Drone Detection and Defense Systems: Survey and a Software-Defined Radio-Based Solution.

With the decrease in the cost and size of drones in recent years, their number has also increased exponentially. As such, the concerns regarding security aspects that are raised by their presence are also becoming more serious. The necessity of designing and implementing systems that are able to detect and provide defense actions against such threats has become apparent.

Three-Event Energy Detection with Adaptive Threshold for Spectrum Sensing in Cognitive Radio Systems.

Implementation of dynamic spectrum access (DSA) in cognitive radio (CR) systems requires the unlicensed secondary users (SU) to implement spectrum sensing to monitor the activity of the licensed primary users (PU). Energy detection (ED) is one of the most widely used methods for spectrum sensing in CR systems, and in this paper we present a novel ED algorithm with an adaptive sensing threshold. The three-event ED (3EED) algorithm for spectrum sensing is considered for which an accurate approximation of the optimal decision threshold that minimizes the decision error probability (DEP) is found using Newton's method with forced convergence in one iteration.

Studies concerning the viability of the preserved kidney with perfusates other than plasma.

Based on previous data, this research deals with the study of cellular ultrastructure of renal tissue (cortical and medullary) in conditions of preservation through a continuous hypothermic pulsatile perfusion, using a solution that substitutes plasma as the perfusate. This experiment was done on isolated dog kidneys perfused with a specialized perfusion machine. The results clearly show that with this method of renal preservation, no major lesions or irreversible modifications of the nephrons occur within 12 hours, offering the organ posttransplanting compatibility.