Miracle-dz/UniFAR-FTUs huggingface dataset:
A Generalized Gazi–Passino Model With Coordinate-Coupling Matrices for Swarm Formation With Rotation Behavior

In this article, a kinematic continuous time swarm model is considered by extending the results in the paper “A class of attractions/repulsion functions for stable swarm aggregations” (as shown in the International Journal of Control, vol. 77, pages 1567–1579). The extension regards a more general class of attraction/repulsion functions that can be used to explain the formation of rotational patterns in a swarm of agents. The main characteristic of this model is the introduction of two coordinate-coupling matrices weighting both the attractive and the repulsive interactions among the agents. A stability analysis is presented to characterize the swarm in terms of size and cohesiveness. Moreover, a class of attraction/repulsion functions is presented to guarantee the cohesiveness of the swarm in a polytopic region and a steady-state motion of the agents in a rotational frame around the swarm centroid. Numerical simulations are provided to illustrate the obtained results.
Dual-Differential SIW-Fed Leaky-wave Antenna with Dual-Polarization for Full-Duplex Applications

This paper presents a dual-polarized leaky-wave antenna (LWA) for full-duplex (FD) communication applications. The design is based on slots fed by substrate integrated waveguides (SIWs) with differential feeding. This SIW feeding and slot arrangement, which realizes two orthogonal and linear polarizations in the far field, is then used to excite leaky-wave (LW) fields on a superstrate constituted by a printed partially reflective surface (PRS). The LWA provides -10 dB impedance matching from 24 to 28 GHz (more than 15%), with isolation levels greater than 50 dB and with realized gains of 16 dBi. The proposed LWA is also compact, low profile, wideband, and offers a convenient feeding approach making the design useful for FD communications, dual-polarization, and 5G systems.
Asymmetric Group Key Agreement Protocol Based on Blockchain and Attribute for Industrial Internet of Things

In the era of Industry 4.0, the Industrial Internet of Things (IIoT) has been applied to help physical entities to access real-time data in the network and share critical information. However, both the decentralization of IIoT and the heterogeneity of different devices constituting IIoT also pose a serious threat to secure communication between entities. Although the encryption technologies can ensure the confidentiality of communication data, the security of key becomes more important for devices in IIoT. Recently, some asymmetric group key agreement (AGKA) protocols have been proposed to negotiate a common encryption key for group members, and each group member holds its decryption key. However, the existing AGKA protocols fail to effectively control the access of agreement participants in IIoT. To solve this problem, in this article, we propose an AGKA protocol based on blockchain and attribute for IIoT. The proposed protocol not only realizes the access control of agreement participants but also realizes the automation of access control, the tamper resistance, and the nonrepudiation of the agreement process. The security and performance analysis of the proposed protocol show that it is more secure and effective compared with the existing AGKA protocols.
Holomorphic parafermions in the Potts model and stochastic Loewner evolution

We analyse parafermionic operators in the Q-state Potts model from three different perspectives. First, we explicitly construct lattice holomorphic observables in the Fortuin–Kasteleyn representation, and point out some special simplifying features of the particular case Q = 2 (Ising model). In particular, away from criticality, we find a lattice generalization of the massive Majorana fermion equation. We also compare the parafermionic scaling dimensions with known results from conformal field theory and Coulomb gas methods in the continuum. Finally, we show that expectation values of these parafermions correspond to local observables of the stochastic Loewner evolution process which is conjectured to describe the scaling limit of the Q-state Potts model.
Neutral Winds in the Lower Thermosphere From Dynamics Explorer 2 (Paper 92GL01023)

Doppler line profile measurements of the OI 557.7 nm "green line" emission, made by the Fabry-Perot interferometer on Dynamics Explorer 2, have provided altitude profiles of the meridional component of the lower- thermospheric neutral wind. The wind inversion technique of Nardi (1991) has been used to extract the neutral wind profiles from the line-of-sight measurements. Individual . 557.7 nm Doppler line profiles and inverted volume-emission-rate and neutral-wind profiles are presented. Neutral wind measurements from the-120 km altitude level, obtained on multiple orbital passes over the summer hemisphere polar region, have been merged to produce a synthesized averaged "vector" wind field in geomagnetic coordinates. The wind pattern exhibits a region of anticyclonic vorticity in the daytime sector of the magnetic polar cap. Averaged winds of-300 m/sec in the equatorial direction are observed in the early morning sector. The satellite winds are in reasonable agreement with the predictions of the NCAR and UCL thermosphere general circulation models, with significant regional discrepancies evident in both magnitude and direction.
On the Sensitivity of RCS to the Wall Conductivity of Highly-Conductive Structures with Voids

One of the recently introduced camera-box benchmarks is used to investigate the sensitivity of radar cross section (RCS) to the wall conductivity of highly-conductive structures with voids. Simulation results show that the effect of wall conductivity varies with look angle and frequency: The object’s monostatic RCS, a function of both the housing and the void, is insensitive to the wall conductivity at angles blind to the void or frequencies where the modes in the void are below cut off. The RCS is sensitive to wall conductivity up to remarkably high values, however, at angles aware of the void and frequencies where the void supports modes; e.g., distinct differences in patterns are observed at void-aware angles at 10.24 GHz until conductivity is higher than 104 S/m. The study indicates that simulations that use the perfect-electric-conductor simplification may not accurately compute scattering from platforms containing even highly-conductive structures with voids.
Numerical Study of Stimulated Brillouin Scattering in Optical Microcavities Made of Telecommunication Fibres

We numerically studied stimulated Brillouin scattering processes up to the 5th order is microcavities with various realistic diameters and Q-factors made of standard telecommunication fibres. Pump power thresholds were simulated for different parameters of the system. The larger the microcavity and lower Q-factors, the higher pump power thresholds are. It is also shown that thresholds strongly depend on pump detuning. For a microcavity with a diameter of 200 μm and Q-factor of 5×107, threshold pump powers for the 1st order stimulated scattering are 0.3 and 30 mW for pump detunings 0 (exact resonance) and 20×2π MHz, respectively.
Study on The Difference of Bodily Surface Field Intensity for Live Working Operators of UHVDC Transmission Line Considering Meteorological Factors

During live working on UHVDC lines, If the field intensity of a certain part exceeds some certain threshold, it will cause discomfort and even pose a threat to personal safety. As UHVDC transmission has a long span, the climatic environment of regions through which the UHVDC line passes is complex and changeable, the effect degree of meteorological factors varies greatly with different bodily parts. In order to explore the difference in the field intensity of different locations of operators with the changes in meteorological conditions, firstly, a simulation model is built on the basis of the actual situations of the UHVDC line, and its correctness is verified by comparing it with the measured data; secondly, a large-scale simulation of the bodily surface field intensity of live working operators under different atmospheric parameters is carried out, and the influence weight for each meteorological factor is distributed by the combination weighting; thirdly, the correlation between the bodily surface field intensity and meteorological factors is analyzed through the use of the grey relational analysis (GRA) to construct the evaluation matrix; finally, the intensity of the personnel electric field difference of each part of the live working operator is evaluated by combining the grey relational analysis with technique for order preference by similarity to ideal solution (TOPSIS). The result turns out that the field intensity of the feet and head is more susceptible to meteorological factors. Because the head is highly sensitive to field intensity and its protective barrier is relatively weak, it is necessary to focus on strengthening the field intensity monitoring and safety prevention and control of the operator's head. The research can provide a reference for constructing a complete safety protection system for live working operators.
Simulation of ac conductivity of monolayer MoS2 at terahertz frequencies

We present a multiphysics numerical tool for calculating the terahertz (THz) conductivity of transition-metal dichalcogenides (TMDs). The tool combines the ensemble Monte Carlo (EMC) technique for carrier transport with a three-dimensional finite-difference-time-domain (FDTD) solver for electromagnetic fields. We use the coupled EMC–FDTD technique to calculate the frequency-dependent conductivity in the terahertz range for monolayer MoS2, both for suspended layers and for layers supported on the commonly used silicon-dioxide substrate.
Extending Machine Learning Based RF Coverage Predictions to 3D

This paper discusses recent advancements made in the fast prediction of signal power in mmWave communications environments. Using machine learning (ML) it is possible to train models that provide power estimates with both good accuracy and with real-time simulation speeds. Work involving improved training data pre-processing as well as 3D predictions with arbitrary transmitter height is discussed.
PMSM Adaptive Sliding Mode Controller Based on Improved Linear Dead Time Compensation

Aiming at the issue of the sliding mode observer (SMO) being sensitive to the motor model parameters at low speeds, a rotor position observation method based on resistance adaptive SMO and considering the influence of inverter dead time is designed in this paper. In this method, the online resistance identification is introduced into the conventional SMO, the resistance parameters of the SMO are modified in real-time, and the online resistance identification algorithm is designed by using the Lyapunov function. An enhanced linear dead time compensation method is proposed to improve the resistance adaptive SMO and eliminate the voltage error between the estimated and the actual motor models in order to address the impact of inverter dead time on the voltage parameters in the estimation model at low speeds. Simulation results show that the online resistance identification and dead time compensation can significantly improve the accuracy of sensorless speed control at low speeds, and the dead time compensation can also improve the accuracy of online resistance identification.
Scattering of atomic matter waves from ridged surfaces (11 pages)

Motivated by recent experiments that demonstrated a strongly enhanced reflection efficiency of atoms on microfabricated, gratinglike surface structures, we develop a detailed description of the scattering of atomic matter waves on such structures. We start with a simple model that describes the ridged surface as an equivalent absorbing medium. This model correctly predicts the experimentally observed scaling and magnitude of the reflection efficiency. We then calculate the accurate solutions for the Fresnel diffraction of waves at grazing incidence at a periodic set of idealized, parallel edges. Both numerical and analytical solutions are presented. The specular reflectivity and its phase, as well as the efficiencies of higher diffraction orders are calculated. We compare our results to experimental data in a wide range of parameters. We extend the model including the finite size of the grating ridges and the van der Waals attraction and suggest a more general estimate of the reflection coefficient.
Reaching the boundary between stellar kinematic groups and very wide binaries - The Washington double stars with the widest angular separations

Aims. I look for and characterise very wide binaries and multiple systems with projected physical separations larger than $s = 0.1$ pc, which is generally believed to be a sharp upper limit to the distribution of wide binary semimajor axes. Methods. I investigated in detail 30 Washington double stars with angular separations of ρ > 1000 arcsec. I discarded 23 of them as probably unbound systems based on discordant astrometry, photometry, spectral types, and radial velocities. The remaining seven systems were subject to a comprehensive data compilation and derivation (multi-wavelength photometry, heliocentric distance, multiplicity, age, mass, metallicity, membership in a young kinematic group). Results. Of the seven very wide systems, six have projected physical separations greater than the hypothetical cutoff at $s = 0.1$ pc and four have separations $s > 0.2$ pc. Although there are two systems in young kinematic groups (namely HD 136654 and BD+32 2572 in the Hyades Supercluster, and AU Mic and AT Mic AB in the β Pictoris moving group), there is no clear prevalence of young systems ( τ < 1 Ga) among these very wide binaries. Finally, I compare the binding energies of the seven systems with those of other weakly bound systems in the field.
The Mie theory : basics and applications

Gustav Mie and Mie theory. - Nobel nano-particles on plane surfaces and plasmon resonances. - Mie theory and Gaussian laser beam scattering. - The extension of Mie theory to multiple spheres. - Mie theory, a review. - From theories by Lorenz and Mie to ontological under-determination of theories by experiments. - Predicting the appearance of materials using Lorenz-Mie theory. - Rainbows, coronas and glories. - Optical force and torque on single and aggregated spheres: The trapping issue. - Dipole re-radiation effects in surface enhanced Raman scattering. - Mie theory extensions.
Integrated Analyses of m6A Regulator-Based Signature on Its Clinical Application and Immunogenomic Landscape in Stomach Adenocarcinoma

Background The whole tumor microenvironment (TME) infiltration features monitored by integrated roles of different RNA N6-methyladenosine (m6A) regulators remain elusive. Our study is aimed at exploring the association between m6A modification patterns, TME cell-infiltrating levels, and patients' prognosis in stomach adenocarcinoma (STAD) patients. Methods Consensus clustering was performed based on the integrated analyses of 17 m6A regulators and 229 m6A-related hallmark genes in STAD (The Cancer Genome Atlas (TCGA) cohort, n = 443; Gene Expression Omnibus (GEO) GSE57303, n = 70, GSE62254 n = 300, and GSE84437 n = 433). A m6ASig scoring system was calculated by the principal component analysis (PCA), and its prognostic value was validated in an independent dataset GES15459. Results Three m6A clusters were identified among 1246 STAD patients, which had significant overall survival (OS) differences and demonstrated different TME immune cell infiltration and biological behaviors. According to the m6ASig score, which was generated from the m6A-related hallmark genes, STAD patients were divided into the high-m6ASig group (n = 585) and low-m6ASig group (n = 586). Patients in the high-m6ASig group had a notably prolonged OS and higher immune cell infiltration. Moreover, patients with higher m6ASig score were associated with higher microsatellite instability (MSI); higher PD-L1, CTLA4, and ERBB2 expressions; and greater tumor mutation burden (TMB). Patients with higher m6ASig score demonstrated a better immune response and drug sensitivity. Conclusion Our m6ASig scoring system could characterize TME immune cell infiltration, thus predict patient's prognosis and immunotherapy and chemotherapy efficacy, offering a novel tool for the individualized therapeutic implications for STAD patients.
Solving Semide nite Programs via Nonlinear Programming

In a semidefinite programming (SDP) problem, a linear function of a symmetric matrix variable X is minimized subject to linear equality constraints on X and the essential constraint that X be positive semidefinite. We show how a special class of semidefinite programming (SDP) problems can be transformed into well-behaved nonlinear programs over ”orthants” <++×< , where n is the size of the matrices involved in the problem and N is a nonnegative integer dependent upon the problem. The class of transformable problems includes most, if not all, instances of SDP relaxations of combinatorial optimization problems with binary variables as well as other important SDP problems. We also develop interior point methods for solving this class of SDP problems. These new interior point methods have the advantage of working entirely within the space of the transformed problem while still maintaining close ties with the original SDP. Under very mild and reasonable assumptions, global convergence of these methods is proved. Strong computational results are presented to show that the method is very promising. (This is joint work with Sam Burer and Yin Zhang.)
Postharvest conservation of strawberries from three new accessions cultivated in the south of Minas Gerais – Brazil

The objective of this work was to evaluate the postharvest conservation of fruits of three strawberry accessions (NP4, NP9, NP15) under two storage conditions, comparing them with the fruits of cv. Oso Grande (control treatment). The fruits, with 75% of their surface with red color, were harvested, selected and placed in PET containers with lid and stored under ambient conditions (20±3 °C and 81±7% relative humidity) and under refrigeration (5± 1 ºC and 90±4% relative humidity). During the 11 days of storage, the following evaluations were carried out: total soluble solids (TSS), total titratable acidity (TTA), TSS/TTA ratio, pH and the loss of mass of fruits kept under different storage conditions. Under environmental conditions, the maximum longevity of the fruits was three days and the best preservation was observed in the fruits of the NP9 strawberry tree. Under refrigeration, the longevity of the fruits extended until the 11th day, when the fruits of the NP9 and NP15 access strawberries exhibited better characteristics when compared to the fruits of NP4 and 'Oso Grande', thus representing a new option for growing fruits for consumption in natura for producers in southern Minas Gerais.
The Role of Mothers in Early Childhood Education amidst the COVID-19 Pandemic in Indonesia

The spread of COVID-19 impacted education sector in which teachers cannot carry out the face-to-face (offline) learning. Consequently, teaching and learning activities are conducted online which students access from home with the help of their main carers especially mothers. This study aims to explore the role of Indonesian mothers in their early childhood education amidst the COVID-19 pandemic. It reports challenges experienced by mothers in accompanying their children’s online study from home. Data were collected from semi-structured interviews with six Indonesian mothers. The study finds that the roles of mothers to their children’s online learning include providing the children’s needs in online classes, assisting children to do the assignments, managing time between house chores and kid’s schooling, and concerning for mental kid’s health and families. It is clear that Indonesian moms encountered myriad of challenges during their children’s online class in the COVID-19 pandemic time. These challenges were worsened by the lack of technical expertise, lack of training and support, lack of preparation among children, difficulties in managing the time between children’ school and other works, and problems with internet connection. This study proposes an involvement and collaboration between parents, so that online learning can be facilitated by both fathers and mothers. This collaboration is needed to ensure the successful online learning for the children, especially during the COVID-19 pandemic.
Influence of Lossy Ground on High-Frequency Induced Voltages on Aboveground Pipelines by Nearby Overhead Transmission Lines

The electromagnetic interference (EMI) of overhead transmission lines (OHLs) to aboveground pipelines sharing the same right-of-ways has been a research topic for many years. Most studies focus on investigations of the induced currents and voltages at the mains frequency (50/60 Hz). However, significant voltage levels can also be induced, when the pipeline is subject to high-frequency excitation. The representation of earth conduction effects is very important to estimate accurately the level of the EMI. This article presents a detailed high-frequency analysis of OHL/pipeline configurations taking into consideration the frequency-dependent (FD) soil properties. Wise's earth formulation is adopted for the calculation of the earth return impedances and shunt admittances. Propagation characteristics, frequency-domain, and transient responses are calculated by using both the FD soil models and constant soil properties, as well as the classical transmission line approach of Carson. Frequency-domain responses calculated with Wise's formulation are compared against those obtained using the MoM-SO method of EMTP software.
Vortices in rotating optical lattices: commensurability, hysteresis, and proximity to the Mott State

Quantized vortices stunningly illustrate the coherent nature of a superfluid Bose condensate of alkali atoms. Introducing an optical lattice depletes this coherence. Consequently, novel vortex physics may emerge in an experiment on a harmonically trapped gas in the presence of a rotating optical lattice. The most dramatic effects would occur in proximity to the Mott state, an interaction dominated insulator with a fixed integer number of particles per site. We model such a rotating gas, showing that the lattice-induced spatial profile of the superfluid density drives a gross rearrangement of vortices. For example, instead of the uniform vortex lattices commonly seen in experiments, we find parameters for which the vortices all sit at a fixed distance from the center of the trap, forming a ring. Similarly, they can coalesce at the center, forming a giant vortex. We find that the properties of this system are hysteretic, even far from the Mott state. We explain this hysteresis in terms of vortex pinning, commensurability between vortex density and pinning site density, and energy barriers against changing the number of vortices. Finally, we model time-of-flight expansion, demonstrating the experimental observability of our predictions.
The effects of temperature on supersonic jet noise emission

This paper examines the generation of sound produced by high temperature supersonic jets. In particular, the question of the importance of supersonic instability waves to noise emission is considered relative to the role of Kelvin-Helmholtz (K-H) instability waves. Here, these waves are taken to be synonymous with the Mach emission process. Jet total temperatures from 313 to 1534 K are investigated using an axisymmetric water cooled supersonic nozzle designed for Mach 2. The aerodynamic and acoustic results of this study indicate that the dominant noise contributors are the K-H waves over the entire temperature range. Good agreement between measured and numerically predicted plume properties are obtained and an elliptic nozzle is used to demonstrate reduction of the K-H waves.