Search results for "TELECOMMUNICATION"

On a Planar Dynamical System Arising in the Network Control Theory

2016

We study the structure of attractors in the two-dimensional dynamical system that appears in the network control theory. We provide description of the attracting set and follow changes this set suffers under the changes of positive parameters µ and Θ.

Discovering Differential Equations from Earth Observation Data

2020

Modeling and understanding the Earth system is a constant and challenging scientific endeavour. When a clear mechanistic model is unavailable, complex or uncertain, learning from data can be an alternative. While machine learning has provided excellent methods for detection and retrieval, understanding the governing equations of the system from observational data seems an elusive problem. In this paper we introduce sparse regression to uncover a set of governing equations in the form of a system of ordinary differential equations (ODEs). The presented method is used to explicitly describe variable relations by identifying the most expressive and simplest ODEs explaining data to model releva…

Generalized Thru-Reflect-Line Calibration Technique for the Measurement of Multimodal Radiating Waveguides

2017

The objective of this letter is to extend the use of the generalized thru-reflect-line measurement technique to the case of a radiating multimodal rectangular waveguide aperture. Although this radiating aperture has been carefully studied from a theoretical point of view, the relevant experimental characterization has been limited to the case where the feeding waveguide is monomodal. In addition to theory, we also present experimental results that agree quite well with full-wave simulations, thereby fully validating the measurement technique.

Large area conductive nanoaperture arrays with strong optical resonances and spectrally flat terahertz transmission

2017

Using simple and inexpensive nanosphere lithography, we produce large, centimeter-squared sized thin golden films patterned with a hexagonal array of nanoapertures with controllable dimensions on the order of 100–300 nm, spaced by a 350–375 nm pitch distance. The optical transmission spectra of our samples are dominated by the resonant plasmonic features in the spectral range 500–700 nm, caused by the nanostructure in the film. At the same time, the transmission at terahertz (THz) radiation is as high as ∼10% and is spectrally flat. Our measurements are in agreement with finite difference time domain simulations. Such thin metal hole array films allow for very efficient injection of optical…

Activation of α1A-adrenoceptors desensitizes the rat aorta response to phenylephrine through a neuronal NOS pathway, a mechanism lost with ageing

2017

Background and purpose A NO-mediated desensitization of vasoconstrictor responses evoked by stimulation of α1 -adrenoceptors has been reported in different vessels. We investigated the involvement of each α1 -adrenoceptor subtype and constitutive NOS isoforms and the influence of ageing and hypertension on this process. Experimental approach Wistar and spontaneously hypertensive rats (SHR), 16, 32, 52 and 72 weeks-old, were used to evaluate the desensitization process. Expression of α1 -adrenoceptor subtypes, endothelial NOS (eNOS) and neuronal NOS (nNOS) were determined in rat aorta and left ventricle (LV). Expression levels were also evaluated in LV of a group of heart failure patients wi…

Reply to: “Performance status in patients with HCC: New kid on the block”

2017

“New Kids on the Block” — The Game Changers. The Role of Immune Check Point Blockade in Personalised Treatment of Prostate, Urinary Bladder and Kidne…

2021

Abstract Early detection and diagnosis of cancer followed by a personalised approach to treatment is a key and can save lives. It has been an important issue in both the medical and social fields. The search for instruments and/or diagnostics tools able to detect cancers at an early stage has led to consideration of the usage of various approaches, such as exhaled air, biomarkers in blood, urine testing as well as imaging techniques. This actual time and everything that is happening around us could be characterised as a strange and very unpredictable time. This comparison could be made not only due to the actual coronavirus situation, but also the same can be noticed in the personalised med…

Arm Hypervisor and Trustzone Alternatives

2020

Many scenarios such as DRM, payments, and homeland security require a trusted and verified trusted execution environment (TEE) on ARM. In most cases such TEE should be available in source code mode. The vendor cannot conduct code review and ensure that the operating system is trustworthy unless source code is available. Android and other rich execution environments (REEs) support various TEE implementations. Each TEE implementation has its own unique way of deploying trusted applications and features. Most TEEs in ARM can be started at TrustZone™ or Hyp (Hypervisor) mode. Choosing a proper TEE operating system can be a problem for trusted application developers and hardware vendors. This ar…

Drone arc routing problems

2018

[EN] In this article, we present some drone arc routing problems (Drone ARPs) and study their relation with well-known postman ARPs. Applications for Drone ARPs include traffic monitoring by flying over roadways, infrastructure inspection such as by flying along power transmission lines, pipelines or fences, and surveillance along linear features such as coastlines or territorial borders. Unlike the postmen in traditional ARPs, drones can travel directly between any two points in the plane without following the edges of the network. As a consequence, a drone route may service only part of an edge, with multiple routes being used to cover the entire edge. Thus the Drone ARPs are continuous o…

Methodology and trends for an intelligent transport system in developing countries

2018

Abstract Increasingly, the technologies that are used in telecommunications contribute to improve intelligent transport systems. These technologies are systems that offer several concepts like vehicular ad hoc networks, which allow reduction of traffic accidents, traffic congestion and consequently increase road safety and the comfort of road users. Developing countries in general and those of sub-Sahara in particular do not have telecommunication infrastructures, even road infrastructures for the implementation of an intelligent transport system. Moreover, with the serious increase in vehicles in these countries, the problem of traffic regulation arise especially in the inter-urban context…