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Hybrid Metaheuristic Algorithm for Real Time
        
        The  assignments  of  real  time  tasks  to  heterogeneous  multiprocessors  in  real  time  applications  are  very  difficult  in 
scenarios that require high performance. The main problem in the heterogeneous multiprocessor system  is task assignment to 
the processors because the execution time for each task varies from one processor to another. Hence, the problem of finding a 
solution  for  task  assignment  to  heterogeneous processor without  exceeding  the  processors  capacity  in  general  is  an  NP  hard 
problem. In  order  to  meet  the  constraints  in  real  time  systems,  a  Hybrid  Max-Min  Ant colony  optimization  algorithm  (H-
MMAS) is  proposed in  this  paper.  Max-Min  Ant  System  (MMAS) is  extended  with  a  local  search  heuristic  to  improve  task 
assignment  solution.  The  Local  Search  has  resulted  in  maximizing  the  number  of  tasks  assigned  as  well  as  minimizing  the 
energy  consumption.  The  performance  of  the  proposed  algorithm  H-MMAS  is  compared  with  the  Modified Binary  Particle 
Swarm Optimization algorithm (BPSO), Ant Colony Optimization (ACO), MMAS algorithms in terms of the average number of 
task assigned, normalized energy consumption, quality of solution and average Central Processing Unit (CPU) time. From the 
experimental  results,  the  proposed  algorithm  has  outperformed  MMAS,  Modified  BPSO  and  ACO  for  consistency  matrix.  In 
case  of  inconsistency  matrix  H-MMAS  performed  better  than  Modified  BPSO,  similar  to  ACO and  MMAS,  but  there  is  an 
improvement in the normalized energy consumption.    
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[15] Wu J., Liu X., Shu J., Li Y., and Liu K., Independent Task Assignment of Space Warfare Based on MAS and ACO, Journal of Information and Computational Science, vol. 10, no. 12, pp. 3861-3867, 2013. Poongothai Marimuthu is currently an Assistant Professor (Senior Grade) in the Department of Electronics and Communication Engineering, Coimbatore Institute of Technology, Coimbatore 641014 India. Her research areas includes Scheduling in Real-time systems, energy efficient computing systems, low power design and power management of energy harvesting real-time embedded system. Rajeswari Arumugam is currently a Professor and Head of Department of Electronics and Communication Engineering, Coimbatore Institute of Technology, Coimbatore 641014 India. Her areas of interest include wireless communication, signal processing. Jabar Ali is currently doing his M.E. (Communication Engineering) in Department of Electronics and Communication Engineering, Coimbatore Institute of Technology, Coimbatore 641014, India. He completed his B.E. in Electronics and Communication Engineering in Mepco Schlenk Engineering College, Sivakasi, India. His areas of interest include Scheduling in real-time embedded systems and computer networks.
