Shah T.,COSMATS Institute of Information Technology |
Mustafa M.,COSMATS Institute of Information Technology |
Ahmed S.H.,COSMATS Institute of Information Technology |
Bouk S.H.,Kyungpook National University |
Kim D.,Kyungpook National University
Proceedings - 11th International Conference on Frontiers of Information Technology, FIT 2013 | Year: 2013
Stability and lifetime of Wireless Sensor Networks (WSNs) mainly depend on energy of each node in the network. Hence, it is necessary for a WSN to be energy efferent. There are different methods to preserve energy in WSNs and clustering is one of those methods. Clustering techniques divide whole network into small blocks, each having a managing node, called cluster head (CH) and rest of the nodes within that block act as members. In this paper, we propose a distributed clustering scheme, called Modified VIKOR model based Clustering (MVC) protocol. This technique uses multiple criteria i.e. residual energy, node degree, distance to the base station and average distance between a node and its neighbors, to select a cluster head. Each node shares those parameters within its transmission range and decides which CH is suitable within that region. Modified VIKOR method is used to outrank the potential nodes as CHs by considering the conflicting criteria. The realistic multi-hoping communication model is used in both, inter-cluster and intra-cluster communication, instead of single hop as in previous schemes. Simulation results show that our purposed technique performs much better than those previous methods in terms of energy efficiency, network life time, less CH deformation and control overhead. © 2013 IEEE.
Saleem S.,COSMATS Institute of Information Technology |
Saqib A.N.S.,COSMATS Institute of Information Technology |
Mujahid A.,University of Punjab |
Hanif M.,COSMATS Institute of Information Technology |
And 4 more authors.
Desalination and Water Treatment | Year: 2014
Abstract: Removal of toxic heavy metals from water matrices is an important challenge in water pollution. In this study, a solid-phase extraction method based on physical adsorption is reported for the removal of Pb(II). Two modified silica sorbents were developed by direct immobilization of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide (C4) and 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide (C6), respectively, on silica surface. Surface modification and characterization of adsorbents were confirmed by FTIR and SEM. Both the sorbents showed enhanced sorption capacity for Pb(II), however, sorbent loaded with 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide showed relatively increased removal efficiency when compared to silica loaded with 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide. Batch studies were performed to optimize different variables that influence adsorption process i.e. effect of sorbent dosage, pH, time of contact, sorbate concentration, and temperature. Langmuir, Freundlich, and Temkin isotherms were applied to study adsorption phenomenon. © 2014, Balaban Desalination Publications. All rights reserved.