(n)∈R,and h is a given elementary function.The asymptotic expansions have been obtained for the com... In this paper,we study asymptotic power series of the composition f(x)=h(g(x)),where g(x)=∑_(n=0)^(∞)b_(n)x^(-n),b_(n)∈R,and h is a given elementary function.The asymptotic expansions have been obtained for the composition with an exponential or logarithmic function.Using the re-cursive method,we present the asymptotic expansions for the composition with seven trigonometric functions,respectively.As an application,the asymptotic expansions of roots of some equations are given.Computational results show that our recursive formula is more efficient than the method of Lagrange's inverse theorem. 展开更多
关键词 asymptotic expansion asymptotic power series trigonometric function composite function
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The Investigation and Study of Hydrogen Atom in Spherical Cavity Using B-Spline Basis Functions: A Mathematical Approach
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作者 Alireza Heidari Foad Khademi Jahromi +1 位作者 Roozbeh Amiri Mohammadali Ghorbani 《Journal of Modern Physics》 2012年第4期334-339,共6页
The following article has been retracted due to the investigation of complaints received against it. The Editorial Board found that substantial portions of the text came from other published papers. The scientific com... The following article has been retracted due to the investigation of complaints received against it. The Editorial Board found that substantial portions of the text came from other published papers. The scientific community takes a very strong view on this matter, and the Health treats all unethical behavior such as plagiarism seriously. This paper published in Vol.3 No. 4, 334-339, 2012, has been removed from this site. 展开更多
关键词 Hydrogen ATOM Spherical Cavity b-spline Basis functions Quantum Systems Nanoscience VARIATIONAL Method Wave functions b-splines’ Properties
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Polymer Materials Synthesized in Living Cells for Regulating Biological Functions
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作者 Cheng-Fei Liu Yi-Fan Jin +2 位作者 Jia-Hui Ma Wei Tian Hua-Ping Xu 《Chinese Journal of Polymer Science》 2025年第8期1293-1310,共18页
Intracellular polymerization is an emerging field,showcasing high diversity and efficiency of chemistry.Motivated by the principles of natural biomolecular synthesis,polymerization within living cells is believed to b... Intracellular polymerization is an emerging field,showcasing high diversity and efficiency of chemistry.Motivated by the principles of natural biomolecular synthesis,polymerization within living cells is believed to be a powerful and versatile tool to modulate cell behavior.In this review,we summarized recent advances and future trends in the field of intracellular polymerization,specifically focusing on covalent and supramolecular polymerization.This discussion comprehensively covers the diverse chemical designs,reaction mechanisms,responsive features,and functional applications.Furthermore,we also clarified the connection between preliminary design of polymer synthesis and their subsequent biological applications.We hope this review will serve as an innovative platform for chemists and biologists to regulate biological functions in practical applications and clinical trials. 展开更多
关键词 Intracellular polymerization Covalent bonding Supramolecular interaction functional Polymer Materials Biological functions
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MONTEL'S CRITERION AND BLOCH-VALIRON'S THEOREM CONCERNING WANDERING FUNCTIONS
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作者 WANG Guang-sheng XU Yan 《数学杂志》 2025年第6期471-477,共7页
In this paper,we study normal families of meromorphic functions.By using the idea in[16],we obtain some normality criteria for families of meromorphic functions concerning the wandering multiple functions,which extend... In this paper,we study normal families of meromorphic functions.By using the idea in[16],we obtain some normality criteria for families of meromorphic functions concerning the wandering multiple functions,which extend and improve the well-known Montel's criterion,Bloch-Valiron's theorem,and the related results due to Carathéodory,and Grahl-Nevo et al.. 展开更多
关键词 Meromorphic function Normal family Montel's criterion Bloch-Valiron's the-orem wandering multiple function
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Environmental interpretation of spatial heterogeneity in the trade-offs and synergies of land use functions:A study based on the XGBoost-SHAP model
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作者 FENG Haoyuan ZHANG Xuebin +2 位作者 SHI Peiji SHI Jing WANG Ziyang 《Journal of Arid Land》 2025年第10期1378-1401,共24页
Accurately revealing the spatial heterogeneity in the trade-offs and synergies of land use functions(LUFs)and their driving factors is imperative for advancing sustainable land utilization and optimizing land use plan... Accurately revealing the spatial heterogeneity in the trade-offs and synergies of land use functions(LUFs)and their driving factors is imperative for advancing sustainable land utilization and optimizing land use planning.This is especially critical for ecologically vulnerable inland river basins in arid regions.However,existing methods struggle to effectively capture complex nonlinear interactions among environmental factors and their multifaceted relationships with trade-offs and synergies of LUFs,especially for the inland river basins in arid regions.Consequently,this study focused on the middle reaches of the Heihe River Basin(MHRB),an arid inland river basin in northwestern China.Using land use,socioeconomic,meteorological,and hydrological data from 2000 to 2020,we analyzed the spatiotemporal patterns of LUFs and their trade-off and synergy relationships from the perspective of production,living,ecological functions.Additionally,we employed an integrated Extreme Gradient Boosting(XGBoost)-SHapley Additive exPlanations(SHAP)framework to investigate the environmental factors influencing the spatial heterogeneity in the trade-offs and synergies of LUFs.Our findings reveal that from 2000 to 2020,the production,living,and ecological functions of land use within the MHRB exhibited an increasing trend,demonstrating a distinct spatial pattern of''high in the southwest and low in the northeast''.Significant spatial heterogeneity defined the trade-off and synergistic relationships,with trade-offs dominating human activity-intensive oasis areas,while synergies prevailed in other areas.During the study period,synergistic relationships between production and living functions and between production and ecological functions were relatively robust,whereas synergies in living-ecological functions remained weaker.Natural factors(digital elevation model(DEM),annual mean temperature,Normalized Difference Vegetation Index(NDVI),and annual precipitation)emerged as the primary factors driving the trade-offs and synergies of LUFs,followed by socioeconomic factors(population density,Gross Domestic Product(GDP),and land use intensity),while distance factors(distance to water bodies,distance to residential areas,and distance to roads)exerted minimal influence.Notably,the interactions among NDVI,annual mean temperature,DEM,and land use intensity exerted the most substantial impacts on the relationships among LUFs.This study provides novel perspectives and methodologies for unraveling the mechanisms underlying the spatial heterogeneity in the trade-offs and synergies of LUFs,offering scientific insights to inform regional land use planning and sustainable natural resource management in inland river basins in arid regions. 展开更多
关键词 production function living function ecological function trade-offs and synergies Extreme Gradient Boosting(XGBoost) SHapley Additive exPlanations(SHAP) Heihe River Basin
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Normality and Shared Functions Wandering on the Sphere
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作者 Guangsheng WANG Fei LI Yan XU 《Journal of Mathematical Research with Applications》 2025年第3期329-336,共8页
In this paper,we obtain a normality criterion for families of meromorphic functions concerning‘wandering’shared functions,which generalizes and improves Montel’s criterion and the related results due to Schwick,Xu-... In this paper,we obtain a normality criterion for families of meromorphic functions concerning‘wandering’shared functions,which generalizes and improves Montel’s criterion and the related results due to Schwick,Xu-Fang,Xu-Qiu,and Grahl-Nevo.Also,a normality relationship between two families is given. 展开更多
关键词 meromorphic function normal family wandering shared function Montel’s criterion
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On α-Bloch Functions in Several Complex Variables
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作者 ZHU Ting YANG Liu 《Chinese Quarterly Journal of Mathematics》 2025年第1期93-102,共10页
In this paper,we establish characterizations of α-Bloch functions and little α-Bloch functions on the unit ball as well as the unit polydisk of C^(m),which generalize and improve results of Aulaskari-Lappan,Minda,Au... In this paper,we establish characterizations of α-Bloch functions and little α-Bloch functions on the unit ball as well as the unit polydisk of C^(m),which generalize and improve results of Aulaskari-Lappan,Minda,Aulaskari-Wulan,and Wu.Some examples are also given to complement our theory. 展开更多
关键词 α-Bloch function Littleα-Bloch function Several complex variables Partial derivative
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Two Dimensional Tensor Product B-Spline Wavelet Scaling Functions for the Solution of Two-Dimensional Unsteady Diffusion Equations
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作者 XIONG Lei LI haijiao ZHANG Lewen 《Journal of Ocean University of China》 SCIE CAS 2008年第3期258-262,共5页
The fourth-order B spline wavelet scaling functions are used to solve the two-dimensional unsteady diffusion equation. The calculations from a case history indicate that the method provides high accuracy and the compu... The fourth-order B spline wavelet scaling functions are used to solve the two-dimensional unsteady diffusion equation. The calculations from a case history indicate that the method provides high accuracy and the computational efficiency is enhanced due to the small matrix derived from this method.The respective features of 3-spline wavelet scaling functions,4-spline wavelet scaling functions and quasi-wavelet used to solve the two-dimensional unsteady diffusion equation are compared. The proposed method has potential applications in many fields including marine science. 展开更多
关键词 wavelet analysis b-spline wavelet tensor product RESOLUTION diffusion equations
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Robust control barrier functions based on active disturbance rejection control for adaptive cruise control
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作者 Jaime Arcos-Legarda Andres Hoyos Hernán García Arias 《Control Theory and Technology》 2025年第3期454-463,共10页
The objective of this paper is to present a robust safety-critical control system based on the active disturbance rejection control approach, designed to guarantee safety even in the presence of model inaccuracies, un... The objective of this paper is to present a robust safety-critical control system based on the active disturbance rejection control approach, designed to guarantee safety even in the presence of model inaccuracies, unknown dynamics, and external disturbances. The proposed method combines control barrier functions and control Lyapunov functions with a nonlinear extended state observer to produce a robust and safe control strategy for dynamic systems subject to uncertainties and disturbances. This control strategy employs an optimization-based control, supported by the disturbance estimation from a nonlinear extended state observer. Using a quadratic programming algorithm, the controller computes an optimal, stable, and safe control action at each sampling instant. The effectiveness of the proposed approach is demonstrated through numerical simulations of a safety-critical interconnected adaptive cruise control system. 展开更多
关键词 Control barrier functions Active disturbance rejection control Extended state observer Control Lyapunov function Optimization-based control Quadratic programming
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