10 research outputs found
Low Energy Consumption for Cooperative and Non-cooperative Cognitive Radio
Recently the subject of energy-efficient is very important in cognitive radio (CR), especially during spectrum sensing, since the large energy consumption (EC) cost, produces a restriction in their implementation especially in devices with limited power, i.e battery. In these design, energy detector consumes a significant part of energy during spectrum sensing to detect the activity of the primary user (PU). In this paper, we investigated a method for improving EC in two scenarios: non-cooperative and cooperative. The idea behind the improvement is based on sensing the spectrum with low-density samples. The optimization concept for reducing EC through controlling the number of frequency samples to be sensed is illustrated as well as the probability of detection in both scenarios. To evaluate the proposed method a comparison is made between the proposed method and censoring method. The performance of energy detection system is evaluated in AWGN and Rayleigh fading channels. The simulation results show that in non-cooperative scenario at Eb/No equal 10 dB, and for sensing ratio equal 50%, EC decreases by 50% and 46% with sma loss in of detection probability of 5% in AWGN channel and 12% in Rayleigh channel. In cooperative scenario, the results show that as the number of cognitive users (CU) increased the average EC per user decreased with an improvement in probability of detection. In case of sensing ratio 50%, the EC is decreased by 43.6% as compared with censoring method
Slepton Flavor Nonuniversality, the Muon EDM and its Proposed sensitive Search at Brookhaven
We analyze the electric dipole moment of the electron (), of the neutron
() and of the muon () using the cancellation mechanism in the
presence of nonuniversalities of the soft breaking parameters. It is shown that
the nonuniversalities in the slepton sector produce a strong violation of the
scaling relation in the cancellation region. An
analysis of and under the constraints of the current
experimental limits on and and under the constraints of the recent
Brookhaven result on shows that in the non-scaling region
can be as large as ()ecm and thus within reach of the
recently proposed Brookhaven experiment for a sensitive search for at
the level of ecm.Comment: 24 pages, Latex, including 5 figures with additional reference
Tailoring optical transmittance of polyvinyl alcohol by FeCl3-doping for photovoltaic application
A comprehensive review of barriers to a functional Zakat system in Nigeria: what needs to be done?
Purpose: Muslims in Nigeria, like in many Muslim-majority countries, are striving to have a functional Zakat system in search of solutions to the perennial problem of poverty and its damning consequences. Nevertheless, there are still unsettled concerns arising from the current and widespread implementation of dissimilar (diverse) approaches to the Zakat system in various parts of the country. The purpose of this paper is to review comprehensively what are the hindrances of a vibrant Zakat system and how far the identified impediments may affect the system in the Nigerian context.Design/methodology/approach:The methodology adopted is the review of extant relevant literature in the field of scholarly publications.Findings: The findings of this study revealed that the fragmented implementation of the Zakat system within the context of the Nigerian democratic system of government lead to the weak governance with respect to law, administration and management; lack of a generally accepted fatwa from the Muslims scholars (Ulamas); absence of Zakat accounting standard; and low compliance behavior are the major barriers that require the attention of government and other stakeholders such as the traditional leaders, the accounting regulatory bodies, the Ulamas, as well as the economic and accounting researchers.Practical implications: It was recommended that the stakeholders should make concerted efforts toward ensuring success of the Zakat system for attaining salvation in the hereafter and for social security, as well as economic prosperity.
Originality/value: The paper is the first paper that comprehensively reviews previous literature in the Zakat environment on factors that become barriers to implement a comprehensive Zakat system in Nigeria
Assessment of noise reduction in ultrasound images of common carotid and brachial arteries
The present study assessed the use of filters for noise reduction in ultrasound images of the common carotid artery (CCA) and brachial artery using intima-media thickness, which is a safe and non-invasive technique for determining subclinical atherosclerosis and cardiovascular risk. A new combined speckle reducing anisotropic diffusion (SRAD) filter for noise reduction is then proposed. Ultrasonic examination of both arteries was performed on 30 men (aged 40 ± 5 years). The programme was designed using MATLAB software to extract consecutive images in bit map format from the audio video interleaves. An additional programme was designed in MATLAB to apply the region of interest (ROI) to the thickness of the intima-media of the posterior walls of the arteries. Block-matching techniques were used to estimate arterial motion from ultrasound images of the B-mode CCA and brachial artery. Different noise reduction filters and Canny edge detection were carried out separately in the ROI. The programme measured mean square error (MSE) and peak signal-to-noise ratio (PSNR). The results demonstrated that the new combined SRAD filter with Canny edge detection identified the lowest value for MSE and the highest value for PSNR in 90 consecutive frames (~3 cardiac cycles). The results indicate that MSE and PSNR were better detected by the proposed combined SRAD filter with Canny edge detection than did several commonly used filters with Canny detection for speckle suppression and preservation detail in carotid and brachial arteries ultrasound images. © The Institution of Engineering and Technology