Sensors, Vol. 19, Pages 4493: Spectrum-Efficient Resource Allocation in Multi-Radio Multi-Hop Cognitive Radio Networks
Sensors, Vol. 19, Pages 4493: Spectrum-Efficient Resource Allocation in Multi-Radio Multi-Hop Cognitive Radio Networks Sensors doi: 10.3390/s19204493 Authors: Bin Han Ying Luo Min Zeng Hong Jiang The multi-hop cognitive radio network (CRN) has attracted much attention in industry and academia because of its seamless wireless coverage by forming multi-hop links and high spectrum utilization of cognitive radio (CR) technology. Using multi-slot statistical spectrum status information (SSI), this work investigates the average spectrum efficiency (SE) of a multi-radio multi-hop (MRMH) CRN where each hop is permitted to use different spectra and long-distance hops can reuse the same idle primary user (PU) spectrum. Faced with the modeled SE problem, which is a complex non-convex fractional mixed integer nonlinear programming (MINLP) problem, the optimal spectrum and power allocation for multi-hop links in multi-slot and multi-channel scenarios can be obtained with the proposed successive multi-step convex approximation scheme (SMCA). As shown through computational complexity and simulation analysis, SMCA can obtain an approximate lower bound of the optimal solution for the modeled SE problem with a lower computational cost. Furthermore, some potential relationships between network performance and spectrum idle rate can be easily discussed with SMCA, which can provide some sensible deployment strategies for the MRMH CRN in future multi-slot scenarios.
Publication date: Available online 20 November 2019Source: Journal of Advanced ResearchAuthor(s): Sohail Mumtaz, Pradeep Bhartiya, Neha Kaushik, Manish Adhikari, Pradeep Lamichhane, Su-Jae Lee, Nagendra Kumar Kaushik, Eun Ha ChoiAbstractOver the past few decades, microwave (MW) radiation has been widely used, and its biological effects have been extensively investigated. However, the effect of MW radiation on human skin biology is not well understood. We study the effects of pulsed high-power microwaves (HPMs) on melanoma (G361 and SK-Mel-31) and normal human dermal fibroblast (NHDF) cells. A pulsed power generator (Chundo...
Passive measles immunity waned quickly, and most infants were no longer protected from measles by age 3 months, a study found; US experts say the age of vaccination should remain the same.Medscape Medical News
Suresh K. Mukherji
SURESH K. MUKHERJI, MD, MBA, FACR
NEUROIMAGING CLINICS OF NORTH AMERICA
Resting state functional connectivity (RSFC) has been widely studied in functional magnetic resonance imaging (fMRI) and is observed by a significant temporal correlation of spontaneous low-frequency signal fluctuations (SLFs) both within and across hemispheres during rest. Different hypotheses of RSFC include the biophysical origin hypothesis and cognitive origin hypothesis, which show that the role of SLFs and RSFC is still not completely understood. Furthermore, RSFC and age studies have shown an “age-related compensation” phenomenon. RSFC data analysis methods include time domain analysis, seed-based correl...
ConclusionLL/MLD4, MLA, MLD, the degree of luminal diameter stenosis, CCO, RI, and %APV derived from cCTA can support the detection of hemodynamically significant coronary stenosis as compared with iFR®, with LL/MLD4 showing the greatest discriminatory power.