Miracle-dz/UniFAR-FTUs huggingface dataset:
Determining ultrasonic propagation effective properties in complex heterogeneous media through microstructure-scale simulation

Ray-based methods allow for fast computations of ultrasonic propagation in large components, and can be coupled with diffraction models to provide full simulations of NDE inspections. However, they do not account for complex interactions with highly heterogeneous propagation media, which can have a significant impact on inspection performances. In contrast, microstructure-scale finite element simulations consider these interactions but are too computationally intensive for large-scale simulations. The work presented in this communication aims at combining the advantages of these two approaches. On the one hand, finite element simulations for small volumes of the microstructure are used to determine parameters such as effective velocities, attenuations, and scattering coefficients. On the other hand, a ray-based model uses these data to compute wave propagation over distances that are large compared to both wavelengths and characteristic microstructure sizes. A dedicated simulation module has been implemented in a development version of the CIVA software. It generates random realizations of microstructures for given set of parameters, runs finite element computations, and post-processes their results to yield estimations of the properties of the macroscopic effective medium. The volumes considered by the finite element model are small enough to allow for 3D computations. Results were obtained for various types of microstructures, describing metals or concrete. This communication focuses on steel applications that were the focus of collaborative studies between CEA and EDF. The approach is promising, and contributes to bridging the gap between microstructure-scale modelling and larger scale simulations.
Intensity correlations near a cavity QED antiresonance

We explore the antiresonance phenomenon, where a two-level atom is excited inside a single-mode, laser-driven cavity without appreciably exciting the field mode. Antiresonance is well known in classical physics and the excitation of the atomic and field degrees of freedom by a weak laser field can be easily understood in a classical oscillator picture. The temporal intensity correlations in the signal emitted from the atom and from the cavity, however, show strong signs of nonclassical behavior. We calculate these correlations and show how they can be interpreted in terms of a conditional quantum trajectory dynamics of the system.
On lower bounds using separable terms in interval B&B for one-dimensional poblems

Interval Branch-and-Bound (B&B) algorithms are powerful methods which aim for guaranteed solutions of Global Optimization problems. Lower bounds for a function in a given interval can be obtained directly with Interval Arithmetic. The use of lower bounds based on Taylor forms show a faster convergence to the minimum with decreasing size of the search interval. Our research focuses on one dimensional functions that can be decomposed into several terms (sub-functions). The question is whether using this characteristic leads to sharper bounds when based on bounds of the sub-functions. This paper deals with separable functions in two sub-functions. The use of the separability is investigated for the so-called Baumann form and Lower Bound Value Form (LBVF). It is proven that using the additively separability in the LBVF form may lead to a combination of linear minorants that are sharper than the original one. Numerical experiments confirm this improving behaviour and also show that not all separable methods do always provide sharper additively lower bounds. Additional research is needed to obtain better lower bounds for multiplicatively separable functions and to address higher dimensional problems.
Phytoplankton community response to episodic wet and dry aerosol deposition in the subtropical North Atlantic

Atmospheric aerosol deposition into the low latitude oligotrophic ocean is an important source of new nutrients for primary production. However, the resultant phytoplankton responses to aerosol deposition events, both in magnitude and changes in community composition, are poorly constrained. Here, we investigated this with 19 d of field and satellite observations for a site in the subtropical North Atlantic. During the observation period, surface dissolved aluminum concentrations alongside satellite‐derived aerosol and precipitation data demonstrated the occurrence of both a dry deposition event associated with a dust storm and a wet deposition event associated with strong rainfall. The dry deposition event did not lead to any observable phytoplankton response, whereas the wet deposition event led to an approximate doubling of chlorophyll a, with Prochlorococcus becoming more dominant at the expense of Synechococcus. Bioassay experiments showed that phytoplankton were nitrogen limited, suggesting that the wet deposition event likely provided substantial aerosol‐derived nitrogen, thereby alleviating the prevalent nutrient limitation and leading to the rapid observed phytoplankton response. These findings highlight the important role of wet deposition in driving rapid responses in both ocean productivity and phytoplankton community composition.
Synthesis, characterization, electrical and sensor behavior of PANI/In2O3 nano composites

ABSTRACT Indium oxide (In2O3) nanoparticles were successfully prepared by sol-gel method. Nanocomposites of polyaniline (PANI) and Indium oxide (In2O3) have been synthesized using insitu polymerization method for different concentrations of nano In2O3 powder. The formation of polymer nanocomposite and changes in its structural and micro structural properties of the materials were investigated by X-ray diffractometry (XRD) and Fourier infrared spectroscopy (FTIR) techniques. The surface morphology of PANI–In2O3 nanocomposite was elucidated using Scanning Electron Microscopy (SEM). DC conductivity studies of PANI-In2O3 composites for different weight percentage (wt%) show thermally activated behaviour. The conductivity was found to increase with the increase in temperature indicating the semiconducting behaviour of all the compositions. Maximum conductivity was observed in 30 wt% of In2O3 in polyaniline. On exposure of the composites to liquefied petroleum gas (LPG), increase in resistance was observed with the increase in gas concentration. Maximum sensitivity for gas sensing was observed in the composite of 50 wt% In2O3 in polyaniline.
A Study of the Kepler K2 Variable EPIC 211957146 Exhibiting a Variable O’ Connell Effect

We present the multi-band photometric and spectroscopic study of an over-contact binary system, EPIC 211957146. The light curves exhibit a variable O’ Connell effect, confirmed from our observational data and the Kepler K2 data. The best photometric solution incorporating a dark spot over the primary component unveils that the system has a low-mass ratio (q ∼ 0.17) and a high inclination (i ∼ 85°). To confirm the solution and constrain the uncertainty, Monte-Carlo simulations are performed and the results are reported. Based on the O–C diagram analysis, we see that the variable shows a period increase at the rate of dP/dt ∼ 1.06 × 10−6 days yr−1, which is higher than the theoretically predicted value. Presence of a third body having a period of ∼16.23 years is evident from the O–C diagram. No filled-in effect is observed in the Hα line, while the effect is vividly present in the Na line. From the Kepler K2 data, we found that the primary and secondary minima exhibit an anti-correlated O–C variation followed by an erratic behavior. This is possibly caused by the longitudinal motion of the spot, and hence, we set a lower limit of ∼40 days for the spot modulation. We also observe a possibly associated photometric difference in the primary depth by comparing our light curves with Kepler K2 normalized light curves. This system has a low-mass ratio and a high fill-out factor, and, theoretically, such a physical configuration would lead to a merger.
Insularity determines nestling sex ratio variation in Egyptian vulture populations

Abstract Variation in offspring sex ratio, particularly in birds, has been frequently studied over the last century, although seldom using long‐term monitoring data. In raptors, the cost of raising males and females is not equal, and several variables have been found to have significant effects on sex ratio, including food availability, parental age, and hatching order. Sex ratio differences between island populations and their mainland counterparts have been poorly documented, despite broad scientific literature on the island syndrome reporting substantial differences in population demography and ecology. Here, we assessed individual and environmental factors potentially affecting the secondary sex ratio of the long‐lived Egyptian vulture Neophron percnopterus. We used data collected from Spanish mainland and island populations over a ca. 30‐year period (1995–2021) to assess the effects of insularity, parental age, breeding phenology, brood size, hatching order, type of breeding unit (pairs vs. trios), and spatial and temporal variability on offspring sex ratio. No sex bias was found at the population level, but two opposite trends were observed between mainland and island populations consistent with the island syndrome. Offspring sex ratio was nonsignificantly female‐biased in mainland Spain (0.47, n = 1112) but significantly male‐biased in the Canary Islands (0.55, n = 499), where a male‐biased mortality among immatures could be compensating for offspring biases and maintaining a paired adult sex ratio. Temporal and spatial variation in food availability might also have some influence on sex ratio, although the difficulties in quantifying them preclude us from determining the magnitude of such influence. This study shows that insularity influences the offspring sex ratio of the Egyptian vulture through several processes that can affect island and mainland populations differentially. Our research contributes to improving our understanding of sex allocation theory by investigating whether sex ratio deviations from parity are possible as a response to changing environments comprised by multiple and complexly interrelated factors.
Formation of periodic zigzag patterns in the twist-bend nematic liquid crystal phase by surface treatment

ABSTRACT Zigzag patterns were successfully generated in the twist-bend nematic (NTB) phase of 1-(4-cyanobiphenyl-4′-yl)-6-(4-cyanobiphenyl-4′-yloxy)hexane (CB6OCB) via simple surface treatment. A detailed microscopy study using polarised optical microscopy and fluorescence confocal polarising microscopy was performed to observe the director arrangement in the zigzags, where distinctive periodic patterns were found to be aligned perpendicular to the rubbing direction. These patterns originate from the structural instability and generation of splay deformation with focal conic domain-like structures that are typically found in smectic phases, revealing that the NTB phase has physical properties similar to those of the smectic phase. Observation of these unusual zigzag patterns in the NTB phase opens an avenue for use of this phase in potential applications such as optical modulators and gratings. GRAPHICAL ABSTRACT
Extensive reading research: What have we learned and what questions remain?

Research to date suggests that extensive reading (ER) can help develop learners’ language competence. Students who read a great deal in the target language are more likely to develop a higher overall proficiency. This article aimed to examine the extent, range, and nature of research activities on ER and identify gaps in the existing literature on the effects of ER on language learning. To identify relevant studies, EBSCOhost, ProQuest, and Web of Science databases were searched using the following search terms: extensive reading or graded readers or free voluntary reading (TI) and extensive reading or graded readers or free voluntary reading (AB). A total of 109 studies published from 2001– 2021 were then analysed to determine the characteristics and emergent themes of prior studies on ER. Our analysis revealed that the existing studies placed greater emphasis on improving learners’ reading attitudes than learners’ linguistic abilities and language use (e.g., speaking and writing skills). Given the potential impact of ER on students’ overall language development, not just increased reading proficiency and skills, the ER research base should be substantially expanded so that we know more about its effects on diverse aspects of language learning.
An Action Research on Improving Environmental Sensitivity of Fourth Grade Primary School Students: What Happens in the School Garden?

School gardens, which play an important role in environmental education, provide an opportunity for students to develop environmental awareness and gain environmental responsibility. In this study, which draws attention to this, it is aimed to reveal the applicability of the workshops prepared in the school garden in order to improve the environmental sensitivity of the students. The research was carried out with 10 female and 10 male 4th grade students in a public primary school in the city center of Bartin in the 2021-2022 academic year. The research was carried out with the action research design, one of the qualitative research methods. The data of the research were obtained through a scale developed by Peker (2020) and a semi-structured interview form prepared by the researchers. Quantitative data obtained using descriptive statistics and dependent group t-test statistical procedures; qualitative data were analyzed with content analysis technique. As a result of the research, it has been determined that environmental education workshops are effective in increasing students’ environmental awareness. Students stated that environmental education activities are fun, useful and instructive. As a result, it is seen that the workshops applied in the school garden increase the environmental awareness of the 4th grade students and the process has a positive effect on them. As a result of the research, it can be suggested that environmental awareness should be brought to students through school gardens and reflected in educational environments by organizing various activities that encourage positive attitudes.
Using DICONDE for NDT Data Exchange

The processing of multiple data sets from different NDT vendors and systems can be challenging. Accessing the data requires dealing with different and often proprietary data formats. In addition to that the correct spatial alignment requires knowledge and information about the acquisition system and must consider different approaches for markers and reference coordinate systems. The key features of NDE 4.0 and digital twin concepts are storage and interoperability with standard data formats. In this example data from thermography, manual ultrasonic testing and immersion ultrasonic testing are considered. For established devices multiple tools exist for the conversion of data into image-based formats. However, besides the lack of spatial alignment there is a need to access the raw data for further processing. In medical and CT-like applications the DICOM format has become a widely used exchange format. Its derivative DICONDE transfers this into the field of NDT. This study demonstrates the use of this format for data processing from multiple NDT methods and addresses issues related to interoperability and the integration of less structured data from inspections.
Magnetic resonance coronary vessel wall imaging with highly efficient respiratory motion correction

There is a need for a noninvasive imaging technique for use in longitudinal studies of sub-clinical coronary artery disease. Magnetic resonance (MR) can be used to selectively and non-invasively image the coronary wall without the use of ionising radiation. However, high-resolution 3D studies are often time consuming and unreliable, as data acquisition is generally gated to a small window of diaphragm positions around end-expiration which results in inherently poor and variable respiratory efficiency. This thesis describes the development and application of a novel technique (beat-to-beat respiratory motion correction (B2B-RMC)) for correcting respiratory motion in 3D spiral MR coronary imaging. This technique uses motion of the epicardial fat surrounding the artery as a surrogate for the motion of the artery itself and enables retrospective motion correction with respiratory efficiency close to 100%. This thesis first describes an assessment of the performance of B2B-RMC using a purpose built respiratory motion phantom with realistic coronary artery test objects. Subsequently, MR coronary angiography studies in healthy volunteers show that the respiratory efficiency of B2BRMC far exceeds that of conventional navigator gating, yet the respiratory motion correction is equally effective. The performance and reproducibility of 3D spiral imaging with B2B-RMC for assessment of the coronary artery vessel wall is subsequently compared to that of commonly used 2D navigator gated techniques. The results demonstrate the high performance, reproducibility and reliability of 3D spiral imaging with B2B-RMC when data acquisition is gated to alternate cardiac cycles. Using this technique, a further in-vivo study demonstrates thickening of the coronary vessel wall with age in healthy subjects and these results are shown to be consistent with outward remodelling of the vessel wall. Finally, the performance of B2B-RMC in a variety of coronary vessel wall applications, including in a small cohort of patients with confirmed coronary artery disease, is presented.
The Motivation Conundrum: What motivates university students in an EAP program?

The purpose of the research project described in this paper is to examine the salient features of motivation driving tertiary level learners of English for Academic Purposes (EAP) in the Israeli student population at Bar Ilan University. The quantitative study included 228 undergraduate university EAP students studying in various disciplines. Dornyei’s L2 Motivational Self-System Questionnaire was translated to Hebrew and modified for cultural appropriateness and language clarity. Exploratory factor analysis of the students' answers revealed seven salient features, ranked from highest to lowest, underlying motivation in second language learning with varying degrees of perceived importance. The results present an Israeli perspective which differs from other studies conducted on English Foreign Language (EFL) populations. This leads to the conclusion that a broad perspective toward motivation in the language classroom is important in order to understand motivation among EAP students. Implications for pedagogy and suggestions for future research are explored and discussed.
Physical Models of Human Motion for Estimation and Scene Analysis

Physical Models of Human Motion for Estimation and Scene Analysis Marcus A Brubaker Doctor of Philosophy Graduate Department of Computer Science University of Toronto 2011 This thesis explores the use of physics based human motion models in the context of videobased human motion estimation and scene analysis. Two abstract models of human locomotion are described and used as the basis for video-based estimation. These models demonstrate the power of physics based models to provide meaningful cues for estimation without the use of motion capture data. However promising, the abstract nature of these models limit the range of motion they can faithfully capture. A more detailed model of human motion and ground interaction is also described. This model is used to estimate the ground surface which a subject interacts with, the forces driving the motion and, finally, to smooth corrupted motions from existing trackers in a physically realistic fashion. This thesis suggests that one of the key difficulties in using physical models is the discontinuous nature of contact and collisions. Two different approaches to handling ground contacts are demonstrated, one using explicit detection and collision resolution and the other using a continuous approximation. This difficulty also distinguishes the models used here from others used in other areas which often sidestep the issue of collisions.
Custom Transient Finite Element Method and Ray Tracing Hybridization Strategies for Ultrasonic Testing Modelling

The transient spectral element method (SEM) is a specific high order finite element method that is particularly accurate and fast with a low memory footprint, hence enabling 3D ultrasonic testing simulations on a standard PC. However, particular care in its settings and hybridization with a semi-analytical solution remains a major challenge when seeking for both practicality and performance. A natural hybrid strategy consists of coupling a field calculated by ray tracing in the defect-free object to a SEM subdomain wherein the perturbation is enclosed, then synthesizing the signal with a reciprocity argument. The difficulty is to define the suited coupling strategy when the flaw response interacts with the back wall. In a highly heterogeneous medium, it may even become necessary to widen the numerical domain to the entire thickness of the inspected object and, therefore, to ensure the performance of the SEM through a custom discretization strategy. Here we present different customized uses of the SEM for practical ultrasonic inspection applications and discuss how they complement the ray tracing solution.
SCMA Codebooks Optimization Based on Genetic Algorithm

Sparse code multiple access (SCMA) is a nonorthogonal multiple access scheme based on joint modulation and spread spectrum procedure. This scheme allows to increase the number of active users inside a given time-frequency resource. Design of SCMA codebooks is a challenging problem. The paper considers the design of SCMA codebooks based on Genetic Algorithm (GA). In general case, mother constellation is not required for GA, and optimization is performed directly on the codebooks. We present the obtained structured codebooks containing two antipodal codeword pairs. Optimization was carried out to improve SCMA signal performance in additive white Gaussian noise (AWGN) channel by constraining the average energy of codewords. The obtained codebooks have minimum Euclidean distance equal to 0.87 (at unit average power of SCMA signal) and outperform known codebooks in AWGN channel with both Maximum Likelihood (ML) receiver or Message Passing Algorithm (MPA) detection. The comparison of existing and proposed codebooks is performed using computer simulation and union bounds. The asymptotic gain over the best known codebooks is 0.8 dB. As a result of the simulation, proposed codebooks demonstrate similar performance for ML and MPA detection algorithms. The proposed method is suitable for codebook design for other non-orthogonal schemes, e. g. , Pattern Division Multiple Access (PDMA).