AppliedMath最新文献_第3页

Decompositions of the λ-Fold Complete Mixed Graph into Mixed 6-Stars 将 λ 折叠完整混合图分解为混合六星图

AppliedMath Pub Date : 2024-02-05 DOI: 10.3390/appliedmath4010011

Robert Gardner, Kazeem Kosebinu

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引用次数: 0

Decompositions of the λ-Fold Complete Mixed Graph into Mixed 6-Stars 将 λ 折叠完整混合图分解为混合六星图

AppliedMath Pub Date : 2024-02-05 DOI: 10.3390/appliedmath4010011

Robert Gardner, Kazeem Kosebinu

{"title":"Decompositions of the λ-Fold Complete Mixed Graph into Mixed 6-Stars","authors":"Robert Gardner, Kazeem Kosebinu","doi":"10.3390/appliedmath4010011","DOIUrl":"https://doi.org/10.3390/appliedmath4010011","url":null,"abstract":"Graph and digraph decompositions are a fundamental part of design theory. Probably the best known decompositions are related to decomposing the complete graph into 3-cycles (which correspond to Steiner triple systems), and decomposing the complete digraph into orientations of a 3-cycle (the two possible orientations of a 3-cycle correspond to directed triple systems and Mendelsohn triple systems). Decompositions of the λ-fold complete graph and the λ-fold complete digraph have been explored, giving generalizations of decompositions of complete simple graphs and digraphs. Decompositions of the complete mixed graph (which contains an edge and two distinct arcs between every two vertices) have also been explored in recent years. Since the complete mixed graph has twice as many arcs as edges, an isomorphic decomposition of a complete mixed graph into copies of a sub-mixed graph must involve a sub-mixed graph with twice as many arcs as edges. A partial orientation of a 6-star with two edges and four arcs is an example of such a mixed graph; there are five such mixed stars. In this paper, we give necessary and sufficient conditions for a decomposition of the λ-fold complete mixed graph into each of these five mixed stars for all λ>1.","PeriodicalId":503400,"journal":{"name":"AppliedMath","volume":"66 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139863447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Convection of Physical Quantities of Random Density 随机密度物理量的对流

AppliedMath Pub Date : 2024-02-05 DOI: 10.3390/appliedmath4010012

E. Barletta, S. Dragomir, Francesco Esposito

引用次数: 0

Cell-Cycle Synchronization Prior to Radiotherapy: A Mathematical Model of the Use of Gemcitabine on Melanoma Xenografts 放疗前的细胞周期同步：在黑色素瘤异种移植物上使用吉西他滨的数学模型

AppliedMath Pub Date : 2024-02-04 DOI: 10.3390/appliedmath4010010

Frederika Rentzeperis, Benjamin Coleman, Dorothy Wallace

引用次数: 0

Cell-Cycle Synchronization Prior to Radiotherapy: A Mathematical Model of the Use of Gemcitabine on Melanoma Xenografts 放疗前的细胞周期同步：在黑色素瘤异种移植物上使用吉西他滨的数学模型

AppliedMath Pub Date : 2024-02-04 DOI: 10.3390/appliedmath4010010

Frederika Rentzeperis, Benjamin Coleman, Dorothy Wallace

引用次数: 0

A Model of Hepatitis B Viral Dynamics with Delays 带延迟的乙型肝炎病毒动态模型

AppliedMath Pub Date : 2024-02-01 DOI: 10.3390/appliedmath4010009

B. Chen-Charpentier

{"title":"A Model of Hepatitis B Viral Dynamics with Delays","authors":"B. Chen-Charpentier","doi":"10.3390/appliedmath4010009","DOIUrl":"https://doi.org/10.3390/appliedmath4010009","url":null,"abstract":"Hepatitis B is a liver disease caused by the human hepatitis B virus (HBV). Mathematical models help further the understanding of the processes involved and help make predictions. The basic reproduction number, R0, is an index that predicts whether the disease will be chronic or not. This is the single most-important information that a mathematical model can give. Within-host virus processes involve delays. We study two within-host hepatitis B virus infection models without and with delay. One is a standard one, and the other considering additional processes and with two delays is new. We analyze the basic reproduction number and alternative threshold indices. The values of R0 and the alternative indices change depending on the model. All these indices predict whether the infection will persist or not, but they do not give the same rate of growth of the infection when it is starting. Therefore, the choice of the model is very important in establishing whether the infection is chronic or not and how fast it initially grows. We analyze these indices to see how to decrease their value. We study the effect of adding delays and how the threshold indices depend on how the delays are included. We do this by studying the local asymptotic stability of the disease-free equilibrium or by using an equivalent method. We show that, for some models, the indices do not change by introducing delays, but they change when the delays are introduced differently. Numerical simulations are presented to confirm the results. Finally, some conclusions are presented.","PeriodicalId":503400,"journal":{"name":"AppliedMath","volume":"321 ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139826722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Model of Hepatitis B Viral Dynamics with Delays 带延迟的乙型肝炎病毒动态模型

AppliedMath Pub Date : 2024-02-01 DOI: 10.3390/appliedmath4010009

B. Chen-Charpentier

{"title":"A Model of Hepatitis B Viral Dynamics with Delays","authors":"B. Chen-Charpentier","doi":"10.3390/appliedmath4010009","DOIUrl":"https://doi.org/10.3390/appliedmath4010009","url":null,"abstract":"Hepatitis B is a liver disease caused by the human hepatitis B virus (HBV). Mathematical models help further the understanding of the processes involved and help make predictions. The basic reproduction number, R0, is an index that predicts whether the disease will be chronic or not. This is the single most-important information that a mathematical model can give. Within-host virus processes involve delays. We study two within-host hepatitis B virus infection models without and with delay. One is a standard one, and the other considering additional processes and with two delays is new. We analyze the basic reproduction number and alternative threshold indices. The values of R0 and the alternative indices change depending on the model. All these indices predict whether the infection will persist or not, but they do not give the same rate of growth of the infection when it is starting. Therefore, the choice of the model is very important in establishing whether the infection is chronic or not and how fast it initially grows. We analyze these indices to see how to decrease their value. We study the effect of adding delays and how the threshold indices depend on how the delays are included. We do this by studying the local asymptotic stability of the disease-free equilibrium or by using an equivalent method. We show that, for some models, the indices do not change by introducing delays, but they change when the delays are introduced differently. Numerical simulations are presented to confirm the results. Finally, some conclusions are presented.","PeriodicalId":503400,"journal":{"name":"AppliedMath","volume":"60 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139886828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A Co-Infection Model for Onchocerciasis and Lassa Fever with Optimal Control Analysis 带最优控制分析的盘尾丝虫病和拉沙热双重感染模型

AppliedMath Pub Date : 2024-01-10 DOI: 10.3390/appliedmath4010006

Kabiru Michael Adeyemo, K. Oshinubi, U. M. Adam, Adejimi Adeniji

{"title":"A Co-Infection Model for Onchocerciasis and Lassa Fever with Optimal Control Analysis","authors":"Kabiru Michael Adeyemo, K. Oshinubi, U. M. Adam, Adejimi Adeniji","doi":"10.3390/appliedmath4010006","DOIUrl":"https://doi.org/10.3390/appliedmath4010006","url":null,"abstract":"A co-infection model for onchocerciasis and Lassa fever (OLF) with periodic variational vectors and optimal control is studied and analyzed to assess the impact of controls against incidence infections. The model is qualitatively examined in order to evaluate its asymptotic behavior in relation to the equilibria. Employing a Lyapunov function, we demonstrated that the disease-free equilibrium (DFE) is globally asymptotically stable; that is, the related basic reproduction number is less than unity. When it is bigger than one, we use a suitable nonlinear Lyapunov function to demonstrate the existence of a globally asymptotically stable endemic equilibrium (EE). Furthermore, the necessary conditions for the presence of optimum control and the optimality system for the co-infection model are established using Pontryagin’s maximum principle. The model is quantitatively analyzed by studying how sensitive the basic reproduction number is to the model parameters and the model simulation using Runge–Kutta technique of order 4 is also presented to study the effects of the treatments. We deduced from the quantitative analysis that, if there is an effective treatment and diagnosis of those exposed to and infected with the disease, the spread of the viral disease can be effectively managed. The results presented in this work will be useful for the proper mitigation of the disease.","PeriodicalId":503400,"journal":{"name":"AppliedMath","volume":"4 12","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139439193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Informational Updates and the Derivative Pricing Kernel 信息更新与衍生品定价内核

AppliedMath Pub Date : 2024-01-03 DOI: 10.3390/appliedmath4010005

Ayan Bhattacharya

引用次数: 0

Dynamics of the Isotropic Star Differential System from the Mathematical and Physical Point of Views 从数学和物理学角度看各向同性星体差分系统的动力学特性

AppliedMath Pub Date : 2024-01-02 DOI: 10.3390/appliedmath4010004

Joan C. Artés, J. Llibre, N. Vulpe

引用次数: 0