Faculty Publications
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Item Determination of task scheduling mechanism using computational intelligence in Cloud Computing(Institute of Electrical and Electronics Engineers Inc., 2016) George, N.; Chandrasekaran, K.; Binu, A.Cloud Computing delivers computational services through the internet. The services availed can vary according to the user requirements. The services are basically provided using virtualization technique. One of the services that are provided is the computational services for the client tasks. The client provides the Service Provider with various sized tasks that need to be executed. The execution of tasks is done using the resources present within the Provider of the services. The service provider checks for available resources, and allocates the jobs to these resources in such a manner as to minimize execution time, and various other factors that affect the performance of the Cloud. The process of allocating resources to the tasks is known as scheduling, and various scheduling mechanisms are present. A single scheduling strategy may not be always optimal in performing scheduling. In this paper, an improved mechanism for choosing the scheduling strategy is explained, which aims at addressing the problems associated with choosing the right scheduling mechanism according to the previously exhibited performances. Experimental results demonstrate the importance of using such a mechanism in selecting the right scheduling strategy. © 2015 IEEE.Item An objective study on improvement of task scheduling mechanism using computational intelligence in cloud computing(Institute of Electrical and Electronics Engineers Inc., 2016) George, N.; Chandrasekaran, K.; Binu, A.Cloud Computing facilitates delivery of various types of computational services through the internet. These services can be availed according to the user demand. The resource scarcity problems within the Service Providers are met using Virtualization technique, which allows scalability of resources and thereby helps to meet the client requirements. Allocation of resources to client tasks is an issue that is being addressed for a long time. Due to the increased complexity in the area, there has not yet been a perfect scheduling mechanism. Practices have been done profusely in order to find solutions for scheduling that nears optimality. A single scheduling mechanism may not always give the expected outcome. The task scheduling mechanisms are designed in a manner as to optimize some metrics related to the Cloud. This paper overviews various literature associated with task scheduling and resource scheduling in Cloud Computing. An examination of the techniques is done and a proposal is made, which will allow to further improve the scheduling mechanism. © 2015 IEEE.Item Optimization-Aware scheduling in cloud computing(Association for Computing Machinery acmhelp@acm.org, 2016) Binu, A.; George, N.; Chandrasekaran, K.Cloud computing allows delivery of computational resources via internet. Some of the computational resources include signals, codes and physical resources. Cloud users require computational resources for execution of their tasks. The computational elements, when thoroughly assigned to the cloud users according to requirement facilitate an efficient scheduling mechanism. The efficiency is dependent on the parameters chosen to promote the assignment of task to resources. Here, computational cost is chosen as the optimization factor, and the solution with the least cost is selected as the best assignment. A Cuckoo Search inspired technique is used, and task assignment to resources is done by validating the solution with the least value of cost. © 2016 ACM.Item Vibro-acoustic behaviour of functionally graded graphene reinforced polymer nanocomposites(American Institute of Physics Inc. subs@aip.org, 2020) Pious, D.; Jacob, J.; George, N.; Bhagat, V.; Chacko, T.; Jeyaraj, P.This study conducts an investigation into the vibro-acoustic behavior of polymer nano composites reinforced with functionally graded graphene. The numerical analysis is conducted using both finite element method and Rayleigh integral. Free and forced vibration characteristics are conducted to understand the sound characteristics in depth. The influence of various parameters such as type of functional grading, loading and boundary conditions are also observed. Results shows that natural frequency of a structure is heavily dependent on the type of functional grading of the structure, while the mode shapes are observed to be impervious to these changes. The type of functional grading is also seen to influence the resonant amplitude of vibration and acoustic response. This influence is duly produced in the bandwise calculation of sound power which suggests that FG-X distribution of graphene is to be used for lower frequency levels. © 2020 Author(s).Item Buckling of non-uniformly heated isotropic beam: Experimental and theoretical investigations(Elsevier Ltd, 2016) George, N.; Jeyaraj, P.; Murigendrappa, S.M.Influence of non-uniform heating on critical buckling temperature of an aluminium beam has been investigated experimentally with the help of a novel experimental set-up developed in-house. Non-linear finite element analysis, considering the initial geometric imperfection, has been carried out to compare the experimentally obtained typical load-deflection curve. The linear critical buckling temperature predicted numerically are validated with analytical solutions. Experimental results revealed that critical buckling temperature of the non-uniformly heated beam greatly differs from the uniformly heated beam. It is also observed that the location of heat source and resulting non-uniform temperature variation influences the critical buckling temperature significantly. © 2016 Elsevier LtdItem Buckling and free vibration of nonuniformly heated functionally graded carbon nanotube reinforced polymer composite plate(World Scientific Publishing Co. Pte Ltd wspc@wspc.com.sg, 2017) George, N.; Jeyaraj, P.; Murigendrappa, S.M.Buckling and free vibration behavior of functionally graded carbon nanotube reinforced polymer composite plate subjected to nonuniform temperature fields have been investigated using finite element approach. The effective material constants of the plate are obtained using the extended rule of mixture along with efficiency parameters of the carbon nanotube (to include geometry-dependent material properties). Influence of boundary conditions, aspect ratio, functional grading of the carbon nanotube, nonuniform thermal loading on thermal buckling and free vibration behavior of the heated plate are analyzed. It is observed that temperature fields and functional grading are influenced on the critical buckling temperature of the plates. Further, nature of functional grading showed significant change in buckling mode shapes irrespective of the boundary conditions. The first few natural frequencies of the plate under thermal load decreases as the temperature increases and they are influenced significantly by the nature of temperature field. Variations in free vibration mode shapes of the square plates found with not significant change as temperature increases. However, free vibration modes of the rectangular plates are sensitive to the nature of temperature field whenever there is a free edge associated with the boundary condition. Influence of functional grading on the free vibration mode shapes is not significant in contrast with the free vibration natural frequencies. The magnitude of free vibration natural frequencies of functional grade-X type carbon nanotube reinforcement showed higher in comparison with other two types of reinforcements considered here. © 2017 World Scientific Publishing Company.Item Vibro-acoustic behavior of functionally graded carbon nanotube reinforced polymer nanocomposite plates(SAGE Publications Ltd info@sagepub.co.uk, 2018) George, N.; Jeyaraj, P.; Murigendrappa, S.M.; Mailan Chinnapandi, M.C.This paper presents the numerical investigation results carried out on vibro-acoustic behavior of functionally graded carbon nanotube reinforced polymer nanocomposite plate using combined finite element method and Rayleigh integral. Parameter studies are carried out to analyze the in?uence of nature of functional grading, loading of carbon nanotube, and structural boundary conditions on free and forced vibration and sound radiation characteristics in detail. It is found that natural frequencies are significantly in?uenced by the nature of functional grading while the mode shapes are insensitive. The resonant amplitude of vibration and acoustic response are significantly in?uenced with the nature of different functional grading. This re?ects in the bandwise calculation of sound power also which recommends the carbon nanotube functional grading with X distribution along the thickness direction for lower frequency level. Similar variation in vibro-acoustic response has been observed with increase in the carbon nanotube loading also. © 2016, IMechE 2016.Item Nonuniform Heat Effects on Buckling of Laminated Composite Beam: Experimental Investigations(World Scientific Publishing Co. Pte Ltd wspc@wspc.com.sg, 2018) George, N.; Jeyaraj, P.The influence of nonuniform heating on the critical buckling temperature of laminated glass-epoxy composite beam has been investigated experimentally with the help of a novel experimental setup. The beam is numerically investigated using nonlinear finite element analysis. An initial geometric imperfection is introduced to the modeled geometry in numerical technique to have an experimental-numerical comparison of temperature-deflection plot. The results indicate that the critical buckling temperature of a uniformly heated beam has a significant difference in comparison to the nonuniformly heated beam and it depends on the heating source location and the resulting temperature distribution along the length direction of the beam. © 2018 World Scientific Publishing Company.Item Thermal buckling and vibro-acoustic behaviour of functionally graded graphene polymer layered composites subjected to in-plane temperature variance(SAGE Publications Ltd, 2022) John, B.O.; Hassan, F.U.; George, N.; Chacko, T.; Bhagat, V.S.; Jeyaraj, J.; Kiran Kumar Reddy, R.The current study reports the thermal buckling, vibration and acoustic characteristics of functionally graded graphene polymer layer composite plates subjected to the in-plane temperature variance. The macroscopic properties of the composites are evaluated using the modified rule of mixtures to compute the layer-wise properties of an functionally graded graphene polymer layer composite plate. The critical buckling temperature is computed and compared for various functional gradings, boundary conditions and in-plane temperature variances. The in-plane temperature variance showed a major impact on the critical thermal buckling temperature and respective mode shapes. The vibro-acoustic behaviour of the functionally graded graphene polymer layer composite plate is investigated and documented keeping critical buckling temperature as a function. With an increase in thermal load and the nature of in-plane temperature variance, the vibro-acoustic results showed significant difference in velocity and acoustic response. For functionally graded graphene polymer layer composite plate with one free edge, the difference was statistically significant as indicated by an octave band plot. We conclude that the portion of the functionally graded graphene polymer layer composite plate that is subjected to the higher temperature in an in-plane temperature variance, as well as the nature of the boundary conditions may exacerbate the effect of in-plane temperature variance and are crucial in predicting vibro-acoustic characteristics. © IMechE 2022.Item Numerical Analysis on Vibro-Acoustic Behavior of Honeycomb Core Sandwich Structure with FG-CNT-Reinforced Polymer Composite Facings(Institute for Ionics, 2022) Bhagat, V.S.; George, N.; Arunkumar, M.P.; Jeyaraj, J.; Mailan Chinnapandi, M.C.L.Numerical studies carried out on the vibro-acoustic characteristics of an aluminum honeycomb core sandwich structure with functionally graded carbon nanotube polymer composite facings are presented. The layer-by-layer technique is used to model the structure by finding the equivalent elastic properties. From the vibration response, the acoustic characteristic of the honeycomb structure is found by using kinematic continuity between structural velocity and particle velocity at the surface. Forced vibration response of a hexagonal honeycomb sandwich structure is calculated experimentally, and results are compared with the proposed numerical method. Further, the result reveals that the FG-VΛ structure has better vibro-acoustic characteristics rather than FG-XX which gives better acoustic properties when it is considered as a plate without sandwich construction. © 2021, Shiraz University.