Miracle-dz/UniFAR-FTUs huggingface dataset:
A Novel Solid-State Circuit Breaker for DC Microgrid System

The development of the DC microgrid system has promoted the development of the DC circuit breaker. However, the traditional DC circuit breaker exists many problems such as long period of fault interruption, complex circuit structure, existing arc, low reliability and low anti-interference. Aiming to solve these problems, an improved solid-state DC circuit breaker was proposed in this paper. This improved solid-state circuit breaker uses a transformer instead of LC legs which exist in the traditional Z-source circuit breakers to realize the function of turning off the thyristor. The working principle and designing process are discussed in this paper according to the results of simulation based on Saber. And the operation performance of the improved solid-state circuit breaker is validated by the calculation and simulation results.
Study of salivary arecoline in areca nut chewers

Aims: Arecoline, a predominant alkaloid present in arecanut, has been implicated in the pathogenesis of several oral diseases because of its mutagenic and carcinogenic potential. The response of cultured cells to arecoline is highly dependent on its concentration; arecoline stimulates cultured cells above 0.1 μg/ml and is cytotoxic above 10 μg/ ml. Although this alkaloid seems important for areca nut induced oral diseases and carcinogenesis, little is known of the levels achieved before, during and after chewing. Also, it is prudent to understand its effects in arecanut chewers for a comprehensive understanding of its pathogenesis. Accordingly, the present study quantified the salivary arecoline levels in arecanut chewers. Materials and Methods: The study participants were divided into Study Group A & B and Control Group C; unstimulated whole saliva was collected by spitting method for a period of 5 min. Then, participants in Group A and C chewed 0.5 g of areca nut without any other additives while in Group B were asked to chew 0.5 g of inert rubber base impression material. Stimulated whole saliva from all three groups was collected into graduated tubes during chewing at time intervals of 1, 3, 5, 10, 15, 20 and 25 min. Then, all participants were asked to remove nut particles or inert rubber base material from the mouth, and saliva samples were collected further up to 20 min, changing tubes at 5 min interval. Salivary arecoline was quantitated by HPLC-MS. The tabulation and descriptive statistics of the study were carried out. Results: In the present study, baseline levels of arecoline were zero in all three groups, whereas mean salivary arecoline levels during chewing were 76.93 ng/ml, 129.83 ng/ml and 64.83 ng/ml and after chewing were 196.17 ng/ml, 321.12 ng/ml and 43.75 ng/ml in Groups A, B and Control respectively, which were significantly higher than reported threshold levels. Conclusions: The data from this study reveals that a significant amount of arecoline would be trapped in oral cavity, or being re-circulated between blood and saliva might have resulted in surprisingly high levels of arecoline even 10 mins after chewing in both groups after which the levels started declining. The higher levels of salivary arecoline achieved during and after chewing are enough to cause cytotoxic and genotoxic effects on oral tissues over a period of time in chronic chewers. The great differences in salivary arecoline levels achieved during chewing, may contribute to the variable response to areca nut seen in communities where this habit is widespread. Areca nut users have persistent background salivary arecoline levels long after chewing, whereas concentrations achieved are highly variable and consistent with a role in oral pre-malignancy and malignancy.
Sizing Procedure of PMSMs for Hybrid Parallel Aircraft Propulsion

The aim of the paper is to present an optimized procedure for the preliminary sizing of permanent magnet motors used for the hybrid parallel propulsion of passengers aircrafts. The procedure is finalized to obtain high values of the motor power density and is carried out by means of a non-gradient approach with evolutionary algorithm integrated with magnetic and thermal finite element analyses. The target of the procedure is the achievement of a preliminary sizing of the motor suitable for the aircraft propulsion, starting from motors usually employed in other traction applications. Some numerical results are discussed in the paper with reference to significant case studies.
Guidelines for DNA recombination and repair studies: Cellular assays of DNA repair pathways

Understanding the plasticity of genomes has been greatly aided by assays for recombination, repair and mutagenesis. These assays have been developed in microbial systems that provide the advantages of genetic and molecular reporters that can readily be manipulated. Cellular assays comprise genetic, molecular, and cytological reporters. The assays are powerful tools but each comes with its particular advantages and limitations. Here the most commonly used assays are reviewed, discussed, and presented as the guidelines for future studies.
An Application for Skin Macules Characterization Based on a 3-Stage Image-Processing Algorithm for Patients with Diabetes

Diabetic skin manifestations, previous to ulcers and wounds, are not highly accounted as part of diagnosis even when they represent the first symptom of vascular damage and are present in up to 70% of patients with diabetes mellitus type II. Here, an application for skin macules characterization based on a three-stage segmentation and characterization algorithm used to classify vascular, petechiae, trophic changes, and trauma macules from digital photographs of the lower limbs is presented. First, in order to find the skin region, a logical multiplication is performed on two skin masks obtained from color space transformations; dynamic thresholds are stabilised to self-adjust to a variety of skin tones. Then, in order to locate the lesion region, illumination enhancement is performed using a chromatic model color space, followed by a principal component analysis gray-scale transformation. Finally, characteristics of each type of macule are considered and classified; morphologic properties (area, axes, perimeter, and solidity), intensity properties, and a set of shade indices (red, green, blue, and brown) are proposed as a measure to obviate skin color differences among subjects. The values calculated show differences between macules with a statistical significance, which agree with the physician's diagnosis. Later, macule properties are fed to an artificial neural network classifier, which proved a 97.5% accuracy, to differentiate between them. Characterization is useful in order to track macule changes and development along time, provides meaningful information to provide early treatments, and offers support in the prevention of amputations due to diabetic feet. A graphical user interface was designed to show the properties of the macules; this application could be the background of a future Diagnosis Assistance Tool for educational (i.e., untrained physicians) and preventive assistance technology purposes.
Psychometric Properties of the Dental Activities Test: An Exploratory Factor Analysis in Older Adults with Cognitive Impairment

Objective The Dental Activities Test (DAT) was developed to be used by dental, nursing, and other health professionals to assess the ability of persons with dementia to perform oral health-related activities and aid care planning. The instrument was designed as a unitary scale and has excellent internal consistency, test-retest reliability, interrater reliability, and construct validity. This study examines the underlying factor structure of the DAT among older adults in assisted living settings. Methods In a secondary analysis of the data from the original study, the results of testing of 90 older adults with normal to severely impaired cognition from three assisted living communities in North Carolina from March 2013 to February 2014 were studied. An exploratory factor analysis was used to assess the dimensionality of the presumed unitary assessment scale. Results Two-factor structures were explored. A one-factor model demonstrated acceptably mixed model fit, and a two-factor model had good model fit with moderate correlation between the two factors (r = 0.667, p < 0.05). All the items in the one-factor model demonstrated significant factor loadings (loadings ≥ 0.39, all p < 0.05), while the loadings of some items in the two-factor model (nonsignificant or cross-loadings, loadings < 0.40) did not meet the criteria of factor selection. The one-factor structure was preferred based on the criteria of Scree Plot, eigenvalue, and factor interpretability in relation to clinical relevance. Conclusions The study provided preliminary evidence that the Dental Activities Test has a unidimensional construct among older adults with cognitive impairment. It suggested that this instrument can be used as a unitary scale to assess dental-related function in persons with dementia. Future testing, including using a confirmatory factor analysis, in a new sample is needed to further assess the usefulness and psychometric properties of this instrument.
A Ultra-Light High Gain Circularly-Polarized Antenna Array for Mobile Satellite Terminals

A ultra-light, compact, high gain 16 × 6 CP antenna array is presented in this paper for Ku band mobile satellite applications. The 96-element array consists of 24 2 × 2 CP sub arrays fed by a substrate-integrated-waveguide (SIW) network. Two essential and innovative techniques were adopted in this design. First, in order to achieve the ultra-light weight, the radiation patches were etched on the Polyimide film supported by a patterned foam. A piece of thin SIW network was designed to feed the radiators. The total weight of the fabricated array prototype is only 66.5 gram and profile is low as 0.05 λ0. Second, a sequential rotation (SQR) feeding technique was applied to the aperture fed 2 × 2 CP sub array, which realized more than three times bandwidth enhancement than the direct (non-SQR) feeding approach. In addition, the measured results show the CP-operational bandwidth is 700 MHz from 11.55 to 12.25 GHz. The peak realized gain is 26.4 dBic and gain variation is stable (less than 3 dB) cross the entire operating bandwidth. Be ultra-light and high gain, it is an excellent candidate for Ku band satellite applications.
Imaging of Two Dimensional Scatterers using Descent Learning Technique

In this work, we study the application of the supervised descent method to two-dimensional electromagnetic inverse problems. The inversion process contains two stages: offline training and online prediction. In the offline stage, the average descent directions of cost functions are learned from a set of training data; and in the online stage, model reconstruction is achieved through iterative minimization based on learned descent directions. This scheme offers a new perspective to incorporate prior information into inversion, and reduce the computational complexity in the online inversion. Numerical examples validate the accuracy and efficiency of this method.
Development of a Textile Antenna Using a Continuous Substrate Integrating the Ground Plane

The exponential growth in the wearable market is boosting the industrialization process of manufacturing textile antennas. The patch of the printed antennas can be easily cut, embroidered or screen printed by machines. The conception of an optimal industrial substrate that meets all the mechanical and electromagnetic requirements is still a challenge. This paper presents a printed textile antenna for ISM band using a continuous Substrate Integrating the Ground Plane (SIGP). The SIGP is a novel textile material, which is a double fabric that integrates the dielectric substrate and the conductive ground plane in a single textile.
Study of Bend to Twist Coupling of Composite Laminates for Passive Load Alleviation of a Wind Turbine Blade

One of the biggest challenges wind turbines in low speed wind regions (sudden extreme wind speeds) face, is bearing the sudden and excessive loads caused by typhoons and tropical cyclones in the region. The extreme turbulence and rapid change in the wind direction and speeds are the major causes of wind turbine failures. This leads to blade pitch angle error in the traditional pitching mechanism used for load alleviation, causing large responses in terms of rotor thrust and generator torque. This can potentially lead to fatal accidents. Hence, passive load alleviation techniques are gaining ground, bend to twist coupling of anisotropic composite laminates in particular. The induced twist when the laminate is under bending loads helps reduce excessive loads in the structure. This concept can be applied to the blades of the stalled wind turbines to withstand extreme loads. Previous research findings support this hypothesis and show that eliminating the pitching subsystems can help create lighter blades that require less maintenance. In this study, five single-ply and five two-ply laminates are analysed using a MATLAB program to determine their bending-twisting coupling coefficients, strains and stresses under an applied moment. For our loading condition, the study seems to indicate that the addition of the 25° ply is optimal in terms of reducing the stresses by twisting. Further work is required in order to understand the effect of the number of plies, ply architecture, different cross-sections, etc. on the bend-twist coupling of composite structures so as to incorporate it into a wind turbine blade spar.
Variants of the Block-GMRES Method for Solving Linear Systems with Multiple Right-Hand Sides

The solution of large linear systems with multiple right-hand sides given simultaneously is required in many large-scale scientific and engineering applications modelled by either partial differential or boundary integral equations. In this paper we introduce variants of the block GMRES method that combine initial deflation and eigenvalue recycling strategies to remedy some typical convergence problems of block Krylov solvers.
Radiation Pattern Characterization of Terahertz Photoconductive Antennas Using Time-Domain Spectroscopy System

This paper presents the radiation pattern characterization of terahertz photoconductive antennas using a new technique. The proposed technique is implemented using a modified terahertz time domain spectroscopy by applying a full mapping of the THz beam. The proposed method was also compared with analytical methods and numerical solvers. The comparison of the measured results with that of the simulations shows a half-power beam width error of 1.5°and an optical path difference error of 8%. To the best of our knowledge, this is the first time terahertz time domain spectroscopy system is used to characterize the radiation pattern of terahertz photoconductive antennas.
Characterizing Mobility and Service Pattern of Mobile Users Based on Wireless Data Analysis

Massive amount of data and information are produced by the wide-spread usage of mobile devices like smartphones. Data analysis of large amounts of wireless network data is crucial in understanding user behaviors and service usage patterns. Understanding and forecasting mobile user behaviors is not only valuable for service providers to control and manage mobile network, but also improve the user experience. In this paper, we first introduce the cellular network architecture and describe the features of wireless data collected from mobile network. Then we present a complete analysis process on the wireless data. After preprocessing, we perform an analysis on data traffic from different aspects to understand user behavior patterns. We also discuss several significant ways of utilizing the results of analysis in this study to solve some current problems.
The Sequential Importance Sampling Particle Filter with a Systematic Resampling in the State Estimation of Power Systems

Power System State Estimation (PSSE) is a substantial matter in the management of electrical power systems (EPS). This article provides a referential study for the understanding of the Sequential Importance Sampling (SIS) Particle Filter (PF) with a Systematic Resampling (SysR) in PSSE. Two performance indexes are used to assess the performance of the SIS PF with SysR: an index of error ($\epsilon $) and the J Performance Index. Also, the implementation of the method was tested in two standard power systems, the IEEE 14-bus and 30-bus test cases, under two scenarios which are the normal operation and sudden load change. The algorithms that support the implementation of the method were tested in MATLAB. From test results, they help support the feasibility of the method for state estimation applications.
Dual-band Antenna Decoupling Design with Stepped Impedance Loaded Dual-band Dummy Element

This paper presents a compact dual-band WLAN MIMO antenna with improved isolation. The antenna covers 2.45GHz and 5.8GHz band, and high isolation at 2.45GHz and 5.8GHz between the antennas is obtained by using one dummy element with a second-order impedance transmission line. The measured results proved that proposed antenna has good impedance matching performance and high isolation.
A Hybrid Integral Equation Approach to Solve the Anisotropic Forward Problem in Electroencephalography

The boundary element method provides a computationally efficient solution to the Electroencephalography (EEG) forward problem on piece-wise homogeneous head models by using surface integral equations. However, realistic modeling of the head medium requires a proper account of the anisotropic electric nature of the human skull, which cannot be handled by standard surface integral equations. This work addresses this issue by presenting a new formulation which perturbs the standard Lippmann-Schwinger approach with volume elements within the skull. The resulting surface/volume integral equation can handle computations of fully realistic modeling for both skull and white matter. Numerical results will confirm the validity of the approach as well as its applicability to real case scenarios.
E-Gardener: Building a Plant Caretaker Robot Using Computer Vision

Advancement in trends provokes new ideas in our mind. We often desire intelligent robots that can solve our daily routine tasks. This paper successfully outlines the ways and methodologies that can be used to develop a robot that can monitor the growth of plants in the absence of human beings. As humans need proper food and nutrients to keep us energetic and working, similarly plants require proper nutrients in order live longer. The proposed method consists of a mobile robot integrated with a novel algorithm (implementing the concepts of Computer Vision) to segment out the plants from the image in the best possible way. This algorithm is much more robust to lightning conditions as compared to other available algorithms. The application of this research might not only improve the conditions of plants and trees but can also result in the overall improvement of our surroundings and atmosphere.
Graphene-based four-port THz circulator*

We propose an approach for the design of graphene-based four-port circulator for THz region. The device presents a three-layer structure consisting of layers of graphene, silica (SiO2) and silicon (Si). The in-plane figure of the circulator consists of a circular graphene resonator and two waveguides laterally coupled to it. The device is magnetized by an external DC magnetic field normal to the plane of the resonator. The working principle of the device is based on the dipole resonance of the magnetized graphene resonator. Numerical calculations demonstrate the isolation greater than −15 dB and the insertion loss better then −3.5 dB within the bandwidth of about 4.65 % and the central frequency 5.17 THz for DC magnetic field of 0.8 T and Fermi energy ϵF = 0.15 eV.
Popular platforms for big data analytics: A survey

This paper aims to make a comparative study of the different platforms used in the field of Big data analytics. It lists the different hardware platforms available, and widely used in Big data, to perform data analysis. A detailed description of the frameworks and processing paradigms used by each platform is also provided. Comparison criteria such as scalability, I/O rate, fault tolerance, data size, iterative processing and real-time processing are used to assess the advantages and drawbacks of each of these platforms. A summary table will present the strengths and weaknesses of each platform, then a qualitative and rigorous comparison is discussed according to the criteria mentioned above. Also this document presents the new trends aiming at the improvement of the performances of these platforms by the use of hardware accelerators and also by the convergence of big data analytics frameworks with modern High Performance Computing (HPC) systems. The results of this survey on widely used platforms in big data analytics can help users make an informed decision about choosing the right platform for their data analytics needs.
Tunable Piezo-Actuated Metasurfaces for Millimeter-wave and THz Antennas

We present a new class of low loss dynamically reconfigurable metasurfaces and their applications in the design of a beam steered high gain antenna at millimeter-wave (mm-wave)frequencies. A new tuning technology is applied to multilayer metasurfaces and the advantages of the proposed technology in terms of low loss, high switching speed and overall antenna performance is demonstrated. The proposed technology is scalable to higher mm-wave and THz frequencies using innovative micromachining processes.
Design and Application of Optical Fiber Sensors for Force Myography

The force myography (FMG) is a method for retrieving the hand movements by assessing the radial forces exerted by the forearm muscles. In this context, optical fiber transducers based on different principles (microbending, LPFG, specklegram, and hetero-core structure) are evaluated for the measurement of FMG signals. Furthermore, the microbending transducer was applied on gesture recognition for the real-time control of a virtual prosthetic hand. The sensor presented ~0.05 N−1 sensitivity for a 20 N range and was successfully implemented on the classification of 4 postures, providing a low-cost and reliable approach for controlling multi-grasp bionic hands.
Prevalence of physical inactivity among adolescents in Brazil: systematic review of observational studies

This study aims to analyze the available evidence on the prevalence of physical inactivity among Brazilian adolescents by means of a systematic review of observational studies. They were used 3 databases and 3 virtual libraries with key descriptors of this subject. After applying the eligibility criteria 22 item were identified. The results of the studies showed that over 50% of adolescents are inactive, identifying a higher prevalence in female adolescents. Furthermore, several factors may interfere in this practice (age, sex, socioeconomic status and sedentary behavior). The physical activity acts as a protective agent for health, becoming important at the adolescence, thus promote public and private policies will serve to enhance the physical activity in this population encouraging healthy habits into adulthood.
A Simple Tri-Band Proximity Coupling Fed Compact Antenna for 2.7GHz, WLAN and Sub-6GHz Communication Applications

A simple multi-band antenna is proposed for 2700MHz, upper WLAN and sub-6GHz fifth generation wireless communication applications. The proposed antenna is fed by using a proximity coupling fed structure to excite two spiral strips. The feeding line is a 50-Ohm microstrip line, and the two spiral strips are set at both sides of the feeding line. There is a partial ground plane at the bottom of the FR4 substrate. The designed antenna is created by using the HFSS, and the simulated results from the HFSS show that the antenna has a good triple-band characteristic and an omnidirectional radiation pattern at these three operating bands.