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Acta Mathematica Scientia 2011年第6期31卷 2122-2130页

作者： Bashir Ahmad juan j. nieto Ahmed Alsaedi Department of Mathematics Faculty of ScienceKing Abdulaziz University Departamento de Anlisis Matemtico Facultad de MatemticasUniversidad de Santiago de Compostela

In this paper, we study a boundary value problem of nonlinear fractional dif- ferential equations of order q （1 〈 q 〈 2） with non-separated integral boundary conditions. Some new existence and uniqueness results are obtained by using some standard fixed point theorems and Leray-Schauder degree theory. Some illustrative examples are also presented. We extend previous results even in the integer case q = 2.

关键词： fractional differential equations non-separated integral boundary conditions contraction principle Krasnoselskii's fixed point theorem LeraySchauder degree

The number of alignments between two DNA sequences

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International j.urnal of Biomathematics 2016年第4期9卷 75-80页

作者： Helena Andrade juan j. nieto Angela Torres Departamento de Andlisis Matemdtico Facultad de Matemdticas Universidad de Santiago de Compostela Spain Department of Mathematics Faculty of ScienceKing Abdulaziz University Jeddah 21589 Saudi Arabia Departamento de Psiquiatrla Radiologla y Salud Publica Facultad de Medicina Universidad de Santiago de Compostela Spain

We consider two DNA sequences and compare both sequences. One of the crucial issues in bioinformatics is to measure the similarity of two DNA sequences. To this purpose one has to consider different alignments between both sequences. The number of alignments grows very rapidly with the length of the sequences. In this paper we give exact, explicit and computable formulas for the number of different possible alignments and for some classes of reduced alignments. We provide a new insight into the theory of DNA sequence alignment.

关键词： DNA sequence alignment difference equation.

Cosmological Model in Four Time and Four Space Dimensions

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j.urnal of Applied Mathematics and Physics 2024年第3期12卷 829-840页

作者： juan Antonio nieto Facultad de Ciencias Físico-Matemáticas de la Universidad Autónoma de Sinaloa Culiacán Sinaloa México

We develop a cosmological model in a physical background scenario of four time and four space dimensions ((4+4)-dimensions or (4+4)-universe). We show that in this framework the (1+3)-universe is deeply connected with the (3+1)-universe. We argue that this means that in the (4+4)-universe there exists a duality relation between the (1+3)-universe and the (3+1)-universe.

关键词： Cosmological Model (4+4)-Dimensions Duality Symmetry

连续收获捕食者与脉冲存放食饵的阶段结构捕食-食饵模型的全局吸引和一致持久

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应用数学和力学 2008年第5期29卷 589-600页

作者：焦建军陈兰荪 j.j.尼托 T·A·安吉拉郭兴明(推荐) 贵州财经学院数学与统计学院贵阳550004 大连理工大学应用数学系辽宁大连116024 圣地亚哥-德孔波斯特拉大学数学学院数学分析系 15782圣地亚哥-德孔波斯特拉西班牙圣地亚哥-德孔波斯特拉大学医学院精神、放射和公众健康系15782圣地亚哥-德孔波斯特拉西班牙不详

研究了一个捕食者具连续收获与食饵具脉冲存放的阶段结构时滞捕食-食饵模型.根据生物资源管理的实际,改进了捕食者具阶段结构的捕食-食饵模型,即原来假设每个捕食者个体都具有相同的捕食食饵的能力.假设捕食者按年龄分为两个阶段,即幼... 详细信息

研究了一个捕食者具连续收获与食饵具脉冲存放的阶段结构时滞捕食-食饵模型.根据生物资源管理的实际,改进了捕食者具阶段结构的捕食-食饵模型,即原来假设每个捕食者个体都具有相同的捕食食饵的能力.假设捕食者按年龄分为两个阶段,即幼体和成体,而且幼体无能力捕食食饵.得到了捕食者灭绝周期解全局吸引和系统持久的充分条件.结论说明了脉冲存放食饵对系统的持久起了重要的作用,并且为生物资源管理提供了策略基础.数值分析也进一步说明了系统的动力学性质.

关键词：阶段结构脉冲存放连续收获全局吸引持久

CONTROLLABILITY AND OPTIMALITY OF LINEAR TIME-INVARIANT NEUTRAL CONTROL SYSTEMS WITH DIFFERENT FRACTIONAL ORDERS

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Acta Mathematica Scientia 2015年第5期35卷 1003-1013页

作者：丁小丽 juan j.nieto Department of Mathematics Xi’an Polytechnic University Departamento de Análisis Matemático Facultad de MatemáticasUniversidad de Santiago de Compostela Department of Mathematics Faculty of Science King Abdulaziz University

Control systems governed by linear time-invariant neutral equations with different fractional orders are considered. Sufficient and necessary conditions for the controllability of those systems are established. The existence of optimal controls for the systems is given. Finally, two examples are provided to show the application of our results.

关键词： controllability optimality neutral equations different fractional orders

SOLVABILITY OF AN IMPLICIT FRACTIONAL INTEGRAL EQUATION VIA A MEASURE OF NONCOMPACTNESS ARGUMENT

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Acta Mathematica Scientia 2017年第1期37卷 195-204页

作者： juan j.nieto Bessem SAMET Facultade de Matemáticas Universidade de Santiago de CompostelaSantiago de Compostela 15782Spain Faculty of Science King Abdulaziz UniversityJeddah 21589Saudi Arabia Department of Mathematics College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia

In this paper,we study the existence of solutions to an implicit functional equation involving a fractional integral with respect to a certain function,which generalizes the Riemann-Liouville fractional integral and the Hadaniard fractional *** establish an existence result to such kind of equations using a generalized version of Darbo＇s theorem associated to a certain measure of *** examples are presented.

关键词： umplicit fractional integral equation measure of noncompactness Darbo'stheorem

Existence and Uniqueness of Fixed Point in Partially Ordered Sets and Applications to Ordinary Differential Equations

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Acta Mathematica Sinica,English Series 2007年第12期23卷 2205-2212页

作者： juan j.nieto RosanaRODRGUEZ-LPEZ Departamento de Análisis Matemático Facultad de MatemáticasUniversidad de Santiago de Compostela

We prove some fixed point theorems in partially ordered sets, providing an extension of the Banach contractive mapping theorem. Having studied previously the nondecreasing case, we consider in this paper nonincreasing mappings as well as non monotone mappings. We also present some applications to first-order ordinary differential equations with periodic boundary conditions, proving the existence of a unique solution admitting the existence of a lower solution.

关键词： fixed point partially ordered set first-order differential equation lower and upper solutions

Impulsive perturbation and bifurcation of solutions for a model of chemostat with variable yield

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Applied Mathematics and Mechanics(English Edition) 2009年第7期30卷 933-944页

作者：张弘 Paul Georgescu juan j.nieto 陈兰荪 Department of Mathematics Jiangsu University Department of Mathematics and Mathematical Statistics Ume University Department of Mathematics "Gh.Asachi" Technical University of Iasi Departamento de Análisis Matemático Facultad de Matemáticas Universidadde Santiago de Compostela Institute of Mathematics Chinese Academy of Sciences

In this paper, we consider a variable yield model of a single-species growth in a well-stirred tank containing fresh medium, assuming the instances of time as triggering factors in which the nutrient refilling process and the removal of microorganisms by the uptake of lethal external antibiotic are initiated. It is also assumed that the periodic nutrient refilling and the periodic antibiotic inj.ction occur with the same periodicity, but not simultaneously. The model is then formulated in terms of autonomous differential equations subj.ct to impulsive perturbations. It is observed that either the population of microorganisms essentially washes out, or more favorably, the system is permanent. To describe this dichotomy, some biologically significant integral conditions are introduced. Further, it is shown that in a certain critical situation, a nontriviai periodic solution emerges via a bifurcation phenomenon. Finally, the dynamics of the model is illustrated with numerical experiments and computer simulations.

关键词： chemostat impulsive differential equation permanence extinction fixedpoint approach bifurcation

Mathematical analysis of Hepatitis C Virus infection model in the framework of non-local and non-singular kernel fractionalderivative

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International j.urnal of Biomathematics 2023年第1期16卷 77-96页

作者： Ibrahim Slimane Ghazala Nazir juan j.nieto Faheem Yaqoob Faculty of Eaact Sciences and Informatics UMABAbdelhamid IbnBadis P.O.Bor 227 University of Mostaganem 27000Mostaganem Algeria Department of Mathematics Universityof Malakand KhyberPakhtunkhawa Pakistan ghazalanazir732@*** Department of Statistics Mathematical Analysis and Optimization Galician Center for Mathematical Research and Technology University of Santiago de Compostela 15782 Santiago de Compostela Spain Department of Computer Sciences and Information Technology University of Poonch Rawalakot Azad Kashmir Pakistan

In this paper,we study a mathematical model of Hepatitis C Virus(HCV)*** present a compartmental mathematical model involving healthy hepatocytes,infected hepatocytes,non-activated dendritic cells,activated dendritic cells and cytotoxic T *** derivative used is of non-local fractional order and with non-singular *** existence and uniqueness of the system is proven and its stability is ***,by applying the Laplace Adomian decomposition method for the fractional derivative,we present the semi-analytical solution of the ***,some numerical simulations are performed for concrete values of the parameters and several graphs are plotted to reveal the qualitative properties of the solutions.

关键词： Hepatitis C virus(HCV) infection dendritic cells(DC) cytotoxic T lymphocytes(CTL) Atangana-Baleanu(AB) Laplace Adomians decomposition method(LADM).

Permanence and global attractivity of stage-structured predator-prey model with continuous harvesting on predator and impulsive stocking on prey

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Applied Mathematics and Mechanics(English Edition) 2008年第5期29卷 653-663页

作者：焦建军陈兰荪 juan j.nieto Torres Angela School of Mathematics and Statistics Guizhou College of Finance and Economics Department of Applied Mathematics Dalian University of Technology Department of Mathematical Analysis Faculty of MathematicsUniversity of Santiago de Compostela15782 Santiago de Compostela Spain Department of Psychiatry Radiology and Public Health Faculty of Medicine University of Santiago de CompostelaSpain

We investigate a stage-structured delayed predator-prey model with impulsive stocking on prey and continuous harvesting on predator. According to the fact of biological resource management, we improve the assumption of a predator-prey model with stage structure for predator population that each individual predator has the same ability to capture prey. It is assumed that the immature and mature individuals of the predator population are divided by a fixed age, and immature predator population does not have the ability to attach prey. Sufficient conditions are obtained, which guarantee the global attractivity of predator-extinction periodic solution and the permanence of the system. Our results show that the behavior of impulsive stocking on prey plays an important role for the permanence of the system, and provide tactical basis for the biological resource management. Numerical analysis is presented to illuminate the dynamics of the system.

关键词： stage-structured, impulsive stocking continuous harvesting global attractivity permanence