Real-time structural health monitoring requires dynamic sensing of distributed strain and temperature. Brillouin Optical Time Domain Analysis (BOTDA) and Rayleigh Coherent Optical Time Domain Reflectometry (COTDR) are promising candidates to achieve dynamic sensing. A noise model with specific parametric simulation of independent laser and detector noise sources has been developed. Although ens...

Cognitive radio (CR) technology has been suggested for effective use of spectral resources. Spectrum sensing is one of the main operations of CR users to identify the vacant frequency bands. Cooperative spectrum sensing (CSS) is used to increase the performance of CR networks by providing spatial diversity. The accuracy of spectrum sensing is the most important challenge in the CSS process sinc...

Nowadays, the number of smartphone users is growing rapidly. Recent smartphones equipped with several sensors are convenient tools for collecting information in participatory sensing environment. However, contributing sensing data require time and monetary cost which hinder may people from participation. To realize active and efficient sensing activities, incentive mechanism is indispensable. T...

The motivation behind cognitive radio networks (CRNs) was to increase the utilization of the underutilized wireless spectrum bands. An important factor to achieving this goal is fast sensing, because if the cognitive radio (CR) node has one transceiver for sensing and transmission, then the longer the sensing time, the less the transmission time left and the lower the wireless spectrum band uti...

In this paper, we investigate the energy efficiency and throughput optimization problem of cognitive relay networks. We propose to design sensing time and signal to noise ratio (SNR) to maximize the energy efficiency and throughput, since analytical and empirical studies have shown that sensing time and SNR are key factors for energy efficiency and throughput. We design a method that simultaneo...

Multiple secondary users can cooperate to increase the reliability of spectrum sensing in cognitive radio networks. However, the total transmission power grows approximately linearly with the number of cooperative secondary users. This paper proposes a new approach to optimize the trade-off between sensing reliability and power efficiency in cooperative cognitive radio networks over fading chan...

the purpose of this study was to determine the plant density of sugar beet fields in qazvin region using satellite images and remote sensing techniques. the plant density can be used to estimate the pre-harvest sugar beet yield and as a result the proper management of agricultural and industrial processes involved in sugar production. satellite data can be used to remove the cost and time of co...

Article history: Available online 2 October 2013