Miracle-dz/UniFAR-FTUs huggingface dataset:
Polariton-polariton scattering in organic microcavities at high excitation densities

Polariton-polariton scattering phenomena in organic strongly coupled microcavities have been theoretically assessed on the basis of the kinematic interaction of Frenkel excitons. Experiments have been focused on resonant pumping at magic angle, as well established in inorganic quantum-well microcavities, but insofar no experimental evidence of parametric amplification has been found. Here, we show that in J-aggregate-based microcavities a peculiar polariton-polariton scattering process applies, i.e., the scattering of two resonantly pumped polaritons toward a polariton of lower energy and a localized excitation of the exciton reservoir. This process, because of the localized nature of the final state, is not limited by momentum conservation, and we show that in a high-quality factor microcavity it could be exploited to setup resonant pumping experiments not requiring a magic angle configuration.
A transfer matrix method for free vibration analysis of Euler-Bernoulli beams with variable cross section

To perform vibration analysis, many structures could be modeled entirely or partially as beams with variable or constant cross section. In this study, the differential equations for free bending vibrations of straight beams with variable cross section are solved using Bessel’s functions. Then, the general equations for one-step conical beams are used together with corresponding equations of cylindrical beams to model multi-step beams with various boundary conditions. The natural frequencies of a cantilever conical beam, calculated using its derived field matrix, were shown to be close to those obtained experimentally. In addition, the influence of geometrical factors upon the value of fundamental frequencies is investigated for both cantilever and clamped-clamped conical beams. It was shown numerically that changing a cantilever cylindrical beam into a conical beam by reducing the diameter of the free end increases its fundamental natural frequency even though its rigidity decreases. This property was not observed in a clamped-clamped conical beam. Finally, the effectiveness of a proposed transfer matrix on the calculation of natural frequencies for a multi-step beam was verified. It is believed that the current method could help in the design of various structures, including beams with variable cross section.
Polymer Nanocomposites

Polymer nanocomposites (PNCs)–that is, nanopar ticles (spheres, rods, plates) dispersed in a polymer matrix–have garnered substantial academic and industrial in terest since their inception, circa 1990. This is due in large part to the incredible promise demonstrated by these early efforts: PNCs will not only expand the per form ance space of traditional filled polymers, but introduce completely new combinations of properties and thus enable new applications for plastics. Low volume additions (1–5%) of nanopar -ticles, such as layered silicates or carbon nanotubes, provide property enhancements with respect to the neat resin that are comparable to those achieved by conventional loadings (15–40%) of traditional fillers. The lower loadings facilitate proc essing and re duce component weight. Most important, though, is the unique value - added properties not normally possible with traditional fillers, such as reduced permeability, optical clarity, self - passivation, and increased re sis tance to oxidation and ablation. These characteristics have been transformed into numerous commercial suc cesses, including automotive parts, coatings, and flame retardants. This issue of the MRS Bulletin provides a snapshot of these exemplary successes, future opportunities, and the critical scientific challenges still to be addressed for these nanoscale multiphase systems. In addition, these ar ticles provide a perspective on the current status and future directions of polymer nanocomposite science and technology and their potential to move beyond additive concepts to designed ma te rials and devices with prescribed nanoscale composition and morphology.
IMAGING A MAGNETIC-BREAKOUT SOLAR ERUPTION

The fundamental mechanism initiating coronal mass ejections (CMEs) remains controversial. One of the leading theories is magnetic breakout, in which magnetic reconnection occurring high in the corona removes the confinement on an energized low-corona structure from the overlying magnetic field, thus allowing it to erupt. Here, we report critical observational evidence of this elusive breakout reconnection in a multi-polar magnetic configuration that leads to a CME and an X-class, long-duration flare. Its occurrence is supported by the presence of pairs of heated cusp-shaped loops around an X-type null point and signatures of reconnection inflows. Other peculiar features new to the breakout picture include sequential loop brightening, coronal hard X-rays at energies up to ∼100 keV, and extended high-corona X-rays above the later restored multi-polar structure. These observations, from a novel perspective with clarity never achieved before, present crucial clues to understanding the initiation mechanism of solar eruptions.
The limit theory of the energy-critical complex Ginzburg-Landau equation

We study the limit behavior of the solutions to energy-critical complex Ginzburg-Landau equation. We give a rigorous theory of the zero-dispersion limit from energy-critical complex Ginzburg-Landau equation to energy-critical nonlinear heat equation for dimensions 3 and 4 in both the defocusing and focusing cases by energy method. Furthermore, we also show the invisicid limit of energy-critical complex Ginzburg-Landau equation to energy-critical nonlinear Schr\"odinger equation for dimension 4 in the focusing case.
An Improved Microwave Radiative Transfer Model For Ocean Emissivity At Hurricane Force Surface Wind Speed

An electromagnetic model for predicting the microwave blackbody emission from the ocean surface under the forcing of strong surface winds in hurricanes is being developed. This ocean emissivity model will be incorporated into a larger radiative transfer model used to infer ocean surface wind speed and rain rate in hurricanes from remotely sensed radiometric brightness temperature. The model development is based on measurements obtained with the Stepped Frequency Microwave Radiometer (SFMR), which routinely flys on the National Oceanic and Atmospheric Administration’s hurricane hunter aircraft. This thesis presents the methods used in the wind speed model development and validation results for wind speeds up to 70 m/sec. The ocean emissivity model relates changes in measured C-band radiometric brightness temperatures to physical changes in the ocean surface. These surface modifications are the result of the drag of surface winds that roughen the sea surface, produce waves, and create white caps and foam from the breaking waves. SFMR brightness temperature measurements from hurricane flights and independent measurements of surface wind speed are used to define empirical relationships between microwave brightness temperature and surface wind speed. The wind speed model employs statistical regression techniques to develop a physics-based ocean emissivity model dependent on geophysical parameters, such as wind speed and sea surface temperature, and observational parameters, such as electromagnetic frequency, electromagnetic polarization, and incidence angle.
Error Vector Magnitude by Five Distortion Factors

The digital modulation signal is usually encountered in five kinds of distortion factors,including I/Q gain imbalance,phase offset,continuous wave interference,phase noise and additive Gaussian noise.Through mathematical derivation,a complete mathematical formula is obtained,to calculate EVM by five distortion factors.At the same time,two experiments are carried out,in conjunction with numerical simulation to verify the formula.Formula and measurement results fit well.
Super-hydrophobicity of PTFE Films Coated on an Etched Al Surface by Using a RF-magnetron Sputtering Method

Super-hydrophobic properties were achieved for RF-sputtered ultra-thin polytetrafluoroethylene(PTFE) films deposited on etched aluminum surfaces. The microstructural evolution created after etching was investigated by using field emission scanning electron microscopy (FE-SEM). In our investigation, super-hydrophobic surfaces with water contact angles higher than 150 were achieved on RF-sputtered ultra-thin PTFE films of less than 10 nm coated on aluminum(Al) surfaces etched for ten minutes with hydrochloric acid (HCl, 7 wt.% in H2O). X-ray photoelectron spectroscopy (XPS) analysis revealed the presence of a large quantity of -CF3 and -CF2 groups in the RF-sputtered PTFE films, which effectively reduced the surface energy of the etched aluminum. We concluded that the presence of a patterned morphology, along with the low surface energy on ultra-thin RF-sputtered PTFE coating, made the Al surface highly super-hydrophobic.
Elements of a physics case for a high-energy LHC

I outline the elements of a physics case for a high-energy upgrade to the LHC. The motivations are centered around the perspective of “blue chip” ideas that solve the hierarchy problem: technicolor-like theories, supersymmetry, and extra dimensions. In each case there is the prospect that going to higher energies is not only desirable but needed for discoveries. Nevertheless, the results from experimen t over the next few years, most especially at the LHC, will sharpen the arguments and enable a more enlightened decision between the various experimental options for the future. (Based on an October 14, 2010 presentation at the Malta HE LHC meeting.)
Adsorption using fly ash from stam power plants for acid mine drainage treatment

Acid mine drainage has a negative impact on the environment. Adsorption is an effective and efficient method for acid mine drainage treatment, besides that adsorption does not have a negative impact on the environment. This study aims to analyze the ability of fly ash from a steam power plant as an adsorbent in acid mine drainage treatment. Using experimental methods and batch adsorption mechanisms, with variations of adsorption parameters carried out including adsorbent dose, stirring time, and stirring speed. The test results show that fly ash is very effective in acid mine drainage treatment. Where there is an increase in pH and a decrease in the concentration of Mn and Fe metals in acid mine drainage to match the quality standard. The increase in pH was in the range of 6.3 to 7.4 with the highest effectiveness of 54.05%. In the reduction of Mnmetalthe highest effectiveness was 78.14%, while in Fe metal the highest effectiveness was 85.83%. Fly ash can be used and is very useful in reducing the impact on public health.
The pattern of material supply chain in post-disaster reconstruction: a case study in Indonesia’s disaster-prone area

The government, the community, or non-governmental organisations can all participate in the reconstruction process after a disaster. The management of material procurement and logistics may entail participation from several stakeholders. It may be crucial to a project’s success in reconstruction. A reliable supply chain is required to guarantee an appropriate building supply. The supply chain for building materials significantly impacts the course and results of reconstruction after a disaster. This study intends to map the post-disaster restoration process’s formation of the construction supply chain pattern. In order to detect potential issues and disturbances that could contribute to the failure of the post-disaster restoration process, the supply chain pattern for building materials is being mapped. The path of the supply chain for construction materials is undoubtedly significantly impacted by post-disaster environmental circumstances. Because it can impact project prices and timelines, the choice of building material suppliers is crucial in construction supply chain management. During the reconstruction process in disaster-affected areas, this research used qualitative approaches by conducting surveys and questionnaires to gather data and facts.
Design of Wireless Power Transfer System Based on LCC-S

Recently, wireless power transfer (WPT) technology has become a research hot spot due to its benefit of contactless power transfer. Firstly, for the sake of solving the problem of the small coupling coefficient of traditional orbital wireless power transfer systems, a new structure and control strategy of transceiver coil was proposed, and then the optimal parameters of system transmission efficiency were found out by comprehensive analysis of the LCC-S compensation circuit structure and equivalent circuit, and the correctness of the parameters was verified in MATLAB/Simulink simulation. Finally, an experimental prototype was built, and the experimental findings show that the wireless power transfer system based on LCC-S can realize voltage regulation control, the coupling coefficient is increased by 0.4 compared with the traditional orbital structure, and the transmission efficiency of this system is more than 80%.
A novel wideband circularly polarized dual-fed slot antenna with microstrip feeding network

This study presents the design of novel dual-fed circularly polarized (CP) antenna. This antenna consists of a tapered slot, a backside metal plate and a microstrip-fed delay line phase shifter. Based on the analysis of the radiation mechanism of antenna ground plane, the edge shape is optimized as a half-circle type to enhance the bandwidth of antenna gain and CP purity. The proposed antenna possesses a wideband return loss better than 10 dB in the range of 4.18–7.57 GHz, covering the bandwidth of axial ratio lower than 3 dB from 4.25 to 6.75 GHz. The measured antenna gain is approximately 9–10.5 dBic and the radiation patterns are broadside and consistent within the CP operating bandwidth.
Algebra lineal y descomposici on en valores singulares Linear Algebra and Singular Valued Decomposition

En este trabajo presentamos una propuesta entorno a cómo se puede utilizar la Descomposición en valores singulares de una matriz para desarrollar un temario de una asignatura de Álgebra lineal en un grado de ingenieŕıa. Para ello introducimos algunas técnicas especiales, resultados y ejemplos. In this work we present how we can use the Singular Valued Decomposition of a matrix as a main tool to develop a Linear algebra course in engineering. Some special techniques, results and examples are introduced in this setting. Palabras clave: modelización, álgebra lineal, descomposición en valores singulares, DVS.
Phase Transitions in Warped AdS 3 Gravity

We consider asymptotically Warped AdS3 black holes in Topologically Massive Grav- ity. We study their thermodynamic stability and show the existence of a Hawking-Page phase transition between the black hole and thermal background phases. At zero an- gular potential, the latter is shown to occur at the self-dual point of the dual Warped Conformal Field Theory partition function, in analogy with the phase transition for BTZ black holes in AdS3/CFT2. We also discuss how the central and vacuum charges can be obtained from inner horizon mechanics in the presence of a gravitational anomaly.
Grid Peak Load Shaving Method Considering EV Charging Uncertainty Based on Interval Optimization

With the rapid development of electric vehicles, more and more electric vehicles are entering people’s lives. However, the large-scale access of electric vehicles to the grid brings harm to the stability of grid operation, and the problem of how to guide the staggered charging of electric vehicles needs to be solved. In this paper, we consider the travel characteristics and charging characteristics of three different types of EVs: private cars, buses, and cabs, and set up a time-of-use tariff to guide EV users to charge reasonably, thus reducing the impact of charging load on the grid by cutting peaks and filling valleys. Since the charging load of EVs is an interval value, this paper introduces interval optimization theory, establishes an optimistic model and a pessimistic model, calculates the upper and lower bound of the interval respectively, and finds out the interval value of grid load after peak and valley reduction.
Optimal tracking performance of networked control systems with communication delays under channel input power constraint

The optimal tracking performance of networked control systems with communication delay and white Gaussian noise under the consideration of the channel input power constraint is studied in this paper. The tracking performance is measured by the energy of the system’s error signal and channel input power. The tracking performance is minimized by considering the channel input power constraint searching through all stabilizing two-parameter controllers. The optimal tracking performance of networked control systems under the communication delays, packet dropout and white Gaussian noise of the communication channel has been studied. The explicit expressions of the optimal tracking performance are obtained by applying the spectral factorization and inner–outer factorization techniques. It is shown that the optimal tracking performance depends on the non-minimum phase zeros, unstable poles of the given plant, communication delay, packet dropouts probability and white Gaussian noise. It is also shown that if the constraint of the communication channel does not exist, the optimal tracking performance reduces to the existing tracking performance of the control system without communication. The result shows how the communication delay, packet dropout probability and white Gaussian noise may fundamentally constrain a networked system’s tracking capability. Finally, some typical examples are given to illustrate the theoretical results.
Optimization of Control Parameters for Grid-forming Energy Storage Systems Based on Sensitivity Analysis

In recent years, the penetration rate of installed new energy generation has been increasing, the inertia of the system has been reduced, the damping has been weakened, and the anti-disturbance ability has been reduced, resulting in possible frequency oscillation of the system after disturbance, which brings potential problems to the safe and steady operation of power system. For this problem, a grid-forming control strategy of energy storage converter is proposed, based on virtual synchronization technology, to coordinate the parameter of virtual inertia and virtual damping. The simulation of a typical study case verifies the frequency control ability under different parameters and confirms the effectiveness of the parameter optimization.
Scientific CMOS Sensors in Astronomy: IMX455 and IMX411

Scientific complementary metal-oxide-semiconductor (CMOS) detectors have developed quickly in recent years thanks to their low cost and high availability. They also have some advantages over charge-coupled devices (CCDs), such as high frame rate or typically lower readout noise. These sensors started to be used in astronomy following the development of the first back-illuminated models. Therefore, it is worth studying their characteristics, advantages, and weaknesses. One of the most widespread CMOS sensors are those from the Sony IMX series, which are included in large astronomical survey projects based on small and fast telescopes because of their low cost, and capability for wide-field and high-cadence surveys. In this paper, we aim to characterize the IMX455M and IMX411M sensors, which are integrated into the QHY600 and QHY411 cameras, respectively, for use in astronomical observations. These are large (36 × 24 and 54 × 40 mm) native 16 bit sensors with 3.76 μm pixels and are sensitive in the optical range. We present the results of the laboratory characterization of both cameras. They showed a very low dark current of 0.011 and 0.007 e− px−1 s−1 @–10°C for the QHY600 and QHY411 cameras, respectively. They also show the presence of warm pixels, ∼0.024% in the QHY600 and 0.005% in the QHY411. Warm pixels proved to be stable and linear with exposure time, and are therefore easily corrected using dark frames. Pixels affected by the Salt & Pepper noise are ∼2% of the total and a method to correct for this effect is presented. Both cameras were attached to night telescopes and several on-sky tests were performed to prove their capabilities. On-sky tests demonstrate that these CMOS behave as well as CCDs of similar characteristics and (for example) they can attain photometric accuracies of a few mili-magnitudes.
Ferromagnetic eddy current damper of beam transversal vibrations

The paper deals with attenuation of transversal vibrations of a clamped-clamped beam loaded by a rigid mass at beam mid-point and excited by vertical force acting at beam mid-point. The novelty of treated approach is the use of a ferromagnetic conductor as the principal damping device. This is a different approach from that one used in contemporary research papers. Beyond vibration attenuation a concurrent shift in damped natural frequency due to the negative stiffness is observable. The theoretical results are complemented by measurements on a test stand. Up to 10 dB attenuation of the most marked resonance peak and frequency shift by up to 5 % to lower frequency was observed.
Supersymmetric mechanics?Volume 1: Supersymmetry, Noncommutativity and Matrix Models and Supersymmetric mechanics?Volume 2: The Attractor Mechanism and Space Time Singularities

With the development of the electronic archives in high-energy physics, there has been increasing questioning of the role of traditional publishing styles, particularly in the production of conference books. One aspect of traditional publishing that still receives wide appreciation, however, is in the production of well-focussed pedagogical material. The present two-volume edition, 'Supersymmetric Mechanics? Vol 1', edited by S Bellucci and 'Supersymmetric Mechanics? Vol 2', edited by S Bellucci, S Ferrara and A Marrani, is a good example of the kind of well-digested presentation that should still find its way into university libraries. This two-volume set presents the material of a set of pedagogical lectures presented at the INFN National Laboratory in Frascati over a two-year period on the subject of supersymmetric mechanics. The articles include the results of discussions with the attending students after the lectures. Overall, this makes for a useful compilation of material on a subject that underlies much of the current effort in supersymmetric approaches to cosmology and the unification programme. The first volume comprises articles on 'A journey through garden algebras' by S Bellucci, S J Gates Jr and E Orazi on linear supermultiplet realizations in supersymmetric mechanics,'Supersymmetric mechanics in superspace' by S Bellucci and S Krivonos, 'Noncommutative mechanics, Landau levels, twistors and Yang? Mills amplitudes' by V P Nair, 'Elements of (super) Hamiltonian formalism' by A Nersessian and 'Matrix mechanics' by C Sochichiu. The second volume consists entirely of a masterful presentation on 'The attractor mechanism and space time singularities' by S Ferrara. This presents a comprehensive and detailed overview of the structure of supersymmetric black hole solutions in supergravity, critical point structure in the scalar field moduli space and the thermodynamic consequences. This second volume alone makes the set a worthwhile addition to the research library of any university active in fundamental theoretical physics.