Miracle-dz/UniFAR-FTUs huggingface dataset:
Elevation and Azimuth Direction Finding by Two-Element Pattern Reconfigurable Antenna Array

An elevation and azimuth direction-finding (DF) method is presented by introducing the pattern reconfigurable antenna (PRA) into a two-element array. An equivalent multi-dimensional array is built by the two-element PRA array with switchable beams of same or opposited directions. With the introduction of same-direction and opposite-direction modes of PRAs, the elevation and azimuth angles are estimated by the methods of time modulated array (TMA) and amplitude comparison, respectively. Meanwhile, a 2-D look-up table is built to correct the coning-error effect of the amplitude comparison. Compared with the conventional 2-D DF method with two orthogonal linear arrays, only a single linear array with not less than two elements is needed in the proposed method. Hence, it has the advantages of simple structure, compact size, and low cost. Simulated results are provided to verify the proposed 2-D DF method, and an S-band two-element PRA array is constructed to demonstrate its experimentally feasibility.
MCT (HgCdTe) IR detectors: latest developments in France

This paper presents an overview of the very recent developments of the MCT infrared detector technology developed by CEA-LETI and Sofradir in France. New applications require high sensitivity, higher operating temperature and dual band detectors. The standard n on p technology in production at Sofradir for 25 years is well mastered with an extremely robust and reliable process. Sofradir's interest in p on n technology opens the perspective of reducing dark current of diodes so detectors could operate in lower flux or higher operating temperature. In parallel, MCT Avalanche Photo Diodes (APD) have demonstrated ideal performances for low flux and high speed application like laser gated imaging during the last few years. This technology also opens new prospects on next generation of imaging detectors for compact, low flux and low power applications. Regarding 3rd Gen IR detectors, the development of dual-band infrared detectors has been the core of intense research and technological improvements for the last ten years. New TV (640 x 512 pixels) format MWIR/LWIR detectors on 20μm pixel pitch, made from Molecular Beam Epitaxy, has been developed with dedicated Read-Out Integrated Circuit (ROIC) for real simultaneous detection and maximum SNR. Technological and products achievements, as well as latest results and performances are presented outlining the availability of p/n, avalanche photodiodes and dual band technologies for new applications at system level.
Determination of current waveforms for torque ripple minimisation in switched reluctance motors using iterative learning: an investigation

The paper deals with the investigations on an iterative learning approach to determine the desired current waveforms for switched reluctance motors, which give rise to ripple-free torque. The current waveforms are generated by repeated corrections from iteration to iteration starting from the conventional rectangular pulse profile as the initial waveform. The scheme requires much less a priori knowledge of the magnetic characteristics of the motor. The algorithms have been formulated for both one-phase-on and two-phase-on schemes, for a four-phase switched reluctance motor, in the light of the principles behind iterative learning. Based on the observations from the simulation results of these schemes, a modified scheme has been proposed by incorporating a suitable commutation process, often called torque sharing functions, in order to generate reasonably smooth current waveforms for the ease of tracking by the stator circuit of the motor. The performances of all the proposed schemes have been verified by computer simulation.
Contactless technologies adoption during the coronavirus pandemic: a combined technology acceptance and health belief perspective

ABSTRACT The ongoing COVID-19 pandemic and safe social distancing measures have engendered a surge of interests in contactless technology applications. While social distancing might become a long-term practice and consumers are adapting to the new lifestyle, behavioural research is needed to promote consumers’ adoption of contactless technologies. The objective of this study is to investigate the psychological determinants of emerging contactless technologies by synthesising theoretical insights from two behavioural precepts: (i) health belief model comprising constructs such as perceived severity, perceived susceptibility, cues to action, self-efficacy, and (ii) technology acceptance model consisting of constructs such as perceived usefulness and perceived ease of use. A questionnaire survey is conducted to collect data from 508 consumers. The data are analysed using confirmatory factor analysis and structural equation modelling. The results show that health belief factors and technological characteristics contribute to the willingness to adopt contactless technologies. This research enriches behavioural research by providing a coherent and fitting explanation on consumers’ acceptance of contactless technologies. Practically, strategy implications regarding innovation-supportive environment creation, resources and training provision and end-customer demand satisfaction are provided to support contactless technology adoption.
FULL SCALE VIV RESPONSE MEASUREMENTS OF A DRILL PIPE IN GULF OF MEXICO LOOP CURRENTS

In September 2004 BP retrieved a Gulf of Mexico drilling riser due to excessive loop currents. Whilst waiting for the currents to diminish an impromptu full scale riser Vortex Induced Vibrations (VIV) test was carried out using the drilling riser standalone monitoring system. A 6-5/8 inch drill pipe was instrumented and deployed under the drilling vessel to a depth of 1,000ft. The drilling vessel drift was varied relative to the loop current to produce a range of current profiles and surface current speeds. Current loading along the length of the drill pipe was measured using the on-board acoustic doppler current profiler (ADCP). The paper describes the test set-up and measured VIV response. It includes observations of cross flow VIV, in-line VIV and additional response at higher frequencies not currently predicted with industry VIV analysis tools.
SiGe base bipolar technology with 74 GHz f/sub max/ and 11 ps gate delay

An epitaxial SiGe-base bipolar technology suited for very high performance mixed digital/analogue applications is presented. A key feature is the emitter/base process which is the obvious SiGe-base extension of the implanted base double-poly self-aligned emitter/base structure. The fabricated HBTs exhibit a maximum cut-off frequency f/sub T/ of 61 GHz, a maximum oscillation frequency f/sub max/ of 74 GHz and a record CML gate delay time of 11 ps.
The climatology of extreme wildfires in Portugal, 1980–2018: Contributions to forecasting and preparedness

Available research has extensively examined the spatiotemporal patterns of fire‐weather regime in Portugal, but a comprehensive climatology of extreme wildfires is still under development. This study calls for different strategies and scales of analysis aiming to describe the relationships between medium and low troposphere weather conditions and severe fire behaviour in mainland Portugal, between 1980 and 2018. In particular, critical fire‐weather patterns and thresholds that can contribute to operational and forecasting know‐how in short and medium time ranges are presented. We updated the general trends in the fire regime with a new, longer daily burned area series and developed a method that identifies Extreme Wildfire Periods (EWP) that form the basis for climate analysis. Synoptic analysis using Circulation Weather Types (CWT) showed that the northeasterly and easterly directional flows are significantly associated with EWP and produce the most severe fire‐weather conditions. The four main CWT related to extreme fire are driven from anticyclones over the eastern Atlantic between the Azores and the British Isles. However, severe situations can also be regulated by CWT with marginal presence in both summer and EWP: low systems located to the west and northwest of Iberia carrying air masses from the south quadrant are related to catastrophic events. Regarding the antecedent climate, the results indicate that the coincident meteorological drought, whether weak or intense, is a necessary but not sufficient condition for the development of an EWP. An increasing relevance of water stress for shorter intervals preceding EWP, in the order of days and weeks, is apparent. Following these results, fine dead fuel moisture thresholds related to transitions in fire behaviour in Portuguese landscapes are computed using a promising predictive moisture content model. Finally, the different methods used are summoned for the detailed analysis of an EWP starting under unusual synoptic circulation.
Workplace experiences of physical educators with and without National Board Certification

Physical educators tend to be perceived as teachers of a non-core, ancillary subject, meaning that they often contend with marginalization. In previous research, physical education National Board Certified Teachers (NBCTs) reported enhanced self-efficacy and confidence in their teaching with reduced feelings of marginality. Nevertheless, direct comparisons between the perceived workplace experiences of physical education NBCTs and non-NBCTs have not yet been made. The purpose of the current investigation was to examine the workplace experiences of physical education NBCTs and non-NBCTs while accounting for teaching level. A recruitment email was sent to 500 physical education NBCTs and 420 physical education non-NBCTs. Using a case–control design, 74 NBCTs were selected and matched with 74 non-NBCTs. A 2 × 2 factorial MANCOVA test, a univariate ANCOVA test, and an independent-samples t-test were used in data analysis. Results indicated that the main effect for NBCT status was significant. Specifically, NBCTs felt less isolated than their non-NBCTs counterparts. NBCTs generally perceived that they mattered more than non-NBCTs, especially at the secondary level. Additionally, teachers with NBCT certification reported higher levels of role conflict and role overload than those participants without NBCT status. This study highlights important connections between NBCT status and teachers’ workplace experiences that both relate to and extend previous research. Future scholars should consider seeking to understand the mechanisms that underlie reported differences between NBCTs and non-NBCTs.
The Use of Bottom Ash in the Design of Dams

The design of dams requires selecting materials that possess engineering properties that allow a structure to perform in a reliable and safe fashion while allowing their construction to be carried out within the economic and time constraints of a project. The selected materials need to exhibit: high shear strength, unit weights that limit the loading on the foundation soils, and compressibility characteristics that minimize total and differential settlement. Permeability and grain-size characteristics of the selected materials determine their location within the cross-section of a dam. Bottom ash, a by- product of burning coal at a power plant, is a material that exhibits high shear strength, low compressibility, and relatively low unit weight. These engineering properties make bottom ash an ideal material in the design and construction of dams. Bottom ash also exhibits a relatively high permeability and a grain-size distribution that allows the design engineer to use it in direct contact with impervious materials and/or toe drains and to meet well established filter and piping criteria. The work presented herein describes the engineering properties of the bottom ashes that led to their selection in the design of the dams that form Horse Ford Creek Fly Ash Reservoir in Kentucky, Muskingum River Plant Upper Reservoir in Ohio, and Tanners Creek Fly Ash Pond in Indiana. These facilities are currently under construction. The bottom ash has proved to be an economical material because it has demonstrated to have good engineering properties and to be available near the project location.
Analysis of loop antenna with circular reflector and its properties

The method of equivalent edge currents is applied to derive diffraction fields by an edge of a cone conductor. Geometrical-optical fields (direct wave + reflected wave) are added to the diffraction fields and both fields are Fourier analyzed to find current distirbutions and input impedance. Radiation pattern and power gain are obtained in terms of diffraction coefficients derived by Kouyoumjian et al. Calculations are made mainly for a one-wavelength loop antenna and the effects of the disk reflector diameter and wedge angle are clarified. The power gain is 1 dB larger than that of an infinite plane reflector. Theoretical results generally agree with observations.
Effects of flipped instruction on iranian intermediate EFL learners’ speaking complexity, accuracy, and fluency

Abstract This study examined the effects of using flipped instruction on Iranian EFL learners’ speaking complexity, accuracy, and fluency (CAF). To fulfill this objective, the Oxford Quick Placement Test (OQPT) was administered to 96 Iranian EFL learners and 60 of them who were at the intermediate level were selected as the target participants of this study. Then, the selected participants were divided into two groups of experimental (n = 30) and control (n = 30). After that, the participants of both groups were given a speaking pre-test. Subsequently, the experimental group received the instruction through flipped instruction while the control group was instructed in a traditional classroom. After the treatment, a questionnaire related to the learners’ attitudes towards using flipped instruction was distributed among the participants of the experimental group to investigate their ideas about using flipped instruction. The findings of Independent Samples T-test and Paired Samples T-test revealed that there was a significant difference between the post-tests of the experimental and the control groups in the favor of the experimental group. In fact, the results indicated that the experimental group significantly outperformed the control group on the post-test . Moreover, the findings of One-Sample T-Test showed that Iranian EFL learners had positive attitudes towards using flipped instruction for speaking classes. The findings of this study can encourage English teachers to use flipped instruction in their classes to reach better learning results. In addition, this study may enrich the related literature by encouraging researchers to pay more attention to the impacts of the flipped instruction on developing EFL and ESL learners’ speaking skill.
ESG Scores and Bank Performance During COVID-19

This chapter examines the impact of ESG scores on bank stock returns as a response to the COVID-19 pandemic. The authors use a sample of 73 publicly listed banks from 15 developed European countries. They perform the analysis using two different periods that cover the pandemic: the first major wave period of COVID-19 (February-April 2020) and an extended period (February 2020-April 2021). The findings reveal the negative influence of the COVID-19 pandemic on bank stock returns during the first wave of the pandemic. They further find that, during the first wave, stock returns of banks with higher ESG scores were more resilient to the pandemic. However, when they use the extended time period (from February 2020-April 2021), the influence of both COVID-19 and ESG scores becomes insignificant. The chapter's findings have important policy implications during unprecedented crisis times such as COVID-19.
Corporate governance and voluntary disclosure: The case of listed firms on the Athens Stock Exchange

This paper explores the effect of corporate governance on voluntary disclosure. The investigation of the research question was based on hand-collected data from annual reports for a sample of 93 non-financial listed firms on the Athens Stock Exchange for 2017. Using several items to create a voluntary disclosure index, the authors investigate the arguments that ownership structure, board of directors (board) and audit committee affect voluntary disclosure. The results indicate that some corporate governance characteristics (block ownership and board independence) reduce voluntary disclosure, while others (board and audit committee size) increase the extent of disclosure. Additionally, a positive effect on the voluntary disclosure concluded for the size of the firm and the size of the audit firm. The results have implications for capital market regulators and listed firms wishing to reduce conflicts between the firm and its related parties and to strengthen the confidence to the firm’s governance by using corporate governance structures. This paper contributes to the academic debate on the relationship between corporate governance and voluntary disclosure by assessing the effect of ownership structure, board of directors (board) and audit committee on the extent of voluntary disclosure. Key words: Corporate governance, disclosure, voluntary disclosure, ownership, board of directors, audit committee.
Conceptual Full-Vehicle Development supported by Integrated Computer-Aided Design Methods

AbstractToday’s automotive industry is characterized by a high product diversification in combination with decreasing times-to-market. This leads to high demands on product development processes and assumes the application of multidisciplinary and flexible virtual product development tools and methods. The present publication introduces to the challenges of conceptual full-vehicle development and discusses the ability of applying a centralized product master model by an exemplarily illustration of a 3D- CAD approach. As a key aspect of this publication, a method for the support of geometrical full-vehicle development processes (e.g. geometrical integration, vehicle packaging) during early product generation phases is presented and discussed in detail.
Suppression of drum brake squeal through structural modifications using finite element method

Reducing squeal from brakes system has become a challenging task for brake engineers. To date, a large number of proposals have been implemented in tackling disk brake squeal but very few solutions have been forwarded in drum brake assembly. This paper attempts to propose a solution to reduce drum brake squeal through structural modifications by using the Finite Element (FE) method. A three-dimensional FE model of an actual drum brake system is developed and validated. First, the baseline FE model is simulated to predict squeal and then several structural modifications are proposed. Finally, dynamic transient analysis is performed for selected modified models in order to confirm predicted results obtained from complex eigenvalue analysis.
RATIONALIZATION AND DECONCENTRATION OF THE U.S. CONTAINER PORT SYSTEM

The recent development of intermodal transportation and the relaxation of U.S. transport regulations have encouraged ocean carriers to rationalize their port schedules. Container shipping is therefore believed to concentrate shipping at a few large ports. Port traffic analysis, using the Lorenz Curve and Gini Coefficient, reveals, nevertheless, that the structure of the U.S. port system is actually becoming less concentrated. The challenge of secondary ports and changes in the transportation system explain this deconcentration.
Translation and validation of the Dutch version of the Birth Satisfaction Scale-Revised (BSS-R)

ABSTRACT Background Recent observations suggest birth satisfaction may be significantly associated with postpartum post-traumatic stress disorder (PP-PTSD). The Birth Satisfaction Scale-Revised (BSS-R) is increasingly used Internationally as a short, valid and reliable multi-dimensional measure of birth experience. The current study sought to develop a Dutch version of the BSS-R (D-BSS-R) for clinical and research application in the Netherlands. Methods Post-translation, a cross-sectional design with an embedded between-subjects component was used to evaluate key indices of validity and reliability of the D-BSS-R in a purposive sampled cohort of 244 Dutch-speaking women in the Netherlands. Confirmatory factor analysis, divergent, convergent and known-groups discriminant validity were evaluated as was the internal consistency of the measure. Results The D-BSS-R was found to be a generally valid and reliable measure of birth experience with the key measurement characteristics of the original English-language measure transferring well to the Dutch context. Statistically significant negative correlations were observed between all D-BSS-R sub-scales and a validated measure of PTSD. Conclusions The D-BSS-R represents a valid and reliable measure of birth experience suitable and appropriate for use in the Netherlands. The study corroborates previous suggestions of linkage between birth satisfaction and PP-PTSD using a robust and diagnostically valid measure of trauma.
SPICE Modeling of polysilicon thermal actuators

This paper reports on modeling the behavior of micromachined polysilicon thermal actuators. The thermal actuators used in this research were fabricated using the DARPA-sponsored multi-user MEMS processes. Data collected in both air and vacuum demonstrates that thermal actuators can be controlled and positioned using a pulsed input with a period much less than the thermal time constant of the device. Both pulse width and pulse amplitude modulation have been successfully employed to position lateral actuators, lateral actuator arrays, and piston micro-mirrors. In order to better exploit the power averaging characteristics of thermal actuators, SPICE models for polysilicon thermal actuators were developed using relationships between resistance, deflection, and average power. These models incorporate the polysilicon thermal actuators electrical load and transient characteristics necessary for predicting actuator performance and developing CMOS drive circuits. The SPICE models exhibit good agreement with theory and measured performance of the polysilicon thermal actuators.
Nonlocal balance equations with parameters in the space of signed measures

A parametric family of nonlocal balance equations in the space of signed measures is studied. Under assumptions that cover a number of known conceptual models we establish the existence of the solution, its uniqueness and continuous dependence on the parameter and the initial distribution. Several corollaries of this theorem, which are useful for control theory, are discussed. In particular, this theorem yields the limit in the mean field of a system of ordinary differential equations, the existence of the optimal control for an assembly of trajectories, Trotter’s formula for the product of semigroups of the corresponding operators, and the existence of a solution to a differential inclusion in the space of signed measures. Bibliography: 33 titles.
Multilayer Memristive Neural Network Circuit Based on Online Learning for License Plate Detection

The analog circuit design of the memristive neural network (MNN), which can automatically perform the online learning algorithm, is an open question. In this article, a memristive self-learning neuron circuit for implementing the online least mean square (LMS) algorithm is designed. Extending on the designed neuron circuit, the circuit implementation of the monolayer and multilayer neural network is proposed. The proposed neural network can automatically converge the output to the set target according to the input. The application-level validations of the circuits are done using pattern recognition and license plate detection. The performances of the designed MNN circuits and the effect of memristive variation are analyzed through PSPICE simulations. The learning accuracy of the proposed circuit for license plate detection can reach 93%. Circuit simulation results reveal that the proposed MNN circuits can accelerate the training speed and have the tolerance to the variations of the memristor.