Miracle-dz/UniFAR-FTUs huggingface dataset:
Rainfall in relation to the jet stream

A study is made of the rainfall occurring at four British stations on occasions when they lie beneath the jet stream. The mean distribution of rainfall in relation to the jet stream provides evidence, in agreement with dynamical theory, for a direct circulation at the jet entrance and an indirect circulation at the jet exit. Precipitation patterns found for uniform currents provide no satisfactory evidence with regard to the preferred vertical circulations within the central region of the jet stream.
On the Modeling of Leg Constraints in the Dynamic Analysis of Gough/Stewart-Type Platforms

This paper investigates the dynamic model of Gough/Stewart-type platforms, focusing on aspects concerning the proper modeling of leg constraints that seem to have been overlooked in a nonnegligible part of the available literature related to the subject. It shows, in particular, how failure in correctly modeling the arrangement of the universal joints connecting the legs to the base may cause positional, kinematic, and dynamic miscalculations. The effects of these errors are investigated and assessed for relevant cases of leg geometries. Numerical simulations are provided to validate the theory.
Scalar problems in junctions of rods and a plate. II. Self-adjoint extensions and simulation models

In this work we deal with a scalar spectral mixed boundary value problem in a spacial junction of thin rods and a plate. Constructing asymptotics of the eigenvalues, we employ two equipollent asymptotic models posed on the skeleton of the junction, that is, a hybrid domain. We, first, use the technique of self-adjoint extensions and, second, we impose algebraic conditions at the junction points in order to compile a problem in a function space with detached asymptotics. The latter problem is involved into a symmetric generalized Green formula and, therefore, admits the variational formulation. In comparison with a primordial asymptotic procedure, these two models provide much better proximity of the spectra of the problems in the spacial junction and in its skeleton. However, they exhibit the negative spectrum of finite multiplicity and for these "parasitic" eigenvalues we derive asymptotic formulas to demonstrate that they do not belong to the service area of the developed asymptotic models.
On vanishing and localizing of transmission eigenfunctions near singular points: a numerical study

This paper is concerned with the intrinsic geometric structure of interior transmission eigenfunctions arising in wave scattering theory. We numerically show that the aforementioned geometric structure can be very delicate and intriguing. The major findings can be roughly summarized as follows. We say that a point on the boundary of the inhomogeneity is singular if the surface tangent is discontinuous there. The interior transmission eigenfunction then vanishes near a singular point where the interior angle is less than π, whereas the interior transmission eigenfunction localizes near a singular point if its interior angle is bigger than π. Furthermore, we show that the vanishing and blowup orders are inversely proportional to the interior angle of the singular point: the sharper the corner, the higher the convergence order. Our results are first of its type in the spectral theory for transmission eigenvalue problems, and the existing studies in the literature concentrate more on the intrinsic properties of the transmission eigenvalues instead of the transmission eigenfunctions. Due to the finiteness of computing resources, our study is by no means exclusive and complete. We consider our study only in a certain geometric setup including corner, curved corner and edge singularities. Nevertheless, we believe that similar results hold for more general singularities and rigorous theoretical justifications are much desirable. Our study enriches the spectral theory for transmission eigenvalue problems. We also discuss its implication to inverse scattering theory.
A Study on the Effectiveness of the Online Platform in Tertiary Education in a Malaysian University

In many facets of our lives, the internet has become indispensable. The internet's role in transforming education has significantly altered both teaching and learning. The ability to learn online has been made feasible by the internet. Nguyen (2015) asserted that this had piqued the curiosity of many researchers and educators who want to use it to strengthen and advance student learning. This small-scale quantitative study examined how well employing online learning works in tertiary education at a Malaysian university. A total of 20 undergraduates from various faculties took part in an online survey. The survey covered both the benefits and drawbacks of online learning. 75% of the undergraduates agreed that using online resources allowed them to take control of their own learning. The results also reveal that, despite having the opportunity to learn conveniently and flexibly through the online platform, undergraduates still consider face-to-face classes a better approach to pursuing their degrees. Using the research findings as a guide, the researchers recommend that instructors using online learning take into account the relevance of the content and solutions, student support, and interaction between students and teachers for effective learning.
Operation mechanism of Schottky barrier nonvolatile memory with high conductivity InGaZnO active layer

Influence of Schottky contact between source/drain electrodes and high conductivity a-InGaZnO active layer to the performance of nonvolatile memory devices was first proposed. The Schottky barrier devices faced to the difficulty on electrical discharging process due to the energy barrier forming at the interface, which can be resolved by using Ohmic devices. A memory window of 2.83 V at programming/erasing voltage of ±13 V for Ohmic and 5.58 V at programming voltage of 13 V and light assisted erasing at −7 V for Schottky devices was obtained. Both memory devices using SiO2/SiOx/SiOxNy stacks showed a retention exceeding 70% of trapped charges 10 yr with operation voltages of ±13 V at an only programming duration of 1 ms.
Analysis of spherical circular microstrip antennas

A comprehensive analysis of spherical circular microstrip patch antennas is presented. The dielectric thickness is considered to be thin. Computation of the wall admittance is also presented. The input impedance is computed using the generalised transmission line model. The values of the input impedance and the resonance frequency are found to be comparable with that of a planar structure when the sphere radius is large. The radiation patterns are computed numerically using the method of moments. The effect of different parameters on the antenna characteristics is investigated.
Strong-field phenomena driven by mid-infrared ultrafast sources

The development of ultrafast and intense laser sources has paved the way to the study of laser–matter interaction in the strong-field regime, where the amplitude of the laser field becomes comparable to the Coulomb field seen by electrons in the proximity of their parent ion. This realm embraces numerous phenomena, such as high-order harmonic generation, tunnel photoionization, laser-induced electron diffraction and holography, ponderomotive electron streaking, and so forth. For a long time, the Ti:Sapphire laser has been the sole workhorse of strong-field scientists; the recent development of intense and tunable ultrafast sources operating in the mid-infrared added an extra dimension to strong-field investigations, with valuable benefits in the understanding of several phenomena and in the development of high-photon-energy coherent sources. In this work we review the recent achievements in strong-field science which were allowed by the exploitation of mid-infrared ultrafast lasers.
Current status of post-traumatic brain injury rehabilitation care in LMI Southeast Asian Countries: A mini systematic review

Low-to-middle income countries (LMICs) in Southeast Asia (SEA) had the highest global traumatic brain injury (TBI). However, post-TBI rehabilitation care may be limited in these countries, thereby contributing to the poorer quality of life (QoL) of patients with TBI. The present systematic review aimed to elucidate the current status of post-TBI rehabilitation care in the LMICs in the SEA region and to discuss the limitations that may hinder the advancement of TBI rehabilitation within this region. A literature search was carried out using five databases (PubMed, Ovid MEDLINE, EMBASE, CINAHL and Scopus), and the final number of articles were selected according to the PRISMA guidelines. This review selected four relevant research articles from Malaysia and Thailand for critical appraisal. These articles showed that the status of post-TBI rehabilitation care in these regions remains unclear based on the scarcity of available literature. Only early rehabilitation care strategies have been discussed in the literature, such as individualised structured cognitive rehabilitation, utilisation of humanoid robots and the implementation of sensory stimulation programs. This review also suggested that TBI rehabilitation improvements may be hindered by a lack of government funding, unequal distribution of care services and reliance on traditional care. Thus, more research into TBI rehabilitation care is significantly needed within the SEA region to overcome these barriers, leading to the preservation of patients’ QoL.
Bandwidth-Enhanced Doherty Power Amplifier With Optimized Quasi-Resistive Power-Combing Load Impedance

This article presents systematic research on the methodology for a wideband post-matching Doherty power amplifier (PM-DPA). First, closed-form derivations are presented to analyze the numerical solutions of the PM-DPA’s output matching network (OMN). In the presented derivations, the passive and reciprocal characteristics of the OMN are incorporated to ensure the physical feasibility of the OMN solutions, and the degree of freedom in choosing the power-combining load impedance (<inline-formula> <tex-math notation="LaTeX">$Z_{\mathrm {L.CO}}$ </tex-math></inline-formula>) is preserved to attain the mathematical completeness of the OMN solutions. The theoretical derivations prove the flexibility of <inline-formula> <tex-math notation="LaTeX">$Z_{\mathrm {L.CO}}$ </tex-math></inline-formula> in the PM-DPA for the first time. Then, the compensated semi-lumped (CSL)-<inline-formula> <tex-math notation="LaTeX">$\lambda $ </tex-math></inline-formula>/4 transmission line (TL) with absorbed transistor parasitics is proposed to take full advantage of the flexibility of <inline-formula> <tex-math notation="LaTeX">$Z_{\mathrm {L.CO}}$ </tex-math></inline-formula> in wideband PM-DPA implementation. The method of tuning <inline-formula> <tex-math notation="LaTeX">$Z_{\mathrm {L.CO}}$ </tex-math></inline-formula> with the help of CSL-<inline-formula> <tex-math notation="LaTeX">$\lambda $ </tex-math></inline-formula>/4 TL for enlarged PM-DPA bandwidth is presented. At last, prototype design of a wideband PM-DPA with optimized quasi-resistive <inline-formula> <tex-math notation="LaTeX">$Z_{\mathrm {L.CO}}$ </tex-math></inline-formula> is presented to verify the effectiveness of the proposed methodology. Measurement results show that the fabricated PM-DPA achieves the state-of-the-art performances, such as the gains of 12–13 dB, the saturated output powers of 43.6–45 dBm, the drain efficiencies of 62%–71% for saturated operation, and drain the efficiencies of 49%–58% for 6-dB power-back-off (PBO) operation over 1.4–2.5 GHz.
Fundamental Factorization of a GLSM Part I: Construction

We define enumerative invariants associated to a hybrid Gauged Linear Sigma Model. We prove that in the relevant special cases these invariants recover both the Gromov–Witten type invariants defined by Chang–Li and Fan–Jarvis–Ruan using cosection localization as well as the FJRW type invariants constructed by Polishchuk–Vaintrob. The invariants are defined by constructing a “fundamental factorization” supported on the moduli space of Landau–Ginzburg maps to a convex hybrid model. This gives the kernel of a Fourier–Mukai transform; the associated map on Hochschild homology defines our theory.
Covariant Bimodules Over Monoidal Hom-Hopf Algebras

Covariant Hom-bimodules are introduced and the structure theory of them in the Hom-setting is studied in a detailed way. The category of bicovariant Hom-bimodules is proved to be a (pre)braided monoidal category and its structure theory is also provided in coordinate form. The notion of Hom-Yetter-Drinfel’d modules is presented and it is shown that the category of Hom-Yetter-Drinfel’d modules is a (pre)braided tensor category as well. As one of the main results, a (pre)braided monoidal equivalence between these tensor categories is veriﬁed, which extends the fundamental theorem of Hom-Hopf modules.
The specialization index of a variety over a discretely valued field

Let $X$ be a proper variety over a henselian discretely valued field. An important obstruction to the existence of a rational point on $X$ is the index, the minimal positive degree of a zero cycle on $X$. This paper introduces a new invariant, the specialization index, which is a closer approximation of the existence of a rational point. We provide an explicit formula for the specialization index in terms of an $snc$-model, and we give examples of curves where the index equals one but the specialization index is different from one, and thus explains the absence of a rational point. Our main result states that the specialization index of a smooth, proper, geometrically connected $\mathbb{C}((t))$-variety with trivial coherent cohomology is equal to one.
From semiclassical Strichartz estimates to uniform $L^p$ resolvent estimates on compact manifolds

We prove uniform $L^p$ resolvent estimates for the stationary damped wave operator. The uniform $L^p$ resolvent estimates for the Laplace operator on a compact smooth Riemannian manifold without boundary were first established by Dos Santos Ferreira-Kenig-Salo and advanced further by Bourgain-Shao-Sogge-Yao. Here we provide an alternative proof relying on the techniques of semiclassical Strichartz estimates. This approach allows us also to handle non-self-adjoint perturbations of the Laplacian and embeds very naturally in the semiclassical spectral analysis framework.
Scalar curvature and an infinite-dimensional hyperkähler reduction

We discuss a natural extension of the K\"ahler reduction of Fujiki and Donaldson, which realises the scalar curvature of K\"ahler metrics as a moment map, to a hyperk\"ahler reduction. Our approach is based on an explicit construction of hyperk\"ahler metrics due to Biquard and Gauduchon. This extension is reminiscent of how one derives Hitchin's equations for harmonic bundles, and yields real and complex moment map equations which deform the constant scalar curvature K\"ahler (cscK) condition. In the special case of complex curves we recover previous results of Donaldson. We focus on the case of complex surfaces. In particular we show the existence of solutions to the moment map equations on a class of ruled surfaces which do not admit cscK metrics.
NP-harsh problems in education

A number of ideas in complexity theory are reviewed and then it is shown that all known classes of complexity of really unmanageable problems have instances in education. These are common problems in the teaching of every branch of science, knowledge and human culture. Selected pedagogic problems classify as NP-harsh problems, i.e. NP-hard problems with bad approximation properties. Some consequences are formulated.
Effectiveness of Microsoft Teams in Student Teachers' Achievement in an EFL Teaching Methods Course

The effectiveness of the Microsoft Teams platform in various subject areas was evident in literature, particularly as much as reflected by students’ and instructors’ perceptions and as rarely as proven by students’ achievement on tests. It also appeared that achievement in EFL teaching methodology courses through assessing Microsoft Teams' effectiveness in students' achievement appeared not to have been addressed. Therefore, this study aimed at assessing the effectiveness of the platform in student teachers' achievement of an EFL Teaching Methods I course offered at the Faculty of Education, Suez Canal University, Egypt, as well as the students’ perceptions of the platform. The study adopted a quasi-experimental approach comprising an experimental group teaching via the platform and another in the traditional face-to-face method. Thirty-two third-year student participants training to be future teachers were involved in the study, forming an equal student number in both groups (n. 16). The study designed and administered an achievement pretest-posttest and a student perception form. Results indicated that the platform was effective in the achievement of the EFL Teaching Methods I course at the experimental group level. It proved even more effective than the traditional method at the experimental-control levels. The participants reported they were generally in favor of the platform. Reasons included the platform utilization of interactive tasks, such as chat rooms, content-sharing, webinars, files, calls, email communication, class notebook, calendars, assignments, and emojis featured by the platform. The study recommends that knowledgeable instructors who are skillful at using the platform capabilities should make a difference in students’ learning reflected by their students’ significant achievement and perceptions.
Vertical Dependency in Sequences of Categorical Random Variables

This paper develops a more general theory of sequences of dependent categorical random variables, extending the works of Korzeniowski (2013) and Traylor (2017) that studied first-kind dependency in sequences of Bernoulli and categorical random variables, respectively. A more natural form of dependency, sequential dependency, is defined and shown to retain the property of identically distributed but dependent elements in the sequence. The cross-covariance of sequentially dependent categorical random variables is proven to decrease exponentially in the dependency coefficient $\delta$ as the distance between the variables in the sequence increases. We then generalize the notion of vertical dependency to describe the relationship between a categorical random variable in a sequence and its predecessors, and define a class of generating functions for such dependency structures. The main result of the paper is that any sequence of dependent categorical random variables generated from a function in the class $\mathscr{C}_{\delta}$ that is dependency continuous yields identically distributed but dependent random variables. Finally, a graphical interpretation is given and several examples from the generalized vertical dependency class are illustrated.
On-diagonal Heat Kernel Lower Bound for Strongly Local Symmetric Dirichlet Forms

This paper studies strongly local symmetric Dirichlet forms on general measure spaces. The underlying space is equipped with the intrinsic metric induced by the Dirichlet form, with respect to which the metric measure space does not necessarily satisfy volume-doubling property. Assuming Nash-type inequality, it is proved in this paper that outside a properly exceptional set, given a pointwise on-diagonal heat kernel upper bound in terms of the volume function, the comparable heat kernel lower bound also holds. The only assumption made on the volume growth rate is that it can be bounded by a continuous function satisfying doubling property, in other words, is not exponential.
Parasitic Parameter Extraction for Calibration Standards Using an Optimization Strategy

This article presents a novel extraction method for parasitic parameters of on-wafer calibration standards using an optimization strategy. Based on the physical models of the calibration standards, the parasitic parameters of all calibration standards can be extracted using the Bayesian optimization method with a fast calculation speed and high accuracy. Compared with the conventional thru-reflect-line (TRL) extraction method, the proposed approach can work well in systems with high crosstalk. The methodology is validated through on-wafer measurements using a ground–signal–ground (GSG) probe with low crosstalk and a ground–signal (GS) probe with high crosstalk. The proposed method shows a comparable accuracy with the TRL method in the low-crosstalk case, while it has higher accuracy in the high-crosstalk scenario.
Model-Based Approach on Multi-Agent Deep Reinforcement Learning With Multiple Clusters for Peer-To-Peer Energy Trading

Peer-to-peer (P2P) energy trading system has the ability to completely revolutionize the current household energy system by sharing energy among residents. As the number of customers employing distributed energy resources (DERs) such as solar rooftops increase, innovation in the double auction market (DA) system is becoming more significant. In this paper, a novel model-based, multi-agent asynchronous advantage actor-centralized-critic with communication (MB-A3C3) approach is carried out. Previous studies are limited since they suffer from unpredictable behavior in renewable energy resources and a large number of prosumers in the peer-to-peer market. As for the model-based strategy, we forecast the trading price and trading quantity in the daily energy trading system in order to overcome unpredictable issues. For the large number of prosumers, the multi-agent and multithreading RL has been chosen as our backbone since the prosumers’ behavior can be diverse; time-series clustering is introduced based on their daily trading behavior. With its environmental model and multi-threaded mechanism, MB-A3C3 is seen to be most efficient in carrying out tasks regards time and precision. The model is conducted on a large scale real-world hourly 2012–2013 dataset of 300 households in Sydney having rooftop solar systems installed in New South Wales (NSW), Australia. Results reveal that the MB-A3C3 approach outperforms other reinforcement learning methods (MADDPG and A3C3), producing lower community energy bills for 300 households. When internal trade (trading among houses) increased and external trade (trading to the grid) decreased, our multiple agent RL (MB-A3C3) significantly lowered energy bills by 17%. In closing the gap between the real-world and theoretical problems, the algorithms herein aid in reducing customers’ electricity bills.
Categorical Logarithmic Hodge Theory, I

We write down a new "logarithmic" quasicoherent category $\operatorname{Qcoh}_{log}(U, X, D)$ attached to a smooth open algebraic variety $U$ with toroidal compactification $X$ and boundary divisor $D$. This is a (large) symmetric monoidal Abelian category, which we argue can be thought of as the categorical substrate for logarithmic Hodge theory of $U$. We show that its Hochschild homology theory coincides with the theory of log-forms on $X$ with logarithmic structure induced by $D$, and in particular, that the noncommutative Hodge-to de Rham sequence on $\operatorname{Qcoh}_{log}(U, X, D)$ recovers known log Hodge structure on the de Rham cohomology of the open variety $U$. As an application, we compute the Hochschild homology of the category of coherent sheaves on the infinite root stack of Talpo and Vistoli in the toroidal setting. We prove a derived invariance result for this theory: namely, that strictly toroidal changes of compactification do not change the derived category of $\operatorname{Qcoh}_{log}(U, X, D)$. The definition is motivated by the coherent object appearing in the author's microlocal mirror symmetry result [20]. In this paper, the first in a series, we work over an algebraically closed field of characteristic zero. The next installment will develop the characteristic p and mixed-characteristic theories.