[show abstract][hide abstract] ABSTRACT: Wireless mesh network is a flexible, low cost and multi-purpose networking platform with wired infrastructure connected to the internet. In WMN nodes often have a limited battery supply to use for the sending and reception of transmissions. Routing protocols over WMN are an important issue and many proposals have been addressed to efficiently manage topology information, to offer network scalability and to prolong network lifetime. Optimized Link State Routing (OLSR) is a proactive type of routing which presents the advantage of finding a route between two nodes in the network in a very short time. It can consume lot of energy resources in selecting the Multi-point Relays (MPRs) and exchanging Topology Control information. To overcome this, we present a mechanisms for the OLSR routing protocol to improve its energy performance in Wireless Mesh Networks. We propose a Minimum Battery Draining Rate Aware (MDRA-OLSR) algorithm which utilizes the
information collected by OLSR at every node in providing better network connectivity. We propose a modification in the MPR selection mechanism of OLSR protocol, based on the Willingness concept, in order to increase the network lifetime without losses of performance such as PDR, throughput etc. We consider both available energy and battery draining rate metric as a key criteria to select MPR in a set of MPRs. A comparison of an OLSR and MDRA-OLSR protocol is performed. The experiments are simulated using NS3 simulator by considering various situations such as changing speed of nodes, data rate and packet size by keeping the nodes position static and moving nodes dynamically. In this paper, we present the related works on utilization of energy as metric in routing, proposed model, simulation and discussions of the model in Wireless Mesh Networks.
13TH CONFERENCE OF FRUCT ASSOCIATION, Petrozavodsk, Russia,; 04/2013
[show abstract][hide abstract] ABSTRACT: The study involves synthesis of polypropylene grafted with glycidyl methacrylate (PP-g-GMA) using three different initiators, benzoyl peroxide, dicumyl peroxide and tertiary butyl cumyl peroxide (TBSP). Among the peroxides used, dicumyl peroxide resulted in considerable reduction of molecular weight of the resulting graft copolymer. The melting/crystallization behavior and isothermal crystallization kinetics of PP homopolymer and PP-g-GMA copolymers were studied with differential scanning calorimetry (DSC) at high undercooling (44–60°C). The results showed that the degree of crystallinity and overall crystallization rate of copolymers is greater than that of virgin PP. Among the three initiators used, TBCP exhibited lowest half crystallization time. The isothermal crystallization kinetics of the PP and copolymers was described with the Avrami equation and Sestak-Berggren (SB) equation. The Avrami exponent n of the PP and copolymers were found to be in the range 1.03 to 1.41 at high undercooling conditions employed in this study. The agreement between the values of n calculated from SB kinetics and Avrami equation is satisfactory with few exceptions. The crystallization rate of PP-g-GMA copolymer was found to be more sensitive to temperature. The isothermally crystallized samples showed a single melting peak for PP while a double peak at lower temperature was recorded for PP-g-GMA copolymer samples. The equilibrium melting point was deduced according to Hoffman-Weeks theory. The decrease of recorded for the PP modified with GMA suggests that the thermodynamic stability of the PP crystals is influenced by the chemical interactions.
[show abstract][hide abstract] ABSTRACT: In recent times Wireless Mesh Networks (WMN) have evolved as powerful networks for most commercial ap-
plications. Many contributions have been made to enhance the performance of WMN of which the enhancement of the network lifetime remains as one of the challenging area for research. IEEE standard proposed an amendment which introduced Power Save Mode (PSM) in order to increase the lifetime of WMN. It has three modes such as Active, Light Sleep and Deep Sleep. There exist a lot of literature on increasing energy efficiency by keeping node in Deep Sleep mode when it is not involved in transmission. But current Power Save Mode has some deficiency in low Packet Delivery Ratio (PDR). This paper presents Energy Aware Power Save Mode (EAPSM) which attempt to overcome the deficiency of low PDR by triggering PSM. EAPSM consist of three modules namely, remaining energy calculator, transmission mode identifier and PSM scheduler. EAPSM schedules PSM based on the constraints such as remaining energy of a node and its participation in transmission. The proposed method includes mathematical model and algorithms which gives improved performance over conventional PSM.
14th CONFERENCE OF FRUCT ASSOCIATION, Helsinki, Finland; 11/2013