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ON NEW STRATEGIES TO CONTROL THE ACCURACY OF WENO ALGORITHM CLOSE TO DISCONTINUITIES Ⅱ:CELL AVERAGES AND MULTIRESOLUTION

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Journal of Computational Mathematics 2020年第4期38卷 661-682页

作者： Sergio Amat Juan Ruiz Chi-Wang Shu department of Applied Mathematics and Statistics Universidad Politecnica de CartagenaSpain Division of Applied Mathematics Brown UniversityUSA

This paper is the second part of the article and is devoted to the construction and analysis of new non-linear optimal weights for WENO interpolation capable of rising the order of accuracy close to discontinuities for data discretized in the cell averages.Thus,now we are interested in analyze the capabilities of the new algorithm when working with functions belonging to the subspace L1\L2 and that,consequently,are piecewise smooth and can present jump discontinuities.The new non-linear optimal weights are redesigned in a way that leads to optimal theoretical accuracy close to the discontinuities and at smooth zones.We will present the new algorithm for the approximation case and we will analyze its accuracy.Then we will explain how to use the new algorithm in multiresolution applications for univariate and bivariate functions.The numerical results confirm the theoretical proofs presented.

关键词： WENO Cell averages New optimal weights Multiresolution schemes Im-proved adaption to discontinuities Signal processing

Heat Transfer Enhancement in a Parabolic Trough Solar Receiver using Longitudinal Fins and Nanofluids

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Journal of Thermal Science 2016年第5期25卷 410-417页

作者： Amina Benabderrahmane Miloud Aminallah Samir Laouedj Abdelylah Benazza J.P.Solano Laboratory of Reactive Systems and Materials DjiUali Liabes UniversitySidi Bel AbbesAlgeria Ingenieria Termica y de Fluidos Univcrsidad Politecnica de CartagenaCartagenaSpain

In this paper,we present a three dimensional numerical investigation of heat transfer in a parabolic trough collector receiver with longitudinal fins using different kinds of nanofluid,with an operational temperature of 573 K and nanoparticle concentration of 1% in volume.The outer surface of the absorber receives a non-uniform heat flux,which is obtained by using the Monte Carlo ray tracing technique.The numerical results are contrasted with empirical results available in the open literature.A significant improvement of heat transfer is derived when the Reynolds number varies in the range 2.57×104≤ Re≤ 2.57×105,the tube-side Nusselt number increases from 1.3 to 1.8 times,also the metallic nanoparticles improve heat transfer greatly than other nanoparticles,combining both mechanisms provides better heat transfer and higher thermo-hydraulic performance.

关键词：强化传热纵向翅片接收器抛物太阳能金属纳米粒子槽式纳米流体

A Toughness Condition for Fractional(k, m)-deleted Graphs Revisited

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Acta Mathematica Sinica,English Series 2019年第7期35卷 1227-1237页

作者： Wei GAO Juan L.G.GUIRAO Yao Jun CHEN department of Mathematics Nanjing University Nanjing 210093 P. R. China School of Information Science and Technology Yunnan Normal University Kunming 650500 P. R. China departamento de Matematica Aplicada y Estadistica. universidad politecnica de cartagena Hospital de Marina 30203-Cartagena Region de Murcia Spain

In computer networks, toughness is an important parameter which is used to measure the vulnerability of the network. Zhou et al. obtains a toughness condition for a graph to be fractional(κ, m)-deleted and presents an example to show the sharpness of the toughness bound. In this paper, we remark that the previous example does not work and inspired by this fact, we present a new toughness condition for fractional(κ, m)-deleted graphs improving the existing one. Finally, we state an open problem.

关键词： Graph fractional factor fractional (κ, m)-deleted graph toughness

The Extension degree Conditions for Fractional Factor

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Acta Mathematica Sinica,English Series 2020年第3期36卷 305-317页

作者： Wei GAO Wei Fan WANG Juan L.G.GUIRAO School of Information Science and Technology Yunnan Normal UniversityKunming 650500P.R.China department of Mathematics Zhejiang Normal UniversityJinhua 321004P.R.C hina departamento de Matematica Aplicada y Estadistica.universidad politecnica de cartagena Hospital de Marina30203-CartagenaRegion de MurciaSpain

In Gao’s previous work, the authors determined several degree conditions of a graph which admits fractional factor in particular settings. It was revealed that these degree conditions are tight if b = f(x) = g(x) = a for all vertices x in G. In this paper, we continue to discuss these degree conditions for admitting fractional factor in the setting that several vertices and edges are removed and there is a difference Δ between g(x) and f(x) for every vertex x in G. These obtained new degree conditions reformulate Gao’s previous conclusions, and show how Δ acts in the results. Furthermore,counterexamples are structured to reveal the sharpness of degree conditions in the setting f(x) =g(x) + Δ.

关键词： Fractional factor degree condition independent set

Methodology for Obtaining Electricity-Price Patterns in Customer Response Programs

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Journal of Energy and Power Engineering 2011年第11期5卷 1087-1095页

作者： A. Gabaldon A. Guillamon M.C. Ruiz S. Valero M. Ortiz C. Senabre C. Alvarez department of Electrical Engineering Universidad Politeenica de Cartagena Murcia 30202 Spain department of Applied Mathematics and Statistics Universidad Politecnica de Cartagena Murcia 30202 Spain department of Mechanical and Energy Engineering Universidad Miguel Hernandez Alicante 03202 Spain Institute of Energy Engineering Universidad Politecnica de Valencia Valencia 46022 Spain

The main objective of electricity regulators when establishing electricity markets is to decrease the cost of electricity through competition. However, this scenario cannot be achieved without a full participation of the electricity demand by reacting against electricity prices. The aim of this research is to develop tools for helping customers and aggregators to join price and demand response programs, while helping them to hedge against the risk of short-term price volatility. In this way, the capacity of and hybrid methodology (Self-Organizing Maps and Statistical Ward’s Linkage) to classify high electricity market prices is analysed. Besides, with the help of Non-Parametric Estimation, some price-patterns were found in the abovementioned clusters. The contained knowledge within these patterns supplies customer market-based information on which to base its energy use decisions. The interest for this participation of customers in markets is growing in developed countries to obtain a higher elasticity in demand. Results show the capability of this approach to improve data management and select coherent policies to accomplish cleared demand offers amongst different price scenarios in a more flexible way.

关键词：电力价格客户程序电力市场电力监管机构自组织映射非参数估计电力成本

Computing Recomposition of Maps with a New Sampling Asymptotic Formula

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Open Journal of Discrete Mathematics 2011年第2期1卷 43-49页

作者： Almudena Antuna Juan L.G.Guirao Miguel A.Lopez departamento de Analisis Economico y Finanzas Universidad de Castilla-La ManchaCuenca(Castilla-La Mancha)Spain departamento de Matematica Aplicada y Estadstica Universidad Politecnica de CartagenaCartagena(Region de Murcia)Spain departamento de Matematicas Universidad de Castilla-La ManchaCuenca(Castilla-La Mancha)Spain

The aim of the present paper is to state an asymptotic property Ρ of Shannon’s sampling theorem type, based on normalized cardinal sines, and keeping constant the sampling frequency of a not necessarilly band- limited signal. It generalizes in the limit the results stated by Marvasti et al. [7] and Agud et al. [1]. We show that Ρ is fulfilled for any constant signal working for every given sampling frequency. Moreover, we conjecture that Gaussian maps of the form e-Λt2 ,Λ∈R+, hold Ρ. We support this conjecture by proving the equality given by for the three first coefficients of the power series representation of e-Λt2 .

关键词： Band-Limited Signal Shannon's Sampling Theorem Approximation Theory

Green HACCP:Food Safety and Environment

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Journal of Food Science and Engineering 2019年第2期9卷 68-71页

作者： Mohamed Zarid department of Agricultural&Food Engineering Regional Campus of International Excellence“Campus Mare Nostrum”(CMN)Universidad Politecnica de Cartagena(UPCT)Paseo Alfonso XIII48ETSIAE-30203 CartagenaMurciaSpain

Green HACCP(hazard analysis and critical control point)is a new control method developed by combining food safety controls and good practices for environmental protection,in order to have a safe production that respects the environment.Indeed,some of production practices,such as the use of large amount of water,cleaning/disinfection products and other practices used to have safe foodstuffs,could affect the environment and the profitability in several agri-food process.The goal of Green HACCP is to apply a sustainable rationalization of the good hygienic and environmental practices.

关键词： Quality food safety environment parallel control system agri-food industries

Insecticide Resistance in Field Populations of Bemisia tabaci In Southeastern Spain

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Insecticide Resistance in Field Populations of Bemisia tabac...