Miracle-dz/UniFAR-FTUs huggingface dataset:
Fundamental Trade-Off Between the Operating Frequency and Output Power Density in Linear-Mode Modulated SiC Photoconductive Switch

Due to insufficient carrier concentration in conventional radio frequency (RF) devices, there is a trade-off between the operating frequency and output power. While if photocarriers are generated through modulated light irradiation inside the bulk material, photoconductive semi-conductor switches (PCSS) might break through the limitation of carrier concentration and can generate modulated microwave signals that balance high power and high frequency. This article discussed a possible trade-off between operating frequency and output power density that similarly occurs in vanadium compensated semi-insulation (VCSI) 4H-SiC PCSS. Through finite element analysis, two methods of changing electrode gap and V concentration were proposed to select device design schemes under specific frequency and output power requirements. At the V concentration of 2.3 × 1017 cm−3, the device can output microwave signals with a peak output power density of approximately 219 kW/mm at a 20 kV bias voltage.
A Full Analytical Prediction Method of Vibration and Noise for Single Cylindrical Shell Model on PMSM

This paper analyzes the vibration and noise levels of permanent magnet synchronous motor (PMSM). Firstly, an equivalent single cylindrical shell model of motor is established, which considers the influence of the enclosure and windings. Then, a full analytical model is developed to predict the radial vibration displacement and noise under no-load condition, and these results are confirmed by simulation and experiment. In addition, the mutual prediction scheme between no-load and load is presented, and the specific order noise with large amplitude is further obtained.
A 94-GHz Down-Conversion Mixer with 15.8-dBm IIP3 Based on Multiple-Gate Transistor Structure

This paper presents a 94 GHz down-conversion mixer with high linearity in a 40-nm CMOS process. A multiple-gate transistor (MGTR) structure is used in the gm stage of the Gilbert cell to improve its linearity. In addition, a PMOS cross-coupled pair is adopted for providing negative impedance and current bleeding. Meanwhile, a coupled line based matching network is introduced between the gm stage and the switch stage to resonate parasitic capacitance and improve the noise and gain performance. The proposed mixer exhibits a conversion gain of 2.4 dB and a NF of 16.3 dB. The simulated IIP3 is 15.8 dBm and IP1dB is −3.8 dBm. The mixer draws 11.3 mA from a 1.1 V supply voltage excluding the LO buffer which consumes DC power of 14.5 mW.
A seasonal climatology of the Melbourne 1965-1975 ozonesonde record

A seasonal climatology of the 1965-1975 Melbourne ozonesonde ozone profile record is presented, spanning a period when minimal stratospheric ozone chemical depletion existed and prior to adequate satellite ozone profiling. Results are presented as monthly isentropic weighted means of ozone mixing ratio and partial pressure, with associated uncertainties, plotted against potential temperature and altitude. Corrections for pump inefficiency and referencing to the current ozonesonde type are included. The general seasonal and altitudinal features of the results are consistent with our current understanding of ozone variations in the southern mid-latitudes. These results are of value to atmospheric chemical and climate change models.
Effects of a Comprehensive Fault Current-Limitation Approach with SFCL on DC Pilot Protection

Suppressing DC fault current within the safety margin is critical for a high-voltage direct-current (HVDC) system. Our research group has proposed a comprehensive fault current-limitation (CFCL) approach, which uses the coordination of the converter controller and superconducting fault current limiter (SFCL). This paper studies the influence of the CFCL approach on DC pilot protection. The theoretical presentation of the CFCL method and DC pilot protection in a modular multilevel converter (MMC)-based HVDC is conducted, and the function of coordinating the virtual impedance and resistive SFCL to the DC fault current is analyzed. Using MATLAB, the digital model of a 320 kV MMC-HVDC with the CFCL method and DC pilot protection is constructed, and a metallic DC ground fault is imitated to test the system’s transient behaviors. From the simulation outcome, the CFCL approach can well guarantee DC fault detection speed without affecting the correct operation of the DC pilot protection in the MMC-HVDC system.
Manejo quirúrgico del hemangioma cavernoso orbitario.: caso clínico

espanolCaso Clinico: Mujer de 48 anos, con antecedente de ambliopia en ojo derecho (OD) que consulta por disminucion de agudeza visual progresiva en OD. En la exploracion del OD destaca: agudeza visual mejor corregida (AVMC) de 0,4 (1,0 en ojo izquierdo OI), limitacion a la abduccion asociada a diplopia en dextroversion, exoftalmometria de 19 mm (14 mm en OI) e ingurgitacion venosa retiniana con pliegues maculares. Se solicita resonancia magnetica (RM) evidenciandose masa intraconal bien delimitada susceptible de hemangioma cavernoso orbitario (HCO). Se realiza exeresis de lesion intraconal a traves de orbitotomia lateral (OL) derecha, confirmandose el diagnostico de HCO mediante anatomia patologica. En la actualidad (2 meses tras cirugia) presenta en OD: AVMC 1.0, paresia de musculo recto externo (MRE), exoftalmometria de 15 mm y resolucion incompleta de la ingurgitacion vascular y de los pliegues coroideos. Discusion: Diversos abordajes quirurgicos han sido descritos para la reseccion del HCO. La OL a traves de acceso transcutaneo parece una tecnica segura y eficaz para la localizacion del HCO intraconal y su exeresis, tecnica utilizada en nuestro caso clinico EnglishCase report: 48-year-old woman with medical history of amblyopia in her right eye (RE) consulted for progressive decrease in visual acuity in RE. The RE exploration shows: best corrected visual acuity (BCVA) of 0.4 (1.0 in the left eye), abduction limitation associated with diplopia in dextroversion, exophthalmometry of 19 mm (14 mm in contralateral eye) and retinal vein engorgement with macular folds. Magnetic resonance is requested and an intraconal, well-limited, cavernous-hemangioma-suggestive (CH) mass, is found. Intraconal mass excision was performed by lateral orbitotomy (LO) in the right side, confirming CH diagnosis by pathological anatomy. Nowadays (2 months after surgery), RE shows: BCVA 1.0, external rectus muscle palsy, exophthalmometry 15 mm and incomplete resolution of vascular engorgement and choroidal folds. Discussion: Several surgical approaches have been described for CH resection. Transcutaneous LO appears to be a safe, effective technique for intraconal CH location and excision: such was the technique used in our clinical case.
A new Interleaved Full-Bridge Converter for AC battery

Home battery storage systems using Second-life time batteries (SLBs) are of recent research interest for resilient homes. The AC Battery is chosen for this application due to its flexibility, in which the Interleaved Full Bridge (IFB) converter is studied in this paper for the Power Correction Factor (PFC) stage. The pulse width modulation and control strategy are introduced for the IFB converter in this research. To verify the operation and the feasibility of the proposed structure in the grid-tied mode, a real-time simulation is carried out with the results meeting a good agreement with the theoretical analyst.
Mean Antarctic Circumpolar Current transport measured in Drake Passage

The Antarctic Circumpolar Current is an important component of the global climate system connecting the major ocean basins as it flows eastward around Antarctica, yet due to the paucity of data, it remains unclear how much water is transported by the current. Between 2007 and 2011 flow through Drake Passage was continuously monitored with a line of moored instrumentation with unprecedented horizontal and temporal resolution. Annual mean near‐bottom currents are remarkably stable from year to year. The mean depth‐independent or barotropic transport, determined from the near‐bottom current meter records, was 45.6 sverdrup (Sv) with an uncertainty of 8.9 Sv. Summing the mean barotropic transport with the mean baroclinic transport relative to zero at the seafloor of 127.7 Sv gives a total transport through Drake Passage of 173.3 Sv. This new measurement is 30% larger than the canonical value often used as the benchmark for global circulation and climate models.
Decision-making strategy for multi-agents using a probabilistic approach: application in soccer robotics

The efficient coordination of soccer robots is a complex topic because there are numerous possible scenarios in the game, and the state of the robots can change rapidly. It requires the robot to be able to analyze and make decisions in a short time. In this article, we first use Dec-POMDP to describe the actions and states of the soccer robot team. Secondly, we introduce a probabilistic approach so that the robots can quickly make decisions corresponding to specific situations. More specifically, we present a method for calculating and evaluating the expected points corresponding to each particular action for each robot. The robots then choose the actions with the highest expected points. Finally, we have developed a simulator based on the digital twin approach to verify the proposed strategies on simulation models and implement these strategies rapidly on real robots.
Efficient Co-Design Methodology combinig Fast and Accurate System-level Simulations with Transistor-level Characterization

The Charge-Pump PLL (CP-PLL) stays one of the most popular circuit topologies used for frequency synthesis. Because of its mixed-signal nature, no established linear theory allows an exact description of its behavior, making its design challenging. In this paper an efficient design approach of the CP-PLL is presented achieving accuracy and time efficiency while considering nonlinear and non-ideal effects. A very efficient event-driven simulation model is combined with a CMOS-based design approach. The extracted macroscopic parameters are used at the behavioral level in order to allow a very fast but accurate closed-loop simulation, leading to a robust top-down and bottom-up co-design methodology.
A 21–27 GHz LNA-Mixer in a 180 nm SiGe BiCMOS Process

This article presents a 21–27 GHz LNA-Mixer used for radar receiver in a 180 nm SiGe BiCMOS process under 1.8 V voltage supply. The LNA incorporates a single-stage cascode topology with capacitive feedback and neutralized capacitors to balance gain, noise, and linearity. Considering the low voltage supply, the mixer adopts a passive double-balanced structure, down-converting the RF signal to 1 MHz. A transformer is utilized for the interstage impedance matching between LNA and Mixer. The DC biasing condition is provided by a Proportional To Absolute Temperature (PTAT) current source. Designed at the center frequency 24 GHz, the proposed LNA-Mixer achieves −20.9 dBm IP1dB, 31.3 dB voltage gain, 4.1 dB noise figure under 36.0 mW power consumption.
CDS Free Frame Differencing Event Vision Pixel with Lateral Overflow Capacitor for Dynamic Range Extension

This paper reports on a redesign of an event pixel by frame differencing with a lateral overflow capacitor for dynamic range extension. In the first prototype, the inclusion of an inpixel correlated double sampling (CDS) and an algorithm for dynamic range extension resulted in a large pixel area, with a $32 \mu \mathrm{m}$ pitch in 180 nm CMOS technology. This paper studies a CDS free version of our former pixel through post-layout simulations. The pixel pitch is shrinked to $22 \mu \mathrm{m}$, power consumption is lowered and speed is preserved.
Deep Clustering Based Latent Representation for IoT Malware Detection

The Internet of Things with a billion connected devices can generate a huge amount of data daily. This poses challenges to security tasks (i.e. identifying IoT malware). Our previous studies used analytic techniques to reduce the data size and extract valuable information. Currently, clustering is a key technique for many data-driven applications, and it has been widely studied with different distance functions and algorithms. One research direction is to use representation learning for clustering. This research proposes a combination of Deep Clustering AutoEncoder (DCAE) with anomaly detection algorithms for an end-to-end anomaly detection framework. The DCAE maps the data from the original space to a lower-dimensional latent space, where it iteratively minimizes the clustering loss. Then, the output of DCAE is fed to algorithms such as Isolation Forest (IF), $K -$nearest Neighbors (KNN), Local Outlier Factor (LOF), and One-class Support Vector Machine (OCSVM) for identifying anomalies. The proposed model is evaluated on nine recent devices in the N-BaIoT dataset and measure their performance. The experimental results show that the new latent representation improves the IoT outlier detection methods significantly. The model’s time efficiency is also recorded to assess its suitability for practical applications.
Wideband Four-Port 3-D Interconnection Based on SIW for Multi-Port Connection

In this paper, a wideband 3-D interconnection based on Substrate-Integrated Waveguide(SIW) is proposed. Its four ports which contain two input ports and two output ports constitute two isolated transmission paths. Compared with the previous vertical interconnection, the number of dielectric is less. And the performance of amplitude and phase consistency of the two paths are good in wideband, which can satisfy the demand of more complex multi-port connections at high frequency with low loss. The simulation results shows the transmission coefficient is better than 0.4dB and the phase error is ± 15° in 27-33GHz. The 8 × 8 connection consist of several 3-D interconnections is established. More ports and the different arrangement of input ports and output ports enables the connection to satisfy the demand of more complex and irregular connection in beamforming networks.
Thermal Performance Investigation of a High-Current & High-Power Density GaN-Based Motor Drive for All Electric Aircraft Applications

Integration of electric machine, drive system, and cooling system in a single structure was proposed as a solution to meet the high power density and efficiency requirements in aviation applications. From the drive perspective, both the efficiency and power density are highly dependent on the switching device selection. Thus, semiconductors with small footprint and low on-state resistance are desirable. Integrating the power converter with the electric machine limits the available space, thus the PCB should be designed accordingly. Considering the space constraint in addition to the efficiency and power density requirements for such an application, the thermal performance of the designed converter is pivotal. In this paper, the thermal performance of a high-current & high-power density GaN-based motor drive is evaluated. At first, using the PLECS software, the performance of the power converter was simulated at rated load conditions. Using PLECS’s thermal library, the characteristics of the cooling system are modeled. Based on the simulation results, the cooling system configurations that can satisfy the constraints of the drive system are determined. Finally, the performance of the drive module was evaluated through DC and AC testing.
Investigating the Stability of a DC Shipboard Microgrid protected with Solid-State Circuit Breaker

DC microgrids represent a valuable solution for the realization of shipboard power systems. However, protection of dc microgrid is challenging: the absence of zero crossing of dc currents and the fast response of new technologies of energy storage system such as supercapacitor and batteries introduce strict requirements on the circuit breaker performances, making the conventional electro-mechanical circuit breaker not suitable for these applications. For these reasons, the solid-state circuit breaker is one of the most promising solutions. However, this component requires the presence of a current-limiting inductor, for limitation of the maximum value of fault current, whose effect in the normal operation of the system has not been addressed in literature. This work aims to identify, through an analysis of the impedance ratio in the point of coupling and real-time simulations, the presence of a potential resonance in the dc-bus of a notional dc microgrid. Different study cases have been considered, varying the value of the inductive fault current limiter, demonstrating the need to further investigating this phenomenon.
A Wide Beam and Circularly Polarized Antenna with Parasitic Element

A circularly polarized wide beam microstrip patch antenna is proposed for the low earth orbit(LEO) satellite communication. The proposed antenna consists of a radiation patch, a parasitic metal and the feed network. Wide beam radiation patterns can be obtained from 27.5 to 30.5GHz by applying a square ring parasitic elements around the radiation patch. The 3 dB beamwidth of the antenna in the 2-D space is in the range between 93° and 104°. The simulated results show that S11 is less than -10dB at the frequency range of 25.1-31.4GHz and axial ratio (AR) is less than 3dB at the frequency range of 26-30.8GHz.
Design and Fabrication of Non-Volatile Direct Heating RF High-Speed Switch Matrix Based on GeTe Phase Change Material

In this work, a 2 × 2 non-volatile direct heating RF switch matrix based on GeTe phase change material was innovatively designed and fabricated based on multilayer lithography process. The pulsed laser deposition-derived phase change materials (PCM) of GeTe exhibited high crystalline quality with no impurities observed. The GeTe-based RF switch can achieve “On” and “Off” operations under 300 ns electrical pulse of 4.9 V and 7.1 V voltage, respectively. Based on the fast response of the PCM switch, the 2 × 2 matrix was designed and fabricated. The measured S-parameter of the matrix demonstrate that the insertion loss of the two RF phase-change switch units in the “On” state are more than 0.63 dB, while the isolation of the two RF phase-change switch units in the “Off” state are less than 20.3 dB over the range of DC-35 GHz. This work provides novel ideas for the design of high-speed RF switches and matrices, the proposed GeTe thin film phase change switch matrix offers an effective approach for advanced large frequency range, multi-channel high-speed switching.
Search Box System to Improve User Interaction in Knowledge Graph Searches: A Solution for Users Without Expert Skills

Knowledge graphs enable semantic search in a variety of information systems. Some collaborative and public ones have existed for more than a decade. That is the case of Wikidata, one of the most popular knowledge bases today. It contains a graph of entities that has been growing since 2012 to host more than 94 million items. Currently, the exploration of data in Wikidata is a tedious task, especially for inexperienced users: it requires users to go deep into entities and perform a large number of clicks and searches of property names. Our goal is to allow nonexpert users who want to enter new data in Wikidata to be able to examine its ontologies in an agile way so that they can know whether a particular statement is present in the graph. To this end, we propose a new search box for Wikidata, which allows an exploratory search based on chained entities without having to navigate through pages. It is based on the real-time classification of the information that the user enters in the search box and the dynamic generation of suggestions based on the exploration of entities and relationships. A quantitative analysis is performed comparing how many iterations a user needs to perform a set of popular searches with our proposal and standard Wikidata search. The results suggest that interaction can be reduced by about 43%.
Wideband Compact Vivaldi Antenna For Millimeter-Wave Applications

In this paper, a compact Vivaldi antenna fed by double ridged substrate integrated waveguide (DRSIW) is presented for millimeter-wave (mm W) wireless applications. Compared to the Vivaldi antenna fed by substrate integrated waveguide (SIW), the presented Vivaldi antenna element owns a much more compact lateral size, measuring only 0.52 $\lambda_{0}(\lambda_{0}$ denotes the wavelength in air at 40GHz). In addition, for the sake of introducing dual-layers metal strip matching structure, broadband impedance bandwidth ($\vert S_{11}\vert <$ -lOdB) of more than 70% (24.17GHz-55GHz) can be achieved, which makes the proposed antenna a promising candidate at mm W frequencies.
Coherent Integration and Detection for Extended Targets in Traffic Scenes

This paper intends to address the problem of detecting high speed and maneuvering extended target in wideband radars with the idea of coherent integration (CI). Due to the extended target energy spillover may occur in adjacent range bins, along with the shadowing effect of contiguous scattering centers (SCs), the robust detection of weak extended target is a challenging problem. Both of the range migration (RM) effect and Doppler frequency migration (DFM) will be introduced in target returns due to high maneuverability. To address these problems, two CI methods called modified Keystone transform (MKT) and modified Radon Fourier transform (MRFT) are proposed for high speed and maneuvering extended target detection. To mitigate the disturbance caused by DFM, the phase compensation with two-order motion parameter is constructed to prevent energy dispersion in the Doppler frequency domain. Then, the Keystone transform (KT) and Radon Fourier transform (RFT) are applied for range walk correction, respectively. The effectiveness of the proposed methods is validated by numerical simulations of four typical traffic scenes.
ANN-Powered Reinforcement Learning-Based Analog Circuit Optimization

One of the challenging problems that Electronic Design Automation (EDA) dealing with is automatic circuit sizing, which is basically optimizing circuits to meet various performance metrics, such as gain, bandwidth, and reliability. Recently, it has been shown that Reinforcement learning (RL) has the potential to revolutionize the circuit sizing and improve the efficiency of the existing algorithms. To this end, several RL-based approaches have been proposed in the literature; however, they suffer from expensive simulations performed in every steps of optimization that degrades the efficiency in terms of execution time. To overcome this problem, we propose a novel RL-based optimization approach, where we empower the RL with artificial neural network (ANN) that substitutes the simulation environment, thus avoiding expensive SPICE simulations. According to the synthesis results, the proposed tool can achieve more than $6 \times$ runtime speed-up compared to the simulation-based approach without sacrificing the accuracy.