Miracle-dz/UniFAR-FTUs huggingface dataset:
Lightning multi-band signal acquisition system based on software defined radio

Based on the software defined radio, a flexible data acquisition system is designed to receive wideband radiation produced by lightning discharges. USRP (Universal Software Radio Peripheral) N210 is used to collect lightning signals in three different frequency bands by different front daughter boards. The lightning signal is first converted to digital intermediate frequency signals and then reconverted to the original one. The data recording can be triggered once the lightning signal power reaches a certain threshold, and the absolute time of trigger can be obtained according to the GPS clock and NMEA (National Marine Electronics Association) code. All control modules are designed and programmed in the GNU Radio. Preliminary simulations and laboratory experiments were performed, and it can be verified that the system is feasible for lightning signal acquisition.
A Novel Global Maximum Power Point Tracking Method Based on Measurement Cells

Solar power generation has become a solution to mitigate the severe effects on the everyday higher prices of fossil fuels. Additionally, renewable energies operation -as solar- results in a non-polluting way to supply energy, being of special interest into highly contaminated cities and/or countries. The solar energy efficiency injection system is known to be high and mainly due to the power converters effectiveness, which is over of 95% for low and medium voltage. However, this efficiency is reduced when the solar array is partially shaded because traditional maximum power point tracking (MPPT) algorithms are not able to find the maximum power point (MPP) under irregular radiation. This work presents a new algorithm to find the global MPP (GMPP) based upon two MPPTs algorithms used regularly in uniform solar condition (USC), these are the Measuring Cell (MC) and the Perturb and Observe (P&O) methods. The MC ensures to find the surroundings of every local MPP (LMPP) faster and then choose among them the surroundings of the GMPP. Once the surroundings of GMPP are found, the P&O is used to get closer to the GMPP but reducing the DC voltage oscillation to zero hence overcoming the main issue of the P&O. Thus, the proposed algorithm finds the GMPP in two main steps and eliminates the oscillations around the GMPP in steady state, despite the utilization of the P&O. The algorithm is detailed mathematically, illustrated by means of a block diagram, and validated in simulated and experimental results.
Enhanced optoelectronic properties of UV-C light-emitting diode

We numerically analyzed proposed structure named as LED S2 in comparison to reference structure LED S1. In LED S2 we introduced undoped AlGaN and p-AlGaN layers between the electron blocking layer (EBL) and the p-GaN (hole injecting layer). The simulation finding shows proposed structure (LED S2) provide a better strategy for lowering electron overflow and improving hole strength. This enhancement in the properties is the result of maximum recombination of carriers (electron/hole) in the active region. Furthermore, the mismatch between the epi-layers on the p-side reduces, allowing holes to easily move towards the active region.
Transparent, Cascaded-Sheet Metasurfaces for Field Transformations

Integral equations are used to design transparent, cascaded-sheet, metasurfaces for arbitrary field transformations. Commonly used techniques such as the local periodicity approximation do not account for the inhomogeneity of the cascaded sheets. As a result, they impose restrictions on the separation between the sheets. In contrast, we use the governing integral equation to accurately design metasurfaces consisting of three cascaded inhomogeneous sheets separated by two dielectric spacers of arbitrary thickness. The integral equation, that is solved using the Method of Moments (MoM), accounts for all electromagnetic interactions between the inhomogeneous sheets. A design example is presented that shapes the field radiated from a line source into a collimated beam with a cosine tapered amplitude. The performance of the metasurface is verified using a commercial electromagnetics full-wave solver.
Integrated Energy System Resilience Assessment Based on Load Shedding Methodology

With the increasing awareness of environmental protection, integrated energy systems have gained an increasingly attention. However, the significance of resilience of integrated energy systems has been increasingly emphasized at a time when extreme events occur frequently. Therefore, this paper focuses on the concept of resilience. Firstly, the resilience evaluation index of integrated energy system is established. The index considers the damage frequency of each device in the system, the scale of load loss caused by failure and the time of the disaster. Subsequently, this paper gives the resilience evaluation process based on the simulation of the load loss of the system in a disaster. By improving the enumeration method, the accuracy of the overall resilience assessment when enumerating low-order cases is improved. The effectiveness of this method is tested in an actual case. Finally, this paper proposes a specific process for resilience strengthening of the system using this resilience assessment method and verifies that these methods can effectively improve the system resilience.
Harmonic Beam Steering Along Both the Cardinal Planes Using a Dual-polarized Space-Time-Coding Digital Metasurface

In this paper, a space-time-coding digital metasur-face is proposed for harmonic beam steering along both the cardinal planes. With respect to the harmonic frequencies, the metasurface steers a TE- (or y-) and TM- (or x-) polarized incident wave along xz- (ϕ = 0°) and yz- (ϕ = 90°) plane, respectively, upon reflection. To maintain the main lobe magnitude at the same level and the first side-lobe levels (SLL) 10 dB below the main lobe maximum for all the harmonic orders, an artificial neural network (ANN) routine is used to find out the required space-time-coding patterns for both the polarizations. A 1-bit coding digital metasurface is shown which can support the proposed idea.
Design and Optimization of Nano-Optical Isolators Based on Irregular Arrangements of Dielectric Rods

Design and optimization of efficient and compact nano-optical isolators based on irregular arrays of dielectric rods are presented. These designs allow electromagnetic waves to propagate in single direction and prevent them from propagating in the opposite direction. This way, high forward transmission is achieved, while the main source is protected from reflected waves. Effective optimization algorithms are integrated with the multilevel fast multipole algorithm (MLFMA), a fast and accurate full-wave numerical solver, to design efficient isolators composed of different arrangements of dielectric elements with controlled forward and backward transmissions.
Online Frequency Response Analysis of Multi-energy System Based on CloudPSS Real-time Simulation

With the increasing proportion of fluctuating power sources such as wind power and photovoltaic, multienergy systems have the risk of high and low frequency oscillations, and there is an urgent need to construct a wide-band response analysis tool for multi-energy systems. In this paper, a method for rapidly constructing electromagnetic transient (EMT) simulation models of multi-energy systems is first proposed. Then, a real-time simulation platform based on CloudPSS is built to realize the hardware-in-the-loop (HIL) simulation of a large-scale multi-energy system. In addition, an online frequency response analysis platform is constructed and stability analysis of the large-scale multi-energy system is performed. The results show that the system has the risk of oscillation near the frequency of 986 Hz, and the control strategy needs to be further adjusted to improve the stability of the system. The constructed platform can also be applied to the stability analysis study of other large-scale complex systems.
Infusing Big Data as part of a NEW Physics of Failure (PoF) Framework

Within the context of safety and reliability, NASA is building a framework to infuse artificial intelligence (AI), machine learning (ML), and “Big Data” with traditional Physics of Failure (PoF) approaches to transform space systems analysis at The National Aeronautics and Space Administration (NASA). This new approach aims to take advantage of the larger amounts of multivariate data being made available through increased use of sensors, model based engineering approaches, and other enhanced communications capabilities that provide far more detailed information about the non-linear dynamics of space systems than could ever be obtained before through typically small sample size laboratory experiments.
MAIDCRL: Semi-centralized Multi-Agent Influence Dense-CNN Reinforcement Learning

Distributed decision-making in multi-agent systems presents difficult challenges for interactive behavior learning in both cooperative and competitive systems. To mitigate this complexity, MAIDRL presents a semi-centralized Dense Reinforcement Learning algorithm enhanced by agent influence maps (AIMs), for learning effective multi-agent control on StarCraft Multi-Agent Challenge (SMAC) scenarios. In this paper, we extend the DenseNet in MAIDRL and introduce semi-centralized Multi-Agent Dense-CNN Reinforcement Learning, MAIDCRL, by incorporating convolutional layers into the deep model architecture, and evaluate the performance on both homogeneous and heterogeneous scenarios. The results show that the CNN-enabled MAIDCRL significantly improved the learning performance and achieved a faster learning rate compared to the existing MAIDRL, especially on more complicated heterogeneous SMAC scenarios. We further investigate the stability and robustness of our model. The statistics reflect that our model not only achieves higher winning rate in all the given scenarios but also boosts the agent’s learning process in fine-grained decision-making.
An Electronically-Controlled Frequency-Tunable Antenna Element Based on LTCC

A 12-layer liquid crystal antenna element is proposed based on the Low-Temperature Co-fired Ceramic (LTCC) technology. The antenna element consists of fractal patch antenna combined with a slot-coupled feeding form and electronically-tunable liquid crystal. Simulation results show that it can effectively work in the frequency range of 17 22 GHz with a center frequency of 19.25 GHz and its tunable−frequency range is more than 2.0 GHz. Also, the return loss is greater than 15 dB during the tuning process, indicating a very good impedance matching. By controlling the radiation of elements, the gain of array can be adjusted conveniently and efficiently.
Fabrication and electrical properties of grain-oriented 0.7Pb(Mg1/3Nb2/3)O3–0.3PbTiO3 ceramics

〈112〉 grain-oriented 0.7Pb(Mg1/3Nb2/3)O3–0.3PbTiO3 (PMN–0.3PT) piezoelectric ceramics with a degree of orientation of 0.35 have been produced from melt by a directional solidification method. The dielectric, ferroelectric, and piezoelectric properties were investigated, e.g., ert∼4800, tan δ<0.6%, d33∼1500–1600 pC/N, kt∼51%, and k33∼82%, some of these values are comparable to those of PMN–PT single crystals. The strain–electric-field curve with a maximum strain of 0.23% at a field of 22 kV/cm and well-saturated hysteresis loops with a Pr∼35 μC/cm2 were recorded. The results demonstrate that the directional solidification method is a promising technique to fabricate high performance grain-oriented PMN–PT ceramics.
An Energy Efficient Approach to Thermal Comfort Control in a VAV HVAC System

HVAC systems are major contributors to the energy consumption of a commercial building. Amidst rising environmental concerns globally, it is critical to identify easily implementable solutions to optimize consumption. A comfort control-based approach emerges promising, since it provides increased leverage over controlling parameters that are more economical (for instance, control air flow via fan speed as against control temperature via chilling water load) and still achieve required comfort levels. Additionally, it offers the user a more seamless experience by adjusting setpoints that are based on human sensation. This paper describes a novel approach to establish comfortable conditions via indices that truly reflect human perception, while optimizing energy consumption. A two-level control architecture is proposed, where the upper level determines the setpoints (temperature, humidity & air velocity) by optimizing energy loads and maintaining comfort index at user specified value. The lower-level architecture controls the MIMO system at the three specified setpoints using decoupled PI controllers, which conventionally was controlled for temperature only. The results show good independent control over the three setpoints with good leverage on fan load.
CaiRL: A High-Performance Reinforcement Learning Environment Toolkit

This paper addresses the dire need for a platform that efficiently provides a framework for running reinforcement learning (RL) experiments. We propose the CaiRL Environment Toolkit as an efficient, compatible, and more sustainable alternative for training learning agents and propose methods to develop more efficient environment simulations. There is an increasing focus on developing sustainable artificial intelligence. However, little effort has been made to improve the efficiency of running environment simulations. The most popular development toolkit for reinforcement learning, OpenAI Gym, is built using Python, a powerful but slow programming language. We propose a toolkit written in C++ with the same flexibility level but works orders of magnitude faster to make up for Python's inefficiency. This would drastically cut climate emissions. CaiRL also presents the first reinforcement learning toolkit with a built-in JVM and Flash support for running legacy flash games for reinforcement learning research. We demonstrate the effectiveness of CaiRL in the classic control benchmark, comparing the execution speed to OpenAI Gym. Furthermore, we illustrate that CaiRL can act as a drop-in replacement for OpenAI Gym to leverage significantly faster training speeds because of the reduced environment computation time.
Synergistic effect of total ionizing dose and electromagnetic interference in current reference circuits using scaling-down SOI technologies

This paper studies the behavior characteristics of the same structure circuits manufactured by three different technology nodes in the synergistic environment of total ionizing dose (TID) irradiation and electromagnetic interference (EMI). The experimental results show that the irradiation degrade the EMI immunity of the circuit with larger process feature size. Concurrently, the irradiation induces the abnormal startup problem of the circuit in the complex noise frequency domain environment, and the larger the technology feature size of the circuit can make the starting problem of the circuit worse.
A New H8 Inverter Topology With Low Common Mode Voltage and Phase Current THD for 3-φ Induction Motor Drive Applications

Common mode voltage (CMV) reduction in a traditional H6 (six switch) 3-φ inverter usually demands additional power semiconductors to avoid poor harmonic performance. However, apart from tending to the CMV related issues, these extra switches do not add any other capability to the inverter. To address this limitation, in this article, a novel H8 inverter configuration is proposed which not only reduces the CMV by 66.6%, the phase current total harmonic distortion (THD) is also improved. The proposed H8 inverter employs two additional power semiconductor devices along with the conventional H6 inverter in a manner that it can generate 15 space vectors (SV). By considering the CMV attribute of each SV, a unique sector configuration is proposed where the SV diagram is divided into 18 asymmetrical sectors and three distinct SV sequences are identified. A special pulsewidth modulation scheme is devised to operate the proposed topology to achieve reduced CMV and improved harmonic performance. A comparison study reveals that the proposed topology offers better phase current THD, low CMV, low losses, and low semiconductor requirement. Simulation and experimental results are included to justify the various claims.
Electromagnetic Interference of 5G Terminal Antenna to Equipment Inside Cabinet in Industrial Environment

With the development of communication technology, the use of fifth-generation (5G) terminals in industrial environment inevitably produces electromagnetic interference to equipment. In this paper, the E-field intensity inside the cabinet is discussed to evaluate the interference of the terminal to equipment. The cabinet and terminal antenna are modeled in the simulation. In addition, the key parameters of terminal location are found by simulations with the E-field intensity. The results with the utilized three terminal antenna models, sufficient distance shall be maintained at any height.
Ultra-wideband Magnetoelectric Dipole for 3G/LTE/Sub-6GHz 5G Applications

A new ultra-wideband magnetoelectric (ME) dipole antenna is proposed as a dual-polarized base station antenna for 3G, LTE and Sub-6GHz 5G wireless networks. Double layers of ME dipoles with different sizes are combined to expand the bandwidth, and the orthogonal placement of ME dipoles enables dual polarization radiation. Simulation results reveal that the proposed base station antenna achieves 133.3% fractional bandwidth and satisfying radiation characteristics, including high front-to-back ratio (FBR) (>14 dB), high cross-polarization levels (>20 dB), and stable gains about 5-10 dBi in 1-5GHz.
Metasurface Reflective Polarization Converter Based Dual-Band Circularly and Linearly Polarized Antenna

A dual-band circularly (at 0.78GHz) and linearly (at 2.45GHz) polarized antenna is proposed for radio frequency identification (RFID) and WIFI indoor positionings. The relevant standard for 779-787 MHz RFID is newly used in China, whereas the standard for 2.45 GHz RFID is ISO/IEC 18000-4. The antenna consists of microstrip-fed solt antenna (MFSA) and reflective polarization converter. This converter can transform a linearly polarized (LP) incident electromagnetic (EM) wave into its orthogonal LP reflection wave. The MFSA can achieve dual-band linearly polarized radiation. After loading the reflector, 3dB axial ratio (AR) bandwidths of 0.78–0.82 GHz is achieved.
Wideband Decoupling for Bandwidth Enhanced Dielectric Patch Antenna

A wideband decoupling method for dielectric patch (DP) antenna (DPA) is proposed in this paper. The air tunnel can not only incorporate TM10 and antiphase TM20 modes to expand the antenna bandwidth, but also make the port-to-port isolation (S21) flat in broadband. Furthermore, the two pairs of metal strips on the DPA help to achieve a balance between the mutual capacitive and inductive coupling, further improving wideband isolation. Meanwhile, it is worth noting that the radiation pattern can be stabilized during the decoupling process. Finally, the simulation result exhibits that the impedance bandwidth is 18.4% (4.97GHz-5.98GHz) and the in-band isolation is enhanced to more than 20dB.
Last advances in freehand sensing for mmWave imaging

This contribution presents the last developments of freehand systems for electromagnetic sensing, focusing on millimeter-wave (mmWave) freehand imaging systems. In particular, the impact of positioning errors in the quality of the obtained electromagnetic images is discussed, emphasizing the importance of using tracking systems that can be embedded in the freehand device. In addition, several challenges faced by freehand systems to achieve a higher scanning speed and a reduced computational burden towards fully autonomous portable systems are summarized.
ILC-based two-layer economic performance assessment and improvement strategy for large-scale industrial distributed MPC systems

When applied to large-scale industrial plants, the traditional linear quadratic gaussian (LQG) benchmark performance assessment method usually brings about unreachable economics, and its LQG curve dimension increases with the expansion of the system scale, which significantly aggravates the computation burden. To address various problems in the LQG benchmark method, an ILC-based two-layer economic performance assessment and improvement strategy are proposed and applied in large-scale distributed model predictive control (DMPC) systems. The presented strategy separates the whole operation time into multiple intervals during which the economic performance will be gradually improved and finally achieves its optimal. In each interval, the economic performance acquires its first promotion by the fixed variance obtained from the lower DMPC layer. The distributed ILC (DILC) method then provides the tuning parameters of each DMPC controller in the next period with the updating principle based on sensitivity analysis. The effectiveness of the presented strategy is verified via an improved Alumina continuous carbonation decomposition process compared to the former one.
Time Domain Analysis of an UWB Electrically Small Microstrip Patch Antenna

In this paper, the pulse transmission capability of an ultrawideband (UWB), coaxial probe-fed, electrically small, microstrip patch antenna has been examined. The designed antenna, which covers a 2:1 VSWR bandwidth of 54.94% (2.5-5 GHz), is subjected to a narrow Gaussian type pulse. A detailed investigation of the pulses, received by an identical antenna, in face-to-face and side-by-side orientations, has been performed in the far-field region. The study concludes that the proposed ESA is capable of transmitting narrow pulses, especially in face-to-face configuration, with good fidelity factors (> 0.9), and has uniform group delays over the frequency band of operation, rendering it suitable for various pulsed UWB wireless applications.
A Traveling-Wave Slotted Array Antenna Based on SIW at Ka-Band

In this paper, based on substrate integrated wave-guide (SIW), a 2×10 slotted waveguide antenna with six split ring resonators (SSR) is designed and simulated at Ka-Band to validate the slotted antenna. A series of 2×10 longitudinal slots etched on the top layer of SIW are employed as radiating elements at the Ku-band, while the SSRs etched on the bottom layer of the SIW are employed to filet electromagnetic wave. A one-to-two Wilkinson power divider feeds the antenna, which simplifies and compacts this antenna structure. The simulated results show that the bandwidth of the designed antenna for voltage standing wave ratio (VSWR) ＜2 is 2.5GHz at the center frequency of 32 GHz, and the side-lobe level is controlled lower than -18dB, and the realized gain is better than 14dBi. Due to its compact size, low side-lobe level and easy manufacturing, this proposed antenna may be applied to a Ka-band radar and communication system.