Miracle-dz/UniFAR-FTUs huggingface dataset:
High thermoelectric performance of solid solutions CuGa1−xInxTe2 (x = 0–1.0)

We synthesized the solid solutions CuGa1−xInxTe2 (x = 0–1.0) by isoelectronic substitution of element In (Ga) for Ga(In) in the CuMTe2 (M = Ga, In) lattices and examined their thermoelectric properties. The structure upon substitution provides much high Seebeck coefficient (α), relatively low thermal (κ), and electrical conductivity (σ). AT 701 K, the α, σ, and κ are 283.15 µV K−1, 1.15 × 104 Ω−1 m−1, and 0.71 W m−1 K−1, respectively, for CuGa0.36In0. 64Te2, which give the figure of merit (ZT) of 0.91, about two times those of the mother compounds CuGaTe2 and CuInTe2. This material holds great application perspectives at intermediate temperatures.
Community Empowerment and Social Welfare Development through Social Entrepreneurship

Social entrepreneurship is an alternative approach to improving social welfare through community empowerment programs. In the Indonesian context, Yayasan Cinta Anak Bangsa (YCAB) and Cinderella Indonesia Foundation (CIF) have essential roles in improving marginalized communities' social welfare. Considering this, it is necessary to conduct a comprehensive study of institutional and leadership dimensions related to the social entrepreneurship approach. This research uses qualitative methods through a case study approach. Data was collected through in-depth interviews with key informants, namely the initiators or founders of YCAB and CIF. Document studies were conducted to understand the organizational profiles. Furthermore, the processing of research data uses triangulation techniques to obtain credible and valid information so that it can be used to reconstruct research thinking ideas related to community and social development from an institutional and leadership perspective in the field of social entrepreneurship. These research findings indicate that Yayasan Cinta Anak Bangsa (YCAB) and Cinderella from Indonesia Center have established partnerships with various parties for collaborative advantages. Thus, Social enterprise plays a vital role in community development and mobilizes the capabilities to maintain livelihoods and improve social welfare.
A uniformly stable conformal FDTD‐method in Cartesian grids

A conformal finite‐difference time‐domain algorithm for the solution of electrodynamic problems in general perfectly conducting 3D geometries is presented. Unlike previous conformal approaches it has the second‐order convergence without the need to reduce the maximal stable time step of conventional staircase approach. A novel proof for the local error rate for general geometries is given, and the method is verified and compared to other approaches by means of several numerical 2D examples. Copyright © 2003 John Wiley & Sons, Ltd.
Rees algebras of edge ideals

Let G be a graph and let I be its edge ideal. We express the presentation ideal of R(I), the Rees algebra of I, in terms of the syzygies of I and the presentation ideal of the special fiber of R(I). A description of the elementary integral vectors of the kernel of the incidence matrix of G is given and then used to study the special fiber of R(I) via Grobner bases.
Estimating technical efficiency with non-neutral shift of the frontier

In the literature, technical efficiency is measured as the ratio of the observed output to potential output. Although there is no a priori theoretical reasoning, in the stochastic framework of measuring technical efficiency, potential output has been conventionally assumed as a neutral shift from observed output, owing solely to a larger intercept term in the frontier production function and without change in the input response coefficients. The objective of this paper is to propose and apply a method to measure technical efficiency without the above assumption. Furthermore, this methodology does not require the restrictive assumption of a particular distribution for the efficiency-related error term, as has been the case until now in the stochastic production function literature. A random sample of farmers from Madurai district in Tamil Nadu, India, was used. The analysis revealed substantial variation in the farm-specific input response coefficients between farms, which means that the contributions of i.
Revised ab initio natural band offsets of all group IV, II-VI, and III-V semiconductors

Using an all-electron band structure approach, we have systematically calculated the natural band offsets between all group IV, III-V, and II-VI semiconductor compounds, taking into account the deformation potential of the core states. This revised approach removes assumptions regarding the reference level volume deformation and offers a more reliable prediction of the "natural" unstrained offsets. Comparison is made to experimental work, where a noticeable improvement is found compared to previous methodologies.
Developing smart city services using intent‐aware recommendation systems: A survey

Smart cities could be defined as urban areas that use Information and Communication Technology (ICT) to solve city problems in efficient and sustainable ways. Intent‐aware Recommender Systems (IARS) within ICT play a crucial role in filtering useless information according to user demands and assist in decision‐making in various smart city platforms. In smart cities, the user traces on IoT, RFIDs, mobiles, and smart sensors capture actual user intent of performing an activity and enhance user satisfaction by proposing optimal services. This paper presents a detailed literature survey of the field of IARS and how it can be used for developing smart city services. First, we present the evolution of IARS with the development of computing technology. Then, we present case studies, synergies, advances, and a reference implementation architecture of IARS for smart cities. We discuss requirements for developing smart city services using IARS. Furthermore, we devise a comprehensive taxonomy of applications and techniques of IARS using different performance parameters. Finally, we elaborate on current issues, challenges, and future research directions in IARS; these directions we believe will pave the way for autonomous service provisioning in smart cities.
Analysis of a rapidly distorted, supersonic, turbulent boundary layer

Rapid distortion concepts are used to calculate the evolution of turbulent stresses in the flow of a compressible boundary layer through a short region of concave curvature. Different models for the rapid part of strain were tested. For all models used, the calculations in the curved region agree well with experimental data. Downstream, however, the discrepancies between experiment and calculation increase, probably because of the increased importance of the mean shear and the nonlinear terms.
Mode expansion and photon operators in dispersive and absorbing dielectrics

Abstract We present a one-dimensional quantization scheme for the electromagnetic field in arbitrary planar absorbing and dispersive dielectrics, taking into account explicitly the finite extent of media. The complete form of the electric field operator includes a part that corresponds to the free fields incident from the vacuum towards the medium and a particular solution which can be expressed by using the classical Green-function integral representation of the electromagnetic field. By expressing the classical Green function in terms of the light modes of the dielectric structure, we obtain a natural generalization to absorbing media of the familiar method of mode expansion which strictly applies to non-absorbing media. As an application of our mode expansion, we obtain general quantum-optical input-output relations relating the output photon operators in vacuum to the input photon operators and to the reservoir noise operators. The input-output relations obtained are uniquely determined by the knowledge of the classical light modes of the planar system. We finally show that our quantization scheme for arbitrary planar dielectrics satisfies the prescribed equal-time commutation relations of QED.
Development of a Low-Cost Smart Sensor GNSS System for Real-Time Positioning and Orientation for Floating Offshore Wind Platform

A low-cost smart sensor GNSS system has been developed to provide accurate real-time position and orientation measurements on a floating offshore wind platform. The approach chosen to offer a viable and reliable solution for this application is based on the use of the well-known advantages of the GNSS system as the main driver for enhancing the accuracy of positioning. For this purpose, the data reported in this work are captured through a GNSS receiver operating over multiple frequency bands (L1, L2, L5) and combining signals from different constellations of navigation satellites (GPS, Galileo, and GLONASS), and they are processed through the precise point positioning (PPP) and real-time kinematic (RTK) techniques. Furthermore, aiming to improve global positioning, the processing unit fuses the results obtained with the data acquired through an inertial measurement unit (IMU), reaching final accuracy of a few centimeters. To validate the system designed and developed in this proposal, three different sets of tests were carried out in a (i) rotary table at the laboratory, (ii) GNSS simulator, and (iii) real conditions in an oceanic buoy at sea. The real-time positioning solution was compared to solutions obtained by post-processing techniques in these three scenarios and similar results were satisfactorily achieved.
THE 'LARGE SIEVE' METHOD AND ITS APPLICATIONS IN THE THEORY OF NUMBERS

CONTENTSNotationIntroduction § 1. The essence of the method. First applications § 2. The probabilistic interpretation of the 'large sieve' § 3. Composite moduli. Application to binary additive problems § 4. The non-vanishing of L-functions near the line σ = 1 § 5. A distribution theorem for the number of classes of primitive quadratic forms with negative determinant § 6. ΣR-equidistribution of prime numbers. Application to A. Selberg' s sieve § 7. The central limit theorem for additive arithmetic functions, given on the set of values of a polynomial for a ΣR-equidistributed sequence § 8. The order of the mean values of multiplicative functions on the set of values of a polynomial for a ΣR-equidistributed sequenceReferences
A multiblock multigrid method for the solution of the three-dimensional Euler equations

A general multiblock, multigrid method for the solution of the Euler equations has been developed. Two types of numerical methods were investigated, van Leer's flux-vector-splitting and Roe's flux-difference-splitting, with MUSCL type differencing used in both methods. An explicit two-step method and a multi-stage Runge-Kutta method have been tested. Results are presented for test cases of a channel flow, nozzle exhaust flow, and a transonic wing.
Scattering mechanisms limiting two-dimensional electron gas mobility in Al0.25Ga0.75N/GaN modulation-doped field-effect transistors

In order to characterize the electron transport properties of the two-dimensional electron gas (2DEG) in AlGaN/GaN modulation-doped field-effect transistors, channel magnetoresistance has been measured in the magnetic field range of 0–12 T, the temperature range of 25–300 K, and gate bias range of +0.5 to −2.0 V. By assuming that the 2DEG provides the dominant contribution to the total conductivity, a one-carrier fitting procedure has been applied to extract the electron mobility and carrier sheet density at each particular value of temperature and gate bias. Consequently, the electron mobility versus 2DEG sheet density has been obtained for each measurement temperature. Theoretical analysis of these results suggests that for 2DEG densities below 7×1012 cm−2, the electron mobility in these devices is limited by interface charge, whereas for densities above this level, electron mobility is dominated by scattering associated with the AlGaN/GaN interface roughness.
Optical cell cleaning with NIR femtosecond laser pulses

Femtosecond laser microscopes have been used as both micro and nanosurgery tools. The optical knock-out of undesired cells in multiplex cell clusters shall be further reported on in this study. Femtosecond laser-induced cell death is beneficial due to the reduced collateral side effects and therefore can be used to selectively destroy target cells within monolayers, as well as within 3D tissues, all the while preserving cells of interest. This is an important characteristic for the application in stem cell research and cancer treatment. Non-precise damage compromises the viability of neighboring cells by inducing side effects such as stress to the cells surrounding the target due to the changes in the microenvironment, resulting from both the laser and laser-exposed cells. In this study, optimum laser parameters for optical cleaning by isolating single cells and cell colonies are exploited through the use of automated software control. Physiological equilibrium and cellular responses to the laser induced damages are also investigated. Cell death dependence on laser focus, determination and selectivity of intensity/dosage, controllable damage and cell recovery mechanisms are discussed.
Modeling light-sound interaction in nanoscale cavities and waveguides

Abstract The interaction of light and sound waves at the micro and nanoscale has attracted considerable interest in recent years. The main reason is that this interaction is responsible for a wide variety of intriguing physical phenomena, ranging from the laser-induced cooling of a micromechanical resonator down to its ground state to the management of the speed of guided light pulses by exciting sound waves. A common feature of all these phenomena is the feasibility to tightly confine photons and phonons of similar wavelengths in a very small volume. Amongst the different structures that enable such confinement, optomechanical or phoxonic crystals, which are periodic structures displaying forbidden frequency band gaps for light and sound waves, have revealed themselves as the most appropriate candidates to host nanoscale structures where the light-sound interaction can be boosted. In this review, we describe the theoretical tools that allow the modeling of the interaction between photons and acoustic phonons in nanoscale structures, namely cavities and waveguides, with special emphasis in phoxonic crystal structures. First, we start by summarizing the different optomechanical or phoxonic crystal structures proposed so far and discuss their main advantages and limitations. Then, we describe the different mechanisms that make light interact with sound, and show how to treat them from a theoretical point of view. We then illustrate the different photon-phonon interaction processes with numerical simulations in realistic phoxonic cavities and waveguides. Finally, we introduce some possible applications which can take enormous benefit from the enhanced interaction between light and sound at the nanoscale.
Nonlinear restrictions on dynamo action. [in magnetic fields of astrophysical objects

Astrophysical dynamos operate in the limit of small magnetic diffusivity. In order for magnetic reconnection to occur, very small magnetic structures must form so that diffusion becomes effective. The formation of small-scale fields is accompanied by the stretching of the field lines and therefore by an amplification of the magnetic field strength. The back reaction of the magnetic field on the motions leads to the eventual saturation of the dynamo process, thus posing a constraint on the amount of magnetic flux that can be generated by dynamo action, It is argued that in the limit of small diffusivity only a small amount of flux, many orders of magnitude less than the observed fluxes, can be created by dynamo processes.
Static Hydrophobic Cuprous Oxide Surface Fabricated via One-Step Laser-Induced Oxidation of a Copper Substrate

In this study, we developed a one-step method for fabricating hydrophobic surfaces on copper (Cu) substrates. Cuprous oxide (Cu2O) with low free energy was successfully formed after low-fluence laser direct irradiation. The formation of Cu2O enhanced the hydrophobicity of the Cu substrate surface, and the contact angle linearly increased with the proportion of Cu2O. The Cu2O fabricated by low-fluence laser treatment showed the same crystal plane orientation as the pristine Cu substrate, implying an epitaxial growth of Cu2O on a Cu substrate.
The cosmological evolution and luminosity function of X-ray selected active galactic nuclei

The cosmological evolution and the X-ray luminosity function of X-ray selected active galactic nuclei (AGNs) are derived and discussed. The sample used consists of 31 AGNs extracted from a fully identified sample of X-ray sources from the Einstein Observatory Medium Sensitivity Survey and is therefore exclusively defined by its X-ray properties. The distribution in space is found to be strongly nonuniform. The amount of cosmological evolution required by the X-ray data is derived in the framework of pure luminosity evolution and is found to be smaller than the amount determined from optically selected samples. The X-ray luminosity function is derived. It can be satisfactorily represented by a single power law only over a limited range of absolute luminosities. Evidence that the luminosity function flattens at low luminosity or steepens at high luminosity, or both, is presented and discussed.
Investment sensitivity to market uncertainty in the travel and tourism sector

Raising capital is critical for the future expansion of travel and tourism businesses which have been adversely impacted by the COVID-19 pandemic. Investors sold their travel and tourism stocks below true value due to falling earnings during the pandemic. This study compares the sensitivity of stocks in different sectors to uncertainty when they are aggregated into different exchange-traded funds (ETFs). This reduces the extent of firm-specific peculiarities arising from market overreactions to news, mergers and acquisitions through time. Although previous studies have highlighted the effect of uncertainty on the financial decisions of travel and tourism firms, this study identifies a ‘fear-triggering point’ in the VIX index above which travel and tourism ETFs enter the state of uncertainty. This study has thus important implications for raising capital and financing tourism businesses in the US equity market, particularly during heightened uncertainty.
Focus groups to explore the views of educational psychologists in training

Focus groups provide a creative means of carrying out group interviews. The use of focus groups is one of a number of methods which have recently become established within the social sciences, and even more recently in psychology. The paper describes the use of focus groups to elicit views of educational psychologists in training at the end of their Master’s training year. The method is discussed in detail, some issues are raised in relation to this method, and the particular study is described briefly.
Muscle Activation during the Squat Performed in Different Ranges of Motion by Women

Purpose: To analyze the muscle activation of the rectus femoris (RF), vastus lateralis (VL), gluteus maximus (GM), and biceps femoris (BF) in concentric and eccentric actions in the squat at 90° and 140° range of motion. Methods: Thirty-five women (32.9 ± 7.4 years; 64.5 ± 11.5 kg; 1.63 ± 0.1 m; BMI: 24.2 ± 2.9 kg/m2; %fat: 24.9 ± 6.5%) experienced exercise for at least eight weeks. Electrodes were positioned in standardized locations. The signals were acquired by an A/D SAS1000 V8 converter and the electromyographic activity normalized in the percentage of the highest produced value (%RMS). The data were analyzed using repeated measures two-way ANOVA, with effect size (η2) and differences calculated in percentage points (∆ p.p.). Results: The RF (p = 0.001; ∆ = 5.1 p.p.) and BF activation (p = 0.020; ∆ = 4.0 p.p.) was higher at 90° in the eccentric action. The RF showed an interaction between the range of motion and %RMS, with a large effect size (F = 37.9; p = 0.001; η2 = 0.485). The VL activation was higher at 140° (p = 0.005; ∆ = 3.9 p.p.) in the concentric action and higher at 90° (p = 0.006; ∆ = 3.7 p.p.) in the eccentric action, with a large effect size significant interaction (F = 21.3; p = 0.001; η2 = 0.485). The GM activation was higher at 90° in the concentric (p = 0.020; ∆ = 5.4 p.p.) and eccentric action (p = 0.022; ∆ = 41 p.p.). Conclusions: The biarticular muscles were influenced by the squat range only in the eccentric action of the movement, while the monoarticular muscles were influenced by the squat in both concentric and eccentric muscle action.
Pinning of recombination-enhanced dislocation motion in 4H–SiC: Role of Cu and EH1 complex

We report on the pinning of recombination-enhanced dislocation motion in 4H–SiC by the implantation of Cu. The Cu was found to be preferentially gettered at basal plane dislocations (BPDs). Both EH1 and Z1/2 center were detected in 4H–SiC by cathodoluminescence. It was noticed that the EH1 has high luminescence intensity at the central part of the BPDs, while the Z1/2 does not. The complex of Cu and EH1 is regarded to be the cause for the pinning effect. The possible reason for the pinning is discussed.
Superheterodyne detection of laser generated acoustic waves

A superheterodyne approach to the detection of laser generated acoustic waves is presented. An amplitude modulated laser source is used to generate high frequency, narrow bandwidth acoustic waves, and the resulting surface displacement is detected using a stabilized Michelson interferometer. The detection laser used in the interferometer is amplitude modulated at a frequency that is offset from the generation laser modulation frequency by a fixed amount, allowing for the optical down-conversion of the high frequency intensity modulation associated with acoustic wave propagation to a low and fixed intermediate frequency, thereby obviating the need for high frequency detection electronics. Results are presented demonstrating the approach for the detection of bulk and surface acoustic waves at frequencies of up to 1 GHz.
Spectral properties of periodic media in the large coupling limit

We investigate the band­gap structure and the integrated density of states for a class of periodic divergence type operators which, in the simplest case, are given by , acting in . We assume here that ωis an open, connected, periodic subset of and that the complement M ofωdoes not intersect the boundary of the fundamental period cellQ0. Operators of this type occur in simple models for heat conduction or propagation of acoustic waves in a metal with impurities like grains of sand or air bubbles, and in connectiion with photonic crystals. Among other results, we find that Tλ will always have at least one open gap,for λlarge (except for trivial cases). We also establish a connection between the band-gap nstructure of Tλ and the Dirichlet eigenvalue problem on
Kolmogorov's Hypotheses and Eulerian Turbulence Theory

It is argued that Eulerian formulations are intrinsically unsuited for deriving the Kolmogorov theory because low-order Eulerian moments do not express sufficiently well a statistical dependence of nonsimultaneous amplitudes that accompanies the convection of small spatial scales by large spatial scales. Illustration is made by applying the direct-interaction approximation and a related, higher Eulerian approximation to an idealized convection problem and to a modified Navier-Stokes equation. Convection effects of low wavenumbers on high wavenumbers are removed in the modified equation, and as a consequence the direct-interaction approximation for it yields the Kolmogorov spectrum. Low-order Lagrangian moments provide a promisingly more complete description of the convection of small spatial scales by large, and a search for satisfactory Lagrangian closure approxi-mations seems highly desirable.