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The present study investigates the significance of activation energy during chemical reactions, thermal radiations and temperature gradient of 3-D steady Magnetohydrodynamic Casson nanofluid flow (MHDCNFM) in Darcy−Forchheimer medium over an oscillating disk by using an intelligent numerical-based computing solver through the Levenberg-Marquardt backpropagation neural network scheme (LMBNNS). The adjusted Buongiorno model is utilized to develop the system of partial differential equations (PDEs) for MHDCNFM, and further, by invoking Von Karman similarity transformation, the system of governing PDEs is turned out into ordinary differential equations (ODEs). First, a data set for the magnetohydrodynamic Casson nanofluid flow model (MHDNNFM) is generated for a range of sundry parameters for the radial velocity, tangential velocity, heat distribution and concentration profile by the variations of Casson parameter, magnetic parameter, Brownian motion parameter, thermophoresis parameter, Forchheimer parameter, activation energy parameter, chemical reaction parameter, stretching parameter, porosity parameter and Schmidt number through the Lobatto IIIA technique, and after this, by applying an intelligent computing algorithm through nftool training, testing and validation steps are taken into account to find out the approximate solution for various cases. The designed solver LMBNNS is used to solve the MHDCNFM through mean squared error (MSE), regression, gradient analysis and histogram studies. [ABSTRACT FROM AUTHOR]

The present study aims to design a Levenberg-Marquardt backpropagation neural network (LMB-NN) integrated numerical computing to investigate the problem of fluid mechanics governing the flow of magnetohydrodynamics micro-polar nanofluid flow over a rotating disk (MHD-MNRD) model along with the partial slip condition. In terms of PDEs, the basic system model MHD-MNRD is transformed into a system of non-linear ODEs by applying the similarity of transformations. For MHD-MNRD scenarios, the comparative dataset of the built LMB-NN procedure is formulated with the technique of Adams numerical by variation of micro-polar parameters, Brownian motion, Lewis number, magnetic parameter, velocity slip parameter and thermophoresis parameter. To compute the approximate solution for MHD-MNRD for various scenarios, validation, testing and training procedures are carried out in accordance to adjust the networks under the backpropagation procedure in terms of the mean square error (MSE). The efficiency of the designed LMB-NN methodology is highlighted by comparative study and performance analysis based on error histograms, MSE analysis, regression and correlation. [ABSTRACT FROM AUTHOR]

The current study reveals the impact of MHD heat transfer properties of an incompressible viscous fluid were numerically solved across a continuously expanding horizontal cylinder immersed in a porous material in the existence of internal heat production/sink. The partial differential equations which govern the fluid flow with boundary constraints were converted to a collection of non-linear ODE's with the aid of similarity variables and then numerically solved by using Keller-Box approach. The components of fluid velocity, temperature, as well as friction factor, and rate of heat transfer were all calculated numerically. Graphs and tables illustrate the fluid velocity and heat transfer properties for several Prandtl numbers, and magnetic parameters. The main goal of the current findings is to examine how the magnetic field M , Pr , and the heat absorption/generation factor Q influence the velocity and temperature gradients along a stretching cylinder. It is projected that the rise in the curvature parameter and the porosity factor would contribute to the enhancement of the temperature gradient in the boundary layer area around the cylinder. [ABSTRACT FROM AUTHOR]

This article presents, for the first time, a comparative analysis of two different solution methodologies for the numerical investigation of flow and thermal behavior of Casson fluid through a channel having linearly extending lower wall while the upper wall is kept at rest. MHD Casson fluid boundary layer flow is supposed to be steady, laminar, viscous, and incompressible. We have taken into account the mixed convection effects, whereas the usual no slip condition has been imposed on both walls. The Navier–Stokes equations for the proposed model have been converted into nonlinear and coupled system of ordinary differential equations (ODEs) by employing similarity variables, which are then solved by using the differential transform method (DTM) and the quasi‐linearization method (QLM). We note that the quasi‐linearization approach is better than the DTM, as the latter becomes inappropriate for the increasing values of the parameters involved. Moreover, the variation of the different parameters for velocity and temperature profiles has been analyzed graphically. [ABSTRACT FROM AUTHOR]

In this work, the influence of thermal energy in term of heat source, thermal radiation and chemical reaction on magneto hydrodynamic Casson fluid flow model (MHD-CFM) over a nonlinear slanted extending surface with slip velocity in a Forchheimer permeable medium is numerically studied using the Levenberg Marquardt methodology with backpropagated learning mechanism. It is valuable to evaluate the flow of Cason fluids based on materials (such as drilling muds, clay coatings, various suspensions and certain lubricating oils, polymeric melts, and a wide range of colloids) in the occurrence of heat transfer. Using efficient data, PDEs of (MHD-CFM) were converted to ordinary differential equations. These obtained non-linear ODEs are then rectified using the computational power of the Lobatto IIIA approach to obtain a dataset of Levenberg Marquardt algorithm based trained neural networks (LMA-TNN) for six scenarios of this presented model, which were graphically represented using nftool to obtain regression, efficiency, fit curve, error bars, and trained state analysis. The velocity, temperature, and concentration profiles were computed, and the findings were presented. Additionally, the skin friction coefficient, Nusselt number, & local Sherwood number are explored. The graphs show that when values of radiation parameter and the Forchheimer porous media parameter increase, the temperature of the plate drops. In the existence of a chemical process and a high Schmidt number, the concentration drops. The accuracy achieved in terms of relative error demonstrates the validity and significance of the solution process. [ABSTRACT FROM AUTHOR]

In present research manuscript, analysis is presented for the influences of heat transition in a bodewadt flow over a penetrable disk numerically. Estimation parameters in current mathematical flow model include magnetic field parameter (0.1 ≤ M ≤ 1.2) , wall suction (1.7 ≤ A ≤ 6.7) , prandtl number (0.2 ≤ Pr ≤ 5.0) , heat generation/absorption (- 0.9 ≤ Q ≤ 3.6) , eckert number (0 ≤ E c ≤ 1.2) , variable viscosity (- 100 ≤ θ e ≤ 100) and thermal conductivity (0 ≤ ε ≤ 4.1). The repercussions of joule heating, wall suction, heat generation & absorption, magnetic field, viscous dissipation accompanying with variable characteristics of the fluid are also examined as well. Kinetics of viscous fluid with variable characteristics of fluid having solid body rotation over a permeable disk (having cylindrical geometry) are analyzed. We transformed the governing equations of heat transfer (accompanied by variable properties) and fluid motion in to self-similar non-dimensional differential equations by using the Von-Karman variables which are then further analyzed numerically by utilizing Adams Bashforth method. For a physical insight, results are manifested to scrutinize the behavior of velocity and temperature profiles for different emerging parameters graphically. Moreover, the values of nusselt number & skin friction co-efficient are also computed and physically explicated for the assorted parameters. Outcomes of current investigations are compared with prior work, to ensure the authenticity of the numerical method, and strong agreement is noted. [ABSTRACT FROM AUTHOR]

The magnetohydrodynamics (MHD) viscous Jeffrey heat transport flow past a permeable extending sheet is analyzed. The Alumina ( A l 2 O 3 ) is chosen as nanoparticles immersed in sodium alginate ( SA ) as the based fluid. The effect of heat generation, Ohmic heating and viscous dissipation are also being investigated adopting Tiwari and Das model. The adequate similarity transformation is used to convert the governing equations to non-linear of higher-order ordinary differential equations (ODEs). The numerical solution of the transformed ODEs is accomplished using a finite-difference technique. The results are described in graphs according to selected parameters' values provided. The flow velocity reductions when the porosity parameter is augmented. The thermal distribution is affected by the presence of Pr , M , β , γ ∗ , δ ∗ and ϕ . Deborah number and the volume fraction of nanoparticles affect the skin friction coefficient in opposite ways. A higher volume percentage of nanoparticles and a higher Deborah number are both shown to boost the rate of heat transfer. These findings suggest that the concentration of nanoparticles can be used to manipulate heat transport and nanofluid motions. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the solution of the magneto hydrodynamics (MHD) thermal boundary layer flow of Casson liquid over a penetrable extending wedge with ohmic heating and convective boundary condition (BC). Important applications of such flows and condition include the MHD pump, radiation therapy, MHD generator, soil mechanics, melt spinning process, thermal insulation and many others. Practical applications of convective BC are often encountered in laser damage or laser processing. The problem is non dimensionalized and computational solutions are achieved for the governing nonlinear coupled ordinary differential equations (PDEs) by using homotopy analysis method (HAM) and influence of various emerging parameters on momentum and temperature field are examined. A table containing computational data for the wall shear stress f ′ ′ (0) and local Nusselt - θ ′ (0) number is also provided. Major findings/objectives of the present study are: an increasing in Casson fluid parameter δ decreases velocity when wedge stretches faster than free stream velocity for R = 2. However, velocity increases for R = 0.1 case. Temperature velocity decreases for R = 2 or R = 0.1 cases for δ escalations. Enhancing B i for convective heat transfer increases the momentum and thermal boundary layer thickness in the presence of suction C. Computational outcomes for velocity, drag force, temperature velocity and heat transfer rate are discussed through tables numerically. Results are verified with varied choices of suction parameter C. It is noted that the convective parameter magnified the heat transfer rate. [ABSTRACT FROM AUTHOR]

Summary: Hybrid nanoliquids comprise of better physical strength, mechanical resistance, thermal conductivity, and chemical stability as equated to individual nanoliquids. The present work investigates the MHD laminar flow, containing hybrid nanoparticles, with heat transfer phenomenon over a stretching sheet immersed in a porous medium. The effect of induced magnetic field has also been taken into account. The flow model PDEs are rehabilitated into ordinary ones using a persuasive tool of similarity variables. The analogous system of dimensionless equations alongside the boundary conditions is numerically treated with the Successive‐Over‐Relaxation (SOR) technique. Flow and heat transfer aspects of both pure and hybrid nanofluids are examined for the preeminent parameters. Our outcomes are associated with the previously accomplished experimental and numerical results, and found to be in a good agreement with them. As a major outcome of the study, it has been noted that, apart from their well‐reported thermal characteristics, hybrid nanofluids are capable of raising the shear stress to remarkably higher levels (upto 57% in some cases). Therefore, such fluids must be used with caution in applications where a control on the shear stress is required. [ABSTRACT FROM AUTHOR]

An emerging definition of the fractal-fractional operator has been used in this study for the modeling of Casson fluid flow. The magnetohydrodynamics flow of Casson fluid has cogent in a channel where the motion of the upper plate generates the flow while the lower plate is at a static position. The proposed model is non-dimensionalized using the Pi-Buckingham theorem to reduce the complexity in solving the model and computation time. The non-dimensional fractal-fractional model with the power-law kernel has been solved through the Laplace transform technique. The Mathcad software has been used for illustration of the influence of various parameters, i.e., Hartman number, fractal, fractional, and Casson fluid parameters on the velocity of fluid flow. Through graphs and tables, the results have been implemented and it is shown that the boundary conditions are fully satisfied. The results reveal that the flow velocity is decreasing with the increasing values of the Hartman number and is increasing with the increasing values of the Casson fluid parameter. The findings of the fractal-fractional model have elucidated that the memory effect of the flow model has higher quality than the simple fractional and classical models. Furthermore, to show the validity of the obtained closed-form solutions, special cases have been obtained which are in agreement with the already published solutions. [ABSTRACT FROM AUTHOR]

The objective of this work is to analyze the impact of magneto-hydrodynamics flow across a stretching layer in the existing magnetic sector. The classifying boundary layer equations are converted to a set of non-linear equations by taking advantage of similarity structures. The transformed scheme is mathematically resolved by the homotopy analysis method. Results are measured numerically and plotted graphically for velocity and temperature distribution. Furthermore, flow and heat transfer effects for different physical parameters such as the stretching parameter, mixed convection parameter, magnetic parameter, heat generation coefficient, and Prandtl number are analyzed. Some physical effects reveal that an increase in the Hartmann number raises the fluid's boundary layer that shows the reverse phenomena of Lorentz force because the speed of the free stream transcends the stretching surface. Upon verifying the homology of the current study with some past investigations, a good harmony is revealed. The velocity of the fluid flow was initially considered to be an increasing function of heat generation, buoyancy parameter, and magnetic field strength, but it later revealed as a decreasing function of the Prandtl number. [ABSTRACT FROM AUTHOR]

An analysis is carried out for the steady free convective incompressible electrically conducting Jeffry fluid flow over a stretching surface. In addition, the presence of uniform heat source and first order chemical reaction enhance the heat and mass transfer properties of non-Newtonian fluid. Suitable self-similar transformations are used for the transformation of complex PDEs to nonlinear ODEs. Semi-analytical approach like Adomian Decomposition Method (ADM) is employed for this transformed governing equation to get approximate analytical solution. Further, the behavior of characterizing parameters is presented through graphs. The validation of the present result is obtained with an earlier established result in particular case. However, the major outcomes are; both the interaction parameter and Hartmann number favors in to enhance the velocity profiles whereas the it is interesting to see that, increasing interaction parameter for higher value of Hartmann number retards the fluid temperature but reverse effect is rendered for lower value. [ABSTRACT FROM AUTHOR]

The present research article is directed to study the heat and mass transference analysis of an incompressible Newtonian viscous fluid. The unsteady MHD natural convection flow over an infinite vertical plate with time dependent arbitrary shear stresses has been investigated. In heat and mass transfer analysis the chemical molecular diffusivity effects have been studied. Moreover, the infinite vertical plate is subjected to the phenomenon of exponential heating. For this study, we formulated the problem into three governing equations along with their corresponding initial and boundary conditions. The Laplace transform method has been used to gain the exact analytical solutions to the problem. Special cases of the obtained solutions are investigated. It is noticed that some well-known results from the published literature are achieved from these special cases. Finally, different physical parameters' responses are investigated graphically through Mathcad software. [ABSTRACT FROM AUTHOR]

The idea of fractional derivatives is applied to several problems of viscoelastic fluid. However, most of these problems (fluid problems), were studied analytically using different integral transform techniques, as most of these problems are linear. The idea of the above fractional derivatives is rarely applied to fluid problems governed by nonlinear partial differential equations. Most importantly, in the nonlinear problems, either the fractional models are developed by artificial replacement of the classical derivatives with fractional derivatives or simple classical problems (without developing the fractional model even using artificial replacement) are solved. These problems were mostly solved for steady-state fluid problems. In the present article, studied unsteady nonlinear non- Newtonian fluid problem (Cattaneo-Friedrich Maxwell (CFM) model) and the fractional model are developed starting from the fractional constitutive equations to the fractional governing equations; in other words, the artificial replacement of the classical derivatives with fractional derivatives is not done, but in details, the fractional problem is modeled from the fractional constitutive equations. More exactly two-dimensional magnetic resistive flow in a porous medium of fractional Maxwell fluid (FMF) over an inclined plate with variable velocity and the temperature is studied. The Caputo time-fractional derivative model (CFM) is used in the governing equations. The proposed model is numerically solved via finite difference method (FDM) along with L1-scheme for discretization. The numerical results are presented in various figures. These results indicated that the fractional parameters significantly affect the temperature and velocity fields. It is noticed that the temperature field increased with an increase in the fractional parameter. Whereas, the effect of fractional parameters is opposite on the velocity field the plate. Moreover, the velocity field retarded with strengthening in the magnetic parameter due to enhancement in Lorentz force. However, this effect reverses in the case of the temperature profile. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to evaluate the exact solution of the unsteady flow of a generalized Brinkman type fluid under the effect of MHD in a channel. The classical Brinkman model reduced to non-dimensional form by using appropriate dimensionless variables. Furthermore, the non-dimensional Brinkman model is transformed to a generalize Brinkman model with Caputo-Fabrizio fractional derivative. The dimensionless Brinkman model has been solved with applicable conditions by integral transforms techniques that is Fourier and Laplace. The effect of different physical parameters and fractional order on fluid velocity and shear stress are illustrated graphically. Moreover, through this recent work, the recovery of classical Brinkman type fluid is possible through graphs. [ABSTRACT FROM AUTHOR]

In this analysis, we introduced heat convective aspects of stagnation point movement of a magnetohydrodynamic (MHD) stream on a nonlinear oscillating plane with the impacts of velocity and heat slips with variable heat reservoir. By using some appropriate transformations, the governing differential equations are switched into an ordinary differential equation. The semianalytics technique called Homotpy Analysis Method (HAM) has been applied to evaluate the ordinary differential equations. For convergence achievement, a numerical method BVPh2-midpoint method is also applied and an outstanding agreement is found. The impacts of the governing constraints on flow, motion, and temperature distributions are investigated in detail. We observed that the temperature distribution increases with nonlinear heat reservoir parameter. Our results, in some limiting situations, matched well with previously published results, which approve that our obtained results are correct. [ABSTRACT FROM AUTHOR]

The mass and heat transfer magnetohydrodynamic (MHD) flows have a substantial use in heat exchangers, electromagnetic casting, X-rays, the cooling of nuclear reactors, mass transportation, magnetic drug treatment, energy systems, fiber coating, etc. The present work numerically explores the mass and heat transportation flow of MHD micropolar fluid with the consideration of a chemical reaction. The flow is taken between the walls of a permeable channel. The quasi-linearization technique is utilized to solve the complex dynamical coupled and nonlinear differential equations. The consequences of the preeminent parameters are portrayed via graphs and tables. A tabular and graphical comparison evidently reveals a correlation of our results with the existing ones. A strong deceleration is found in the concentration due to the effect of a chemical reaction. Furthermore, the impact of the magnetic field force is to devaluate the mass and heat transfer rates not only at the lower but at the upper channel walls, likewise. [ABSTRACT FROM AUTHOR]

The technique of Levenberg–Marquardt back propagation with neural networks (TLMB-NN) was used in this research article to investigate the heat transfer of Maxwell base fluid flow of nanomaterials (HTM-BFN) with MHD over vertical moving surfaces. In this study, the effects of thermal energy, concentration, and Brownian motion are also employed. Moreover, the impacts of a heat-absorbing fluid with viscous dissipation and radiation have been explored. To simplify the governing equations from a stiff to a simple system of non-linear ODEs, we exploited the efficacy of suitable similarity transformation mechanism. Through applicability of state-of-the-art Adams numerical technique, a set of data for suggested (TLMB-NN) is generated for several situations (scenarios) by changing parameters, such as the Thermophoresis factor Nt, Hartmann number M, Eckert number Ec, concentration Grashoff parameter Gc, Prandtl number Pr, Lewis number Le, thermal Grashof number GT, and Brownian motion factor Nb. The estimate solution of different instances has validated using the (TLMB-NN) training, testing, and validation method, and the recommended model was compared for excellence. Following that, regression analysis, mean square error, and histogram explorations are used to validate the suggested (TLMB-NN). The proposed technique is distinguished based on the proximity of the proposed and reference findings, with an accuracy level ranging from 10−9 to 10−10. [ABSTRACT FROM AUTHOR]

The current analysis deals with radiative aspects of magnetohydrodynamic boundary layer flow with heat mass transfer features on electrically conductive Williamson nanofluid by a stretching surface. The impact of variable thickness and thermal conductivity characteristics in view of melting heat flow are examined. The mathematical formulation of Williamson nanofluid flow is based on boundary layer theory pioneered by Prandtl. The boundary layer nanofluid flow idea yields a constitutive flow laws of partial differential equations (PDEs) are made dimensionless and then reduce to ordinary nonlinear differential equations (ODEs) versus transformation technique. A built-in numerical algorithm bvp4c in Mathematica software is employed for nonlinear systems computation. Considerable features of dimensionless parameters are reviewed via graphical description. A comparison with another homotopic approach (HAM) as a limiting case and an excellent agreement perceived. [ABSTRACT FROM AUTHOR]

In this paper, the rate of heat transfer of the steady MHD stagnation point flow of Casson fluid on the shrinking/stretching surface has been investigated with the effect of thermal radiation and viscous dissipation. The governing partial differential equations are first transformed into the ordinary (similarity) differential equations. The obtained system of equations is converted from boundary value problems (BVPs) to initial value problems (IVPs) with the help of the shooting method which then solved by the RK method with help of maple software. Furthermore, the three-stage Labatto III-A method is applied to perform stability analysis with the help of a bvp4c solver in MATLAB. Current outcomes contradict numerically with published results and found inastounding agreements. The results reveal that there exist dual solutions in both shrinking and stretching surfaces. Furthermore, the temperature increases when thermal radiation, Eckert number, and magnetic number are increased. Signs of the smallest eigenvalue reveal that only the first solution is stable and can be realizable physically. [ABSTRACT FROM AUTHOR]

In this analysis, we aim to examine the heat transfer and flow characteristics of a copper-aluminum/water hybrid nanofluid in the presence of viscous dissipation, magnetohydrodynamic (MHD), and porous medium effect over the shrinking sheet. The governing equations of the fluid model have been acquired by employment of the model of Tiwari and Das, with additional properties of the hybrid nanofluid. The system of partial differential equations (PDEs) has been converted into ordinary differential equations (ODEs) by adopting the exponential similarity transformation. Similarity transformation is an essential class of phenomenon where the symmetry of the scale helps to reduce the number of independent variables. Note that ODE solutions demonstrate the PDEs symmetrical behavior for the velocity and temperature profiles. With BVP4C solver in the MATLAB program, the system of resulting equations has been solved. We have compared the present results with the published results and found in excellent agreements. The findings of the analysis are also displayed and discussed in depth graphically and numerically. It is discovered that two solutions occur in definite ranges of suction and magnetic parameters. Dual (no) similarity solutions can be found in the range of S c ≤ S   and   M c ≤ M ( S c > S   and   M c > M ). By performing stability analysis, the smallest values of eigenvalue are obtained, suggesting that a stable solution is the first one. Furthermore, the graph of the smallest eigenvalue shows symmetrical behavior. By enhancing the Eckert number values the temperature of the fluid is raised. [ABSTRACT FROM AUTHOR]

In this study, first-order slip effect with viscous dissipation and thermal radiation in micropolar fluid on a linear shrinking sheet is considered. Mathematical formulations of the governing equations of the problem have been derived by employing the fundamental laws of conservations which then converted into highly non-linear coupled partial differential equations (PDEs) of boundary layers. Linear transformations are employed to change PDEs into non-dimensional ordinary differential equations (ODEs). The solutions of the resultant ODEs have been obtained by using of numerical method which is presented in the form of shootlib package in MAPLE 2018. The results reveal that there is more than one solution depending upon the values of suction and material parameters. The ranges of dual solutions are S   ≥   S c i , i   =   0 ,   1 ,   2 and no solution is S   <   S c i where S c i is the critical values of S. Critical values have been obtained in the presence of dual solutions and the stability analysis is carried out to identify more stable solutions. Variations of numerous parameters have been also examined by giving tables and graphs. The numerical values have been obtained for the skin friction and local Nusselt number and presented graphically. Further, it is observed that the temperature and thickness of the thermal boundary layer increase when thermal radiation parameter is increased in both solutions. In addition, it is also noticed that the fluid velocity increases in the case of strong magnetic field effect in the second solution. [ABSTRACT FROM AUTHOR]

In this paper, the MHD flow of a micropolar nanofluid on an exponential sheet in an Extended-Darcy-Forchheimer porous medium have been considered. Buongiorno's model is considered in order to formulate a mathematical model with different boundary conditions. The governing partial differential equations (PDEs) of the nanofluid flow are changed into a third order non-linear quasi-ordinary differential equation (ODE), using the pseudo-similarity variable. The resultant ODEs of the boundary value problems (BVPs) are renewed into initial value problems (IVPs) using a shooting method, and then the IVPs are solved by a fourth order Runge-Kutta (RK) method. The effects of various physical parameters on the profiles of velocity, temperature, microrotation velocity, concentration, skin friction, couple stress coefficients, heat, and concentration transfer are demonstrated graphically. The results reveal that triple solutions appear when S ≥ 2.0337 for K = 0.1 and S ≥ 2.7148 for K = 0.2 . A stability analysis has been performed to show the stability of the solutions; only the first solution is stable and physically possible, whereas the remaining two solutions are not stable. [ABSTRACT FROM AUTHOR]

The current work will describe the entropy generation in an unsteady magnetohydrodynamic (MHD) flow with a combined influence of mass and heat transfer through a porous medium. It will consider the flow in the XY plane and the plate with isothermal and ramped wall temperature. The wall shear stress is also considered. The influences of different pertinent parameters on velocity, the Bejan number and on the total entropy generation number are reported graphically. Entropy generation in the fluid is controlled and reduced on the boundary by using wall shear stress. It is observed in this paper that by taking suitable values of pertinent parameters, the energy losses in the system can be minimized. These parameters are the Schmitt number, mass diffusion parameter, Prandtl number, Grashof number, magnetic parameter and modified Grashof number. These results will play an important role in the heat flow of uncertainty and must, therefore, be controlled and managed effectively. [ABSTRACT FROM AUTHOR]