Miracle-dz/UniFAR-FTUs huggingface dataset:
Performance Evaluation of High-Power SiC MOSFET Modules in Comparison to Si IGBT Modules

The higher voltage blocking capability and faster switching speed of silicon-carbide (SiC) <sc>mosfet</sc>s have the potential to replace Si insulated gate bipolar transistors (IGBTs) in medium-/low-voltage and high-power applications. In this paper, a state-of-the-art commercially available 325 A, 1700 V SiC <sc>mosfet</sc> module has been fully characterized under various load currents, bus voltages, and gate resistors to reveal their switching capability. Meanwhile, Si IGBT modules with similar power ratings are also tested under the same conditions. From the test results, several interesting points have been obtained: different to the Si IGBT module, the over-shoot current of the SiC <sc>mosfet</sc> module increases linearly with the increase of the load current and it has been explained by a model of the over-shoot current proposed in this paper; the induced negative gate voltage due to the complementary device turn-<sc>off</sc> (crosstalk effect) is more harmful to the SiC <sc>mosfet</sc> module than the induced positive gate voltage during turn-<sc>on</sc> when the gate off-voltage is –6 V; the maximum <italic>dv</italic>/<italic>dt</italic> and <italic>di</italic>/<italic>dt</italic> (electromagnetic interference) during switching transients of the SiC <sc>mosfet</sc> module are close to those of the Si IGBT module when the gate resistance is larger than 8 Ω but the switching loss of the SiC <sc>mosfet</sc> module is much smaller; the switching losses of the Si IGBT module are greater than those of the SiC <sc>mosfet</sc> module even when the gate resistance of the former is reduced to zero. An accurate power loss model, which is suitable for a three-phase two-level converter based on SiC <sc>mosfet</sc> modules considering the power loss of the parasitic capacitance, has been presented and verified in this paper. From the model, a 96.2% efficiency can be achieved at the switching frequency of 80 kHz and the power of 100 kW.
A Method for Improving Physical Layer Security in Visible Light Communication Networks

In this paper, a method is proposed for improving the physical layer security for indoor visible light communication (VLC) networks with angle diversity transmitters. An angle diversity transmitter usually consists of multiple narrow-beam light-emitting diode (LED) elements with different orientations. Angle diversity transmitters are suitable for confidential data transmission, since data transmission via narrow light beams can effectively avoid the leakage of messages. In order to improve security performance, protection zones are introduced to the systems with angle diversity transmitters. Simulation results show that over 50% performance improvement can be obtained by adding protection zones.
A Digital LDO With Co-SA Logics and TSPC Dynamic Latches for Fast Transient Response

This letter presents a coarse-fine dual-loop digital low-dropout regulator (DLDO), with combined synchronous and asynchronous logics, designed and measured in a 28-nm bulk CMOS. We adopt a react-then-write two-step logic in the coarse loop for faster transient response. To further shorten the loop latency, we employ true single-phase clock dynamic latches in the coarse loop, and a self-biased continuous-time comparator for voltage droop detection. The proposed DLDO architecture achieves an FoM of 0.59 ps, with a load range of 5–25 mA under a 600-mV supply.
Simple Controller Configuration for Decentralized Parallel Operation of Inverters

In this paper, a simple controller configuration for the decentralized parallel operation of single-phase inverters in stand-alone ac supply systems is proposed. The configuration is designed considering the unavailability of the filter capacitor voltage and grid current information to the controller. Due to the unavailability of voltage information, internally estimated voltage references and the measured value of the converter-side inductor current are used for the calculation of the active and reactive power. Frequency and voltage droop characteristics are used, and hence, communication is not required. The operation of the inverter at the reference voltage magnitude and frequency is achieved by the direct control of the modulating wave. Therefore, inability to implement closed loops caused by the absence of certain voltage and current information is mitigated. The proposed controller has the provision for protection of switching devices during overcurrent situation. The accuracy and feasibility of the proposed controller are validated using the simulation and experimental results.
Reasonable Grasping Based on Hierarchical Decomposition Models of Unknown Objects

Reasonable grasping for unknown objects is an interesting and important problem for autonomous robots in unstructured environment. Current grasping methods for unknown objects mostly focus on precision and stability. Until now there are few specific studies or reports describing reasonable grasp of unknown objects for service robots such as home service robots and nursing robots. In the paper we proposed a reasonable grasping method for unknown objects based on hierarchical decomposition point cloud models using a vision sensor. As a complex task, vision-based grasp is composed of a series solution of a mixture of subproblems. Therefore, we adopt an improved superquadrics fitting algorithm with the improved cuckoo search strategy (S-ICS) to achieve restoration and segmentation of incomplete point cloud data of unknown objects in a single visual angle. Then a reasonable region decision method based on hierarchical decomposition models is proposed to evaluate the reasonableness of grasped positions of unknown objects. Finally, we use a simulation to verify the effectiveness of the proposed method. Moreover, we also perform an extensive real-world grasping experiment on a set of unknown objects in daily use. The results also verify the effectiveness of our approach.
Performance Analysis of User Pairing in Cooperative NOMA Networks

In this paper, we study the coverage probability and average data rate of user pairing in cooperative non-orthogonal multiple access (NOMA) networks. With fixed locations of the source and typical user, the candidate users for pairing follow homogeneous Poisson point process. Considering the geometric distance between nodes, close-to-user pairing (CUP) and close-to-source pairing (CSP) schemes are investigated with the near user acting as half-duplex relay or full-duplex (FD) relay. Lower bounds on the coverage probability and average data rate are approximately obtained using stochastic geometry and Gaussian–Chebyshev quadrature. Numerical and simulation results corroborate the accuracy of the analytical results and reveal that CUP-based cooperative NOMA outperforms CSP-based cooperative NOMA in terms of the data rate performance. With typical user close to the source, CUP-based FD NOMA is the best transmission scheme (among CUP-based and CSP-based cooperative NOMA, non-cooperative NOMA, and OMA schemes) that maximizes the sum data rate and the minimum user rate.
A PFC Single-Coupled-Inductor Multiple-Output LED Driver Without Electrolytic Capacitor

In order to lower the system cost and reduce the form factor, single-inductor multiple-output (SIMO) converters are intensely developed for on-chip dc–dc converters and offline light emitting diode (LED) drivers. However, existing single-stage power factor correction (PFC) SIMO LED drivers are usually designed with electrolytic capacitors, leading to a short-life span and limited range of operation temperature. In this paper, based on a single dual-winding coupled inductor, a SIMO LED driver with PFC function is proposed without the requirement of electrolytic capacitors, where a small storage capacitance is used to actively decouple the ac and dc input powers. Compared with previous works, the proposed PFC SIMO LED driver has some additional benefits, including a smaller line filter, multiple output currents without double line frequency ripple, and a faster output regulation. With appropriate control strategy, an independent output regulation can be achieved for each output channel. Meanwhile, to improve the converter efficiency, the energy flow of the converter is optimized with an inductor current programming technique. Finally, the proposed electrolytic capacitorless PFC SIMO LED driver is developed, designed, tested, and compared with a single-stage SIMO design without active power decoupling.
Polarimetric Diffuse Scattering Channel Measurements at 26 GHz and 60 GHz

Fifth generation (5G) networks will utilise the large bandwidth available in millimetre wave (mmWave) frequency bands up to 100 GHz in order to meet the ever-increasing high data rate demands. Efficient communications system design for such networks requires a thorough understanding of the propagation properties of the electromagnetic signals at such high frequencies. This paper presents the results of a polarimetric channel measurement campaign at 26 GHz and 60 GHz showing that diffuse scattering can be a dominant propagation mechanism for mmWave links. The use of a wide bandwidth provides a detailed insight into the multipath structure of the channel. It is shown that in a diffuse scattering scenario, nearly co-incident signals create small scale fading that affects the flatness of the channel significantly even when directional antennas are used. This also results in large co-to-cross polarisation ratio (XPR) variations across the channel bandwidth.
A Study of Capsule Endoscopy Orientation Estimation Using Received Signal Strength

Comprehensive study of wireless communication for ingestible electronics is a very challenging task. To initiate the study on wireless capsule endoscopy, an innovative immersive platform containing an enhanced 3D human body model has been developed. This platform allows for flexible placement of a capsule inside the gastrointestinal (GI) tract and multiple receivers around the abdomen area. It is shown that any directionality (or equivalently null) in the antenna radiation pattern can be exploited to sense changes in the orientation of the capsule through observation of the S21 vector at a set of on-body receivers. Two methodologies i.e. complex cross-correlation and Minkowski distance were used to assess capsule orientation estimation with respect to a reference position. The study was performed within the Ultra-Wide Band frequency range as this technology is considered to be an attractive candidate for the next generation of wireless capsule endoscopy.
Automatic Extraction of Emergency Response Process Models From Chinese Plans

Emergency plans can be regarded as the effective guidance of hazard emergency responses, and they include the textual descriptions of emergency response processes in terms of natural language. In this paper, we propose an approach to automatically extract emergency response process models from Chinese emergency plans. First, the emergency plan is represented as a text tree according to its layout markups and sentence-sequential relations. Then, process model elements, including four-level response condition formulas, executive roles, response tasks, and flow relations, are identified by rule-based approaches. Finally, an emergency response process tree is generated from both the text tree and extracted process model elements, and is transformed to an emergency response process that is modeled as business process modeling notation. Extensive experiments on real-world emergency plans demonstrate that the proposed approach is capable of extracting emergency response process models that are highly consistent with both the manually extracted models and the textual plans.
Virtual Learning Object for Teaching Processes in Dental Prosthesis Modeling Recreating Digital Models

"Corporación Universitaria Autónoma de Nariño (AUNAR) Villavicencio" offers Dental Mechanics as a career to Llanos Orientales region (middle est) of Colombia. Currently, the creation of dental prostheses is an artisan work made by students without to implement digital processes. Industry advances are focused on computer-aided design and computer-aided manufacturing (known as CADCAM) for the digital fabrication of dental pieces, improving times, costs and product quality. Is very important to give tools to the student that allow them understand new techniques to create the dental rehabilitations. For this reason an interinstitutional research work is developed between the Corporación Universitaria Autónoma de Nariño AUNAR with the programs of Dental Mechanics and Computer Engineering and the "Corporación Universitaria del Meta UNIMETA" with the participation of the Systems Engineering program, seeking the analysis and operation of the process CADCAM. For this work, photogrammetry techniques are used to capture models of dental works elaborated by the students of dental mechanics, then they are processed in three-dimensional modeling software and subsequently the models are printed on 3D printers. As a result of the research, a virtual learning object is developed that allows students of the first semesters of the Dental Mechanics program to learn the results of dental work with 3D models prepared by students in the last semester.
Non-Iterative MDS Method for Collaborative Network Localization With Sparse Range and Pointing Measurements

Multi-agent localization is a basic requirement for many networked applications. The particular application to swarming unmanned aerial vehicles (UAVs) or munitions requires spatial coordination of agents, including the ability to assume and maintain a prescribed flight formation. An in-flight awareness of network morphology and node location is therefore needed. While global navigation satellite systems offer an attractive solution, signal occlusion, spoofing, and jamming present unacceptable vulnerabilities—particularly for mission-critical operations. Alternative network localization methods using inter-agent radio frequency ranging and Angle of Arrival have been well studied over the past 15 years, but existing algorithms are not well suited to fast-moving networks. Iterative methods tend to converge slowly. Faster noniterative multi-dimensional scaling (MDS) methods for range, bearing, or vector measurements have also been formulated. However, these MDS methods generally require the full pairwise inter-agent measurement matrix—placing a severe requirement on swarm connectivity and leading to low tolerance for missing or badly estimated measurements. Even vector-based MDS, which incorporates both range and direction constraints, is shown here to require 4-vertex connectivity to achieve perfect localization. Results from rigidity theory, however, suggest that a lower connectivity threshold should be sufficient to guarantee a unique configuration (up to translation and rotation). In contrast, our proposed “vertex resequencing” and “edge resequencing” techniques further lower the vertex-connectivity threshold to 3 and 2, respectively. These localization techniques, which extend vector-based MDS with Nyström approximation, prescribe a graph-based kernel sampling scheme and weighted coordinate reconstruction that suppress the effect of missing measurements.
Operation Cost Minimization for Base Stations With Heterogenous Energy Supplies and Sleep-Awake Mode: A Two-Timescale Approach

In this paper, we study an energy cost minimization problem in cognitive mobile wireless networks, where base stations (BSs) are powered by hybrid energy sources including external power grids (PG), harvested renewable energy (RE), distributed local generators and energy storages. Based on sleep mode techniques, idle BSs can be switched to an energy-saving mode to cut down unnecessary expenditure. We formulate the problem into an optimization programming to achieve optimal decisions for energy scheduling and sleep control. By adopting a two-timescale approach, we implement the power scheduling and data transmission in time slots and the BSs sleep-awake mode in time frames (each time frame consists of multiple time slots) to avoid the overheads for frequent sleep/awake mode switches. Based on the Lyapunov technique, we further propose a close-to-optimal algorithm which only requires mean energy price of PG in each time frame instead of the exact future information about stochastic inputs (e.g., the amount of RE harvesting and user demand for data traffic). The proposed algorithm can achieve approximately minimal energy cost and ensure the stability of workload and battery queues. We present theoretical analysis as well as numerical simulations to demonstrate the performance of the proposed algorithm.
Improved Handover Signaling for 5G Networks

Mobility management is a critical component for any new wireless standard to be ubiquitous. While 4G-LTE and prior wireless standards utilized vendor specific hardware and software on which mobility management (MM) functionality was implemented, recent 5G architecture releases by 3GPP indicate a complete departure from the same. 3GPP in release 14 and the upcoming release 15 has stressed upon the utilization of Software Defined Networking (SDN) and Network Function Virtualization (NFV) as the drivers of 5G technology. Consequently, new challenges related to MM and specifically handover management will be encountered owing to the inter-working setup between the 5G Next-Gen Core (NGC) and the Evolved Packet System (EPS) core. In this paper, we exploit the SDN to enhance the signaling of the HO methods proposed by 3GPP. Although the proposed approach can be applied to any HO method, in this paper we specifically evaluate the scenario wherein a dedicated interface between the Mobility Management Entity (MME) in the EPC and the Access and Mobility management Function (AMF) in the 5G NGC, i.e., N26 as specified by 3GPP, is non-existent. Such a scenario is reasonable during the initial deployment phases of 5G networks. We show that the proposed mechanism is efficient as compared to the 3GPP handover strategy in terms of latency, transmission and processing costs.
Driver Drowsiness Detection Based on Eye Analysis

Safe car driving has become a priority in everyday life. The main reason for designing a real time system which monitors the state of the driver’s eyes is related to a decrease in car crashes that will benefit millions of people around the world. This work proposes a method to detect and to monitor the eyes of the driver, more precisely it analyses the eyes and check if they are closed or open. The number of frames in which eyes are closed is determined. When this number of frames is above a certain threshold, the driver will get a visual warning, on the navigation display, that points out he is drowsy.
Nanobubble Extravasation in Prostate Tumors Imaged with Ultrasound: Role of Active versus Passive Targeting

Microbubble-enhanced ultrasound (US) has shown promise in detection of prostate cancer (PCa), but sensitivity and specificity of detection remains under 65%. Development of a more effective contrast agent for enhanced delineation of PCa with US could provide significant improvement in this area. Targeted nano-sized US contrast agents with improved capability to extravasate and accumulate in tumors may result in prolonged signal enhancement and improved detection of PCa with US. We have developed a long-circulating nanobubble (NB) targeting the prostate-specific membrane antigen (PSMA), a known biomarker expressed on PCa cells. In this study, using a unique US-pathology correlation scheme, we compared rapid tumor accumulation of PSMA-targeted NB (PSMA-NB) in PSMA-positive PC3pip tumor compared to that of untargeted NB and the commercially available microbubble (MB), Lumason®. Significant enhancement was seen especially after 15 min of post admiration of PSMA-NB in the PSMA-positive tumor, with minor washout. In contrast, untargeted NB and Lumason® signal decayed continuously after peak. At 25 min after administration of PSMA-NB showed 4-fold high signal enhancement compared to NB $(4.0\pm 1.5\ \text{vs}\ 1.0\pm 1.1\text{dB},\ \text{p} < 0.001)$ both before and after tumor perfusion. Results indicate that active targeting of NBs to PSMA selectively enhances tumor accumulation and is critical for tumor retention, and both processes can be successfully monitored in real time using contrast-enhanced ultrasound.
Analyzing the Channel Aging Effects on Massive MIMO Downlink by Ray-Tracing

The influence of channel aging effects on massive Multiple-Input Multiple-Output (MIMO) downlink performance for a single-cell urban scenario is investigated by ray-tracing simulations. The scenario comprises 256 base station antennas and 64 single antenna users, which are mobile and travel with a constant speed. Ray-tracing simulations are used to calculate the instantaneous channels in every 100 microseconds for a 10 milliseconds time span. The average downlink data rate in the network is calculated at each time instance. The deterioration of the performance is demonstrated when the channel state information (CSI) available at the base station gradually deviates from the actual channel. The procedure is repeated for different user speeds and different numbers of transmitter antennas. The results are compared to a statistical channel aging model where the aging effect is captured by introducing a correlation coefficient and a random error parameter to a previously known channel matrix.
A 13-ENOB Second-Order Noise-Shaping SAR ADC Realizing Optimized NTF Zeros Using the Error-Feedback Structure

The noise-shaping successive approximation register (NS-SAR) analog-to-digital converter (ADC) is an emerging hybrid architecture that achieves high resolution and power efficiency simultaneously by combining the merits of the SAR ADC and the <inline-formula> <tex-math notation="LaTeX">$\Delta \Sigma $ </tex-math></inline-formula> ADC. Most prior works adopting the cascaded integrator feed-forward (CIFF) structure demonstrate inefficiency in realizing optimized noise transfer function (NTF). This paper presents a second-order NS-SAR ADC employing the error-feedback (EF) structure to realize complex NTF zeros for noise-shaping enhancement with the minimum modification to a standard SAR. It implements a low-power scaling-friendly EF path by using a passive finite impulse response (FIR) and a comparator-reused dynamic amplifier with process-voltage-temperature (PVT) tracking background calibration. Fabricated in 40-nm CMOS, the prototype chip consumes <inline-formula> <tex-math notation="LaTeX">$84~\mu \text{W}$ </tex-math></inline-formula> when operating at 10 MS/s. The NS-SAR achieves peak Schreier FoM of 178 dB with 79-dB signal to noise and distortion ratio (SNDR) at an oversampling ratio (OSR) of 8.
Pulse Power Supply for High-Power Semiconductor Laser Diode Arrays With Micro-Current Pre-Start Control

This paper mainly introduces a pulse power supply for high-power semiconductor laser diode arrays with a novel micro-current pre-start control method. According to the operating characteristics of the semiconductor laser, the output current of the pulse power supply is required to be smooth, stable, and without overshoot. In the method of normal direct pulse start control, semiconductor laser is damaged easily by the overshoot and oscillation of pulse current caused by the switching threshold voltage of MOSFET. And the time delay between the current reference signal and the output pulse current makes the design of closed loop more complicated. Based on the above problems, the method of micro-current pre-start control is proposed. The method is simple to operate and it can solve the nonlinear problem of MOSFET caused by the switching threshold voltage. Therefore, it solve the problems of time delay between the current reference signal and the output pulse current and the overshoot and oscillation of output pulse current in the rising process. A 25.6-kW prototype is intended for verifying the effectiveness of the micro-current pre-start control.