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Analysis and management strategies for the low voltage problems of rural power grid based on the distribution network flow calculation method 被引量:2
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作者 陈曦 何俊宏 HE Yu-cheng 《Journal of Chongqing University》 CAS 2015年第4期134-140,共7页
For a long time, because of the lack of investment capital and enough attentions, the overall constructions of rural power grid were far behind than the urban power grid in Chongqing Jiangbei Power Company. The low vo... For a long time, because of the lack of investment capital and enough attentions, the overall constructions of rural power grid were far behind than the urban power grid in Chongqing Jiangbei Power Company. The low voltage problems were highlighted in the rural power grid due to the characteristics of rural power grid. Using the distribution network flow calculation method, we evaluated the low voltage problems of the rural power grid which belongs to Chongqing Jiangbei Power Company. In addition, we collected the data of distribution transformers in electricity consumption peak period. Some practical management strategies were proposed by the analysis and evaluation of potential and appeared low voltage problems. 展开更多
关键词 RURAL power GRID flow CALCULATION method low VOLTAGE PROBLEM management strategy
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Thermal Effects and RF Power Handling of DC~5GHz MEMS Switch 被引量:1
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作者 吕苗 赵正平 +3 位作者 娄建忠 顾洪明 胡小东 李倩 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第7期749-755,共7页
A DC to 5GHz series MEMS switch is designed and fabricated for wireless communication applications,and thermal effect and power handling of the series switch are discussed.The switch is made on glass substrate,and gol... A DC to 5GHz series MEMS switch is designed and fabricated for wireless communication applications,and thermal effect and power handling of the series switch are discussed.The switch is made on glass substrate,and gold platinum contact is used to get a stable and little insert loss.From DC to 5GHz,0 6dB insertion loss,30dB isolation,and 30μs delay are demonstrated.Thermal effect of the switch is tested in 85℃ and -55℃ atmosphere separately.From DC to 4GHz,the insert loss of the switch increases 0 2dB in 85℃ and 0 4dB in -55℃,while the isolation holds the same value as that in room temperature.To measure the power handling capability of the switch,we applied a continuous RF power increasing from 10dBm to 35 1dBm with the step of 1 0dBm across the switch at 4GHz.The switch keeps working and shows a decrease of the insert loss for 0 1~0 6dB.The maximum continuous power handling (35 1dBm,about 3 24W) is higer than the reported value of shunt switch (about 420mW),which implies series switches have much better power handling capability. 展开更多
关键词 RF MEMS switches thermal effects power handling capability
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On the Coalitional Rationality and the Inverse Problem for Shapley Value and the Semivalues 被引量:1
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作者 Irinel Dragan 《Applied Mathematics》 2017年第11期1590-1601,共12页
In cooperative game theory, a central problem is to allocate fairly the win of the grand coalition to the players who agreed to cooperate and form the grand coalition. Such allocations are obtained by means of values,... In cooperative game theory, a central problem is to allocate fairly the win of the grand coalition to the players who agreed to cooperate and form the grand coalition. Such allocations are obtained by means of values, having some fairness properties, expressed in most cases by groups of axioms. In an earlier work, we solved what we called the Inverse Problem for Semivalues, in which the main result was offering an explicit formula providing the set of all games with an a priori given Semivalue, associated with a given weight vector. However, in this set there is an infinite set of games for which the Semivalues are not coalitional rational, perhaps not efficient, so that these are not fair practical solutions of the above fundamental problem. Among the Semivalues, coalitional rational solutions for the Shapley Value and the Banzhaf Value have been given in two more recent works. In the present paper, based upon a general potential basis, relative to Semivalues, for a given game and a given Semivalue, we solve the connected problem: in the Inverse Set, find out a game with the same Semivalue, which is also coalitional rational. Several examples will illustrate the corresponding numerical technique. 展开更多
关键词 Shapley VALUE Banzhaf VALUE Semivalues INVERSE Problem POWER Game POWER Core Coalitional RATIONALITY
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Model and Algorithm for the Optimal Controlled Partitioning of Power Systems 被引量:15
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作者 LIN Jikeng LI Shengwen +4 位作者 WU Peng WANG Xudong SHAO Guanghui XU Xingwei MA Xin 《中国电机工程学报》 EI CSCD 北大核心 2012年第13期I0012-I0012,195,共1页
解列是电力系统在故障时结构完整性得不到保证的情况下分裂为2个或多个孤立稳定运行子系统的过程或操作。及时恰当的主动解列操作将能有效地避免因保护连锁动作使得电力系统被动解列而崩溃所造成的巨额经济损失。结合图论中的相关概念... 解列是电力系统在故障时结构完整性得不到保证的情况下分裂为2个或多个孤立稳定运行子系统的过程或操作。及时恰当的主动解列操作将能有效地避免因保护连锁动作使得电力系统被动解列而崩溃所造成的巨额经济损失。结合图论中的相关概念和输电网最优解列的物理过程,建立电力系统最优主动解列断面选择问题的完整数学模型,并基于含连通图约束的背包问题(connected graph constrained knapsack problem,CGKP)及其求解算法提出“搜索+调整”的2阶段求解方法。为降低问题的复杂性,将完整数学模型分解成图的最优平衡分割问题和基于优化潮流的调节问题,并分2个阶段分别求解。其中,图的最优平衡分割问题又被分解成多个CGKP,利用基于含CGKP的图分割方法进行求解。所提出的主动解列策略具有较强理论基础,计算复杂度低,算例的计算结果证明了该模型及算法的正确性和有效性。 展开更多
关键词 系统最优控制 电力输送 分区 大面积停电 算法 模型 联网系统 间接损失
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Combining the People Power and the Process Power to Achieve Six Sigma Process Capability——A Case Study
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作者 G Srinivasan N Srinivasa Gupta 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期251-,共1页
Achieving Six-Sigma process capability starts with l istening to the Voice of the Customers, and it becomes a reality by combining th e People Power and the Process Power of the organisation. This paper presents a Six... Achieving Six-Sigma process capability starts with l istening to the Voice of the Customers, and it becomes a reality by combining th e People Power and the Process Power of the organisation. This paper presents a Six-Sigma implementation case study carried out in a magnet manufacturing compa ny, which produces bearing magnets to be used in energy meters. If the thickness of the produced bearing magnets is between 2.35 mm and 2.50 mm, they will be ac cepted by the customers. All the time the company could not produce the bearing magnets within the specified thickness range, as their process distribution was flat with 2.20 mm as lower control limit and 2.60 mm as upper control limit. This resulted in a huge loss in the form of non-conformities, loss of time and goodwill. The process capability of the company then was around 0.40. Organisat ion restructuring was carried out to reap the benefit of the People Power of the organisation. Statistically designed experiments (Taguchi Method based Design o f Experiments), Online quality control tools (Statistical Process Control To ols) were effectively used to complete the DMAIC (Define, Measure, Analyse, Impr ove and Control) cycle to reap the benefit of the Process Power of the organisat ion. Presently the company enjoys a process capability of 1.75, a way towards Si x-Sigma Process Capability. 展开更多
关键词 six-sigma process capability people power proc ess power statistically designed experiments online quality control tools
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Non-Linear Synthesis Problems for Plane Radiating Systems According to the Prescribed Power Directivity Pattern
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作者 Mykhaylo Andriychuk Petro Savenko Myroslava Tkach 《Open Journal of Antennas and Propagation》 2013年第2期23-34,共12页
A variational formulation of the synthesis problem for plane radiating systems according to the prescribed power directivity pattern (DP) is considered. The function representing the mean-square deviation of the presc... A variational formulation of the synthesis problem for plane radiating systems according to the prescribed power directivity pattern (DP) is considered. The function representing the mean-square deviation of the prescribed and synthesized power DPs and containing the additional term with squared norm of the current or field in the antenna aperture is considered as the criterion of optimization. Freedom to choose the phase DP is used to improve the proximity of the prescribed and synthesized DPs. In such formulation, the classes of non-linear problems, for which the non-uniqueness of solutions, their branching and bifurcation are characteristic, arise. The properties of solutions depend on the electric size of radiating system and prescribed power DP. From a practical point of view, the existence of different solutions creating the same or similar DPs, gives the opportunity to choose the solution that has a simpler implementation. The synthesis problems for plane radiating systems and plane arrays are considered. 展开更多
关键词 POWER Radiation Pattern SYNtheSIS Problem NON-LINEAR Equation BIFURCATION of Solutions Numerical Modeling
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Problems of Hazardous Waste Storage Facilities in Coal-fired Power Plants and Countermeasures
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作者 Wenqi YUE 《Meteorological and Environmental Research》 CAS 2023年第2期57-60,65,共5页
The hazardous waste produced by coal-fired power plants are large in quantity and variety. It is important for ecological environment protection to properly store hazardous waste in coal-fired power plants. The enviro... The hazardous waste produced by coal-fired power plants are large in quantity and variety. It is important for ecological environment protection to properly store hazardous waste in coal-fired power plants. The environmental management of hazardous waste in coal-fired power plants started late, and there are many problems in the construction and management of their storage facilities. In this paper, taking eight typical coal-fired power plants as examples, the present problems of hazardous waste storage facilities in coal-fired power plants are analyzed, and corresponding countermeasures are put forward to solve the main common problems. 展开更多
关键词 Coal-fired power plants Hazardous waste storage Types of problems COUNTERMEASURES
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Advances in the Application of Molecular Diagnostic Techniques to Brucellosis
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作者 Haiwen Liu Hai Jiang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第7期790-794,共5页
Brucellosis is a zoonotic infectious and allergic disease caused by Brucella bacteria.Brucellosis occurs worldwide and has had a huge economic impact on the livestock industry in many countries and regions.It has beco... Brucellosis is a zoonotic infectious and allergic disease caused by Brucella bacteria.Brucellosis occurs worldwide and has had a huge economic impact on the livestock industry in many countries and regions.It has become a major public health problem.Brucella is an endoparasitic,non-motile Gram-negative bacterium capable of surviving within a diverse range of domestic animal hosts. 展开更多
关键词 PROBLEM diverse capable
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Equipment delivery and quality problems affectingcompletion of 1997 Power Construction Plan
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《Electricity》 1998年第2期43-44,共2页
关键词 Equipment delivery and quality problems affecting completion of 1997 Power Construction Plan
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Determination of the Orthotropic Material Behavior of Stator Bars and of the Material Characteristics of the Space Brackets
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作者 Bemd Schlegl Florian Schonleitner +2 位作者 Andreas Mare Fritz Neumayer Franz Heitmeir 《Journal of Energy and Power Engineering》 2013年第7期1352-1361,共10页
The end windings of generators are excited to vibrations due to electromagnetic forces which can cause severe damage (especially in case of resonance) and noise. To avoid this, it is important to predict the natural... The end windings of generators are excited to vibrations due to electromagnetic forces which can cause severe damage (especially in case of resonance) and noise. To avoid this, it is important to predict the natural frequencies and modes of the end windings with finite elements during the design process. Hence, a material model of the complete stator bar is necessary. This paper shows the development of such a material model. The composite structure of a stator bar is quite complex and makes it impossible to provide a quick calculation of the eigenvalues. That is the reason for using a suitable, homogeneously, geometry based solid model. Special attention was paid to the experimental determination of the material characteristics of the orthotropic composite space brackets. The numerical results have been evaluated against measurements. Eigenvalues, Young's modulus, and shear modulus have been experimentally investigated. 展开更多
关键词 Electrical machines end windings finite element method generators hydro generator power generation stator bars vibration problems.
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RESTUDY OF THEORIES FOR ELASTIC SOLIDS WITH MICROSTRUCTURE 被引量:1
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作者 DAI Tian- min(戴天民) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第8期867-874,共8页
The dynamical theories of elastic solids with microstructure are restudied and the reason why so many notations have been introduced for derivation of basic equations for such theories is given. In view of the existin... The dynamical theories of elastic solids with microstructure are restudied and the reason why so many notations have been introduced for derivation of basic equations for such theories is given. In view of the existing problems in those theories the rather general principle of power and energy rate is postulated and the equations of motion, the balance equations of energy rate and energy and the boundary conditions for local and nonlocal theories are naturally derived with help of that principle and the generalized Piola's theorem. These basic equations and the boundary conditions together with the initial conditions may be. used to solve the mixed problems of the dynamical theory of elastic solids with microstructure. 展开更多
关键词 elastic solid MICROSTRUCTURE principle of power and energy rate mixed problem
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Mathematical Reasoning of Treatment Principle Based on the Stable Logic Analysis Model of Complex Systems 被引量:2
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作者 Yingshan Zhang 《Intelligent Control and Automation》 2012年第1期1-15,共15页
The article reviews the stable logic analysis model of complex systems or steady multilateral systems with two non-compatibility relations. Energy concept in Physics is introduced to the multilateral systems and used ... The article reviews the stable logic analysis model of complex systems or steady multilateral systems with two non-compatibility relations. Energy concept in Physics is introduced to the multilateral systems and used to deal with the multilateral system diseases. By using mathematical reasoning, it is demonstrated that the treatment principle: “Virtual disease is to fill his mother but real disease is to rush down his son” and “Strong inhibition of the same time, support the weak” which due to the “Yin Yang Wu Xing” Theory in Traditional Chinese Medicine (TCM). 展开更多
关键词 STEADY Multilateral Systems Opposite RELATIONS CAPABILITY of INTERVENTION Reaction CAPABILITY of SELF-PROTECTION Side Effects Medical and Drug Resistance Problem
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THE MIXED BOUNDARY-VALUE PROBLEM FOR NON-LOCAL ASYMMETRIC ELASTICITY 被引量:1
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作者 戴天民 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第1期29-34,共6页
In this paper, the equations of motion and all boundary conditions as well as the energy equation for non_local asymmetric elasticity are derived together from the complete principles of virtual work and virtual power... In this paper, the equations of motion and all boundary conditions as well as the energy equation for non_local asymmetric elasticity are derived together from the complete principles of virtual work and virtual power as well as the generalized Piola theorem. Adding the boundary conditions presented here to the results by Gao Jian and Dai Tianmin,the mixed boundary_value problem of the non_local asymmetric linear elasticity are formulated. 展开更多
关键词 non_local asymmetric elasticity principles of virtual work and power mixed boundary_value problem
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A Series Solution Approach to the Circular Restricted Gravitational Three-Body Dynamical Problem 被引量:1
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作者 Maha Hamed Alghamdi Aisha Abdu Alshaery 《Journal of Applied Mathematics and Physics》 2020年第12期2703-2712,共10页
The present manuscript examines the circular restricted gravitational three-body problem (CRGTBP) by the introduction of a new approach through the power series method. In addition, certain computational algorithms wi... The present manuscript examines the circular restricted gravitational three-body problem (CRGTBP) by the introduction of a new approach through the power series method. In addition, certain computational algorithms with the aid of Mathematica software are specifically designed for the problem. The algorithms or rather mathematical modules are established to determine the velocity and position of the third body’s motion. In fact, the modules led to accurate results and thus proved the new approach to be efficient. 展开更多
关键词 n-Body problems Restricted Gravitational problems Power Series Method Series Solution Approach
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Key Problems of Cold Power Spinning of Ti-15-3 Alloy 被引量:1
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作者 Debin SHAN Yan LU and Ping LI School of Materials Science and Engineering, Harbin institute of Thchnology, Harbin 150001, China Yi XU Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第1期125-126,共2页
The key problems of cold power spinning of Ti-15-3 alloy are studied. Reasonable billet preparation methods are presented to improve crystal structure and avoid crack of billet. Influences of original wall thickness,... The key problems of cold power spinning of Ti-15-3 alloy are studied. Reasonable billet preparation methods are presented to improve crystal structure and avoid crack of billet. Influences of original wall thickness, reduction rate and feed rate on expanding in diameter are analyzed and some methods to prevent expanding in diameter are given. 展开更多
关键词 TI Key problems of Cold Power Spinning of Ti-15-3 Alloy
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Radio Network Planning and Optimization for 5G Telecommunication System Based on Physical Constraints 被引量:1
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作者 Hla Myo Tun 《Journal of Computer Science Research》 2021年第1期1-15,共15页
The paper mainly focuses on the network planning and optimization problem in the 5G telecommunication system based on the numerical investigation.There have been two portions of this work,such as network planning for ... The paper mainly focuses on the network planning and optimization problem in the 5G telecommunication system based on the numerical investigation.There have been two portions of this work,such as network planning for efficient network models and optimization of power allocation in the 5G network.The radio network planning process has been completed based on a specific area.The data rate requirement can be solved by allowing the densification of the system by deploying small cells.The radio network planning scheme is the indispensable platform in arranging a wireless network that encounters convinced coverage method,capacity,and Quality of Service necessities.In this study,the eighty micro base stations and two-hundred mobile stations are deployed in the-15km×15km wide selected area in the Yangon downtown area.The optimization processes were also analyzed based on the source and destination nodes in the 5G network.The base stations’location is minimized and optimized in a selected geographical area with the linear programming technique and analyzed in this study. 展开更多
关键词 Network planning design Mathematical optimization 5G telecommunication system Numerical analysis Power allocation problem
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SOLUTION OF THE RAYLEIGH PROBLEM FOR A POWER-LAW NON-NEWTONIAN CONDUCTING FLUID VIA GROUP METHOD
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作者 Mina B.Abd-el-Malek Nagwa A.Badran Hossam S.Hassan 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2002年第6期639-646,共8页
An investigation is made of the magnetic Rayleigh problem where a semi_infinite plate is given an impulsive motion and thereafter moves with constant velocity in a non_Newtonian power law fluid of infinite extent. The... An investigation is made of the magnetic Rayleigh problem where a semi_infinite plate is given an impulsive motion and thereafter moves with constant velocity in a non_Newtonian power law fluid of infinite extent. The solution of this highly non_linear problem is obtained by means of the transformation group theoretic approach. The one_parameter group transformation reduces the number of independent variables by one and the governing partial differential equation with the boundary conditions reduce to an ordinary differential equation with the appropriate boundary conditions. Effect of the some parameters on the velocity u(y,t) has been studied and the results are plotted. 展开更多
关键词 Rayleigh problem group method non_linearity conducting fluid non_Newtonian power law fluid
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WEAK REGULARIZATION FOR A CLASS OF ILL-POSED CAUCHY PROBLEMS
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作者 黄永忠 郑权 《Acta Mathematica Scientia》 SCIE CSCD 2006年第3期483-490,共8页
This article is concerned with the ill-posed Cauchy problem associated with a densely defined linear operator A in a Banach space. A family of weak regularizing operators is introduced. If the spectrum of A is contain... This article is concerned with the ill-posed Cauchy problem associated with a densely defined linear operator A in a Banach space. A family of weak regularizing operators is introduced. If the spectrum of A is contained in a sector of right-half complex plane and its resolvent is polynomially bounded, the weak regularization for such ill-posed Cauchy problem can be shown by using the quasi-reversibilky method and regularized semigroups. Finally, an example is given. 展开更多
关键词 Ill-posed Cauchy problem QUASI-REVERSIBILITY family of weakly regularizing operators fractional power regularized semigroup
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Approximate analytical solutions and approximate value of skin friction coeffcient for boundary layer of power law fluids
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作者 苏晓红 郑连存 蒋锋 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第9期1215-1220,共6页
This paper presents a theoretical analysis for laminar boundary layer flow in a power law non-Newtonian fluids. The Adomian analytical decomposition technique is presented and an approximate analytical solution is obt... This paper presents a theoretical analysis for laminar boundary layer flow in a power law non-Newtonian fluids. The Adomian analytical decomposition technique is presented and an approximate analytical solution is obtained. The approximate analytical solution can be expressed in terms of a rapid convergent power series with easily computable terms. Reliability and efficiency of the approximate solution are verified by comparing with numerical solutions in the literature. Moreover, the approximate solution can be successfully applied to provide values for the skin friction coefficient of the laminar boundary layer flow in power law non-Newtonian fluids. 展开更多
关键词 power law fluid nonlinear boundary value problem Adomian decomposi-tion
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Interpolation by Bivariate Polynomials Based on Multivariate F-truncated Powers
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作者 Yuan Xue-mei 《Communications in Mathematical Research》 CSCD 2014年第4期379-382,共4页
The solvability of the interpolation by bivariate polynomials based on multivariate F-truncated powers is considered in this short note. It unifies the pointwise Lagrange interpolation by bivariate polynomials and the... The solvability of the interpolation by bivariate polynomials based on multivariate F-truncated powers is considered in this short note. It unifies the pointwise Lagrange interpolation by bivariate polynomials and the interpolation by bivariate polynomials based on linear integrals over segments in some sense. 展开更多
关键词 multivariate F-truncated power point-wise Lagrange interpolation solvability of an interpolation problem
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