Communication Systems
Mostrando 1-12 de 797 artigos, teses e dissertações.
-
1. Brazilian Psychiatric Association guidelines for the management of suicidal behavior. Part 3. Suicide prevention hotlines
Crisis hotlines are direct communication systems, usually telephone-based, set up to prevent suicide. However, few studies have evaluated their effectiveness. The present study aims to perform a systematic review, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework, of the effectiveness of interventions through dir
Brazilian Journal of Psychiatry. Publicado em: 2023
-
2. MGF Methods for Fixed and Gain Saturated Optically Preamplified FSO Links Impaired by Misalignments and Atmospheric Turbulence
Abstract The Gaussian approximation is commonly used to evaluate the performance of free space optical communication systems. However, other performance evaluation methods such as the saddle point approximation, Chernoff bound and the modified Chernoff bound have also been used. This paper investigates the performance of fixed and gain saturated optically pr
Journal of Microwaves, Optoelectronics and Electromagnetic Applications. Publicado em: 2022
-
3. Efficient Low-Complexity Optimized Channel Estimating Methods for OFDM-Based Low-Voltage Broadband Power Line Communication Systems
Abstract Broadband Power Line Communication (BB-PLC) technology enables data transmission for smart grid applications. Nevertheless, channel equalizers are required in the receiver to estimate and compensate for the nonlinear time-variant impulse response and noise interference effects introduced by the BB-PLC channel. In this paper, we append the Particle S
Journal of Microwaves, Optoelectronics and Electromagnetic Applications. Publicado em: 2022
-
4. A systematic review of observational, naturalistic, and neurophysiological outcome measures of nonpharmacological interventions for autism
Objective: Naturalistic and neurophysiological assessments are relevant as outcome measures in autism intervention trials because they provide, respectively, ecologically valid information about functioning and underlying neurocognitive mechanisms. We conducted a systematic review to highlight which specific neurophysiological techniques, experimental tasks,
Brazilian Journal of Psychiatry. Publicado em: 2022
-
5. Antecedent factors of violation of information security rules
Abstract Purpose This paper aims to investigate the influence of moral disengagement, perceived penalty, negative experiences and turnover intention on the intention to violate the established security rules. Design/methodology/approach The method used involves two stages of analysis, using techniques of structural equation modeling and artificial intellig
RAUSP Management Journal. Publicado em: 2022
-
6. Compact, Broadband, and Omnidirectional Antenna Array for Millimeter-Wave Communication Systems
Abstract In this paper, a millimeter-wave printed quadrupole antenna is proposed. It consists of two symmetric printed dipoles that make the quadrupole radiating power omnidirectionally. Such an arrangement eliminates the influence of the ground as reflector. Simulation results show that the quadrupole antenna exhibits a broad impedance bandwidth and an enha
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2021-06
-
7. Comparison Between Three- and Four-coil Wireless Power Transfer Systems with Resonant Coils
Abstract In this paper, it is demonstrated that the efficiency and ability to transfer power to the load in three-coil wireless power transfer (WPT) systems are always higher than in equivalent four-coil ones. On the other hand, it is shown that there are features attainable in four-coil WPT system that are not in three-coil ones. For instance, in a four-coi
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2021-03
-
8. Should ethanol be considered a treatment for COVID-19?
Abstract This paper describes the analysis of the effects of a frequency selective surface (FSS) on the characteristics of a microstrip line fed antenna with a bow-tie slot in the ground plane for operation in the frequency range 1 to 10 GHz. The use of the FSS is proposed to miniaturize the antenna structure and increase the number of resonance frequencies
Rev. Assoc. Med. Bras.. Publicado em: 2020-09
-
9. Effects of an FSS Reflector on a Microstrip Line Fed Bow-Tie Slot Antenna
Abstract This paper describes the analysis of the effects of a frequency selective surface (FSS) on the characteristics of a microstrip line fed antenna with a bow-tie slot in the ground plane for operation in the frequency range 1 to 10 GHz. The use of the FSS is proposed to miniaturize the antenna structure and increase the number of resonance frequencies
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2020-09
-
10. Was „eine Mädchen”, „eins Mädchen” und „Ø Mädchen” gemein haben: Zur Relevanz sprachtypologischer Korrelationen beim Transfer in die L2 Deutsch aus typologisch unterschiedlichen Sprachen
Abstract Whether for exchanging interpersonal needs -such as thoughts- or for business purposes -as in the case of the Lingua franca- in its specific form language has always been presumed to be the human species’ means for communication. With the concurrent rise in demand for multilingualism in the 20th century, studies examining language acquisition have
Pandaemonium ger.. Publicado em: 2020-04
-
11. QoS and QoE Aware Routing Protocol for Flying Ad-Hoc Surveillance Networks Using Fuzzy Inference Systems
Abstract The Flying Ad-hoc Network (FANET) networks have often operated in regions that are difficult to reach and have no fixed infrastructure. The use of devices such as Unmanned Aerial Vehicles (UAV) enable aerial networks to be created that are extremely fast, although there are no specific routing protocols for this type of network that can make communi
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2020-03
-
12. Mutual Coupling Reduction in Phased Array Antennas Applying High-Impedance Surface at X Band
Abstract This paper presents a microstrip phased array using High Impedance Surface - Electromagnetic Bandgap (HIS-EBG) in order to minimize the effects of mutual coupling among the antenna elements. Each element of the array is fed by a coaxial cable allowing the beam steering by controlling the signal of the input port of each element. This phased array op
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2020-03