Opportunistic usage selection of a licensed channel by a secondary user (SU) and its contention for data transmission is a challenging problem in coexisting cognitive radio network (CCRN). This is caused by the presence of many SUs from different CRNs in a shared environment, and the problem is further intensified when the user applications, with heterogeneous quality-of-service (QoS) requireme...

The FPGA overlay architectures have been mainly proposed to improve design productivity, circuit portability and system debugging. In this paper, we address the use of overlay architectures for building fault tolerant SRAM-based FPGA systems and discuss the main features and design challenges of a reliability-aware overlay architecture. Keywords— FPGAs; Overlay architectures; Reliability; Fault...

In peer-to-peer (P2P) overlay networks, the mechanism of a peer randomly joining and leaving a network, causes a topology mismatch between the overlay and the underlying physical topology. This causes a large volume of redundant traffic in the underlying physical network as well as an extra delay in message delivery in the overlay network. Topology mismatch occurs because overlay networks are n...

In research of overlay networks, simulator takes a very important role. However, popular simulators, such as ns and PlanetLab can’t meet the scale and performance requirement of overlay research. Although it is necessary for overlay researchers to observe activities of million nodes, current simulators can not give such simulation result. To improve the overlay network research efficiency, we d...

Distributed systems desire to construct a random overlay graph for robustness, efficient information dissemination and load balancing. A random walk-based overlay construction is a promising alternative to generate an ideal random scale free overlay in distributed systems. However, a simple random walk-based overlay construction can be affected by node churn. Especially, the number of edges inc...

Peer-to-peer networks can be divided into structured and unstructured based on their overlay topologies. In reality, unstructured p2p networks with superpeers have proved their capacities to support millions of users simultaneously. However, applications deployed on this kind of overlay networks, such as file-sharing, require flooding or gossip-based message routing, which puts more overhead on...

Electrical energy is indispensable for the economic growth and well-being of humanity. However, there a growing concern with conventional method generating electricity which by burning coal other fossil fuels. In coming decades, world will experience transition to cleaner energy, away from use One clean renewable energies that getting more popular advancing in technology wind energy. Wind requi...

Northern areas of Pakistan have blessed with extremely beautiful natural landscapes, waterfalls, glaciated mountains, biodiversity rich valleys and forests and have extraordinary potential for ecotourism. Study is designed to propose potential sites for ecotourism in Kohistan, which is a least developed but biodiversity rich area of Pakistan.  Poor planning and mismanagement of tourism practice...

Groundwater, being a vital resource, needs to be developed with proper understanding about its occurrence in time and space. Unscientific sand mining is a dominant environmental issue in this humid tropical river basin namely Bharathapuzha river basin geographically on central part of Kerala state, southwest part of India. The sandy layers along the river course declines its water holding capac...