Miracle-dz/UniFAR-FTUs huggingface dataset:
Dinamika Pembelajaran Masa Pandemi Covid-19: Kekhawatiran Learning Loss Pada Siswa

Dinamika pembelajaran yang dialami siswa selama pandemi Covid-19 memunculkan kekhawatiran akan terjadinya fenomena learning loss. Learning loss adalah sebuah kondisi hilangnya sebagian kecil atau sebagian besar pengetahuan dan keterampilan dalam perkembangan akademis yang biasanya diakibatkan oleh terhentinya proses pembelajaran dalam dunia pendidikan. Melalui studi kepustakaan, penelitian ini akan memberikan pemaparan mengenai konsep learning loss, yang mana fenomema learning loss cukup hangat dikaitkan dengan kondisi pembelajaran masa pandemi covid-19 sekarang ini. Penelitian ini merupakan penelitian kepustakaan dengan prosedur (1) memilih topik, (2) mengeksplorasi informasi dari topik terpilih, (3) menentukan fokus penelitian dari hasil eksplorasi informasi,(4) membaca sumber-sumber yang relevan dengan fokus penelitian, (5) membuat dan (6) mengolah catatan penelitian, serta (7) menyusun laporan dalam bentuk artikel penelitian. Data penelitian diperoleh dengan memanfaatkan sumber data sekunder seperti buku, artikel ilmiah, dan website. Pengumpulan data menggunakan teknik dokumentasi dengan memanfaatkan diri peneliti sebagai instrumen penelitian. Data dianalisis melalui metode analisis konten. Dari penelitian diperoleh hasil bahwa learning loss yang terjadi pada siswa sesungguhnya tidak semata diakibatkan oleh situasi pandemi, namun akibat tidak efektifnya pembelajaran secara umum. Tidak efektifnya pembelajaran sudah terjadi di masa sebelum pandemi. Hanya saja hadirnya pandemi dianggap akan semakin memperparah kejadian learning loss pada siswa.
Coherent Structure in a Turbulent Axisymmetric Jet via a Vector Implementation of the Proper Orthogonal Decomposition

by Muhammad Owais Iqbal The coherent structure in the near-field of an axisymmetric turbulent jet at a Reynolds number of 3.8×10 and Mach number of 0.3 is experimentally characterized by a vector implementation of the proper orthogonal decomposition (POD). The POD eigenfunctions and associated eigenvalues are extracted at several selected streamwise locations in the initial region. The focus on the near-field is motivated by its importance in numerous technical applications. Results show a rapid energy convergence with POD mode number. Examination of the relative energy contained in the combined azimuthal and radial components of the POD modes reveals that it is comparable to that in the streamwise component. The streamwise evolution of the eigenvalue spectra is characterized by a remarkable variation in the azimuthal mode number energy distribution leading to the dominance of azimuthal mode m = 1 beyond the end of the jet core. In contrast, a scalar implementation using only the streamwise component shows the dominance of mode m = 2 which is consistent with previous scalar implementations of the POD. For a given azimuthal mode number, the eigenvalue spectra exhibit a broad spectral peak which occurs at a constant value of Strouhal number based on local Muhammad Owais Iqbal shear layer momentum thickness and jet velocity. The phase information required for a local reconstruction of the jet structure is obtained by projecting the POD eigenmodes onto instantaneous realizations of the flow at fixed streamwise locations. The instantaneous realizations are obtained by utilizing cross-stream arrays of multi-sensor probes in conjunction with linear stochastic estimation (LSE). Results clearly show the local dynamic behavior of each component of the jet structure.
Scattering by a right-angled lossy dielectric wedge

Electromagnetic scattering by a right-angled lossy dielectric wedge at normal incidence is considered in detail. The lossy dielectric material of the wedge is simulated using second-order impedance boundary conditions on its faces. The Maliuzhinets method is employed to obtain the total exterior field. A high-frequency asymptotic approximation of the Sommerfeld integral is carried out to obtain a UTD expression for the total field. The predictions are validated against experimental measurements taken in a controlled laboratory environment. A comparison with the widely used heuristic UTD diffraction coefficient of Luebbers is presented and the validity of the latter coefficient is discussed.
A developing realist model of the pedagogical affordances of ICTs

This article sets out the eWits model of the pedagogical affordances of ICTs. These are inherent properties of computer technology that constitute possibilities for teachers to act to enable learning in classroom contexts. The model is informed by Gibson’s realist theory of the psychological affordances of objects. We challenge interpretivist notions of affordance: while teachers recognise ICT affordances and activate them in pedagogical practices, these acts of recognition do not constitute them. Affordances are powers and potentials in the technology, and exist whether or not they are recognised and actualised by a teacher. On this understanding, we put forward a typology of ICT affordances that can be read in contrasting directions. First, it models a hierarchy of technological potentials, sourced initially in the capability of tools themselves, which afford a succession of action possibilities for teachers, from technological literacy, to the representation and recontextualisation of knowledge, to pedagogical engagement with learners. Second, it reveals how recognition of these affordances by teachers is manifest in pedagogical decision-making in the ongoing knowledge construction that characterises classroom activities. Our consolidation of the model is described, as we have developed it in the course of our own research work.
Mixing Augmentation of Transverse Injection in Scramjet Combustor

A method for augmenting the mixing of transverse injection in a scramjet combustor is suggested, and its effectiveness is checked by numerical methods. The intent was to promote streamwise vorticity by modifying the injector geometry using a cavity to increase the mixing rate and penetration. A three-dimensional Navier ‐ Stokes code adopting the upwind method of Edwards’ s low diffusion e ux splitting scheme was used. The k‐! SST turbulence model was used to calculate the turbulent viscosity. The injector models proposed showed remarkable increases of streamwise vorticity and, as a result, signie cant improvements in mixing characteristics such as mixing rate and penetration. However, the proposed models also showed additional losses of stagnation pressure. Themixing characteristicsarestrongly related to the jet-to-cross e ow momentum e ux ratio J. In the case of higher values of J, slower mixing rates, higher penetration, and more losses of stagnation pressure are shown.
On the input-output stability of time-varying nonlinear feedback systems--Part II: Conditions involving circles in the frequency plane and sector nonlinearities

The object of this paper is to outline a stability theory based on functional methods. Part I of the paper was devoted to a general feedback configuration. Part II is devoted to a feedback system consisting of two elements, one of which is linear time-invariant, and the other nonlinear. An attempt is made to unify several stability conditions, including Popov's condition, into a single principle. This principle is based on the concepts of conicity and positivity, and provides a link with the notions of gain and phase shift of the linear theory. Part II draws on the (generalized) notion of a "sector non-linearity. " A nonlinearity N is said to be INSIDE THE SECTOR {\alpha,\beta} if it satisfies an inequality of the type \langle(Nx-\alphax)_{t}, (Nx-\betax)_{t}\rangle\leq0 . If N is memoryless and is characterized by a graph in the plane, then this simply means that the graph lies inside a sector of the plane. However, the preceding definition extends the concept to include nonlinearities with memory. There are two main results. The first result, the CIRCLE THEOREM, asserts in part that: If the nonlinearity is inside a sector {\alpha, \beta} , and if the frequency response of the linear element avoids a "critical region" in the complex plane, then the closed loop is bounded; if \alpha > 0 then the critical region is a disk whose center is halfway between the points -1/\alpha and -1/\beta , and whose diameter is greater than the distance between these points. The second result is a method for taking into account the detailed properties of the nonlinearity to get improved stability conditions. This method involves the removal of a "multiplier" from the linear element. The frequency response of the linear element is modified by the removal, and, in effect, the size of the critical region is reduced. Several conditions, including Popov's condition, are derived by this method, under various restrictions on the nonlinearity N ; the following cases are treated: (i) N is instantaneously inside a sector {\alpha, \beta} . (ii) N satisfies (i) and is memoryless and time-invariant. (iii) N satisfies (ii) and has a restricted slope.
Multiple pesticide residue determination in major vegetables purchased from Gazipur district of Bangladesh

The present study was initiated to detect and quantify pesticide residues in three selected major vegetables (hyacinth bean, cauliflower and yard long bean) collected from 5 local markets of Gazipur district of Bangladesh. The vegetable samples were prepared by Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction technique and analyzed by Gas Chromatography (GC) equipped with Flame Thermionic Detector (FTD). In this study, 45 vegetable samples were analyzed. Out of 15 samples of hyacinth bean, 2 samples (13% of the total samples) contained pesticide residues above MRL and the remaining samples did not contain any detectable pesticide residues. In the instance of cauliflower, 2 samples (13% of the total number of samples) contained pesticide residues above MRL, while the remaining samples had no detectable pesticide residues. Pesticide residues with levels exceeding MRL were found and measured in 3 samples (20% of the total number of samples) from 15 yard long bean samples. From remnant samples, no pesticide residue was detected. This study depicts the overall scenario of pesticide contamination in vegetables specially in hyacinth bean, cauliflower and yard long bean available in the local markets of Gazipur city, Bangladesh. As a result, it is important to intensify routine pesticide residue monitoring in commercially cultivated vegetables. Asian Australas. J. Food Saf. Secur. 2022, 6 (2), 57-64
Controversies in spine research: Organ culture versus in vivo models for studies of the intervertebral disc

Intervertebral disc degeneration is a common cause of low back pain, the leading cause of disability worldwide. Appropriate preclinical models for intervertebral disc research are essential to achieving a better understanding of underlying pathophysiology and for the development, evaluation, and translation of more effective treatments. To this end, in vivo animal and ex vivo organ culture models are both widely used by spine researchers; however, the relative strengths and weaknesses of these two approaches are a source of ongoing controversy. In this article, members from the Spine and Preclinical Models Sections of the Orthopedic Research Society, including experts in both basic and translational spine research, present contrasting arguments in support of in vivo animal models versus ex vivo organ culture models for studies of the disc, supported by a comprehensive review of the relevant literature. The objective is to provide a deeper understanding of the respective advantages and limitations of these approaches, and advance the field toward a consensus with respect to appropriate model selection and implementation. We conclude that complementary use of several model types and leveraging the unique advantages of each is likely to result in the highest impact research in most instances.
Coupling-Constant Metamorphosis and Duality between Integrable Hamiltonian Systems

We introduce a noncanonical ("new-time") transformation which exchanges the roles of a coupling constant and the energy in Hamiltonian systems while preserving integrability. In this way we can construct new integrable systems and, for example, explain the observed duality between the H\'enon-Heiles and Holt models. It is shown that the transformation can sometimes connect weak- and full-Painlev\'e Hamiltonians. We also discuss quantum integrability and find the origin of the deformation $\ensuremath{-}\frac{5}{72}{\ensuremath{\hbar}}^{2}{x}^{\ensuremath{-}2}$.
Magnitude and origin of the band gap in NiO

Mesures de photoemission et de spectroscopie isochromat-bremsstrahlung sur un monocristal clive NiO. Comparaison aux predictions de theories de bandes et d'amas. La bande interdite mesuree est importante mais n'est pas seulement determinee par de fortes interactions coulombiennes d-d. NiO n'est donc pas un isolant de Mott-Hubbard au sens le plus simple
Urbach energy dependence of the stability in amorphous silicon thin-film transistors

We investigate the relationship between the stability of amorphous silicon thin-film transistors (a-Si:H TFTs) and the bulk properties of a-Si:H films. Threshold voltage shifts in a-Si:H TFTs are characterized by the thermalization energy Eth for different times and temperatures and fitted by {1+exp[(Eth−Ea)/kT0]}−2. We find that kT0 exhibits a clear correlation to the Urbach energy, but the more significant parameter Ea seems to depend only on the deposition-induced microstructure and not on the Urbach energy, the hydrogen content, or the hydrogen diffusion coefficient.
Comparative Analysis of CRISPR-Cas Systems in Pseudomonas Genomes

Pseudomonas is a bacterial genus with some saprophytic species from land and others associated with opportunistic infections in humans and animals. Factors such as pathogenicity or metabolic aspects have been related to CRISPR-Cas, and in silico studies into it have focused more on the clinical and non-environmental setting. This work aimed to perform an in silico analysis of the CRISPR-Cas systems present in Pseudomonas genomes. It analyzed 275 complete genomic sequences of Pseudomonas taken from the NCBI database. CRISPR loci were obtained from CRISPRdb. The genes associated with CRISPR (cas) and CAS proteins, and the origin and diversity of spacer sequences, were identified and compared by BLAST. The presence of self-targeting sequences, PAMs, and the conservation of DRs were visualized using WebLogo 3.6. The CRISPR-like RNA secondary structure prediction was analyzed using RNAFold and MFold. CRISPR structures were identified in 19.6% of Pseudomonas species. In all, 113 typical CRISPR arrays with 18 putative cas were found, as were 2050 spacers, of which 52% showed homology to bacteriophages, 26% to chromosomes, and 22% to plasmids. No potential self-targeting was detected within the CRISPR array. All the found DRs can form thermodynamically stable secondary RNA structures. The comparison of the CRISPR/Cas system can help understand the environmental adaptability of each evolutionary lineage of clinically and environmentally relevant species, providing data support for bacterial typing, traceability, analysis, and exploration of unconventional CRISPR.
Magnetoresistance of Half-Metallic Oxide Nanocontacts

Magnetoresistive effects (R(0)- R(H))/R(H) exceeding 500% are found at room temperature in a field of 7mT in nanocontacts between Fe{sub 3}O {sub 4} crystallites. The shape of the I(V) curve depends on field and the magnitude of the magnetoresistance is correlated with the resistance, the largest effects occurring when R>100 k{Omega} . The explanation proposed involves hopping transport of spin-polarized electrons through a narrow domain wall pinned at the nanocontact; spin pressure on the domain wall pushes it out into the electrode, leading to the nonlinearity of the I(V) characteristic. Application of current-induced wall motion in a simple fast-switching magnetic memory element is proposed.
DIPOLES, TEMPERATURE GRADIENTS, AND TROPICAL CLIMATE ANOMALIES

Abstract The term “dipole” implies a seesaw, inverse variations of an element at the extremities of an oscillationsystem. The Southern Oscillation and North Atlantic Oscillation are examples of such mainly standing oscillations inpressure. By contrast, for the sea surface temperature (SST) fields in the tropical Atlantic and equatorialIndian Oceans, the SST gradient was found to be closely associated with climatic anomalies, but there is no seesaw. Use the term dipole is misleading.
Sampling Errors in Ensemble Kalman Filtering. Part II: Application to a Barotropic Model

In the current study, the authors are concerned with the comparison of the average performance of stochastic versions of the ensemble Kalman filter with and without covariance inflation, as well as the double ensemble Kalman filter. The theoretical results obtained in Part I of this study are confronted with idealized simulations performed with a perfect barotropic quasigeostrophic model. Results obtained are very consistent with the analytic expressions found in Part I. It is also shown that both the double ensemble Kalman filter and covariance inflation techniques can avoid filter divergence. Nevertheless, covariance inflation gives efficient results in terms of accuracy and reliability for a much lower computational cost than the double ensemble Kalman filter and for smaller ensemble sizes.
Two-Dimensional Navier--Stokes Equations Driven by a Space--Time White Noise

Abstract We study the two-dimensional Navier–Stokes equations with periodic boundary conditions perturbed by a space–time white noise. It is shown that, although the solution is not expected to be smooth, the nonlinear term can be defined without changing the equation. We first construct a stationary martingale solution.Then, we prove that, for almost every initial data with respect to a measure supported by negative spaces, there exists a unique global solution in the strong probabilistic sense.
Multidimensional Inverse Scattering for the Nonlinear Klein-Gordon Equation with a Potential

In this paper, we solve the multidimensional inverse scattering problem for the nonlinear Klein–Gordon equation on Rn,n⩾2:∂2∂t2u(x,t)−Δu(x,t)+u(x,t)+V0(x)u(x,t)+∑j=1∞Vj(x)∣u∣2(j0+j)u(x,t)=0. We prove that the small-amplitude limit of the scattering operator determines uniquely all the Vj,j=0,1,…. Our proof gives, as well, a method for the reconstruction of the Vj,j=0,1,….
The Puzzling Features of the Interstellar Medium in NGC 205

We present CO 1 → 0 and 2 → 1 observations of NGC 205, which is a dwarf elliptical galaxy and a companion to M31. It has long been suggested that NGC 205 has interacted with M31 in the past. The total mass of gas (molecular, atomic, and X-ray emitting) associated with NGC 205 is ~106 M☉, which is 1 order of magnitude less than the mass that should have been returned to its ISM by evolved stars during its lifetime. A burst of star formation began in NGC 205 ~5 × 108 yr ago, ending a few million yr ago; while some of the mass that was returned to the ISM would be used up by the starburst, star formation is a notoriously inefficient process. Moreover, the gas in NGC 205 is rotating, while the stars are not, so any gas returned to the ISM should have zero net angular momentum. We suggest that the angular momentum was added when the preexisting gas interacted with an external gas cloud, either in the disk of M31 or, perhaps less likely, in the region surrounding it. The recent starburst could have been triggered by the interaction, and the blast waves from ensuing supernovae would then have removed most of the remaining gas. Sufficient time has passed since these events for planetary nebulae to have contributed most of the gas we see in this galaxy.
ISOTHERMAL AND MULTITHERMAL ANALYSIS OF CORONAL LOOPS OBSERVED WITH AIA

The coronal filters in the Atmospheric Imaging Assembly (AIA) aboard the Solar Dynamics Observatory peak at different temperatures; the series covers the entire active region temperature range, making AIA ideal for multithermal analysis. Here, we analyze coronal loops from several active regions that have been observed by AIA. We have specifically targeted cool loops (or at least loops with a cool component) that were chosen in the 171 Å channel of AIA, which has a peak response temperature of log T = 5.8. We wanted to determine if the loops could be described as isothermal or multithermal. We find that several of our 12 loops have narrow temperature distributions, which may be consistent with isothermal plasma; these can be modeled with a single flux tube. Other loops have intermediate-width temperature distributions, appear well-constrained, and should be multi-stranded. The remaining loops, however, have unrealistically broad differential emission measures. We find that this problem is the result of missing low-temperature lines in the AIA 131 Å channel. If we repeat the analysis without the 131 Å data, these loops also appear to be well-constrained and multi-stranded.
Bounds testing approaches to the analysis of level relationships

This paper develops a new approach to the problem of testing the existence of a level relationship between a dependent variable and a set of regressors, when it is not known with certainty whether the underlying regressors are trend- or first-difference stationary. The proposed tests are based on standard F- and t-statistics used to test the significance of the lagged levels of the variables in a univariate equilibrium correction mechanism. The asymptotic distributions of these statistics are non-standard under the null hypothesis that there exists no level relationship, irrespective of whether the regressors are I(0) or I(1). Two sets of asymptotic critical values are provided: one when all regressors are purely I(1) and the other if they are all purely I(0). These two sets of critical values provide a band covering all possible classifications of the regressors into purely I(0), purely I(1) or mutually cointegrated. Accordingly, various bounds testing procedures are proposed. It is shown that the proposed tests are consistent, and their asymptotic distribution under the null and suitably defined local alternatives are derived. The empirical relevance of the bounds procedures is demonstrated by a re-examination of the earnings equation included in the UK Treasury macroeconometric model. Copyright © 2001 John Wiley & Sons, Ltd.
Comparison of three-level cluster randomized trials using quantile dispersion graphs

The purpose of this article is to evaluate and compare several three-level cluster randomized designs on the basis of their power functions. The power function of cluster designs depends on the intracluster correlations (ICCs), which are generally unknown at the planning stage. Thus, to compare these designs a prior knowledge of the ICCs is required. Three interval estimation methods are proposed for assigning joint confidence intervals to the two ICCs (corresponding to each cluster level). A detailed simulation study comparing the confidence intervals attained by the different techniques is given. The technique of quantile dispersion graphs is used for comparing the three-level cluster designs. For a given design, quantiles of the power function, are obtained for various effect sizes. These quantiles are functions of the unknown ICC coefficients. To address the dependence of the quantiles on the correlations, a confidence region is computed, and used as a parameter space. A three-level nested data set collected by the University of Michigan to study various school reforms on the achievements of students is used to illustrate the proposed methodology.
Wave packets in dispersive media: an approximation encompassing both main signal and precursors

The propagation of a linear wave packet in a generally dispersive, but non- absorbing, medium is considered. By an extension of the principle of stationary phase to higher inverse order in time, an approximation is derived that encompasses both the main signal propagating at the group speed, and the precursors that precede and follow it.