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The proliferation of low-cost, small radar cross-section UAVs (unmanned aerial vehicles) necessitates innovative solutions for countering them. Since these UAVs typically operate with a radio control link, a promising defense technique involves passive scanning of the radio frequency (RF) spectrum to detect UAV control signals. This approach is enhanced when integrated with machine-learning (ML) and deep-learning (DL) methods. Currently, this field is actively researched, with various studies proposing different ML/DL architectures competing for optimal accuracy. However, there is a notable gap regarding robustness, which refers to a UAV detector's ability to maintain high accuracy across diverse scenarios, rather than excelling in just one specific test scenario and failing in others. This aspect is critical, as inaccuracies in UAV detection could lead to severe consequences. In this work, we introduce a new dataset specifically designed to test for robustness. Instead of the existing approach of extracting the test data from the same pool as the training data, we allowed for multiple categories of test data based on channel conditions. Utilizing existing UAV detectors, we found that although coefficient classifiers have outperformed CNNs in previous works, our findings indicate that image classifiers exhibit approximately 40% greater robustness than coefficient classifiers under low signal-to-noise ratio (SNR) conditions. Specifically, the CNN classifier demonstrated sustained accuracy in various RF channel conditions not included in the training set, whereas the coefficient classifier exhibited partial or complete failure depending on channel characteristics. [ABSTRACT FROM AUTHOR]

Researchers of 5G-sliced Wireless Networks are faced with the task of achieving, at the same time, (i) mandatory isolation among network slices and (ii) the effective utilization of resource at Fifth Generation Base Station (gNB). This article proposes the second version of the Preemption-based service Prioritization (PP2) scheme that merges the capabilities of the classical Resource Reservation (RR) and Service Prioritization (SP) schemes and realizes the coexistence of non-TCP streaming and TCP elastic traffic at gNB. Analytical methods are given for Dynamic Resource Sharing (DRS) and Dynamic Resource Reallocation (DRR) with data rate reduction and service preemption. As main results, under some baseline scenario, the PP2 scheme, in comparison with RR, does increase the admission probability up to 99.999% at the system while ensuring 100% in system capacity utilization. [ABSTRACT FROM AUTHOR]

We explore the influence of radio-mode feedback on the properties of the cool circumgalactic medium (CGM). To this end, we assemble a statistical sample of approximately 30,000 radio galaxies with background quasars by combining optical spectroscopic measurements of luminous red galaxies and quasars from the year 1 data set of the Dark Energy Spectroscopic Instrument and radio sources from the LOw-Frequency ARray Two-metre Sky Survey (LoTSS) DR2 catalog and the Very Large Array Sky Survey (VLASS) quick-look catalog. Galaxies with similar optical properties but with no radio counterparts in LoTSS and VLASS are selected as the control group. We measure the cool CGM properties of radio galaxies and their control samples traced by Mg ii absorption lines, including covering fraction, rest equivalent width, and gas kinematics. Our results show no significant difference in the properties of gas around radio galaxies and their control sample, indicating that the operating radio-mode feedback of massive galaxies does not produce detectable effects on the properties of the cool CGM. Finally, we show that the CGM of radio galaxies contains a nonnegligible amount of cool gas with approximately 1010 M ⊙. This abundance can place a stringent constraint on the radio-mode feedback models. [ABSTRACT FROM AUTHOR]

As the number of subscribers for Long Term Evolution (LTE) technology and associated resources increase, it has become mandatory for the LTE mobile operators to evaluate how efficiently the existing LTE cell network will perform in real-time scenarios. Controlling the transmitting services in the LTE cell network is an important factor as it assists in increasing the entire network execution. The best way to attain this is to attain the integrity between the users or achieve the efficient values of spectral efficiency (SE) and energy efficiency (EE). Spectral efficiency and energy efficiency are important parameters for a cellular network to exhibit its network performance level. In this paper, the real-time information records of approximately 50000 BTS sites, which were comprised of Key Performance Indicators (KPIs) such as Radio Resource Control (RRC), E-UTRAN Radio Access Bearer (ERAB), Packet drop, etc. have been considered. From the data set, throughput has been predicted using the Random Forest Algorithm. Further Spectral and Energy efficiency has been predicted. Spectral efficiency (SE) helps in controlling the transmitting power of the cell network and Energy Efficiency helps in enhancing the network quality of service (QoS). The maximum value of the spectral and energy efficiency at the uplink throughput and downlink throughput had been taken from the Nokia Drive Test sheet. If the predicted values lie beyond the limits of the network, it will indicate that the network performance has deteriorated and has scope of improvement. The resulting variables were chosen on the basis of the real field assessment by the Nokia Network Pvt. Ltd in India. [ABSTRACT FROM AUTHOR]

Unlike in neighbouring countries, Spanish radio stations were subject to a severe censorship regime for most of the twentieth century. After the end of the civil war (1939), General Franco's regime issued regulations to control the press and radio. In the case of newspapers, the Press Act (1966) eased this surveillance, but such relief did not apply to radio broadcasting. However, in the second half of Franco's dictatorship, some local stations and, especially, a nation-wide radio station (Cadena SER) tried to bypass restrictions set by the authorities. This article covers different initiatives, paying special attention to those developed by Cadena SER, which played a decisive role in liberalising information. To this end, journalists who played a key role in this transition were interviewed. As a result of this research, it has been observed that, despite the threats, disobedience was a constant from the 1960s onwards. Such disobedience was not always aimed at fighting the regime during this time of social change, but also responded to the broadcasters' commercial strategies. It has also been found that certain authorities facilitated these activities through their personal influence. [ABSTRACT FROM AUTHOR]

Deploying Cellular Internet of Things (CIoT) devices in urban and remote areas faces significant energy efficiency challenges. This is especially true for Narrowband IoT (NB-IoT) devices, which are expected to function on a single charge for up to 10 years while transmitting small amounts of data daily. The 3rd Generation Partnership Project (3GPP) has introduced energy-saving mechanisms in Releases 13 to 16, including Early Data Transmission (EDT) and Preconfigured Uplink Resources (PURs). These mechanisms extend battery life and reduce latency by enabling data transmission without an active Radio Resource Control (RRC) connection or Random Access Procedure (RAP). This paper examines these mechanisms using the LENA-NB simulator in the ns-3 environment, which is a comprehensive framework for studying various aspects of NB-IoT. The LENA-NB has been extended with PURs, and our analysis shows that PURs significantly enhance battery life and latency efficiency, particularly in high-density environments. Compared to the default RAP method, PURs reduce energy consumption by more than 2.5 times and increases battery life by 1.6 times. Additionally, PURs achieve latency reductions of 2.5–3.5 times. The improvements with PURs are most notable for packets up to 125 bytes. Our findings highlight PURs' potential to enable more efficient and effective CIoT deployments across various scenarios. This study represents a detailed analysis of latency and energy consumption in a simulated environment, advancing the understanding of PURs' benefits. [ABSTRACT FROM AUTHOR]

Current cutting-edge solutions to the spectrum shortage problem are unable to meet the growing demand for a limited spectrum. A key dimension beyond state-of-the-art solutions is to exploit the free spectrum more effectively. Although various schemes have been proposed for trading spectrum, few studies have focused on optimal admission of spectrum requests for maximizing service providers' (SP's) profit. Thus, this timely study presents a novel intelligent admission scheme for spectrum requests from the perspective of a non-cooperative game, in which the information of all participants (customers and providers) is incomplete to others, and each player wishes to maximize its benefit. The proposed control admission policy may evict clients in-service to release spectrum for serving certain, e.g., wealthy clients. Evicted clients are compensated using a dynamic strategy that adopts greedy game theory to capture the conflict of interest between SP and evicted users. Simulation experiment results validate and demonstrate the feasibility and efficiency of the proposed scheme, compared to a benchmark reinforcement learning approach and another widely used scheme for admission and eviction control of cognitive radio users. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The laser system is the most complex component of a light-pulse atom interferometer (LPAI), controlling frequencies and intensities of multiple laser beams to configure quantum gravity and inertial sensors. Its main functions include cold-atom generation, state preparation, state-selective detection, and generating a coherent two-photon process for the light-pulse sequence. To achieve substantial miniaturization and ruggedization, we integrate key laser system functions onto a photonic integrated circuit. Our study focuses on a high-performance silicon photonic suppressed-carrier single-sideband (SC-SSB) modulator at 1560 nanometers, capable of dynamic frequency shifting within the LPAI. By independently controlling radio frequency (RF) channels, we achieve 30-decibel carrier suppression and unprecedented 47.8-decibel sideband suppression at peak conversion efficiency of -6.846 decibels (20.7%). We investigate imbalances in both amplitudes and phases between the RF signals. Using this modulator, we demonstrate cold-atom generation, state-selective detection, and atom interferometer fringes to estimate gravitational acceleration, g ≈ 9.77 ± 0.01 meters per second squared, in a rubidium (87Rb) atom system. [ABSTRACT FROM AUTHOR]

This letter presents a method for accurately calculating radio frequency (RF) power in a standing wave transmission line system. The proposed approach utilizes two directional couplers in conjunction with a low‐level radio frequency control system. RF power is determined through the application of proposed equations derived from amplitude and phase measurements of coupling signals obtained from the two directional couplers. Experimental validation of the method is conducted using two directional couplers with directivities of 26 and 28 dB, respectively, operating at 162.5 MHz across the entire wavelength. Results indicate that employing a single directional coupler yields average power errors of approximately 6.6% and 5.8%, respectively. However, by implementing the proposed method, the measurement error can be reduced to approximately 1.0%. [ABSTRACT FROM AUTHOR]

This paper presents a composite control algorithm for the radio telescope servo control system to address the target tracking and matched/mismatched disturbance suppression problems. The algorithm consists of the equivalent-input-disturbance (EID) approach and the optimal control method. An EID estimator is developed using the difference between the estimated output of the state observer and the measurement output and then the estimate of the EID is fed forward into the control input to reject the disturbance. A cost function with clear physical meaning is selected and the weighting parameters are adjusted for the optimal controller to improve tracking performance. Considering the nonminimum phase characteristics of the radio telescope system, the state observer gain is computed using the linear matrix inequality (LMI) method. The system stability is analyzed using the small gain theorem, and the linear quadratic regulator (LQR) control method is utilized to determine the state feedback gain. Finally, the composite controller is designed for an identified telescope model. Simulation results show that for the tracking performance, the settling time of proposed method is 1.13 s and reduces by about 0.32 s and 0.87 s than that of the ADRC controller and PI controller, respectively. For the antidisturbance performance, the RMS value and the maximum error of the proposed method are 0.0039 and 0.0128, which are 42.86% and 40.38% of the ADRC controller and 30.71% and 27.77% of the PI controller, respectively, which indicates that the proposed method has better control performance. In addition, the proposed controller has certain robustness to systematic parameter perturbations. [ABSTRACT FROM AUTHOR]

Radio log book records are one of the significant deficiencies items in port state controls. This study attempts to reveal the legislative gaps in radio log book inspections and to prevent deficiencies related to radio log book records. To address this issue, the annual reports from 2015 to 2020 of nine MoUs are analysed, and the deficiencies of the radio log book records from 2016 to 2020 in the USCG inspections are determined. In order to identify the radio log book records correctly, international regulations are widely scrutinised. In addition to all of these investigations, experts' assessments are also consulted. Based on the investigation results, we derive three conclusions. First, according to Paris MoU data, 32.9% to 39.4% of the deficiencies in radio communication arise from radio log book records. Second, there are inadequate regulations on how to keep compulsory radio log book records. Third, some contradictions and uncertainties regarding the compulsory records are determined. [ABSTRACT FROM AUTHOR]

Troops in the context of reconnaissance or search tasks to find out the enemy in difficult, protected and disguised terrain is an element of vulnerability that needs to be taken into account. If you insist on finding out the enemy's condition, there is a possibility that contact will occur early and cause casualties which could thwart the main task. Therefore, a tool or robot is needed to help obtain data about protected enemies by diverting the enemy's attention and providing resistance. The aim of this research is to create a prototype chainwheeled combat robot platform system that is capable of maneuvering, firing SS2 and rockets, detecting mine-prone areas, and detecting body thermals. The robot control system consists of a mobile controller and a base station. The mobile controller functions to control robot movements such as forward, backward, right turn, left turn, weapon azimuth movement, weapon elevation movement and shooting using 2.4 GHz radio control and target monitoring using FPV ((First person view) directly in the field on a frequency of 5.6 GHz, base station functions to control the robot's movement and monitor targets using a laptop via the internet. The robot system is equipped with GPS and a metal detector, so that the robot's position can be monitored and report the presence of mines to the base station. Thus, the robot created is expected to be able to help to combat duty in the context of war military operations [ABSTRACT FROM AUTHOR]

Color-center defects in silicon carbide promise opto-electronic quantum applications in several fields, such as computing, sensing, and communication. In order to scale down and combine these functionalities with the existing silicon device platforms, it is crucial to consider SiC integrated optics. In recent years, many examples of SiC photonic platforms have been shown, like photonic crystal cavities, film-on-insulator waveguides, and micro-ring resonators. However, all these examples rely on separating thin films of SiC from substrate wafers. This introduces significant surface roughness, strain, and defects in the material, which greatly affects the homogeneity of the optical properties of color centers. Here, we present and test a method for fabricating monolithic single-crystal integrated-photonic devices in SiC: tuning optical properties via charge carrier concentration. We fabricated monolithic SiC n-i-n and p-i-n junctions where the intrinsic layer acts as waveguide core, and demonstrate the waveguide functionality for these samples. The propagation losses are below 14 dB/cm. These waveguide types allow for addressing color centers over a broad wavelength range with low strain-induced inhomogeneity of the optical-transition frequencies. Furthermore, we expect that our findings open the road to fabricating waveguides and devices based on p-i-n junctions, which will allow for integrated electrostatic and radio frequency control together with high-intensity optical control of defects in silicon carbide. [ABSTRACT FROM AUTHOR]

For several decades, Brazil's Grupo Globo, which controls radio, TV, and newspaper, served as the hegemonic voice controlling the audio, visual, and narrative dimensions of social phenomena that formed and informed social, political, and cultural attitudes among Brazilians. Of all their divisions, none has been more influential than the TV Globo network. Lately, with the popularization of free access to digital media, such as those offered by YouTube, TV Globo's viewership has substantially declined. This paper discusses the concept of controlling images to analyze examples of TV Globo's constructed visual image of the hypersexualized Afro-Brazilian female body in the network's soap operas. It also analyzes cases of TV Globo's constructed narrative over another subaltern Brazilian group: the LGBTQIA+ community. Recently, Afro-Brazilian and Queer-centric YouTube channels have attracted subscribers by emphasizing content centered on negritude, gender politics, and place of speech while deconstructing and de-normalizing Eurocentric and patriarchal controlling images. Against examples of TV Globo's normative discourse of the past decades, the YouTube channels discussed in this paper represent alternative mediums for agency, visibility, and unbiased representations of gender and racial identities in Brazil. [ABSTRACT FROM AUTHOR]

5G mobile networks provide two main uses: enhanced mobile broadband (eMBB) and ultra-reliable lowlatency communications (uRLLC) are two critical services. While eMBB focuses on maximum data rate, uRLLC prioritizes latency and reliability. However, sharing radio resources between these two use cases creates a complex planning problem due to the trade-off between these different factors. Our proposal introduces an efficient control strategy that optimizes the use of licensed and unlicensed radio resources across various services i.e., eMBB with guaranteed bit rate (eMBB-GBR) and uRLLC ensuring that the traffic requirements of each service are met. The main objective of the proposed control strategy is to maximize the utilization of resources by ensuring the availability of resources, reducing delays, and achieving high throughput. The simulation results clearly show the superiority of the proposed algorithm compared to the reference scheme. This significantly improves the performance of the network by improving the utilization of resources, reducing latency service, increasing the rate of successful packets, and reducing the probability of blocking. The algorithm shows significant improvements, particularly with an 8%, 22%, and 28 % increase in effective capacity for the eMBB-GBR service compared to the reference approaches when the session arrival rate is 1.2. In addition, it significantly reduces the probability of session drops for eMBB-GBR service by about 0.05, 0.12, and 0.17 compared to the reference approaches. Moreover, the proposed control strategy has a significant relative latency for uRLLC service of 13%, 21 %, and 26% compared to reference approaches when URLLC density is around 1000 UEs. [ABSTRACT FROM AUTHOR]

Anisotropic plasma-enhanced atomic layer etching (ALE) requires directional ions with a well-defined ion energy to remove materials in a highly selective and self-limiting fashion. In many plasma etching systems, the ion energy is controlled using radio-frequency (13.56 MHz) sinusoidal waveform biasing. However, this yields ions with a broad energy distribution, while also inducing electron heating mechanisms that can affect the ion flux. In this work, we report on precise ion energy control—independent of the ion flux—using low-frequency (LF: 100 kHz) tailored bias voltage waveforms in a commercial remote plasma reactor. A prototype LF bias generator has been used to apply tailored waveforms consisting of a positive voltage pulse and a negative linear voltage ramp. These waveforms yielded ions having narrow energy distributions (7 ± 1 eV full-width-at-half-maximum) measured on dielectric SiO2 substrates for ion energies up to 200 eV in collisionless Ar plasmas. The mono-energetic ions were used to etch SiO2 thin films by physical sputtering. In these sputter etch experiments, the ability to accurately control the ion energy in the <100 eV range is demonstrated to allow for a more precise determination of sputter thresholds, which serve as valuable input for the design of novel ALE chemistries. The feasibility of performing anisotropic plasma etching using LF tailored waveform biasing was established by etching a SiO2 layer on a 3D trench nanostructure. The potential merits of this technique for the field of atomic scale processing are discussed. [ABSTRACT FROM AUTHOR]

In recent years, the development of intelligent reflecting surface (IRS) in wireless communications has enabled control of radio waves to reduce the detrimental impacts of natural wireless propagation. These can achieve significant spectrum and energy efficiency in wireless networks. Non-orthogonal multiple access (NOMA) technology, on the other hand, is predicted to improve the spectrum efficiency of fifth-generation and later wireless networks. Motivated by this reality, we consider the IRS-based NOMA network in the downlink and uplink scenario with a pernicious eavesdropper. Moreover, we investigated the physical layer security (PLS) of the proposed system by invoking the connection outage probability (COP), secrecy outage probability (SOP), and average secrecy rate (ASR) with analytical derivations. The simulation results reveal that (i) it is carried out to validate the analytical formulas, (ii) the number of meta-surfaces in IRS, transmit power at the base station, and power allocation parameters all play an essential role in improving the system performance, and (iii) it demonstrates the superiority of NOMA to the traditional orthogonal multiple access (OMA). [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicle is an unmanned aircraft operated by radio remote control equipment and self-provided program control device. The flight control system is the core of the entire flight process of unmanned aerial vehicle to complete take-off, mission execution and recovery. The classical proportion integral differential controller is widely used in the modern control field because of its simple principle and flexible implementation. However, tuning proportion integral differential parameters depends on lots of experience. In this paper, a three-layer feedforward neural network is proposed and used to stabilize the unmanned aerial vehicle edge control system. A novel weight and structure determination method that incorporates bionic beetle swarm optimization algorithm, called beetle swarm optimization weight and structure determination algorithm, is proposed to train the three-layer neural network. Furthermore, the sigmoid activation functions are utilized in the beetle swarm optimization weight and structure determination algorithm to identify the ideal weight and structure of the neural network when dealing with fitting and validation. Then, other five algorithms are added for the comparative analysis, namely particle swarm optimization algorithm, genetic algorithm, bat algorithm, firefly algorithm and artificial bee colony algorithm. In this way, the performance improvement of the beetle swarm optimization algorithm can be highlighted. Finally, the application of unmanned aerial vehicle edge control is given by using two different control methods respectively, i.e., the proportion integral differential controller and the beetle swarm optimization weight and structure determination neural network. It can be seen from the results that the beetle swarm optimization weight and structure determination neural network can enable the unmanned aerial vehicle to better achieve trajectory tracking by showing a better performance on edge control. [ABSTRACT FROM AUTHOR]

Currently, it is more efficient to use LEO small spacecraft as radio control points to determine the compliance of the radiation parameters of electronic means with the relevant norms and conditions of permits for the use of the radio frequency spectrum. Such satellite radio monitoring systems make it possible to determine the parameters of signals and the location of radio-electronic means over a large area with a diverse terrain, which will increase the efficiency of radio monitoring systems. When performing such tasks, one of the most important parameters is the detection and isolation of a useful signal against the background of noise and interference. For such purposes, it is effective to use Kalman filters. It was found that the Kalman filter can detect and isolate useful signals against the background of noise and interference with very high accuracy. However, when solving such problems, problems arise related to the stability of the method to the choice of the initial state of the filter and the inevitable distortion of the frequency of the desired signal due to the presence of the Doppler effect. In the course of this study, it was found that the similarity coefficient depends on the noise level, but it does not actually depend on frequency distortion. It was also found that when the SNR ratio is greater than 0 dB, the radio signal at the input of the on-board measuring receiver will be received with a reliability of more than 90 %. Therefore, it can be concluded that the signal detection method for satellite radio monitoring based on the use of the Kalman filter is resistant to possible frequency distortions of the desired signal due to the Doppler effect and does not affect the correctness and speed of decisions made [ABSTRACT FROM AUTHOR]

With developments in OpenRAN and software-defined radio (SDR), the mobile networking implementations for radio and security control are becoming increasingly software-based. We design and build a lightweight and distributed software assurance scheme, which ensures that a wireless user holds the correct software (version/code) for their wireless networking implementations. Our scheme is distributed (to support the distributed and ad hoc networking that does not utilize the networking-backend infrastructure), lightweight (to support the resource-constrained device operations), modular (to support compatibility with the existing mobile networking protocols), and supports broadcasting (as mobile and wireless networking has broadcasting applications). Our scheme is distinct from the remote code attestation in trusted computing, which requires hardwarebased security and real-time challenge-and-response communications with a centralized trusted server, thus making its deployment prohibitive in the distributed and broadcasting-based mobile networking environments. We design our scheme to be prover-specific and incorporate the Merkle tree for the verification efficiency to make it appropriate for a wireless-broadcasting medium with multiple receivers. In addition to the theoretical design and analysis, we implement our scheme to assure srsRAN (a popular open-source software for cellular technology, including 4G and 5G) and provide a concrete implementation and application instance to highlight our scheme's modularity, backward compatibility to the existing 4G/5G standardized protocol, and broadcasting support. Our scheme implementation incorporates delivering the proof in the srsRAN-implemented 4G/5G cellular handshake and connection establishment in radio resource control (RRC). We conduct experiments using SDR and various processors to demonstrate the lightweight design and its appropriateness for wireless networking applications. Our results show that the number of hash computations for the proof verification grows logarithmically with the number of software code files being assured and that the verification takes three orders of magnitude less time than the proof generation, while the proof generation overhead itself is negligible compared to the software update period. [ABSTRACT FROM AUTHOR]

• 15 in-vehicle distractions were studied to compare their visual distraction effects. • Some tasks diverted the drivers' visual attention for over 40 % of the task time. • All tasks caused a reduction in the variability of gaze direction onto the windshield. • Controlling and managing in-vehicle systems is a major source of visual distraction. Distractions to the driving process, whether inside or outside of the vehicle, are becoming an increasing problem, especially distractions that are voluntary in nature which are avoidable but seem to be prevalent on our streets. A research gap was identified in the lack of comparability of in-vehicle distraction influences on drivers' visual attention. The paper presents research on the effects of in-vehicle distractions on drivers' visual attention, which was performed with 23 participants in a real environment (test track) during normal traffic conditions. The drivers were subjected to 15 in-vehicle distractions, including mobile phone use (handheld and hands-free), finding items inside the vehicle, and controlling and managing various in-vehicle systems. All distractions caused a significant reduction in visual attention to driving-related areas, including tasks such as setting the climate control or radio frequency, which are generally not perceived as disruptions. In fact, setting the climate control, navigational system, and radio frequency diverted visual attention for more than 40 % of the whole task duration. All tasks caused a reduction in the variability of gaze direction onto the windshield, indicating an occurrence of vision tunnelling, which was again very prominent even with tasks that are usually not perceived as very distracting, such as adjusting the side mirrors. The results, therefore, show that in-vehicle tasks that are voluntary in nature may significantly affect drivers' visual attention, and this is not limited to mobile phone and entertainment system use. [ABSTRACT FROM AUTHOR]

We present a framework for building ArtificialNeuralNetworks (ANNs) able to control a quadcopter and perform basic maneuvers, like hover or following waypoints. In this approach, we make use of the Neuroevolution of Augmenting Topologies (NEAT) algorithm which is aimed at creating the network structure and the weights in result of evolutionary computations. In order to evaluate fitness of individuals, we use physics based, realistic simulation engine Gazebo, where each individual controls a drone in a simulated environment. Our approach is aimed at using one of existing, popular protocols used to remotely control drones, and train ANNs able to imitate signals received from a radio controller operated by a human pilot. Thus, contrary to the most of other approaches, our autonomous controller cooperates with standard drone software. Our ultimate goal is to train ANNs able to control a real-world quadcopter and perform advanced tasks autonomously. Not only such ANNs should be able to perform the maneuvers correctly, but they should be small enough to transfer them into a quadcopter's limited memory. In this paper we report the first stage of our project - a successful development and deployment of the ANNs distributed training framework, and choosing the activation function for further research. [ABSTRACT FROM AUTHOR]

Copyright of Perspectivas de la Comunicación is the property of Journal Perspectivas de la Comunicacion, PhD in Communication, University of La Frontera and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A photonics-assisted binary/quaternary phase-coded microwave signal generator with fundamental/doubling reconfigurable carrier frequency applicable to digital I/O interfaces is proposed and has been verified by experiments. This scheme is based on a cascade modulation scheme, which is used to reconfigure fundamental/doubling carrier frequency and load the phase-coded signal, respectively. By controlling the radio frequency (RF) switch and the bias voltages of the modulator, the switching of the fundamental or doubling carrier frequency can be realized. When the amplitudes and sequence pattern of the two independent coding signals are set reasonably, binary or quaternary phase-coded signals can be realized. The sequence pattern of coding signals is applicable to digital I/O interfaces and can be directly generated through the IO interfaces of FPGA instead of an expensive high-speed arbitrary waveform generator (AWG) or other digital-to-analog conversion (DAC) systems. A proof-of-concept experiment is carried out, and the performance of the proposed system is evaluated from the aspects of phase recovery accuracy and pulse compression capability. In addition, the influence of residual carrier suppression and polarization crosstalk in non-ideal states on phase shifting based on polarization adjustment has also been analyzed. [ABSTRACT FROM AUTHOR]

The object of the study is to evaluate the quality of the frequency distribution of aircraft, which characterizes the effectiveness of radar surveillance of aircraft and determines the effectiveness of their control using radio signals. The frequency resolution of an aircraft is usually studied using the frequency ambiguity function for a coherent packet of radio pulses. However, there is a problem of estimating phase fluctuations, which is caused by the heterogeneity of the propagation of radio pulses, which affects the functioning of radar stations under different atmospheric conditions. A feature of the study is the development of theoretical provisions for the process of detection and radio control of single aircraft under the organized action of swarms. A normalized frequency ambiguity function is obtained, which takes into account the transformations caused by the radial motion of the aircraft. The calculations made it possible to estimate the range of changes in the frequency distribution under the condition of the additive effect of the internal noise of the radar receiver and the multiplicative effect of the cartelized phase fluctuations of the control radio signal. The statistical characteristics of phase fluctuations of radio pulses were obtained, under which their influence on the operation of radio technical control and radar systems is the most significant. Such statistical characteristics are important for the theory of radar location and of practical importance for the improvement of radio control of objects. Method is proposed for numerical evaluation of the influence of atmospheric disturbances on the frequency distribution function of aircraft during flight. This method is a convenient tool for analyzing the quality of the frequency distribution of a radar station in various conditions of radar surveillance of single aircraft in their organized swarm action. [ABSTRACT FROM AUTHOR]

The severity of the 2014–15 West African Ebola epidemic in Liberia was coupled with widespread misunderstanding of the virus among citizens and the proliferation of rumours. Rumour control during outbreaks is imperative to reduce the public's fears about a disease. In Liberia, a tracker system was developed to detect rumours as quickly as possible through SMS (short message service) text messaging. This study focused on assessing rumour circulation in newspapers and on radio and rumour control over time. It relied on a content analysis of SMS messages from the 'DeySay' tracker, print and audio communications of newspapers, and radio programmes, in the time frame between January 2014 and March 2015. The findings show that more rumours appeared in newspapers but were more likely to be overtly characterised as such on the radio. DeySay accurately predicted rumours before they appeared on the radio and in newspapers, supporting its usefulness in future health epidemics. [ABSTRACT FROM AUTHOR]

Radio waves are highly penetrating, non-ionizing, and cause minimal damage to surrounding tissues. Radio wave control of drug release has been achieved using a novel thermoresponsive copolymer bound to a superparamagnetic iron oxide nanoparticle (SPION) core. A NIPAM-acrylamide-methacrolein copolymer underwent a coil-to-globular structure phase change upon reaching a critical temperature above the human body temperature but below hyperthermic temperatures. The copolymer was covalently bound to SPIONs which increase in temperature upon exposure to radio waves. This effect could be controlled by varying input energies and frequencies. For controlled drug release, proteins were bound via aldehyde groups on the copolymer and amine groups on the protein. The radio wave-induced heating of the complex thereby released the drug-bearing proteins. The fine-tuning of the radio wave exposure allowed multiple cycles of protein-drug release. The fluorescent tagging of the complex by FITC was also achieved in situ, allowing the tagging of the complex. The localization of the complex could also be achieved in vitro under a permanent magnetic field. [ABSTRACT FROM AUTHOR]

Objective: This study investigates the role of individual differences in time perception on task performance during teleoperation with latency. Background: Long distance teleoperation induces latency, causing performance issues for the operator. Previous research demonstrated that individual differences in time perception predicted performance on a similar task, having participants navigate a radio controlled (RC) car around a track. This work extends the relationship into routes of varying course width to test whether differences in time perception predict movement over-/underestimation. Method: Participants completed a time estimation task and a route navigation task while experiencing latency. In the time estimation task, participants estimated the duration of multiple visual stimuli (2 s or less). In the route navigation task, participants moved a virtual cube across a route. Each trial varied in the amount of latency and the amount of horizontal clearance in the track (4–10 m for a 1.2-m-long/wide cube). Results: The results showed fairly consistent latency by time estimation and latency by clearance interaction effects on a wide set of trial-level variables, such as completion time, and action-level performance variables, such as time spent moving per move event. However, the results were not consistently in the predicted direction. Conclusion: Results suggest that clearance and timing affect performance across latency, at both the overall level (i.e., trial completion time) and at the action level (time spent moving). An open question remains as to how these contextual factors affect movement strategy selection. [ABSTRACT FROM AUTHOR]