Mobile Ad-hoc network (MANET) is an infrastructure-less and dynamic network. Routing in such a network is a challenge due to the mobility of its nodes. Multipath routing protocols try to improve the performance by fin...Mobile Ad-hoc network (MANET) is an infrastructure-less and dynamic network. Routing in such a network is a challenge due to the mobility of its nodes. Multipath routing protocols try to improve the performance by finding more than one path towards the destination which could be kept as alternatives should the main path breaks. Stability-based Partially Disjoint AOMDV (SPDA) protocol has been proposed to tackle problems resulted from the very dynamic topology of MANETs. SPDA finds partially disjoint paths that are more stable than the maximally disjoint ones in order to increase paths lifetime as well as the availability of such multipaths. When choosing partially disjoint paths, SPDA does not take into consideration the number of hops of each path. Moreover, SPDA transmits packets over the shortest path until it becomes invalid before it tries to utilize other alternative paths. In this paper we improve SPDA by adding the number of nodes each path passes through to the selection criteria. In the Improved SPDA (ISPDA), the available alternative paths have been utilized to transmit packets in parallel. We compare the SPDA and ISPDA regarding the throughput and delay. Results show the superiority of ISPDA over the original one.展开更多
Mobile Ad-hoc Network (MANET) consists of mobile nodes that are connected via very dynamic multi-hop channels. Routing in MANET is a challenging task that has received great attention from researchers. In this paper w...Mobile Ad-hoc Network (MANET) consists of mobile nodes that are connected via very dynamic multi-hop channels. Routing in MANET is a challenging task that has received great attention from researchers. In this paper we present Maximally Spatial Disjoint Multipath routing protocol (MSDM) which is a modification of AOMDV protocol. MSDM finds paths which are spatially separated and maximally disjointed. We think that sending various packets over spatially disjointed paths reduces the probability of collision occurrence and allows concurrent transmission over the set of different selected paths. Performance comparison of MSDM and AOMDV using GloMoSim simulator shows that MSDM is able to achieve a considerable improvement regarding some performance metrics such as delay, routing packets overhead, and network throughput.展开更多
Content Based Image Retrieval (CBIR) is a technique in which images are indexed based on their visual contents and retrieving is only based upon these indexed images contents. Among the visual contents to describe the...Content Based Image Retrieval (CBIR) is a technique in which images are indexed based on their visual contents and retrieving is only based upon these indexed images contents. Among the visual contents to describe the image details is shape. Shape of object, is considered as the most important distinguishable feature which living things can easily recognize, which is also a fact while this line is being written, and large efforts are currently underway in describing image contents by their shapes. Inspired by the core foundation of quantum mechanics, a new easy shape representation for content based image retrieval is proposed by borrowing the concept of quantum superposition into the basis of distance histogram. Results show better retrieval accuracy of the proposed method when compared with distance histogram.展开更多
文摘Mobile Ad-hoc network (MANET) is an infrastructure-less and dynamic network. Routing in such a network is a challenge due to the mobility of its nodes. Multipath routing protocols try to improve the performance by finding more than one path towards the destination which could be kept as alternatives should the main path breaks. Stability-based Partially Disjoint AOMDV (SPDA) protocol has been proposed to tackle problems resulted from the very dynamic topology of MANETs. SPDA finds partially disjoint paths that are more stable than the maximally disjoint ones in order to increase paths lifetime as well as the availability of such multipaths. When choosing partially disjoint paths, SPDA does not take into consideration the number of hops of each path. Moreover, SPDA transmits packets over the shortest path until it becomes invalid before it tries to utilize other alternative paths. In this paper we improve SPDA by adding the number of nodes each path passes through to the selection criteria. In the Improved SPDA (ISPDA), the available alternative paths have been utilized to transmit packets in parallel. We compare the SPDA and ISPDA regarding the throughput and delay. Results show the superiority of ISPDA over the original one.
文摘Mobile Ad-hoc Network (MANET) consists of mobile nodes that are connected via very dynamic multi-hop channels. Routing in MANET is a challenging task that has received great attention from researchers. In this paper we present Maximally Spatial Disjoint Multipath routing protocol (MSDM) which is a modification of AOMDV protocol. MSDM finds paths which are spatially separated and maximally disjointed. We think that sending various packets over spatially disjointed paths reduces the probability of collision occurrence and allows concurrent transmission over the set of different selected paths. Performance comparison of MSDM and AOMDV using GloMoSim simulator shows that MSDM is able to achieve a considerable improvement regarding some performance metrics such as delay, routing packets overhead, and network throughput.
文摘Content Based Image Retrieval (CBIR) is a technique in which images are indexed based on their visual contents and retrieving is only based upon these indexed images contents. Among the visual contents to describe the image details is shape. Shape of object, is considered as the most important distinguishable feature which living things can easily recognize, which is also a fact while this line is being written, and large efforts are currently underway in describing image contents by their shapes. Inspired by the core foundation of quantum mechanics, a new easy shape representation for content based image retrieval is proposed by borrowing the concept of quantum superposition into the basis of distance histogram. Results show better retrieval accuracy of the proposed method when compared with distance histogram.