Miracle-dz/UniFAR-FTUs huggingface dataset:
Circularly polarised OAM antenna using an aperture-coupled uniform circular array

Circularly polarised (CP) orbital angular momentum (OAM) antennas using aperture-coupled uniform circular array (UCA) are proposed to avoid the polarisation mismatch during the mobility and/or the space communications. A comprehensive derivation for ideal CP UCA is derived and numerical simulations are performed for further analysis. To validate the theoretical result and explore explicitly, the proposed prototype for ±1, ±2 mode OAM antennas with right-hand and left-hand circular polarisations are proposed and fabricated with measurements conducted, respectively. Measured radiation patterns, axial ratio versus elevation angle θ and the helical phase wavefronts are all favourable and exhibited. The transmission characteristics versus frequency f , relative azimuthal angel Δφ and distance D are all measured and analysed, which shows high isolations between different channels.
Filaments in the edge confinement region of TJ-II

Floating potential measurements from two remote reciprocating probes in the plasma edge region of the TJ-II stellarator are analyzed using the transfer entropy, revealing the spatial dimensions and propagation properties of filamentary structures. The results are corroborated by performing simulations with a resistive MHD model and analyzing data from synthetic diagnostics. The transfer entropy captures the rotation of the filaments and allows the calculating of their rotation velocity. This deduced velocity was compared to the (known) poloidal velocity of the plasma and showed a relatively good agreement.
PULMONARY FUNCTION CHANGES IN SANITARY WORKERS OF KANCHIPURAM POPULATION

Objectives: The main objective of this study is to evaluate the respiratory function of sanitary workers as they are most exposed to environmental air pollutants. Methods: The study was done among sanitary workers of Kanchipuram Municipality, Tamil Nadu, with 190 subjects, who were divided into two groups such as Group I and Group II. Group I with 96 sanitary workers and Group II with 94 as the control group with age- and morphometric-matched subjects. The subjects involved are both gender with the age group between 20 and 60 years. Various functional parameters, namely FVC, FEV1, FVC/ FEV1, FEF 25%, FEF50%, and FEF75%, were done using RMS Helios 3.1. 37 in the Physiology Department, Meenakshi Medical College and Research Institute. Institutional Ethical Committee approval was obtained from Institutional Human Ethical Committee. Results: The pulmonary findings showed a significant decrease in FVC, FEV1, FVC/FEV1, FEF 25%, FEF50%, and FEF75% when compared to the control group. Conclusion: The sanitary workers showed a significant decrease in the pulmonary function tests as they were exposed to a variety of solid waste particles which might have caused inflammatory and immunological responses with the small and large airways of the respiratory tract.
Using heterogeneity for obtaining the Medial Axis Transform of natural images

From Blum's Medial Axis Transform, that obtains the skeleton of binary images by joining the centers of all maximal inscribed disks in the shape, the AMAT was developed. The Appearance-MAT is a method that aims to compute the medial axes for natural images, as well as an appearance-based reconstruction. However, when considering the appearance, it deals only with color, and requires image smoothing to obtain a better result. As an approach to solving this problem, while abandoning the goal of reconstruction, we present and evaluate ten different methods for obtaining the medial axis transform, all based on the concept of heterogeneity. The idea behind this ensemble of methods is that in any natural image, any maximal inscribed disk should be homogeneous both in color and texture, while the disks that are not completely contained in an object should exhibit a much higher heterogeneity.
Low-carbon urban experiments from vision to reality: a systematic review of the literature from 2005 to 2020

ABSTRACT In recent decades, many cities have launched low-carbon pilot schemes to explore feasible local policies and actions that can be replicated on a larger scale to reduce the intensity of carbon emissions. This synthesis analysis reviews the global literature to analyse the interplay of prescriptive visions, practical responses, and evaluation methods of low-carbon urban experiments. Before 2015, low-carbon urban experiments were regarded as a sub-branch of sustainable development, and prescriptive visions were influenced by sustainability. Low-carbon urban experiments were used as an urban planning tool, and such urban planning concepts impacted the practical response and evaluation methods. After 2015, low-carbon urban experiments were influenced by many more disciplines. Planning still occupies the largest proportion of low-carbon practices, but more advanced technologies – in energy and other fields – have also been adopted and influence the evolution of low-carbon urban experiments. We find several driving factors, including political events and developments, technology change, and contributions from various disciplines including academic research. As carbon neutrality is the long-term target of many nations, achieving net-zero carbon dioxide emissions through prescriptive visions, practical responses, and evaluation methods in urban experiments demands further investigation, especially in developing countries. Key policy insights Low-carbon initiatives on a small scale are frequently practiced by local and national governments, which has reshaped the low-carbon agenda worldwide. Low-carbon development also demands efforts and commitment on the part of local urban governments to promote low-carbon development in its multiple dimensions. Policymakers at different levels of government and governance should focus on how to build on policy instruments in experimental pilots to take action at broader scales. Policymakers also need to adopt relevant indicators from social science in evaluation methods to reflect social sustainability and inclusiveness concerns in the evaluation of low-carbon urban development.
MARKETING DE RELACIONAMENTO: PRÁTICAS PARA CONQUISTAR O NOVO PERFIL DE CONSUMIDOR

Este artigo discute, à luz da revisão bibliográfica, práticas de marketing de relacionamento como estratégia para conquistar o novo perfil de consumidor, compreendendo seu comportamento e destacando práticas como personalização, segmentação, experiências positivas e uso de tecnologias. Autores mostram o sucesso dessa abordagem, enfatizando a importância da fidelidade do cliente e reputação da marca, concluindo que o marketing de relacionamento é essencial em um mercado competitivo e dinâmico.
Enhanced diffraction efficiency of mixed volume gratings with nanorod dopants in polymeric nanocomposite

We propose a method to improve the holographic performance of a volume holographic material by the particle-shape dependence of doped nanoparticles. Previously reported methods are based on changing the doping concentration of dopants and the diameter of nanoparticles or modifying the surface of nanoparticles. When transverse surface plasmon resonance of optimized gold nanorods shifts near the recording wavelength, experiments confirmed that enhancement of diffraction efficiency by efficient dopants of gold nanorods is better than that of gold nanospheres. The enhancement effects under optimal mixing conditions occur with a crucial factor of maximum absorption intensity at the recording wavelength using the particle-shape dependence of doping nanorods. The gold nanorods with an average diameter of 10 ± 2.1 nm and an average length of 34 ± 5 nm are doped in Phenanthrenequinone-doped poly(methyl methacrylate) photopolymers. The diffraction efficiency of volume holographic grating in the photopolymer doped w.
The Impact of Surface Heterogeneities and Land‐Atmosphere Interactions on Shallow Clouds Over ARM SGP Site

Continental shallow clouds are an important component of the land‐atmosphere coupled climate system because of their role in modulating energy and water budgets. The parameterization of these clouds in climate models presents a significant challenge. We evaluate the potential impact of subgrid‐scale (for climate models) land‐atmosphere interactions on shallow clouds using nested large‐eddy simulations (LESs). We compare LESs that allow for land‐atmosphere interactions to ones that artificially suppress all or part of them by smoothing out surface heterogeneities in surface heat, moisture and radiation fluxes within the domain. The LES domains are coupled to an interactive land surface model and nested inside a mesoscale domain. Three summertime shallow convection cases over the Department of Energy Atmospheric Radiation Measurement Facility's Southern Great Plains site are examined. A consistent increase in cloud water content is observed in all cases when surface heterogeneities and the land‐atmosphere interactions they induce in the LES domain are removed. By comparing experiments where only surface flux heterogeneities induced by cloud shadows are removed to ones where all surface flux heterogeneities are removed, we find that cloud shading‐induced surface heterogeneities can have a larger impact on shallow convection than static land surface heterogeneities in our cases. Furthermore, the impact of cloud shading on cloud water content and cloud size is found to vary significantly with the solar incidence angle. Our results suggest that the impact of cloud shadows needs to be considered when parameterizing land‐atmosphere interactions in the presence of shallow clouds for regional or global climate models.
AlGaN/GaN heterostructures with an AlGaN layer grown directly on reactive-ion-etched GaN showing a high electron mobility (>1300 cm2 V−1 s−1)

In this study, the metal–organic-vapor-phase-epitaxial growth behavior and electrical properties of AlGaN/GaN structures prepared by the growth of an AlGaN layer on a reactive-ion-etched (RIE) GaN surface without regrown GaN layers were investigated. The annealing of RIE-GaN surfaces in NH3 + H2 atmosphere, employed immediately before AlGaN growth, was a key process in obtaining a clean GaN surface for AlGaN growth, that is, in obtaining an electron mobility as high as 1350 cm2 V−1 s−1 in a fabricated AlGaN/RIE-GaN structure. High-electron-mobility transistors (HEMTs) were successfully fabricated with AlGaN/RIE-GaN wafers. With decreasing density of dotlike defects observed on the surfaces of AlGaN/RIE-GaN wafers, both two-dimensional electron gas properties of AlGaN/RIE-GaN structures and DC characteristics of HEMTs were markedly improved. Since dotlike defect density was markedly dependent on RIE lot, rather than on growth lot, surface contaminations of GaN during RIE were believed to be responsible for the formation of dotlike defects and, therefore, for the inferior electrical properties.
Neural Network Quadrature Signal Generator-Based Virtual Flux Estimation for Predictive Control of PWM Converters

In this article, a frequency-adaptive neural network-based virtual flux (FANN-VF) estimator is developed for sensorless control of a pulsewidth modulation converter under unbalanced and distorted grid conditions. This method exploits two parallel FANNs configured as quadrature signal generators. The VF fundamental positive and negative sequence components` are inherently separated in the estimator without employing any cascaded filters. A frequency-locked loop is introduced to accurately track the frequency variations. The estimated VF PNSCs are directly exploited to compute the power references in VF-based predictive direct power control scheme. The developed strategy ensures constant active power and sinusoidal current waveforms under nonideal grid conditions. Simulation and experimental tests are performed to verify the effectiveness of the proposed method.
Sliding Mode Control Design for Magnetic Levitation System

This paper presents a control system design for a magnetic levitation system (Maglev) or MLS using sliding mode control (SMC). The MLS problem of levitating the object in the air will be solved using the controller. Inductors used in MLS make the system have nonlinear characteristics. Thus, a nonlinear controller is the most suitable control design for MLS. SMC is one of the nonlinear controllers with good robustness and can handle any model mismatch. Based on simulation results with a step as input reference, MLS provided good system performances: 0.0991s rise time, 0.1712s settling time, and 0.0159 overshoot. Moreover, a prominent tracking control for sine wave reference was also shown. Although the augmented system had a chattering effect on the control signal, the chattering control signal did not affect MLS performances.
Ensuring the sustainability of sadaqah based crowdfunding platforms: The role of gamification and user experience

The inception of technology in the financial world has spawned many innovative financial activities, including crowdfunding. Since the emergence of crowdfunding, fundraising activities have flourished, enabling the implementation of many innovative projects and businesses, including agricultural projects. However, it is a major challenge for a crowdfunding platform to maintain the flow of donations. Most crowdfunding platforms lose half of their donors after their first donation. Therefore, this study proposes the use of gamification to increase and maintain individuals' donations on a crowdfunding platform. In addition, this study also examines the role of user experience as a mediating variable between gamification and donor intention on the crowdfunding platform. Data for this research were collected through a survey using a structured, self-administered questionnaire and involving 148 Muslim donors. Hypothesis testing revealed that gamification positively influences user experience, but not donation intention on a crowdfunding platform. Meanwhile, user experience successfully plays a mediating role. Thus, the results lead to a discussion on the justification of using gamification and suggestions for future research.
Metasurfaces and their applications

Abstract Metasurfaces are a topic of significant research and are used in various applications due to their unique ability to manipulate electromagnetic waves in microwave and optical frequencies. These artificial sheet materials, which are usually composed of metallic patches or dielectric etchings in planar or multi-layer configurations with subwavelength thickness, have the advantages of light weight, ease of fabrication, and ability to control wave propagation both on the surface and in the surrounding free space. Recent progress in the field has been classified by application and reviewed in this article. Starting with the development of frequency-selective surfaces and metamaterials, the unique capabilities of different kinds of metasurfaces have been highlighted. Surface impedance can be varied and manipulated by patterning the metasurface unit cells, which has broad applications in surface wave absorbers and surface waveguides. They also enable beam shaping in both transmission and reflection. Another important application is to radiate in a leaky wave mode as an antenna. Other applications of metasurfaces include cloaking, polarizers, and modulators. The controllable surface refractive index provided by metasurfaces can also be applied to lenses. When active and non-linear components are added to traditional metasurfaces, exceptional tunability and switching ability are enabled. Finally, metasurfaces allow applications in new forms of imaging.
Quantized Control for Networked Switched Systems With a More General Switching Rule

In this paper, a quantized control problem is investigated for a class of networked switched systems under the Round-Robin protocol. A more general switching rule is employed, under which the probability distribution of switching is dependent on both the sojourn time and the system mode. The Round-Robin protocol is adopted to accommodate the limitation of the network bandwidth from the viewpoint of fairness. The quantized measurement signal is sent to the controller as a feedback signal at each sampling instant. The aim of the problem addressed is to design a quantized controller such that, under the Round-Robin protocol, the switched system with the known joint distribution is mean-square stable. Considering the sojourn time and the periodicity of Round-Robin protocol, we present an interval-dependent periodic condition to guarantee the stability of addressed systems and then derive the explicit expressions of the controller for each subsystem by solving a set of matrix inequalities. Finally, a simulation example is given to demonstrate the effectiveness of the controller design method.
Fractal Based Triple Band High Gain Monopole Antenna

Abstract A novel triple-band microstrip fed planar monopole antenna is proposed and investigated. A fractal antenna is created by iterating a narrow pulse (NP) generator model at upper side of modified ground plane, which has a rhombic patch, for enhancing the bandwidth and gain. Three iterations are carried out to study the effects of fractal geometry on the antenna performance. The proposed antenna can operate over three frequency ranges viz, 3.34–4.8 GHz, 5.5–10.6 GHz and 13–14.96 GHz suitable for WLAN 5.2/5.8 GHz, WiMAX 3.5/5.5 GHz and X band applications respectively. Simulated and measured results are in good agreements with each others. Results show that antenna provides wide/ultra wide bandwidths, monopole like radiation patterns and very high antenna gains over the operating frequency bands.
Investigating the Relationship between Lightning and Mesocyclonic Rotation in Supercell Thunderstorms

AbstractRelationships between lightning and lightning jumps and physical updraft properties are frequently observed and generally understood. However, a more intensive characterization of how lightning relates to traditional radar-based metrics of storm intensity may provide further operational utility. This study addresses the supercell storm mode because of the intrinsic relationship between a supercell’s characteristic rotating updraft–downdraft couplet, or mesocyclone, and its prolific ability to produce severe weather. Lightning and radar measurements of a diverse sample of 19 supercell thunderstorms were used to assess the conceptual model that lightning and the mesocyclone may be linked by the updraft’s role in the formation and enhancement of each. Analysis of early stages of supercell development showed that the initial lightning jump occurred prior to the time of mesocyclogenesis inferred from three methods by median values of 5–10 min. Comparison between lightning jumps and subsequent increases.
Generation of Inflow Turbulence in Large-Eddy Simulations of Nonneutral Atmospheric Boundary Layers with the Cell Perturbation Method

Realistic multiscale simulations involve coupling of mesoscale and large-eddy simulation (LES) models, thus requiring efficient generation of turbulence in nested LES domains. Herein, we extend our previous work on the cell perturbation (CP) method to nonneutral atmospheric boundary layers (ABLs). A modified Richardson number scaling is proposed to determine the amplitude of the potential temperature perturbations in stable ABLs, with [Formula: see text] −1.0 overall providing optimum turbulence transition to a fully developed state (fetch reduced by a factor of 4–5, compared to the unperturbed cases). In the absence of perturbations, turbulence onset is triggered by a Kelvin–Helmholtz instability, typically occurring in the vicinity of the low-level jet maximum. It is found that a turbulent length scale [Formula: see text] can be used to more accurately estimate the optimum [Formula: see text], where q is the turbulence kinetic energy, and N is the Brunt–Väisälä frequency. In convective ABLs, a perturbation amplitude based on mixed layer temperature variance scaling is proposed: [Formula: see text]. For that criterion to be optimum, the ratio [Formula: see text], where [Formula: see text] is the wind speed at the top of the capping inversion, and [Formula: see text] is the convective velocity scale, needs to be incorporated: [Formula: see text]. This allows us to account for the competing roles of the surface thermal instability and the mean flow advection. For [Formula: see text] 10, the development fetch is reduced by a factor of [Formula: see text]6, while when [Formula: see text] 3, the use of the CP method does not provide a significant advantage in the ability to generate turbulence, provided a smooth mesoscale inflow.
Self-Attentive Local Aggregation Learning With Prototype Guided Regularization for Point Cloud Semantic Segmentation of High-Speed Railways

Point cloud semantic segmentation for railway infrastructures is an essential step towards establishing railway digital twins. Deep learning-based methods have shown great potential in this field compared to traditional methods that rely on hand-crafted features. However, deep learning-based methods for railway point clouds still face typical challenges that need to be addressed. In this regard, we propose a novel learning framework named SALAProNet, which consists of a set of effective and concise modular solutions. The first challenge addressed is the massive data scale of railway point clouds, which makes it difficult to directly process large-scale point clouds due to memory limitations. To solve this problem, we adapt efficient random sampling in the network and propose the Self-Attentive Aggregation (SAA) module based on an attention mechanism to greatly expand the receptive field, which covers the unsampled points and successfully retains information in a high-dimensional feature space. The second challenge is fine-grained segmentation, where we propose the Local Geometry Embedding (LGE) module to embed local geometry. With the help of context information provided by SAA, the network can perform fine-grained segmentation for railway infrastructures. The third challenge is the insufficient generalization ability of the network, where we propose a Prototype Guided Regularization (PGR) method to guide the network to segment the point cloud among railways with different construction standards. This method enhances the network’s interpretability and improves its generalization ability. We have validated our proposed framework through experiments on different datasets, and it outperforms state-of-the-art approaches.
Linear Models

This research aims to identify claims modeling in the compulsory car insurance branch in Egyptian insurance companies by using the data of Misr Property Insurance Company and Suez-Canal Insurance Company, using generalized linear models, and applying the Invasive Weed Optimization Algorithm (IWO) in selecting variables in the Poisson regression model, to present a set of proposals for using the Poisson regression model in evaluating compulsory car insurance pricing in Egyptian insurance companies, as well as revealing the nature and importance of claims modeling for the compulsory car insurance branch and focusing on the effectiveness of using generalized linear models in modeling claims for the compulsory car insurance branch, Finally, studying the impact of applying generalized linear models on modeling claims in general insurance,models for the purpose of modeling claims in insurance companies.