-
Effects of Variable Viscosity on Unsteady Natural Convection Hydromagnetic Flow Past an Isothermal Sphere
Mwangi Wanjiku Lucy,
Mathew Ngugi Kinyanjui,
Roy Phineas Kiogora
Issue:
Volume 4, Issue 6, December 2016
Pages:
258-270
Received:
13 September 2016
Accepted:
2 October 2016
Published:
1 November 2016
Abstract: In this study, the effects of variable viscosity on unsteady natural convection hydromagnetic flow past an isothermal sphere are determined. The uniformly heated sphere is immersed in a viscous and incompressible fluid where viscosity of the fluid is taken as a linear function of temperature. The Partial Differential Equations governing the flow are reduced into non dimensional form and since these equations are non-linear, they are solved numerically using finite difference methods. The numerical results obtained are presented graphically and discussed. It has been observed that there is a significant change in primary velocity, secondary velocity, temperature, skin friction and heat transfer of the fluid with changes in Reynolds number, Grashof number, Magnetic parameter and viscous variation parameter. These results are applicable in engineering, technology and biomedical fields.
Abstract: In this study, the effects of variable viscosity on unsteady natural convection hydromagnetic flow past an isothermal sphere are determined. The uniformly heated sphere is immersed in a viscous and incompressible fluid where viscosity of the fluid is taken as a linear function of temperature. The Partial Differential Equations governing the flow ar...
Show More
-
Solving Porous Medium Equation Using Aboodh Transform Homotopy Perturbation Method
Issue:
Volume 4, Issue 6, December 2016
Pages:
271-276
Received:
18 September 2016
Accepted:
10 October 2016
Published:
1 November 2016
Abstract: In this paper, a new technique has been used forsolving the porous medium equation. This method is named by Aboodh transform which is a combination of the new integral transform “Aboodh transform” and the homotopy perturbation method. The nonlinear termin the porous medium equationscan be easily handled by homotopy perturbation method and some cases of these Equations are solved as examples to illustrate ability and reliability of mixture of Aboodh transform and homotopy perturbation method. The results reveal that the combination of Aboodh transform and homotopy perturbation methodis quite capable, practically well appropriate for usingsuch theproblems. Also, this method is found that a better alternative method to some existing techniques for such realistic problems.
Abstract: In this paper, a new technique has been used forsolving the porous medium equation. This method is named by Aboodh transform which is a combination of the new integral transform “Aboodh transform” and the homotopy perturbation method. The nonlinear termin the porous medium equationscan be easily handled by homotopy perturbation method and some case...
Show More
-
A New Entropy-based Intuitionistic Fuzzy Multi-attribute Decision Making Method
Issue:
Volume 4, Issue 6, December 2016
Pages:
277-282
Received:
6 October 2016
Accepted:
14 October 2016
Published:
7 November 2016
Abstract: The main task of this paper is to develop a new decision making method based on a novel entropy measure of intuitionistic fuzzy sets. First a novel intuitionistic fuzzy entropy is constructed, then based on this information measure, new weighting methods are proposed for the intuitionistic fuzzy decision making problems with the attribute weights are completely unknown or partly known. Further the intuitionistic fuzzy TOPSIS method is developed in this paper, and two examples are given to illustrate effectiveness and practicability of proposed method.
Abstract: The main task of this paper is to develop a new decision making method based on a novel entropy measure of intuitionistic fuzzy sets. First a novel intuitionistic fuzzy entropy is constructed, then based on this information measure, new weighting methods are proposed for the intuitionistic fuzzy decision making problems with the attribute weights a...
Show More
-
Asymptotic Optimal Empirical Bayes Estimation of the Parameter of ЭРланга Distribution
Issue:
Volume 4, Issue 6, December 2016
Pages:
283-288
Received:
6 October 2016
Accepted:
14 October 2016
Published:
7 November 2016
Abstract: This paper aims to study the empirical Bayes estimation of the parameter of ЭРланга distribution under a weighted squared error loss function. Bayes estimator is firstly to derive based on pivot method. Then empirical Bayes estimator of unknown parameter is constructed in a priori unknown circumstances. The asymptotically optimal property of this empirical Bayes estimator is also discussed. It is shown that the convergence rates of the proposed empirical Bayes estimator can arbitrarily close to O(n) -1) under suitable conditions.
Abstract: This paper aims to study the empirical Bayes estimation of the parameter of ЭРланга distribution under a weighted squared error loss function. Bayes estimator is firstly to derive based on pivot method. Then empirical Bayes estimator of unknown parameter is constructed in a priori unknown circumstances. The asymptotically optimal property of this e...
Show More
-
Mathematical Modelling of Epidemiology of Malaria: A Case Study of Luapula Province of Zambia
Justina Mulenga,
Leonard Mubila
Issue:
Volume 4, Issue 6, December 2016
Pages:
289-295
Received:
10 March 2016
Accepted:
18 March 2016
Published:
25 November 2016
Abstract: In this study, we use the SIR model proposed by Kermack and McKendrick to model the epidemiology of malaria in Luapula Province. Data collected from the District Health Management Teams in Luapula Province were used to analyse the rate of infection of malaria in the Province. The Reproduction number R0, was calculated and it was found if R0 >0, there will be malaria outbreak in the province and if R0<0, the disease will not evade the Province. From our analysis we found R0 >0 which implies that the force of malaria infection in the Province is high. We, therefore, make recommendations for the reduction of malaria in the Province.
Abstract: In this study, we use the SIR model proposed by Kermack and McKendrick to model the epidemiology of malaria in Luapula Province. Data collected from the District Health Management Teams in Luapula Province were used to analyse the rate of infection of malaria in the Province. The Reproduction number R0, was calculated and it was found if R0 >0, ...
Show More
-
Dufour and Soret Effects on MHD Forced Convective Heat and Mass Transfer Flow of Non-Newtonian Power Law Fluid with Thermal Radiation and Viscous Dissipation
Chinmayee Podder,
Md. Abdus Samad
Issue:
Volume 4, Issue 6, December 2016
Pages:
296-309
Received:
26 September 2016
Accepted:
1 November 2016
Published:
29 November 2016
Abstract: This paper investigates the Dufour and Soret effects of forced convection heat and mass transfer of an electrically conducting, non-Newtonian power-law fluid past a stretching sheet under the simultaneous action of suction, radiation, uniform transverse magnetic field, heat generation and viscous dissipation. The stretching sheet is assumed to continuously moving with a power-law velocity and maintaining a uniform surface heat flux. The governing nonlinear partial differential equations are transformed into a system of non linear ordinary differential equations using appropriate similarity transformations. The resulting dimensionless equations are solved numerically using sixth order Runge-Kutta integration scheme with Nachtsheim-Swigert shooting iterative technique. A systematical study of numerical results for the non-dimensional velocity, temperature and concentration profiles are presented graphically. The viscous drag or local Skin-friction coefficient, heat transfer rate or local Nusselt number and mass transfer rate or local Sherwood number are represented in tabular and graphical forms to illustrate the details of flow characteristics and their dependence on all physically important parameters in case of Newtonian and non-Newtonian (pseudo-plastic and dilatants) fluids.
Abstract: This paper investigates the Dufour and Soret effects of forced convection heat and mass transfer of an electrically conducting, non-Newtonian power-law fluid past a stretching sheet under the simultaneous action of suction, radiation, uniform transverse magnetic field, heat generation and viscous dissipation. The stretching sheet is assumed to cont...
Show More
-
Robust Optimization for Performance-Based Budget Allocation at Payam Noor University
Mohammad Mehdi Nasrabadi,
Elham Sharifi Rasouli,
Marziyeh Sharifi
Issue:
Volume 4, Issue 6, December 2016
Pages:
310-315
Received:
10 October 2016
Accepted:
12 November 2016
Published:
5 December 2016
Abstract: Budget allocation is a central problem in universities and research centers. Recently, Payam Noor University (PNU) has used a performance-based approach to allocate budget between proposed projects. Mathematically speaking, this can be modeled as an optimization problem, but in practice the parameters of the problem are subject to uncertainty and are not well-known in advance. This paper uses robust optimization to deal with uncertainty in budget allocation and present numerical results. Our results demonstrate the performance of robust optimization as an effective way to address uncertainty in budget allocation.
Abstract: Budget allocation is a central problem in universities and research centers. Recently, Payam Noor University (PNU) has used a performance-based approach to allocate budget between proposed projects. Mathematically speaking, this can be modeled as an optimization problem, but in practice the parameters of the problem are subject to uncertainty and a...
Show More
-
A Parametric Kernel Function Yielding the Best Known Iteration Bound of Interior-Point Methods for Semidefinite Optimization
Xiyao Luo,
Gang Ma,
Xiaodong Hu,
Yuqing Fu
Issue:
Volume 4, Issue 6, December 2016
Pages:
316-323
Received:
2 November 2016
Accepted:
6 December 2016
Published:
26 December 2016
Abstract: In this paper, a class of large-update primal-dual interior-point methods for semidefinite optimization based on a parametric kernel function are presented. The proposed kernel function is not only used for determining the search directions but also for measuring the distance between the given iterate and the center for the algorithms. By means of the Nesterov and Todd scaling scheme, the currently best known iteration bounds for large-update methods is established.
Abstract: In this paper, a class of large-update primal-dual interior-point methods for semidefinite optimization based on a parametric kernel function are presented. The proposed kernel function is not only used for determining the search directions but also for measuring the distance between the given iterate and the center for the algorithms. By means of ...
Show More
-
Mathematical Modelling on Blood Flow Under Atherosclerotic Condition
Issue:
Volume 4, Issue 6, December 2016
Pages:
324-329
Received:
5 December 2016
Accepted:
15 December 2016
Published:
9 January 2017
Abstract: The present study discusses the effect of stenosis on flow rate, resistance to flow and wall shear stress for different parameters. A two –layered mathematical model has been incorporated here by considering the peripheral layer as Newtonian fluid and the core layer as Bingham-plastic type non-Newtonian fluid. The numerical results are presented in graphical form.
Abstract: The present study discusses the effect of stenosis on flow rate, resistance to flow and wall shear stress for different parameters. A two –layered mathematical model has been incorporated here by considering the peripheral layer as Newtonian fluid and the core layer as Bingham-plastic type non-Newtonian fluid. The numerical results are presented in...
Show More
-
Modelling of an Extended Brutedl Algorithm for Rule Extraction
Bolanle F. Oladejo,
Rukayat Ayomide Erinfolami
Issue:
Volume 4, Issue 6, December 2016
Pages:
330-339
Received:
8 October 2016
Accepted:
22 November 2016
Published:
16 January 2017
Abstract: Complex predictive models obtain very high predictive performance; however, it is difficult to explain their complex mathematical design. Rule extraction techniques help to understand their designs by generating structures like decision list. BruteDL algorithm generates decision list from a dataset, and also addresses the overlapping rule problem of most decision list learners. However; it does not harness the power of complex predictive model. It also performs poorly with small dataset. Hence, this work aimed to create rule extraction technique by extending BruteDL and to address its poor performance with small dataset. A rule extraction technique named BruteDL-RET (Brute Decision List-Rule Extraction Technique) was modeled and implemented. A finite state automaton was used to model the technique. A functionality to generate supporting training set was included. Artificial Neural Networks (ANN) is chosen as the complex predictive model which serves as the oracle because it decides the class of each example. Decision list was generated using both the predictive model and the dataset it was trained with. The implementation was done using Java programming language. We prove that on the average BruteDL-RET is able to generate more accurate rules than BruteDL. We report on the performance of our model using dataset of UCI repository.
Abstract: Complex predictive models obtain very high predictive performance; however, it is difficult to explain their complex mathematical design. Rule extraction techniques help to understand their designs by generating structures like decision list. BruteDL algorithm generates decision list from a dataset, and also addresses the overlapping rule problem o...
Show More