Islamic Azad University, Central tehran BranchInternational Journal of Mathematical Modelling & Computations2228-6225102 (SPRING)20200620The Position of Multiobjective Programming Methods in Fuzzy Data Envelopment Analysis95101674189ENParichehrZamaniFaculty of Engineering, Qom Branch, Islamic Azad University, Qom, Iran.Journal Article20200213Traditional Data Envelopment Analysis (DEA) models evaluate the efficiency of decision making units (DMUs) with common crisp input and output data. However, the data in real applications are often imprecise or ambiguous. This paper transforms fuzzy fractional DEA model constructed using fuzzy arithmetic, into the conventional crisp model. This transformation is performed considering the goal programming that is one of the Multi Objective Programming (MOP) methods. Therefore, in this research the one linear programming model measures the fuzzy efficiencies of DMUs with fuzzy input and fuzzy output data.http://ijm2c.iauctb.ac.ir/article_674189_4d86985007bdd58d311470c4c990381b.pdfIslamic Azad University, Central tehran BranchInternational Journal of Mathematical Modelling & Computations2228-6225102 (SPRING)20200620Modeling and Analysis of Vehicles Flow on the Road103110674190ENKumama RegassaChenekeWollega UniversityPurnachandra RaoKoyaWollega UniversityGeremew KenassaEdessaWollega UniversityJournal Article20200117Abstract: This study is carried out to describe the behaviour of vehicles flow on the road, in the presence of blocking effects. A non-linear three dimensional system of ordinary differential equations is used to describe vehicles flow on the road. The study classify total vehicles population on the road into three compartments as Free – Slow – Released vehicles. The formulated model is well-posed. The blocking free equilibrium point is globally asymptotically stable. Further, effects of blocking are described using concept of retardation number. That is, blocking effect decrease whenever retardation number is less than one and the blocking effects increase if retardation number is greater than one.http://ijm2c.iauctb.ac.ir/article_674190_e9abf6f9855d5a88b12bf0ce06b1d492.pdfIslamic Azad University, Central tehran BranchInternational Journal of Mathematical Modelling & Computations2228-6225102 (SPRING)20200620Relativistic Stellar Models with Quadratic Equation of State111124674191ENManuelMalaverMaritime University of the Caribbean, Department of Basic Sciences, Catia la Mar, Venezuela.0000-0002-2797-3174HamedDaei KasmaeiDepartment of Mathematics and Statistics , Faculty of Science ,Central Tehran Branch
,Islamic Azad University ,Tehran, Iran0000-0002-5114-9361Journal Article20200201In this paper, we have obtained and presented new relativistic stellar configurations considering an anisotropic fluid distribution with a charge distribution and a gravitational potential Z(x) that depends on an adjustable parameter. The quadratic equation of state based on Feroze and Siddiqui viewpoint is used for the matter distribution. The new solutions can be written in terms of elementary and polynomial functions. We have investigated that the radial pressure, metric coefficients, energy density, anisotropy factor, charge density, mass function have been well defined and are regular in the interior of these new models, which satisfy all physical properties in a realistic star.http://ijm2c.iauctb.ac.ir/article_674191_58e74683228389f99bea7d2122ae79cd.pdfIslamic Azad University, Central tehran BranchInternational Journal of Mathematical Modelling & Computations2228-6225102 (SPRING)20200620Probability Distribution Fitting to Maternal Mortality in Nigeria.125132674818ENIsqeel AdesegunOgunsolaDepartment of Statistics, College of Physical Sciences, Federal University of Agriculture, Abeokuta, Ogun State0000-0003-2272-1530Jeremiah OlajideAkinpeloyeDepartment of Epidemiology, Faculty of Publich Health, University of IbadanLawal AdekunleDadaDepartment of Statistics, University of Ibadan, NigeriaJournal Article20200229The consequences of Maternal Mortality (MM) cannot be overemphasized. It inhibits population growth resulting into loss of lives among others. This work tends to obtain the maternal mortality rates (MMR) in Nigeria, identify some fitted distributions to MMR and determine which of the distributions best fits the data. A comprehensive Exploratory Data Analysis (EDA) was carried on MM and the MMRs were obtained. Two parameters Gamma distribution, Weibull and Exponential distributions were fitted for MM. Both BIC and AIC selection criteria were adopted in selecting the most fitted distribution. The AIC for Gamma, Weibull and Exponential distributions fitted for MMR were 1339.396, 1340.161 and 370.5244 respectively. Also, the BIC for Gamma, Weibull and Exponential distributions fitted for MM were 1344.971, 1345.736 and 373.3119 respectively. It can be observed that Exponential distribution has the least AIC (370.5244) and least BIC (373.3119), therefore, it is the most fitted distribution for MM. The estimate (standard error) of exponential distribution on MM is 0.5853 indicating the fitness of the distribution being the one with the least error. Conclusively, the model obtained from this study can be used to study and monitor MM in Nigeria to achieve a better economy and thus brings about local and national development.http://ijm2c.iauctb.ac.ir/article_674818_6659fbb69d6232c2795c0cd58d8304a0.pdfIslamic Azad University, Central tehran BranchInternational Journal of Mathematical Modelling & Computations2228-6225102 (SPRING)20200620Proposing A stochastic model for spread of corona virus dynamics in Nigeria133140674192ENAliyu UsmanKinafaDepartment of Mathematics, Gombe State UniversityJournal Article20200301The emergence of corona virus (COVID-19) has create a great public concern as the outbreak is still ongoing and government are taking actions such as holiday extension, travel restriction, temporary closure of public work place, borders, schools, quarantine/isolation, social distancing and so on. To mitigate the spread, we proposed and analyzed a stochastic model for the continue spread of corona virus (COVID-19) dynamics considering the impact of vaccination among susceptible, exposed and quarantine cases. The difference and differential-difference equations for the dynamics of (COVID-19) were derived and simulated with available parameters using stochastic simulation (Gillespie Algorithm). The study adopts Continues–Time Birth and Death stochastic process and the probability distribution describing the dynamics of coronavirus was derived and simulated which shows an exponential decay over time. As the time increase, the probability of coronavirus incidents decline to zero. We therefore conclude that vaccination has an impact of 20% among susceptible, exposed and quarantine cases.http://ijm2c.iauctb.ac.ir/article_674192_e29488facdde855f1e737477cb39e866.pdfIslamic Azad University, Central tehran BranchInternational Journal of Mathematical Modelling & Computations2228-6225102 (SPRING)20200620Mathematical Model of Novel COVID-19 and Its Transmission Dynamics141159674194ENEshetu DadiGurmuMathematics, Natural Science,Wollega,Nekemte, Ethiopia0000-0003-3209-5844Getachew BeyechaBatuDepartment of Mathematics, Applied Natural Science, Adama Science and Technology University, Adama, EthiopiaMamo ShiguteWamekoMathematics, College of Natural and computational science, Nekemte, Ethiopia0000-0003-4246-9651Journal Article20200305In this paper, we formulated a dynamical model of COVID-19 to describe the transmission dynamics of the disease. The well possedness of the formulated model equations was proved. Both local and global stability of the disease free equilibrium and endemic equilibrium point of the model equation was established using basic reproduction number. The results show that, if the basic reproduction number is less than one then the solution converges to the disease free steady state i.e. the disease free equilibrium is asymptotically stable. The endemic states are considered to exist when the basic reproduction number for each disease is greater than one. Numerical simulation carried out on the model revealed that an increase in level of contact rate among individuals has an effect on reducing the prevalence of COVID-19 and COVID-19 disease. Furthermore, sensitivity analysis of the model equation was performed on the key parameters to find out their relative significance and potential impact on the transmission dynamics of COVID-19.http://ijm2c.iauctb.ac.ir/article_674194_369926698314a67c3676fe6d45ee3db8.pdf