Miracle-dz/UniFAR-FTUs huggingface dataset:
Analysis of Single Section Impedance Transformer using Multiple Cavity Modeling Technique

A Method of moment based analysis of a two section waveguide impedance transformer has been presented using multiple cavity modeling technique (MCMT). Every discontinuity is modeled with a cavity. Several cavities are formed to describe the whole structure. The analyzed waveguide structure has good agreement with the multi cavity modeling technique (MCMT), CST microwave studio simulated and literature data. from the perspective of generalized network formulation. Navarro et al. (12) derived a finite difference time domain numerical dispersion relation for evanescent waves. They made the correction to the numerical evanescent constant to compute the discontinuity parameters. Lin et al. (13) proposed a unified mode matching technique for the calculation of modal scattering matrix of a concentric waveguide junction. The TE and TM modal fields in both waveguides which are connected to form the junction are expressed in the Cartesian coordinate system, so that the coupling coefficients for all the modes can be evaluated effectively. Das and Chakaborty (14) analyzed waveguide based circuits and radiators using multiple cavity modeling techniques (MCMT). A numerical analysis method based on the weak form of the Helmholtz equations was introduced by Wang, Dou and Li (15) to analyze waveguide discontinuity problems like dielectric loaded waveguides, waveguide T-junctions and power dividers. A rigorous analysis of Uniaxial discontinuities microwave components are described by Boyenga, Mabika and Moko (16) using a new multimodal variational technique.
Methods and algorithms for the slicing process in microstereolithography

In this paper, methods and algorithms are presented for an efficient slicing process specifically designed for microstereolithography, a high‐resolution rapid prototyping technology. Modifications are given for different implementation environments (FPU, Parallel Computing, directly wired processes). They use the common STL‐format as the description of the 3D objects and compute bitmapped layers for the layered manufacturing step. Specific attention was paid to the requirements for flexibility, accuracy, supporting standards and performance. A layer‐resolution of up to 32767×32767 pixels is supported. The described system is a flexible solution easy to be coupled with almost any system controller for a micro‐stereolithography machine using the integral irradiation process.
Tunable dispersion slope compensator using a chirped fiber Bragg grating tuned by a fan-shaped thin metallic heat channel

An electrically tunable dispersion slope compensator using a chirped fiber Bragg grating tuned by quadratic temperature distribution is demonstrated. A fan-shaped thin metallic heat channel was used to generate a quadratic temperature gradient along the grating. By controlling the temperature of inner and outer boundaries of the heat channel, we achieved a dispersion slope from -60.82-65.89 ps/nm/sup 2/ for 1.2-nm bandwidth. The dispersion slope compensation in 160-Gb/s return-to-zero transmission is demonstrated by simulation.
Automatic Dual Axis Sun Tracking System using LDR Sensor

The aim of this paper is to present a solar energy collection technology by a photovoltaic cell. To present this efficient solar distributed generation system, a dual-axis solar tracker is designed. The tracker actively tracks the sun and changes its position accordingly to maximize the power output. The designed tracking system consists of sensors, microcontroller operated control circuits to drive DC motors and gear- bearing arrangements with supports and mountings. Two geared dc motors are used to move the solar panel so that sun’s beam is able to remain aligned with the solar panel.
Comparison of Three Display Methodologies for Battlefield Resource Management

As the Army prepares to move into the next century, it is exploring advances in technology that will enable U.S. military forces to obtain more complete data regarding its mission, enemy and friendly troop locations, weather, and target status. Not only will this data be more accurate, it will be collected and transmitted in near real-time. Advanced displays must be developed that allow commanders to efficiently deal with large volumes of data so that effective decisions can be made in a timely manner. This paper describes an experiment comparing three methods of displaying battlefield resources and unit mobility: (1) a combination of alphanumerics and standard Army decision graphics, (2) a configural display (CD) representation, and (3) an associative configural display representation (ACD). Results indicate that performance benefits are realized from both the CD and ACD representations, but the CD proved to be the best overall.
Comparative analysis on light field reconstruction characteristics of autostereoscopic three-dimensional display technologies

Multi-view technique, integral imaging, and holography are major techniques of autostereoscopic three-dimensional displays. In this presentation, we provide a comparative analysis on image characteristics of these autostereoscopic three-dimensional displays. Due to different optical configuration and light source coherency, these techniques reconstruct the desired light field with different spatial and angular sampling, which eventually affects the image quality and viewing limitations. By analyzing light field reconstructed by three techniques, it is expected that not only image characteristics of individual technique can be understood but also optimum technique for a given application can be identified.
Spot diffusing technique and angle diversity performance for high speed indoor diffuse infra-red wireless transmission

For future high-speed indoor wireless communication systems, spot diffusing techniques in an indoor nondirected diffuse channel draw great attention. In the paper, a novel spot diffusing configuration based on a line strip multibeam transmitter (LSMT) in association with an angle diversity receiver is used to improve the performance of optical wireless (OW) systems. The impact of both ambient light noise and multipath dispersion is investigated. Original results are presented evaluating and assessing the system performance when based on the proposed geometry, and comparison is carried out with four other geometries under the same conditions. The authors also compare the results of using the diversity detection with the spot diffusing technique and the case of no diversity with conventional diffuse systems where a single wide field-of-view (FOV) is used. The simulation results show that the performance improvement of the LSMT with a three direction diversity receiver is an enhancement of /spl sim/15 dB (signal-to-noise ratio) over the other conventional geometries in the presence of very directive noise sources and multipath dispersion. The RMS delay spread performance as well as the signal-to-noise ratio for the proposed configurations, at different positions on the communication floor (CF), are evaluated and compared.
Desempenho de enlace VLC com Modulação OOK e OFDM sob Condições Adequadas de Iluminação

Abstract —Visible light communications (VLC) transmit data through light emitting diodes. In this work, a VLC communication system is implemented with a commercial lamp composed of 7 white LEDs. The system includes the design-assembly of the electronic circuits of the transmission and reception front-ends. The different simulations carried out for an indoor environment show that VLC systems can transmit data while also maintaining the adequate lighting condition. OOK and OFDM modulations are used for the data transmission ( BER ≤ 10 − 3 for distances up to d ≥ 1 , 7 m). To characterize the illumination condition, photoradiometric measurements are made, ensuring adequate lighting up to 1,6 m.
Physical origin of negative differential resistance in SOI transistors

From a two-dimensional solution of Laplace's equation it is shown that a significant increase in temperature occurs in the channel of SOI transistors due to the relatively poor thermal conductivity of the buried insulator. Based on this simulation an equation is derived which predicts that at small channel lengths the pinchoft point is shifted, an effect which is consistent with experimental observations. In addition, the positive 'kink' is reduced with increasing gate voltage and this effect, together with the negative differential resistance, can be explained by a temperature increase in the channel.
Modeling the fringing electric field effect on the threshold voltage of FD SOI nMOS devices with the LDD/sidewall oxide spacer structure

This paper presents analysis of the fringing electric field effect on the threshold voltage of fully depleted (FD) silicon-on-insulator nMOS devices with the lightly doped drain (LDD)/sidewall oxide spacer structure based on a closed-form analytical model derived from the two-dimensional (2-D) Poisson's equation and using the conformal mapping technique. Based on the analytical model, as verified by the experimental data and the 2-D simulation results, with a lower n-LDD doping density, the fringing electric field effect in the sidewall oxide spacer lowers the short-channel effect.
Distributed Receding Horizon Coverage Control by Multiple Mobile Robots

This paper presents a distributed receding horizon coverage control algorithm to control a group of mobile robots having linear dynamics with the assumption that the robot dynamics are decoupled from each other. The objective of the coverage algorithm considered here is to maximize the detection of the occurrence of the events. First the authors introduce a centralized receding horizon coverage control and then they introduce a distributed version of it. To avoid the common disadvantages that are associated with the centralized approach, the problem is then decomposed into several RHCC problems, each associated with a particular robot, that are solved using distributed techniques. In order to solve each RHCC, each robot needs to know the trajectories of its neighbors during the optimization time interval. Since this information is not available, an algorithm is presented to estimate the trajectory of the neighboring robots. To minimize the estimation error, a compatibility constraint, which is also a key requirement in the closed-loop stability analysis, is considered. Moreover, the proof of the close-loop stability of this distributed version is provided and shows that the location of the robots will indeed converge to the centroids of a Voronoi partition. Simulation results validate the algorithm and the convergence of the robots to the centroidal Voronoi configuration.
Integral Sliding Mode Control Based Deadbeat Predictive Current Control for PMSM Drives With Disturbance Rejection

To promote the control performance of the modern high-precision permanent-magnet synchronous motor (PMSM) system on the existence of the time-delay and parameter mismatch, an improved deadbeat predictive current control (DPCC) method is proposed in this article. First, the conventional DPCC method considering the time-delay compensation is introduced. Along with this method, the negative influence on the control performance when the parameter mismatch occur is analyzed mathematically. Afterward, this article proposes a novel compensation scheme based on the integral sliding mode control (ISMC) theory for disturbance elimination. This proposed method incorporates the disturbance rejection term in the main control loop, which avoids the side effects of the traditional parallel external observer-based compensation method. The convergence of this disturbance rejection design is also proved. Meanwhile, the procedure of the ISMC-based DPCC method in digital implementation is illustrated and the resulting problems are discussed and solved. Furthermore, the chattering problem caused by the signum function is significantly suppressed by introducing the improved super-twisting algorithm combined method. Finally, experimental results confirm the validity of the proposed ISMC-based DPCC controller.
A compact low‐pass filter with ultrabroad stopband characteristics

A compact low‐pass filter (LPF) with ultrabroad stopband characteristic is presented in this article. This filter mainly consists of a rectangular stub resonator and cumulative open‐circuited stubs, providing multiple transmission zeros to form a wide stopband region. Further, two open stub loads are simply adopted to improve the band selectivity. This fabricated LPF exhibits a 3 dB cutoff frequency (fc) at 1.74 GHz with an average low insertion loss of 0.25 dB and a broad stopband region from 2.6 to 22.8 GHz (10.8ƒc) under a high rejection level of 20 dB. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:2800–2803, 2015
Simultaneous switching noise mitigation in high-speed circuits using complementary split-ring resonators

A novel concept for mitigating switching noise propagation in high-speed printed circuit boards is proposed. By etching complementary split-ring resonators (CSRRs) on only one metallic layer of the printed circuit board, the electric field between the power planes can be suppressed. This behaviour is in contrast to the split-ring resonator that suppresses the magnetic field. Furthermore, by cascading CSRRs, concentrically, a wide suppression of switching noise covering a wide frequency band from sub-gigahertz to 12 GHz is achieved. The effect of the new power-plane topology on the signal integrity is also investigated and analysed. It is shown that the CSRR would result not only in significant suppression of switching noise but also in robust signal behaviour.
Zero-current switching switched-capacitor quasiresonant step-down converter

Current stress is usually high for conventional switched-capacitor converter circuits, because of short-circuiting when charging up the capacitors. In this paper, two zero-current switching switched-capacitor resonant step-down converter families are presented which can improve the current stress problem. They are able to provide 1/2 to 1/n, and -1 to -1/n conversion ratios respectively by using only two switches. Principles of operation, computer simulation and experimental results of the proposed converters are presented. The measured efficiency is high and all parts of the circuits are under zero-current switching conditions.
Green supply chain practices and the selection of environmental technologies

The pressure on manufacturing organizations to adopt benign processes and to develop greener products has increased significantly over the last decade. As such, several manufacturing organizations have turned to their suppliers and customers to find innovative solutions to environmental issues. Using the data from a survey of the Canadian and United States package printing industry, the linkage between green supply chain practices and the selection of environmental technologies is examined. This paper differs from other studies that have linked supply chain management to environmental technologies as it focuses specifically on green interactions between organizations in the supply chain. In particular, the paper explores the possible relation between environmental collaboration and environmental monitoring in the supply chain and the form of environmental investment characterized by three categories: pollution prevention, pollution control, and management systems. The results suggest that environmental collaboration with suppliers is positively associated with greater investment in pollution prevention technologies while such collaboration with customers has no impact on the adoption and the implementation of pollution prevention technologies. In contrast, environmental collaboration with suppliers is associated with fewer investments in management systems. Overall, green supply chain practices with customers have very little impact on environmental investment decisions.
An approximate analytical solution to the pull-in voltage of a micro bridge with an elastic boundary

This paper derives an approximate analytical solution to the pull-in voltage of a micro bridge with elastic boundaries. The analytical model considers the elastic boundary effect, fringing field capacitance, residual stresses and the distributed flexibility of the bridge. The accuracy of the present approximate analytical solution is verified by comparison with the simulation results of commercial FEM packages and other published closed-form solutions as well as experimental measured data. The deviation of the present approximate analytical solution is within 5% for a wide beam and a narrow beam in a small deflection regime. The present approximate analytical solution has explicit physical meaning and is highly accurate for device design.
More risks or/and more benefits? Prospect theory application to the analysis of the bio wines evolution in France

Purpose: In the last five years the conversion of vineyards to organic or bio vineyards accelerates all over France, the annual rate of conversion varies between 20-25% per year since 2006. It becomes even more striking as the total surface of vineyards in France reduces. Our work focuses first on understanding the main reasons and difficulties of the conversion process into organic vineyards (which takes three years), in particular in Bordeaux region. Methodology: We examine the risky choices of winemakers using the prospect theory to explain the various outcomes. We put forward a simple model describing how winemakers make choices in situations where they have to decide between alternatives "bio or not bio" ; "bio certified or not certified", "reasonable use of chemicals" ( agriculture raisonnable) that involve several risks and will impact their financial situation. We introduce and compute a value function, based on the potential outcomes and their respective probabilities, and then choose the alternative having a higher utility. Findings: Our results point to reference-dependent choice theories such as prospect theory, and suggest that path-dependence is relevant; the concavity of the value function in gains can lead to a low preference for converting into organic farming even when the choice problems
Inflammatory myoglandular polyp as a cause of recurrent abdominal pain in a patient with quiescent Crohn’s disease

Chronic inflammation of the intestinal mucosa has been associated with the appearance of inflammatory polyps or pseudopolyps. Among the distinct categories of inflammatory polyps are inflammatory myoglandular polyps (IMGP) usually found in the colorectum. Only one case of IMGP in the terminal ileus has been described since their first description. We report the first case of an inflammatory polyp with both hyperplastic and myoglandular histological characteristics, in the terminal ileum of a patient with quiescent Crohn’s disease, causing recurrent intussusception.
Service models and realization of differentiated services networks

Internet Service Providers need to offer Quality of Service (QoS) to fulfil the requirements of applications of their customers. Moreover, in a competitive market environment costs must be low. The selected service model must be effective and low in complexity, but it should still provide high quality and service differentiation, that the current Internet is not yet capable to support. The Differentiated Services (DiffServ) Architecture has been proposed for enabling a range of different Classes of Service (CoS). In the EURESCOM project P1006 several European service providers co-operated to examine various aspects involved in the introduction of service differentiation using the DiffServ approach. The project explored a set of service models for Expedited Forwarding (EF) and Assured Forwarding (AF) and identified requirements for network nodes. Besides, we addressed also measurement issues, charging and accounting issues. Special attention has been devoted to requirements of elastic traffic that adapts its sending rate to congestion state and available bandwidth. QoS mechanisms must prove Transmission Control Protocol (TCP) friendliness. TCP performance degrades under multiple losses. Since RED based queue management may still cause multiple discards, a modified marking scheme called Capped Leaky Bucket is proposed to improve the performance of elastic applications.
Low-cost compact PM machine for adjustable-speed pump application

A variable-speed driven pump can result in significant energy conservation where reduced flow rates are required for long periods of time. Concerning adjustable-speed pump drives, one major contribution of this paper is to show that a permanent magnet motor based on the slotless axial-flux PM machine (AFPM) topology can be a suitable candidate to advantageously compete with the induction motor for such a low-cost drive application. To the purpose of a cost comparison, the paper discusses the design and construction of a prototype machine which has been conceived to replace a 1.2 hp induction motor being used in a standard adjustable-speed pump drive. Results taken from laboratory tests of the prototype machine are reported together with an assessment of the machine manufacturing cost.
Individual determinants of COVID-19 vaccine hesitancy

Background Novel coronavirus disease 2019 (COVID-19) vaccine hesitancy is a barrier to achieving herd immunity, and thus, a prominent public health concern. This study aimed to identify the determinants of COVID-19 vaccine hesitancy based on the World Health Organization’s ‘3Cs’ model (i.e., confidence, complacency, and convenience) in the United States (U.S.) and Canada. Methods Data from 7678 adults ages 18 or older were collected from the four most populous U.S. States, specifically New York, California, Florida, and Texas, and from English-speaking Canada at three timepoints, in May and July 2020, and March 2021 using a web-based survey (www.covid19-database.com). Sociodemographic information was collected, and comprehensive psychological assessments were administered. Univariate analyses were performed to identify the individual determinants of vaccine hesitancy, which were categorized as: 1) vaccine confidence, 2) vaccine complacency, 3) sociodemographic, and 4) other psychological factors. A series of models were computed using these categorizations. Results Mistrust of vaccine benefit (β(SE) = 0.67(0.01), p<0.001, partial η2 = 0.26) and lower perceived seriousness of COVID-19 (β(SE) = 0.68(0.02), p<0.001, partial η2 = 0.12) were the principal determinants of vaccine hesitancy. Right-wing political affiliation (β(SE) = 0.32(0.02), p<0.001, partial η2 = 0.03), higher risk propensity (β(SE) = 0.24(0.02), p<0.001, partial η2 = 0.03), and less negative mental health effects of the COVID-19 pandemic (β(SE) = 0.20(0.01), p<0.001, partial η2 = 0.03) were the main sociodemographic and psychological determinants. Other sociodemographic determinants included younger age, women, race, and employment status. Lack of vaccine confidence and complacency explained 38% and 21% of the variance in vaccine hesitancy, respectively; whereas, sociodemographic and psychological determinants explained 13% and 11% of the variance in vaccine hesitancy, respectively. Discussion Targeted and tailored public health interventions that enhance the public’s confidence in vaccines and emphasize the risk and seriousness of COVID-19 may address COVID-19 vaccine hesitancy. Efforts directed toward specific marginalized and underserved groups may be required to promote vaccine confidence.