Miracle-dz/UniFAR-FTUs huggingface dataset:
Quantum law for equipartition of energy

One of the fundamental laws of classical statistical physics is the energy equipartition theorem which states that for each degree of freedom the average kinetic energy equals $E_k=k_B T/2$, where $k_B$ is the Boltzmann constant and $T$ is temperature of the system. Despite the fact that quantum mechanics has already been developed for more than 100 years still there is no quantum counterpart of this theorem. We attempt to fill this far-reaching gap and formulate the quantum law for equipartition of energy in the appealing form $E_k = \langle \mathcal E_k \rangle$, where $\mathcal E_k$ is thermal kinetic energy per one degree of freedom of the thermostat consisting of harmonic oscillators and $\langle . \rangle$ denotes averaging over frequencies $\omega$ of those thermostat oscillators which contribute to $E_k$ according to the probability distribution $\mathbb P(\omega)$. We derive it for two paradigmatic and exactly solvable models of quantum open systems: a free Brownian particle and a harmonic oscillator. We formulate conditions for validity of the relation $E_k = \langle \mathcal E_k \rangle$ for other quantum systems.
First steps towards national radon action plan in Serbia

Abstract Radon problem has a special attention in many countries in the world and the most of them have established national radon programmes. The radon issues in Serbia have not been approached in a systematic and organized way. Currently, there are many research groups and institutions working in radon field, and it is a good basis to integrate all these activities into a comprehensive national programme to define the strategic objectives and action plan for the next few years. Also, Serbia as a candidate for membership in the EU is obliged to harmonize its legislation, including the field of radiation protection in which the radon issues has an important role. In this report, a brief history of radon research, present status and plans for the future activity on radon issues in Serbia are presented. Regarding the long-term plans, the establishment and implementation of the Radon Action Plan with the primary goal of raising awareness about the harmful effects of public exposure to radon and implementing a set of measures for its reduction. In that sense, the synergy between the national, regional and local organizations responsible for public health and radiation protection must be achieved.
A comparative study of central corneal thickness, mean keratometry and astigmatism in persons with and without refractive errors in Taif

The anterior corneal surface is the major refractive element of the human eye, contributing about 80% of the dioptric power of the whole eye in the nonaccommodated state. 1,2 The structure of the human cornea has a non-uniform curvature with variable thickness throughout. It is thinner at the centre and thickens towards the edges. The viscous fluid in the anterior chamber of the eye exerts pressure on the cornea that inflates it and gives its shape. 3 Corneal thickness is an important indicator of corneal health, and its alteration may be indicative of different pathologies. 4 Its measurement is the essential factor to assign to the corneal status, endothelial pump mechanism and in wide range of disorders; as ectatic dystrophies, contact lenses related complication, dry eye, and diabetes mellitus. In addition, it is an increasingly important procedure in the evaluation of patients with ocular hypertension or glaucoma. The curvature of the internal and external surfaces significantly affects its refractive power but the influence of the refractive error on corneal thickness has not yet been clearly established. There are ABSTRACT
Toeplitz Matrices in the Problem of Semiscalar Equivalence of Second-Order Polynomial Matrices

We consider the problem of determining whether two polynomial matrices can be transformed to one another by left multiplying with some nonsingular numerical matrix and right multiplying by some invertible polynomial matrix. Thus the equivalence relation arises. This equivalence relation is known as semiscalar equivalence. Large difficulties in this problem arise already for 2-by-2 matrices. In this paper the semiscalar equivalence of polynomial matrices of second order is investigated. In particular, necessary and sufficient conditions are found for two matrices of second order being semiscalarly equivalent. The main result is stated in terms of determinants of Toeplitz matrices.
Renormalizable Gravitational Action That Reduces to General Relativity on the Mass-Shell

We derive the equation that relates gravity to quantum mechanics: R|mass-shell=8πGc4LSM, where R is the scalar curvature, G is the gravitational constant, c is the speed of light and LSM is the Standard Model Lagrangian, or its future replacement. Implications of this equation are discussed in the paper. In particular, we show (in the last section) that this equation is the transformation that relates four-dimensional physics to two-dimensional physics.
Visualization of a nonlinear conducting path in an organic molecular ferroelectric by using emission of terahertz radiation

: A nonlinear electric transport and switching to a negative resistance state is one of typical electric-field-induced phenomena in correlated electron materials, while their mechanisms are generally difficult to solve. In the present study, we apply the terahertz-radiation imaging method to an organic ferroelectric, α -(BEDT-TTF) 2 I 3 [BEDT-TTF: bis(ethylenedithio)tetrathiafulvalene] and investigate the nature of its negative resistance phenomenon. When the negative resistance state is produced, the ferroelectric order is melted in an elongated region with the width of ∼ 100 μ m and that region grows along the direction inclined by about 40 ° from the b axis with the increase of nonlinear current. A comparison of the terahertz radiation intensity with the current magnitude revealed that the melted region forms a conducting path. We interpreted the diagonal growth of the conduction path by taking into account the anisotropy of the intermolecular transfer integrals.
Backward Reduction of CNN Models with Information Flow Analysis

This paper proposes backward reduction, an algorithm that explores the compact CNN design from the information flow perspective. This algorithm can remove substantial non-zero weighting parameters (redundant neural channels) by considering the network dynamic behavior, which the traditional model compaction techniques cannot achieve, to reduce the size of a model. With the aid of our proposed algorithm, we achieve significant model reduction results of ResNet-34 in ImageNet scale (32.3% reduction), which is 3X better than the state-of-the-art result (10.8%). Even for highly optimized models like SqueezeNet and MobileNet, we still achieve additional 10.81% and 37.56% reduction, respectively, with negligible performance degradation.
You Will Be Lucky To Break Even

There is a substantial body of literature on the semantics of English verbal complement constructions starting with Kiparsky and Kiparsky (1970) and Karttunen (1971, 1973), including Rudanko (1989, 2002), Nairn et al. (2006), Egan (2008) and Karttunen (2012). These studies have developed a semantic classification of verbs and verb-noun collocations that take clausal complements. They focus on constructions that give rise to implied commitments that the author cannot disavow without being incoherent or without contradicting herself. For example, (1a) presupposes that Kim had not rescheduled the meeting, (1b) entails that she did not and presupposes that she intended to reschedule it.
Local Generalized Morrey Spaces and Singular Integrals with Rough Kernel

Let 2 Ls(Sn􀀀1) with s > 1 be homogeneous of degree zero and hasmean value zero on Sn􀀀1. In this paper, we will study the boundedness ofhomogeneous singular integrals with rough kernel on the local generalizedMorrey spaces LMfx0gp;' for s0 p or p < s. We will also prove that thecommutator operators formed by a local BMO function b and these roughoperators are bounded on the local generalized Morrey spaces LMfx0gp;' .
A dual circularly polarized slot‐fed horn array antenna with linear polarization‐tracking feature

An original architecture to generate two orthogonal circular polarizations with slotted waveguide arrays is presented in this communication. The proposed solution consists of two interleaved slotted ridge waveguide arrays sharing the same aperture and feeding a common polarizing layer represented by a dual circular polarization horn array. The radiating element realizing the linear‐to‐circular polarization conversion is made of a slot‐fed compact septum polarizer flaring into a pyramidal horn. The horn‐loaded slot model is extracted, thus allowing the synthesis of large arrays. A dual circular polarization slot‐fed horn array antenna is designed for Ku‐band operation. The two polarizations, when combined with proper phase relation, enable the tracking of two orthogonal linear polarizations. The antenna exhibits remarkable performance for both circular and linear polarization operating modes.
Midinfrared one-dimensional photonic crystal constructed from two-dimensional electride material

Dicalcium nitride (Ca 2 N) is a layered material that has been recently identified as a two-dimensional electride, based on first-principles calculations, where the electronic property and the optical complex dielectric function are studied using density functional theory. We find that the optical permittivity tensor is highly anisotropic, and Ca 2 N possesses metallic characters when the in-plane dielectric function is negative in midinfrared frequency. In addition, the enhanced midinfrared transmission property and the field distribution of one-dimensional photonic crystals composed of alternating Ca 2 N layers and the dielectric material are theoretically studied using the transfer-matrix method. It is found that the Ca 2 N photonic crystals support a series of passbands and stopbands the numbers of which increase with the thickness and the permittivity of the dielectrics. The field distributions show that the transmission resonances in the passband are attributed to the coupled Fabry-Perot resonances of the individual reactively loaded dielectric slabs. It is also noticed that these resonances lie within certain characteristic frequency bands which are independent of the period of the photonic crystal. The low-frequency edge of the passband is highly tunable by the thickness of the electride material and the dielectric material, the permittivity of the dielectric layer, while the high-frequency edge is insensitive to the electride material thickness. Moreover, the first band gap in lower frequency is almost omnidirectional and polarization insensitive. When defect layers are introduced, the twin defect modes are found, and the frequency and the frequency interval of the two defect modes can be tuned just by changing the permittivity, the thickness and the position of the defect layer, respectively. Polarization and angular insensitive absorption bands can also be obtained for the electride-dielectric photonic crystal with a reflective substrate. These properties of electride material photonic crystals have potential applications in tunable multiband filters and absorbers in the midinfrared region.
Investigation of the performance of strain-engineered silicon nanowire field effect transistors (ɛ-Si-NWFET) on IOS substrates

In the current work, a design space for developing the performance enhanced strain-engineered Si nanowire field-effect-transistors has been provided. The fraction of insertion of the nanowire channel into the Insulator-on-Silicon substrate with judicious selection of high-k gate insulators is used as the key design parameter. The combined effect of fractional insertion and gate insulators results in inducing stress into the nanowire channel and, depending on their selection, it changes from tensile to compressive. Such induced-stress alters the existing inherent phononic-stress, leading to the modification of the carrier transport in the device channel. The carrier transport behavior in such partially embedded nanowire FETs has been modeled by incorporating the relevant stress-related effects into the indigenously developed self-consistent quantum-electrostatic framework. These equations are solved by employing the non-equilibrium Green's function formalism. The study shows the phonon scattering under tensile strain to occur at the expense of electron energy; however, the electrons can also gain energy during such scattering in compressive stress. Thus, the device current has been observed to increase with tensile stress and it achieves relatively smaller values when the inherent tensile phononic stress is balanced by the induced compressive stress. However, the current is finally observed to increase once the compressive stress overcomes the inherent tensile phononic stress. In general, the present devices exhibit promising Ion/Ioff ratio for all of the fractional insertions and gate dielectrics with a maximum Ioff of <10 nA/μm, threshold voltage of sub-0.3 V, gm of ∼104 µS/µm, sub-threshold swing of ∼100 mV/dec, and drain-induced-barrier-lowering of ∼100 mV/V.In the current work, a design space for developing the performance enhanced strain-engineered Si nanowire field-effect-transistors has been provided. The fraction of insertion of the nanowire channel into the Insulator-on-Silicon substrate with judicious selection of high-k gate insulators is used as the key design parameter. The combined effect of fractional insertion and gate insulators results in inducing stress into the nanowire channel and, depending on their selection, it changes from tensile to compressive. Such induced-stress alters the existing inherent phononic-stress, leading to the modification of the carrier transport in the device channel. The carrier transport behavior in such partially embedded nanowire FETs has been modeled by incorporating the relevant stress-related effects into the indigenously developed self-consistent quantum-electrostatic framework. These equations are solved by employing the non-equilibrium Green's function formalism. The study shows the phonon scattering under ten.
On Plasmonic Superradiance, the Scaling Laws of Spontaneous Parametric Downconversion, and the Principles and Recent Advances in Nonlinear Optics

This thesis covers three different topics. The first part is a pedagogical review of the basic principles and recent advances in nonlinear optics. It was originally written as a chapter for the proceedings of the “International School of Physics (Enrico Fermi)” summer school on Photonics held in June, 2014. It is included to provide some background information about nonlinear optical processes in general, and is particularly relevant for the third part of this thesis which is based on the second-order nonlinear optical process of spontaneous parametric downconversion. The second part is based on original research, and deals with superradiance in plasmonic nanostructures. The process of superradiance, as introduced by Dicke in 1954, entails the shortening of the spontaneous emission lifetime of a collection of N quantum emitters as a consequence of the development of a macroscopic dipole moment. Specifically, the lifetime is shortened by a factor of 1/N , and the linewidth is broadened by a factor of N . Such a linewidth dependence has been previously observed in systems of several plasmonic ‘emitters’. However, a clear physical insight into this phenomenon and how it relates to Dicke superradiance has not been shown yet. In this part, we demonstrate by experiment, simulation, and a simple analytical model that Dicke’s superradiance can indeed be observed in a planar array of plasmonic nanoantennas, with a linewidth that scales linearly with the number of nanoantennas within a square wavelength. The third part is also based on original research, and is based on the scaling laws of spontaneous parametric downconversion (SPDC) for a type-I phasematching configuration. The variation of bi-photon generation rate, heralding efficiency and radiance with parameters such as crystal length, pump focussing and collection waist sizes are examined for collinear and non-collinear emission. The results can be used to maximize the brightness of the SPDC source or increase the heralding efficiency depending on the application.
Linked and fully coupled 3D earthquake dynamic rupture and tsunami modeling for the Húsavík–Flatey Fault Zone in North Iceland

Abstract. Tsunamigenic earthquakes pose considerable risks, both economically and socially, yet earthquake and tsunami hazard assessments are typically conducted separately. Earthquakes associated with unexpected tsunamis, such as the 2018 Mw 7.5 strike-slip Sulawesi earthquake, emphasize the need to study the tsunami potential of active submarine faults in different tectonic settings. Here, we investigate physics-based scenarios combining simulations of 3D earthquake dynamic rupture and seismic wave propagation with tsunami generation and propagation. We present time-dependent modeling of one-way linked and 3D fully coupled earthquakes and tsunamis for the ∼ 100 km long Húsavík–Flatey Fault Zone (HFFZ) in North Iceland. Our analysis shows that the HFFZ has the potential to generate sizable tsunamis. The six dynamic rupture models sourcing our tsunami scenarios vary regarding hypocenter location, spatiotemporal evolution, fault slip, and fault structure complexity but coincide with historical earthquake magnitudes. Earthquake dynamic rupture scenarios on a less segmented fault system, particularly with a hypocenter location in the eastern part of the fault system, have a larger potential for local tsunami generation. Here, dynamically evolving large shallow fault slip (∼ 8 m), near-surface rake rotation (± 20∘), and significant coseismic vertical displacements of the local bathymetry (± 1 m) facilitate strike-slip faulting tsunami generation. We model tsunami crest to trough differences (total wave heights) of up to ∼ 0.9 m near the town Ólafsfjörður. In contrast, none of our scenarios endanger the town of Akureyri, which is shielded by multiple reflections within the narrow Eyjafjörður bay and by Hrísey island. We compare the modeled one-way linked tsunami waveforms with simulation results using a 3D fully coupled approach. We find good agreement in the tsunami arrival times and location of maximum tsunami heights. While seismic waves result in transient motions of the sea surface and affect the ocean response, they do not appear to contribute to tsunami generation. However, complex source effects arise in the fully coupled simulations, such as tsunami dispersion effects and the complex superposition of seismic and acoustic waves within the shallow continental shelf of North Iceland. We find that the vertical velocity amplitudes of near-source acoustic waves are unexpectedly high – larger than those corresponding to the actual tsunami – which may serve as a rapid indicator of surface dynamic rupture. Our results have important implications for understanding the tsunamigenic potential of strike-slip fault systems worldwide and the coseismic acoustic wave excitation during tsunami generation and may help to inform future tsunami early warning systems.
Axicon aberration leading to short-range nondiverging optical array and elliptical dark hollow beam

Abstract. We propose a unique method for producing nondiverging optical array and elliptical hollow beam in a controlled manner using aberration patterns generated from oblique illumination of axicon. The optical arrays with propagation invariance property are persisted for short ranges in the focal depth, whereas diverging array with a constant number of bright spots is produced beyond bottle beam. The measured variation in the geometrical parameters of obliquely illuminated axicon setup has facilitated precise control on the dimension of optical array and shape of the elliptical hollow beam, respectively. The theoretical analysis confirms the experimental results for the generation of short-range nondiverging optical array and elliptical dark hollow beam with fine control. To the best of our knowledge, this is the first experimental approach to extend the potential of axicon beyond generation of Bessel and circular hollow beams.
A frica’s Recent Growth Performance and Development Challenges 1

For most of the period up to the mid1990s, Africa’s growth performance was unimpressive, attracting characterizations as “a growth tragedy over the past three decades” (UNU/AERC 1998:10), and “a continent of missed growth opportunities” (UNCTAD 1998:115). Although, overall, economic growth rate improved slightly from the late 1990s into the early 21st century, average per capita GDP growth was still negative, at -0.5 per cent over the 1991–2000 period. The average economic growth rate over the 1993–2003 period was only 2.8 per cent. Generally, Africa’s economic growth performance in the 2000s marked a significant improvement over the 1990s decade. Table 1 shows the overall real GDP growth rates.
First Results on the Rare Decay K+ → π+νν from the NA62 Experiment at CERN

The NA62 experiment at CERN Super Proton Synchrotron (SPS) is currently taking data to measure the ultra-rare decay K + → π + ν ν ¯ . This decay, whose Branching Ratio (BR) is predicted with high precision within the Standard Model (SM), is one of the best candidates to reveal the indirect effects of New Physics (NP) at the highest mass scales. The NA62 experiment is designed to measure BR ( K + → π + ν ν ¯ ) with a decay-in-flight technique, novel for this channel. NA62 took data in 2016, 2017 and 2018; statistics collected in 2016 allows NA62 to reach the SM sensitivity for this decay, reaching the single event sensitivity (SES) and showing the proof of principle of the experiment. The preliminary result on BR ( K + → π + ν ν ¯ ) from the analysis of the 2016 data set is described.
Students’ Covariational Reasoning in Solving Integrals’ Problems

Covariational reasoning plays an important role to indicate quantities vary in learning calculus. This study investigates students’ covariational reasoning during their studies concerning two covarying quantities in integral problem. Six undergraduate students were chosen to solve problems that involved interpreting and representing how quantities change in tandem. Interviews were conducted to reveal the students’ reasoning while solving covariational problems. The result emphasizes that undergraduate students were able to construct the relation of dependent variables that changes in tandem with the independent variable. However, students faced difficulty in forming images of continuously changing rates and could not accurately apply the concept of integrals. These findings suggest that learning calculus should be increased emphasis on coordinating images of two quantities changing in tandem about instantaneously rate of change and to promote conceptual knowledge in integral techniques.
Introduction to gestural similarity in music. An application of category theory to the orchestra

Mathematics, and more generally computational sciences, intervene in several aspects of music. Mathematics describes the acoustics of the sounds giving formal tools to physics, and the matter of music itself in terms of compositional structures and strategies. Mathematics can also be applied to the entire making of music, from the score to the performance, connecting compositional structures to the acoustical reality of sounds. Moreover, the precise concept of gesture has a decisive role in understanding musical performance. In this article, we apply some concepts of category theory to compare gestures of orchestral musicians, and to investigate the relationship between orchestra and conductor, as well as between listeners and conductor/orchestra. To this aim, we will introduce the concept of gestural similarity. The mathematical tools used can be applied to gesture classification, and to interdisciplinary comparisons between music and the visual arts.