American journal of applied mathematics and statistics最新文献_第9页

General Solutions of Some Complex Third-order Differential Equations 一类复杂三阶微分方程的通解

American journal of applied mathematics and statistics Pub Date : 2020-12-08 DOI: 10.11648/J.AJAM.20200806.14

R. Liao, Zhibo Huang

引用次数: 0

Continued Fraction Expansion of the Heinz Operator Mean Heinz算子均值的连分式展开

American journal of applied mathematics and statistics Pub Date : 2020-12-07 DOI: 10.11648/J.AJAM.20200806.13

Kacem Belhroukia, S. Salhi, A. Kacha

引用次数: 0

A Family of Global Attractors for the Higher-order Kirchhoff-type Equations and Its Dimension Estimation 一类高阶kirchhoff型方程的全局吸引子及其维数估计

American journal of applied mathematics and statistics Pub Date : 2020-11-24 DOI: 10.11648/J.AJAM.20200806.12

Guoguang Lin, Yuhang Chen

引用次数: 4

Modeling Frequency and Severity of Insurance Claims in an Insurance Portfolio 保险组合中保险索赔的频率和严重程度建模

American journal of applied mathematics and statistics Pub Date : 2020-11-11 DOI: 10.12691/AJAMS-8-3-4

James Kiprotich Ng’elechei, J. Chelule, H. Orango, Thomas Mageto, A. Anapapa

{"title":"Modeling Frequency and Severity of Insurance Claims in an Insurance Portfolio","authors":"James Kiprotich Ng’elechei, J. Chelule, H. Orango, Thomas Mageto, A. Anapapa","doi":"10.12691/AJAMS-8-3-4","DOIUrl":"https://doi.org/10.12691/AJAMS-8-3-4","url":null,"abstract":"Premium pricing is always a challenging task in general insurance. Furthermore, frequency of the insurance claims plays a major role in the pricing of the premiums. Severity in insurance on the other hand, can either be the amount paid due to a loss or the size of the loss event. For insurer’s to be in a position to settle claims that occur from existing portfolios of policies in future, it is necessary that they adequately model past and current data on claim experience then use the models to project the expected future experience in claim amounts. In addition, non-life insurance companies are faced with problems when modeling claim data i.e selecting appropriate statistical distribution and establishing how well it fits the claimed data. Therefore, the study presents a framework for choosing the most suitable probability distribution and fitting it to the past motor claims data and the parameters are estimated using maximum likelihood method (MLE). The goodness of fit of frequency distributions was checked using the chi-square test and Anderson-Darling tests was applied to severity claim distributions. Best chosen models from frequency models and severity models were used to estimate the expected claim amount per risk in the following year. The study employed AIC to choose between competing models. Pareto and Negative Binomial model best fit severity claims, and frequency claims respectively. The two models were used for projection.","PeriodicalId":91196,"journal":{"name":"American journal of applied mathematics and statistics","volume":"37 1","pages":"103-111"},"PeriodicalIF":0.0,"publicationDate":"2020-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81362289","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: 2

Reliability Systems and Optimal Control – Goal Realization Probability 可靠性系统和最优控制-目标实现概率

American journal of applied mathematics and statistics Pub Date : 2020-11-11 DOI: 10.11648/J.AJAM.20200806.11

Aleksandra Rajcevic

{"title":"Reliability Systems and Optimal Control – Goal Realization Probability","authors":"Aleksandra Rajcevic","doi":"10.11648/J.AJAM.20200806.11","DOIUrl":"https://doi.org/10.11648/J.AJAM.20200806.11","url":null,"abstract":"In this theoretical article is considered reliability cybernetics systems with probability theory. Optimal control and managing assigned goals of system are considered after control actions were assigned with a determined probability of realization. Real system is set of elements functionally connected in one whole for achieving determined goal using, transforming and exchanging energy, resources and informations. Real system mainly is presented as functional and physical whole. System researched by cybernetics could be school, metallic company or concrete factory. New concepts are involved in researching cybernetics systems reliability systems and optimal control. Controlling system is an action on object of control which optimized functioning of that object. Optimal control is substituted set of control actions which are got favorable optimal criterion value. Optimal criterions are considered as values of gains or value of losses. Reliability systems is property of system to realize his function or goal with some probability, having in mind reliability all of system elements. Realization wanted output or goal realization is calculated as intersection projected system parts realizations with determined probability. In this paper will be shown three different systems regarded to how they executed their controlling actions. Probability of realization system goals are calculated for two cases: maximum and minimum reliability. Intention is to show and calculate reliability systems with high human resources representation.","PeriodicalId":91196,"journal":{"name":"American journal of applied mathematics and statistics","volume":"43 1","pages":"293"},"PeriodicalIF":0.0,"publicationDate":"2020-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90596320","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

Extended Cox Model on Duration Taken to Release Cargo at Kenyan Border Entry Point: A Case Study of Malaba Osbp 肯尼亚边境口岸货物放行时间的扩展Cox模型:以马拉巴口岸为例

American journal of applied mathematics and statistics Pub Date : 2020-11-06 DOI: 10.12691/ajams-8-3-3

Kennedy Ekeya Emoru, J. Chelule, Herbert Orango Imboga, A. Anapapa

{"title":"Extended Cox Model on Duration Taken to Release Cargo at Kenyan Border Entry Point: A Case Study of Malaba Osbp","authors":"Kennedy Ekeya Emoru, J. Chelule, Herbert Orango Imboga, A. Anapapa","doi":"10.12691/ajams-8-3-3","DOIUrl":"https://doi.org/10.12691/ajams-8-3-3","url":null,"abstract":"Duration taken to release cargo is one of World Customs Organisationi¯s most significant instruments of measuring trade facilitation. It is a way of reviewing clearance procedure by measuring the time taken to release cargo at border entry points. This research therefore aimed to model clearance time using the Extended Cox model, which is a modification of the proportional hazard Cox model in which proportional hazard assumptions are not met, and tested the practicability of the model and compared the performance of Extended Cox model with the other conventional methods using secondary data on time clearance that was obtained from the KRA, Malaba OSBP, for the period 1st January 2015 to 31st July 2019. The variables in the study were both time depend (time taken from registration to release) and time independent (customs regimes, origin, destination, customs value and description of goods). The variables used in the research project were tested for proportional hazard assumptions. Extended Cox model was the most suitable model for analysis duration taken to release cargo data has it was found to have a lower AIC and BIC as compared to conventional cox model. Therefore, customs administration should embrace the use of Extended Cox model to analysis duration taken to release cargo data as it is statistically significant and give efficient results that are based on proper statistical methods. It is recommended that further studies to be done on a large data set that encompasses both entry and exit cargo in all the Kenyan border points.","PeriodicalId":91196,"journal":{"name":"American journal of applied mathematics and statistics","volume":"94 1","pages":"96-102"},"PeriodicalIF":0.0,"publicationDate":"2020-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83872954","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 Free Boundary Problem for a Leslie-Gower Predator-Prey Model in Higher Dimensions and Heterogeneous Environment 高维异构环境下Leslie-Gower捕食-食饵模型的自由边界问题

American journal of applied mathematics and statistics Pub Date : 2020-10-27 DOI: 10.11648/J.AJAM.20200805.17

Shiwen Niu, Hongmei Cheng

{"title":"A Free Boundary Problem for a Leslie-Gower Predator-Prey Model in Higher Dimensions and Heterogeneous Environment","authors":"Shiwen Niu, Hongmei Cheng","doi":"10.11648/J.AJAM.20200805.17","DOIUrl":"https://doi.org/10.11648/J.AJAM.20200805.17","url":null,"abstract":"This paper is mainly concerned with some free boundary problems for a modified Leslie-Gower predator-prey model in higher dimensional and heterogeneous environment. To keep it simple in this article, we assume that the environment and solutions are all radially symmetric. We consider the problem which be used to describe the spreading of an introduced predator species in higher dimensional and heterogeneous environment. We will assume that the prey is initially uniformly well disturbed. The prey undergoes the diffusion and growth in the entire space R^n. The predator is initially introduced in some localized location. We establish that a spreading-vanishing dichotomy is held for this model. We use the comparison principle. we will give the existence, uniqueness and some estimates of the solution to the problem. We study the asymptotic behavior of two species evolving. The free boundary represents the spreading front of the predator species. The boundary condition is described by classic Stefan-like condition. It is proved that the problem addressed is well posed, and that the predator species disperses to all domains in finite time. The long time behaviors of solution and criteria for spreading and vanishing of predator species are also provided. Furthermore, in the case that spreading of predator species happens, we deduce some rough estimates of the spreading speed.","PeriodicalId":91196,"journal":{"name":"American journal of applied mathematics and statistics","volume":"8 1","pages":"284"},"PeriodicalIF":0.0,"publicationDate":"2020-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88917826","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: 1

Local Approximate Forward Attractors of Nonautonomous Dynamical Systems 非自治动力系统的局部逼近正向吸引子

American journal of applied mathematics and statistics Pub Date : 2020-09-25 DOI: 10.11648/J.AJAM.20200805.16

Ailing Qi, Xuewei Ju

引用次数: 0

Control of Cauchy Problem for a Laplacian Operator 拉普拉斯算子Cauchy问题的控制

American journal of applied mathematics and statistics Pub Date : 2020-09-22 DOI: 10.11648/J.AJAM.20200805.15

Sadou Tao

{"title":"Control of Cauchy Problem for a Laplacian Operator","authors":"Sadou Tao","doi":"10.11648/J.AJAM.20200805.15","DOIUrl":"https://doi.org/10.11648/J.AJAM.20200805.15","url":null,"abstract":"In this paper we study the control of an ill-posed system relating to the Cauchy problem for an elliptical operator. The control of Cauchy systems for an elliptical operator has already been studied by many authors. But it still seems to be globally an open problem. Of all the studies that have been done on this problem, it is assumed that the set of admissible couple-state must be nonempty to make sense of the problem. This is the case of J. L. Lions in [6] who gave various examples of the admissible set to make a sense of the problem. O. Nakoulima in [9] uses the regularization-penalization method to approach the problem by a sequence of well-posed control problems, he obtains the convergence of the processus in a particular case of the admissible set. G. Mophou and O. Nakoulima in [10] do the same study and obtain the convergence of the processus when the interior of the admissible set is non empty. In this work, we give an approximate solution without an additional condition on the set of admissible couple-state.We propose a method which consists in associating with the singular control problem a \"family\" of controls of well posed problems. We propose as an alternative the stackelberg control which is a multiple-objective optimization approach proposed by H. Von Stackelberg in [12].","PeriodicalId":91196,"journal":{"name":"American journal of applied mathematics and statistics","volume":"110 1","pages":"271"},"PeriodicalIF":0.0,"publicationDate":"2020-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81989425","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

Approximate Numerical Solution of Singular Integrals and Singular Initial Value Problems 奇异积分与奇异初值问题的近似数值解

American journal of applied mathematics and statistics Pub Date : 2020-09-22 DOI: 10.11648/J.AJAM.20200805.14

Md. Habibur Rahaman, M Zahid Hasan, Md. Ayub Ali, Md. Shamsul Alam

{"title":"Approximate Numerical Solution of Singular Integrals and Singular Initial Value Problems","authors":"Md. Habibur Rahaman, M Zahid Hasan, Md. Ayub Ali, Md. Shamsul Alam","doi":"10.11648/J.AJAM.20200805.14","DOIUrl":"https://doi.org/10.11648/J.AJAM.20200805.14","url":null,"abstract":"Numerical integration is one of the important branch of mathematics. Singular integrals arises in different applications in applied and engineering mathematics. The evaluation of singular integrals is one of the most challenging jobs. Earlier different techniques were developed for evaluating such integrals, but these were not straightforward. Recently various order straightforward formulae have been developed for evaluating such integrals but; all these integral formulae depend on Romberg technique for more accurate results. Based on these integral formulae, different order (up to fifth) implicit methods have been developed for solving singular initial value problems. These implicit methods give better results than those obtained by implicit Runge-Kutta methods but; the derivation of such higher order formulae are not so easy. In this article, a new third order straightforward integral formula has been proposed for evaluating singular integrals. This new formula is able to evaluate more efficiently than others existing formulae, moreover it has the independent ability to calculate very near accurate result to the exact value of the numerical integrals. Based on this new integral formula a new third order implicit method has been proposed for solving singular initial value problems. The new method provides significantly better results than other existing methods.","PeriodicalId":91196,"journal":{"name":"American journal of applied mathematics and statistics","volume":"70 1","pages":"265"},"PeriodicalIF":0.0,"publicationDate":"2020-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90247160","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