Miracle-dz/UniFAR-FTUs huggingface dataset:
Design of Modified $4\times6$ Filtering Butler Matrix Based on All-Resonator Structures

In this paper, two novel <inline-formula> <tex-math notation="LaTeX">$4 \times 6$ </tex-math></inline-formula> filtering Butler matrices with uniform and nonuniform power distribution are proposed. The matrices, consisting of a network of coupled resonators and two phase shifters, provide power division and phase shift together with a bandpass transfer function. The analytical synthesis procedures for the <inline-formula> <tex-math notation="LaTeX">$4 \times 6$ </tex-math></inline-formula> filtering Butler matrices are presented. To verify the concept experimentally, two <inline-formula> <tex-math notation="LaTeX">$4 \times 6$ </tex-math></inline-formula> filtering Butler matrices, operating at 2.4 GHz, with uniform and nonuniform power distribution are designed, fabricated, and measured. Simulated and measured results are found to be in good agreement with each other. Multibeam antenna arrays are realized by using the Butler matrix, and the theoretical analysis has been confirmed by measurements of multibeam antenna arrays, which show reduced sidelobe level (SLL).
Some Complexity Results for the k-Splittable Flow Minimizing Congestion Problem

In this paper, we mainly consider the complexity of the k-splittable flow minimizing congestion problem. We give some complexity results. For the k-splittable flow problem, the existence of a feasible solution is strongly NP-hard. When the number of the source nodes is an input, for the uniformly exactly k-splittable flow problem, obtaining an approximation algorithm with performance ratio better than (√5+1)/2 is NP-hard. When k is an input, for single commodity k-splittable flow problem, obtaining an algorithm with performance ratio better than is NP-hard. In the last of the paper, we study the relationship of minimizing congestion and minimizing number of rounds in the k-splittable flow problem. The smaller the congestion is, the smaller the number of rounds.
Differentiation of stabilized nitrocellulose during artificial aging: Spectroscopy methods coupled with principal component analysis

In this work, Fourier transform infrared spectroscopy (FTIR) and X‐ray powder diffraction (XRD) were selected as reliable, fast, and nondestructive techniques to assess their potentialities for characterization and discrimination of nitrocellulose (NC)‐based formulations containing different kinds of stabilizers and subjected to accelerated aging. Preliminary results based on visual comparison of the spectra point out that spectra obtained by both spectroscopic techniques were useful for a rapid detection of the aging process without additional sample preparation. Additionally, the existence of compatibility issues between NC and one of the stabilizers is easily recognized. The spectral data were subjected to principal component analysis (PCA) for visualization and to reveal differences between samples. The obtained results demonstrated that PCA plots were able to distinguish and classify the NC samples with respect to their respective stabilizers and aging.
Block-matrix-based approach for the vehicle routing problem with transportation type selection under an uncertain environment

ABSTRACT The vehicle routing problem has become a fundamental part of supply chains in competitive environments. Many studies have been conducted on the uncertain vehicle routing problem to improve transportation plans. However, few have concentrated on the selection of transportation type under uncertain environments. In this study, a novel vehicle routing model that considers transportation type selection between milk-run and cross-dock strategies under uncertain environments with fuzzy travel time is proposed. Furthermore, a novel block-matrix-based approach for the transportation type selection is presented to explore optimal transportation plans in an intuitive, reasonable, effective and efficient form. An extended biogeography-based optimization algorithm is proposed to derive an optimal transportation plan by extending the migration and mutation operators, and introducing a novel self-adaptive mutation rate and a secondary mutation operator. Finally, simulation experiments are performed to validate the effectiveness and practicality of this approach in solving the proposed model.
Decreased sensitivity to changing durational parameters of syllable sequences in people who stutter

ABSTRACT Stuttering is a disorder that affects the coordination of complex sequencing mechanisms that define the temporal layout of speech. However, classical motor areas of the brain, responsible for the sequencing of articulatory aspects in speech production also process non-verbal and even non-motor temporal information. This configuration suggests that perceptual temporal processing capacities may factor into the symptom profile of various motor disorders. We investigated perceptual sensitivity for changing temporal parameters of sequentially presented consonant–vowel-consonant syllables in people who stutter (PWS) and matched controls. Changes were durational contrasts (short vs. long) of the whole syllable and/or the vocalic nucleus. Analyses focused on sensitivity indices (d’), response times, response time variability, and co-variation of these variables with offline measures of cognitive performance. Results indicate lower sensitivity for durational contrasts and longer and more variable response times for long vowels in the PWS group, pointing towards subtle perceptual verbal temporal processing differences.
A Real-Coded Optimal Sensor Deployment Scheme for Wireless Sensor Networks Based on the Social Spider Optimization Algorithm

Wireless sensor networks (WSNs) involves a set of wireless sensor nodes located within a region of interest (ROI) to acquire and/or transmit specific information from their surroundings. A common problem in the operation ofWSNs is sensor coverage, which is related to the distribution of sensor nodes within their ROI. Several approaches have been proposed to solve this problem; however, most of these methods consider a simplified arrangement scheme based on sensor placement over a set of fixed discrete locations defined by a grid. This fact severally limits the ability of these methods to find potentially better solutions as they are conditioned to select a limited number of candidate solutions. In this paper, a real-coded sensor deployment approach based on the Social Spider Optimization (SSO) algorithm is proposed to solve the problem of optimal sensor deployment (OSD) in WSNs. The performance of our proposed approach (referred in this paper as real-coded SSO [R-SSO]) was also compared against other metaheuristics-basedmethods used in the literature. Experimental results demonstrate its ability to solve the problem of OSD in terms of accuracy and robustness. © 2019 The Authors. Published by Atlantis Press SARL. This is an open access article distributed under the CC BY-NC 4.0 license (http://creativecommons.org/licenses/by-nc/4.0/).
Research on Remaining Useful Life Prediction of Rolling Element Bearings Based on Time-Varying Kalman Filter

Rolling bearings are the key components of rotating machinery. Thus, the prediction of remaining useful life (RUL) is vital in condition-based maintenance (CBM). This paper proposes a new method for RUL prediction of bearings based on time-varying Kalman filter, which can automatically match different degradation stages of bearings and effectively realize the prediction of RUL. The evolution of monitoring data in normal and slow degradation stages is a linear trend, and the evolution in accelerated degradation stage is nonlinear. Therefore, Kalman filter models based on linear and quadratic functions are established. Meanwhile, a sliding window relative error is constructed to adaptively judge the bearing degradation stages. It can automatically switch filter models to process monitoring data at different stages. Then, the RUL can be predicted effectively. Two groups of bearing run-to-failure data sets are utilized to demonstrate the feasibility and validity of the proposed method.
A channel estimation scheme for MIMO-OFDM systems

In view of the contradiction of the time-domain least squares (LS) channel estimation performance and the practical realization complexity, a reduced complexity channel estimation method for multiple input multiple output-orthogonal frequency division multiplexing (MIMO-OFDM) based on pilot is obtained. This approach can transform the complexity of MIMO-OFDM channel estimation problem into a simple single input single output-orthogonal frequency division multiplexing (SISO-OFDM) channel estimation problem and therefore there is no need for large matrix pseudo-inverse, which greatly reduces the complexity of algorithms. Simulation results show that the bit error rate (BER) performance of the obtained method with time orthogonal training sequences and linear minimum mean square error (LMMSE) criteria is better than that of time-domain LS estimator and nearly optimal performance.
Influence of mesh geometries on the design of transparent antennas at 2.45 GHz

This paper presents optically transparent dipole antennas with innovative meshes for printing processes. The influence on antenna performance of the meshing geometry, the width and the pitch of dipole are investigated. The study shows that, for a given width, an increase of the performance with a twin small pitch with circle geometry. Furthermore, the antennas with an optical transparency of 70% present a loss of the realized gain around 0.35% compared to an opaque conventional dipole antenna with the same width.
Rancang Bangun Pemanas Induksi dengan Metode Multiturn Helical Coil

Pemanas induksi merupakan sumber renewable energy di bidang pemanasan baik itu logam ataupun yang lainnya. Keunggulan dari pemanasan induksi ini adalah lebih ramah lingkungan karena tidak memiliki gas buang dan sisa sampah pembakaran. Dalam penelitian ini penulis membuat sebuah pemanas induksi dengan menggunakan metode multiturn helical coil. Metode multiturn helical coil merupakan sebuah metode yang membuat kumparan kerja dibuat secara melingkar ke arah vertikal. Metode ini banyak digunakan untuk memanaskan sebuah logam. Dalam pengujian ini volume dari material yang diuji sama yaitu sekitar 35,4 cm3. Setelah dilakukannya pengujian, didapat hasil konsumsi daya untuk memanaskan sebuah benda hingga suhu 100 °C adalah 120 watt dengan daya dari catu daya 10 A, 12 VDC. Konsumsi daya tersebut lebih rendah jika dibandingkan dengan produk sejenis yaitu kompor induksi yang ada di pasaran dengan suhu untuk memasak sekitar 100 °C memiliki konsumsi daya 300 watt hingga 1000 watt.
The Effect of Turbulence on the Accretional Growth of Graupel

Wind tunnel experiments were carried out to investigate the influence of turbulence on the collection kernel of graupel. The collection kernel defines the growth rate of a graupel accreting supercooled droplets as it falls through a cloud. The ambient conditions were similar to those occurring typically in the mixed-phase zone of convective clouds, that is, at temperatures between −7° and −16°C and with liquid water contents from 0.5 to 1.3 g m−3. Tethered spherical collectors with radii between 220 and 340 μm were exposed in a flow carrying supercooled droplets with a mean volume radius of 10 μm. The vertical root-mean-square fluctuation velocity, the dissipation rate, and the Taylor-microscale Reynolds number of the turbulent flow were determined as urms = 0.13 m s−1, ε = 0.13 m2 s−3, and Rλ = 48, respectively. The collection kernels of tethered graupel grown under laminar and turbulent conditions revealed no measurable difference, indicating that turbulence has no effect on the growth of graupel in the investigated size range. A comparison of laminar collection kernels to theoretically calculated values from a continuous growth model showed that graupel growth is strongly dominated by the fast increase of the radius due to the accretion of rime ice with low density. It is assumed that, compared to a water drop growing by collision and coalescence, this causes a fast increase in the swept volume overcompensating all other effects such as the self-induced stochastic movements due to surface roughness and latent heat release, as well as the possible influence of the flow’s small-scale turbulence.
Avaliação da percepção da qualidade dos serviços de postos de saúde no interior de Pernambuco

The perception of quality in services gains relevant space in studies in the area, so this research has the objective of evaluating the perception of the quality of the services of health posts in the districts of Umari and Sítio Aroeiras located in the city of Bom Jardim, in the interior of Pernambuco. The model chosen to evaluate this perception was the hierarchical and multidimensional model proposed by Brady & Cronin (2001). As a tool for collecting the research, the questionnaire was used, which was based on the authors' study. The authors' model is composed of 3 dimensions (quality of interaction, quality of environment and quality of result) and 9 sub-dimensions (attitude, behavior, expertise, environmental conditions, design, social factors, waiting time, tangibles and valence). Structural Equation Modeling (SEM) was used to analyze the data. The results show that for the sample consulted, only the quality dimension of the environment is relevant to evaluate the overall quality, the other dimensions are not significant. Among the sub-dimensions, the only one that was relevant for environmental quality was environmental conditions. These results demonstrate that the users of the service attach importance to the physical facilities and to a good environment, that is, the place of care being warm, comfortable and clean are expressive factors for the perception of the consumer.
Simple saturated relay non‐linear PD control for uncertain motion systems with friction and actuator constraint

This study addresses the problem of robust fast and high-precision positioning of uncertain one-degree-of-freedom mechanical systems with friction and actuator constraint. The proposed control is constructed within the framework of saturated proportional–derivative (PD) plus relay action. Global asymptotic positioning stability is proven by Lyapunov's direct method with Barbalat's lemma. The appealing features of the proposed control are that it is fairly easy to construct with simple intuitive structure and the absence of modelling parameter in the control law formulation, and thus it is ready to implement for practical applications. An additive feature is that the proposed control embeds the PD action within one saturation function and hence it omits the elaborating embedment of the control gains within the requested constraint. Another feature is that the proposed approach can be explicitly upper bounded a priori and thus, it has the ability to protect the actuator from saturation completely and to ensure global asymptotic stability featuring fast transient and high steady-state positioning. Numerical simulations and real experimental results demonstrate the effectiveness and improved performance of the proposed approach.
Extinction coefficients of surface atmospheric aerosol above LHAASO

We investigate the extinction coefficients of the surface atmospheric aerosol over the Large High Altitude Air Shower Observatory (LHAASO), located at the Haizi Mountain, Daocheng County, China. To this end, we utilize the Longtin model, Mie scattering theory, and experimental data obtained by the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO). Our theoretical calculations show that the total extinction coefficients of the atmospheric aerosol at the wavelength of 200–500 nm are inversely proportional to the laser wavelength, and influenced by the wind speed. From July 2015 to October 2016, the extinction coefficient of the surface atmospheric aerosols at 532 nm wavelength reached 0.04 km with no wind, while it increased to 0.1 km with gusts. In this period, the extinction coefficients of the surface atmospheric aerosol at 532 nm wavelength, obtained by the CALIPSO, change from 0.01 to 0.07 km, which is less than the values obtained the theoretical calculation and larger than the average of Tibetan Plateau in 2006−2016. These calculations and experimental evidence provide important arguments to the model of atmospheric aerosol to be applied in the calibration of LHAASO. Our results suggest that the extinction coefficients over LHAASO require further study, including research on the size distribution, shape, concentration of aerosols particles, wind dependence, relative humidity dependence, etc.
Reconfigurable Phased-Array Antenna Using Continuously Tunable Substrate Integrated Waveguide Phase Shifter

A low-cost $1 \times 4$ phased array incorporating continuously tunable substrate integrated waveguide (SIW) phase shifters is presented in this paper. Through seamless integration between antenna elements, phase shifters, and an SIW feeding network, the proposed phased array is assembled in a multilayered monolithic structure. To obtain a wide phase variation range, the electronically controllable phase shifter is constructed by introducing varactor diodes into a reflection-type architecture, which can also offer a simple solution to constitute the biasing circuit of the diodes. Due to the merits of adequate bandwidth and good radiation performance, an aperture-coupled patch antenna with multi-resonance characteristic is selected as the array element. Accordingly, a prototype of the proposed phased array was fabricated by applying standard printed circuit board (PCB) facilities. The measured results demonstrate that a continuous beam scanning range from −45° to 45° covering the whole operating band of 5.09–5.98 GHz is obtained. Meanwhile, a gain of up to 11 dBi and an impedance bandwidth of 16.1% are achieved. Owing to the features of continuous wide-angle steerable beam, easy fabrication, and integration, the proposed phased-array antenna is attractive for 5G Wi-Fi applications.
An Efficient Authenticated Key Transfer Scheme in Client-Server Networks

In this paper, we presented a novel authenticated key transfer scheme in client-server networks, which can achieve two secure goals of remote user authentication and the session key establishment between the remote user and the server. Especially, the proposed scheme can subtly provide two fully different authentications: identity-base authentication and anonymous authentication, while the remote user only holds a private key. Furthermore, our scheme only needs to transmit 1-round messages from the remote user to the server, thus it is very efficient in communication complexity. In addition, the most time-consuming computation in our scheme is elliptic curve scalar point multiplication, so it is also feasible even for mobile devices.
Partial Discharge Angle of Arrival Estimation Using UHF Wireless Sensor Array

The detection and localization of partial discharge (PD) in air-insulated substations by ultra-high frequency (UHF) technology is widely studied. Existing UHF PD localization system mainly focus on time-difference of UHF signal, which requires very high synchronized sampling rate. This paper proposes a received signal strength (RSS) based angle of arrival (AoA) method by a circle UHF wireless sensor array. An AoA estimation scheme is derived through the radiation pattern of designed UHF antenna. Interpolation and neural network are applied to improve the AOA resolution. A field test is performed to verify the effectiveness of the proposed PD localization system. The results show that the estimated error on average is below 7°. Compared to the time-difference-based method, the accuracy of our designed system is more feasible for practical application considering its significant low-cost feature.
Review of modern vehicle modelling

Earlier models were a simplified form of the complex vehicle system, which was governed by the important parameters and states. These parameters and states were either obtained indirectly through some simplified equations or directly measured using instrumentation. In either case, the models were designed on the basis of parameters and state availability or importance, and not to have a complete model representation and maximum parameter utilization through estimation and instrumentation. Since a complete vehicle model can lead to a better controller. Without considering all the important parameters, a complete model is not obtained to design better controllers. All types of controllers, classical, optimal, nonlinear and linear controllers use the basic equations that govern the vehicle dynamics. This paper reviews all the previous models with greater insight into each system. The aim is to provide a better understanding of each model, its shortcomings and how it can represent the complex vehicle model.
Microstrip Coupled Band Pass Filter using Parallel Coupled Lines used for EMI Reduction

The use of BPF is in telecommunications wireless systems. The signal to be transmitted and which they are received are filtered at a center frequency having some significant bandwidth. This paper comprises a brief knowledge related to designing of a band pass filter (BPF) using microstrip parallel coupled line structure for reduction of noise and EMI. The band pass filter has a center frequency of 2.45GHz having less insertion loss and more than 20dB return loss in its pass band having more than 5% moderate bandwidth is successfully designed.The center frequency is selected such that it is mainly used in WLAN network or high speed wireless broadband is configured to transmit data voice and video IP because system requires more bandwidth. The layout is designed such that centre frequency is 2.45GHz with a fractional bandwidth of 200MHz and impedance resonator length of each coupled line is seperated such that impedance is adjusted to 50Ω exactly.Two sections are mainly given in design: two coupled lines distinguished by a non-uniform line resonator.The impedance resonators gives a separate resonance to obtain the passband region or response.The simulation is perform out on a HFSS software.
ARCHETYPAL ANALYSIS: AN ALTERNATIVE TO CLUSTERING FOR UNSUPERVISED TEXTURE SEGMENTATION

Texture segmentation is one of the main tasks in image applications, specifically in remote sensing, where the objective is to segment high-resolution images of natural landscapes into different cover types. Often the focus is on the selection of discriminant textural features, and although these are really fundamental, there is another part of the process that is also influential, partitioning different homogeneous textures into groups. A methodology based on archetype analysis (AA) of the local textural measurements is proposed. AA seeks the purest textures in the image and it can find the borders between pure textures, as those regions composed of mixtures of several archetypes. The proposed procedure has been tested on a remote sensing image application with local granulometries, providing promising results.