Miracle-dz/UniFAR-FTUs huggingface dataset:
Spin splitting in a p-type quantum well with built-in electric field and microscopic inversion asymmetry

The strain dependence of the spin splitting of hole subbands in modulation-doped asymmetric lattice-matched ${\mathrm{In}}_{\mathrm{x}}$${\mathrm{Ga}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$As/${\mathrm{In}}_{\mathrm{x}}$${\mathrm{Ga}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{As}}_{\mathrm{y}}$${\mathrm{P}}_{1\mathrm{\ensuremath{-}}\mathrm{y}}$ quantum wells on lattice-mismatched ${\mathrm{In}}_{\mathrm{x}}$${\mathrm{Ga}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{As}}_{\mathrm{y}}$${\mathrm{P}}_{1\mathrm{\ensuremath{-}}\mathrm{y}}$ substrates is investigated theoretically using a 6\ifmmode\times\else\texttimes\fi{}6 Luttinger-Kohn Hamiltonian. The influence of the built-in electric field, the microscopic inversion asymmetry of the zinc-blende lattice, and the strain are taken into account and analyzed for different widths of the quantum wells. The spin splitting is dominated by the effects of the electric field for compressive strain and small tensile strain. For large tensile strain the microscopic inversion asymmetry is the most important origin of spin splitting. A local maximum of spin splitting is located at small tensile strain. For large compressive strain the spin splitting is strongly suppressed whereas for large tensile strain the spin splitting increases with the absolute value of strain. However, the spin splitting vanishes completely in some directions for tensile strain.
On the minimum expected quantity for the validity of the chi-squared test in 2 2 2 tables

A 2 2 2 contingency table can often be analysed in an exact fashion by using Fisher's exact test and in an approximate fashion by using the chi-squared test with Yates' continuity correction, and it is traditionally held that the approximation is valid when the minimum expected quantity E is E S 5. Unfortunately, little research has been carried out into this belief, other than that it is necessary to establish a bound E>E*, that the condition E S 5 may not be the most appropriate (Martín Andrés et al., 1992) and that E* is not a constant, but usually increasing with the growth of the sample size (Martín Andrés & Herranz Tejedor, 1997). In this paper, the authors conduct a theoretical experimental study from which they ascertain that E* value (which is very variable and frequently quite a lot greater than 5) is strongly related to the magnitude of the skewness of the underlying hypergeometric distribution, and that bounding the skewness is equivalent to bounding E (which is the best control procedure). The study enables estimating the expression for the above-mentioned E* (which in turn depends on the number of tails in the test, the alpha error used, the total sample size, and the minimum marginal imbalance) to be estimated. Also the authors show that E* increases generally with the sample size and with the marginal imbalance, although it does reach a maximum. Some general and very conservative validity conditions are E S 35.53 (one-tailed test) and E S 7.45 (two-tailed test) for alpha nominal errors in 1% h f h 10%. The traditional condition E S 5 is only valid when the samples are small and one of the marginals is very balanced; alternatively, the condition E S 5.5 is valid for small samples or a very balanced marginal. Finally, it is proved that the chi-squared test is always valid in tables where both marginals are balanced, and that the maximum skewness permitted is related to the maximum value of the bound E*, to its value for tables with at least one balanced marginal and to the minimum value that those marginals must have (in non-balanced tables) for the chi-squared test to be valid.
A carrier escape study from InP/InGaAs single quantum well solar cells

Carrier escape from InP/AlGaAs single quantum well structures is studied by means of simultaneous steady state photocurrent and photoluminescence measurements. The activation energy for escape is measured for the first time in this system. The photoluminescence from the InGaAs wells indicates that a significant number of carriers do not escape at room temperature thus affecting the temperature dependence of the cell. An estimate of the nonradiative efficiency of the device studied is given as a function of bias and temperature. The relevance to new applications is discussed.
Metastable State of Supercooled Plasma

The computer ab initio simulation and analytical theory, that revealed unexpected non-ergodic properties of a classical Coulomb plasma, is overviewed. The results of a many-charged-particles system simulation predict the possible existence of a real metastable plasma, supercooled with respect to its ionization degree. The three-body recombination at this state is suppressed. The existence of such a plasma state is a consequence of the entropy conservation in isolated Hamiltonian systems free from any stochastic action from the outside (external stochastic disturbance). The occurrence of a metastable supercooled plasma (rather similar to a supercooled vapor or superheated liquid) depends on two conditions: First, all the charged particles should behave exactly according to the laws of classical mechanics (hence, most negatively-charged particles should preferably be heavy ions). Second, the plasma ionization degree should be sufficiently high (> 10−3). It is shown from thermodynamic consideration that a mixture of supercooled plasma with a perfect (ideal) gas might form a plasmoid of the ball-lightning type.
Indirect sandwich aptamer assay coupled structurally stabilized hairpin assisted hybridization chain reaction for femtomolar detection of cardiac troponin I

In this study, we present the development of a rapid, sensitive, and precise method for the detection of cardiac troponin I, which is crucial for early identification and intervention in acute myocardial infarction, particularly in resource-limited settings. Our approach employs a colorimetric, ultrasensitive indirect sandwich aptamer assay for cardiac troponin I detection. To enhance the structural stability of hairpins and prevent nonspecific amplification, we incorporated trimeric DNAzyme sequences required for the generation of color into the hairpin loop regions. This novel technique has the potential to significantly improve diagnostic capabilities for acute myocardial infarction in resource-constrained areas.
Light bullets from Mid-IR femtosecond filament in air

We numerically investigated the formation of light bullets under filamentation of 3.8- μm femtosecond pulse in presence of anomalous GVD in humid air. The dispersion of humid air in infrared spectral region was characterized by model fits of the real part of refractive index from HITRAN database. The fit for the 2.8-4.2 μm region describes the areas of anomalous GVD near 3.1 μm and 4 μm in humid air. During the nonlinear propagation of femtosecond pulse in humid air, the compressed in space and time wave packet – light bullet – appears in the central time layers of the pulse and moves to the pulse tail. The duration of light bullet reaches the few-cycle value and the energy fluence in the in the light bullet cross-section is above 1 J/cm2. Together with the light bullet formation the spectrum of the pulse broadens strongly and covers the spectral region from 3 μm to 5 μm. The interference model was used for investigation of the frequency-angular distribution of the supercontinuum spectrum components.
ALPHA‐IODIC ACID: A SOLUTION‐GROWN CRYSTAL WITH A HIGH FIGURE OF MERIT FOR ACOUSTO‐OPTIC DEVICE APPLICATIONS

The photoelastic properties of α‐HIO3 have been measured and the applicability of the material for acousto‐optic device applications determined. In the blue and green portions of the visible the material has the highest figure of merit, n6p2/ρv3, of any known crystal, approximately twelve times that of LiNbO3 and fifty times that of fused silica. Other desirable properties for these applications include (a) the availability of large solution‐grown single crystals of high optical quality, (b) low acoustic and optic losses, and (c) the absence of ``optical damage. ''A simple acoustically driver beam deflector was also constructed to demonstrate the potential of this material. It was found that 70% of a 0.63‐μ laser beam could be deflected, over a bandwidth of 55 MHz, with an electrical drive power of 265 mW, while 70% of a 0.488‐μ laser beam could be deflected over the same bandwidth with 94 mW of electrical power.
Generalised Variance Function Estimation for Binary Variables in Large‐Scale Sample Surveys

Generalised variance function (GVF) models are data analysis techniques often used in large‐scale sample surveys to approximate the design variance of point estimators for population means and proportions. Some potential advantages of the GVF approach include operational simplicity, more stable sampling errors estimates and providing a convenient method of summarising results when a high number of survey variables is considered. In this paper, several parametric and nonparametric methods for GVF estimation with binary variables are proposed and compared. The behavior of these estimators is analysed under heteroscedasticity and in the presence of outliers and influential observations. An empirical study based on the annual survey of living conditions in Galicia (a region in the northwest of Spain) illustrates the behaviour of the proposed estimators.
Enhanced situational awareness in the maritime domain: an agent-based approach for situation management

Maritime Domain Awareness is important for both civilian and military applications. An important part of MDA is detection of unusual vessel activities such as piracy, smuggling, poaching, collisions, etc. Today's interconnected sensorsystems provide us with huge amounts of information over large geographical areas which can make the operators reach their cognitive capacity and start to miss important events. We propose and agent-based situation management system that automatically analyse sensor information to detect unusual activity and anomalies. The system combines knowledge-based detection with data-driven anomaly detection. The system is evaluated using information from both radar and AIS sensors.
Practical Three-Dimensional Mesh Generation Using Transfinite Interpolation

A computational procedure for generating three-dimensional nonorthogonal surface-fitted mesh systems is presented. The method is based on the concept of transfinite interpolation and makes use of normal derivatives of the mapping function at the boundaries to obtain the desired mesh control. A brief description of the theory is presented together with 2D examples to demonstrate the general principles. The generation of 3D meshes of $O-O$ type around wings and schematic wing-fuselage configurations is described in detail and several computed examples are shown.
Radio and Optical Follow-up Observations of a Uniform Radio Transient Search: Implications for Gamma-Ray Bursts and Supernovae

We present the first full characterization of the transient radio sky via radio and optical follow-up observations of all the possible radio transients we have discovered in a survey covering ≈1/17 of the sky. The two confirmed radio transients turn out to be an optically obscured radio supernova (SN) in the nearby galaxy NGC 4216, the first such event to be discovered by a wide-field radio survey, and a source not associated with a bright host galaxy. We speculate that this second source may be a flare from a peculiar radio-loud AGN, or a burst from an unusual Galactic compact object, but its nature merits further study. We place an upper limit of 65 radio transients above 6 mJy over the entire sky (95% confidence level). The implications are as follows. First, we derive a limit on the typical beaming of GRBs; we find f ≳ 60, ~5 times higher than our earlier results [f ≡ (θ/2)-1]. Second, our results impose an upper limit on the rate of events that eject ≳1051 ergs in unconfined relativistic ejecta, whether or not accompanied by detectable emission in wavebands other than the radio. Our estimated rate, ≤ 1000 yr-1 Gpc-1, is about 2 orders of magnitude smaller than the rate of core-collapse SNe (and Type Ib/c events in particular), indicating that only a minority of such events eject significant amounts of relativistic material, which are required by fireball models of long-soft GRBs. Finally, we show that wider and/or deeper radio variability surveys are expected to detect numerous orphan radio GRB afterglows and illustrate the great potential of new radio instruments to revolutionize the study of nearby SNe.
Modeling and Prediction of Integrated Passive Device Filter Based on Artificial Neural Network

This paper presents a modeling and prediction method of integrated passive device (IPD) filters based on the artificial neural network (ANN) model. The ANN forward model is trained to directly generate the distribution of poles and residues of the filter under a group of geometric parameters, while the ANN inverse model is established to generate the geometric dimensions with the poles and residues. The effectiveness of the proposed method is verified by the comparison among the ANN predicted, circuit and full-wave simulated frequency responses. The design of such an IPD filter can be simplified significantly.
TAUVEX - UV Space Telescope

The TAUVEX UV Space Telescope currently under construction by El-Op Ltd. in Israel is designed both for recording images of the sky in the UV region and to serve as the optical monitor for the SODART X-Ray Telescope being built by the Danish Space Research Institute. The two systems, together with several other experiments, will be flown on the S-R-G satellite to be launched by the CIS in 1995. TAUVEX will image a field of about 1 deg simultaneously in three spectral bands. In addition, it will record a selected object in a high-speed time-resolved mode in these bands. The concept and design of TAUVEX is described in this paper.
Specific heat of europium sulphide: a comparison between theory and experiment

It is suggested that the exponent α for the specific heat of the classical Heisenberg model is -fraction one-sixteens. A closed-form expression is derived to represent the specific heat in the range T > Tc. Good agreement is obtained with experimental data on europium sulphide. It is concluded that the finite limitation of the specific heat observed experimentally is not due to the Heisenberg interaction.
Tunable absorption resonance in electromechanical one-dimensional metallodielectric photonic band gap structures

We present the results of an experimental study of an electromechanical, one-dimensional, metallodielectric photonic band gap structure. We monitor the reflectance as a function of the thickness of an air gap located inside the stack. The results suggest that, by changing the thickness of the air gap by approximately 20 nm, a large contrast can be achieved between high- and low-reflectance states, as reflectance switches from a fraction of a percent to about 70%. Using this approach, we are able to selectively remove a relatively narrow but tunable wavelength range from the reflected spectrum, thus making possible applications to accelerometers, linear optical switches, modulators, and other specialized filters in the visible range. The characteristic absorption spectrum can be controlled by varying air gap and dielectric layer thicknesses.
A Time Domain Neural Network Method for Scattering of Complex Scatterers

To establish an efficient and high accuracy neural network-based time-domain electromagnetic calculation method, a supervised learning method based on a long short-term memory (LSTM) network is proposed in this work to obtain the time-domain electromagnetic response of scatterers. Based on the propagation direction of electromagnetic waves, the permittivity distribution of scatterers is input into each LSTM cell in turn in this method. To validate the proposed method, the complex scatterers with irregular shape and inhomogeneous permittivity are considered. After training, the results show that the LSTM network can well complete the prediction of time-domain scattering response with high accuracy in the calculation of two-dimensional complex scatterers and a relative error is only 1.3%, while in terms of efficiency, it is more than 400 times faster than the finite-difference time-domain (FDTD) method.
Parity violation effects in diatomics

Discussion of the parity violation and the break of the time-reversal invariance in diatomic molecules has continued for a number of years. Experiments on the TlF molecule gave one of the most stringent limits on the electric-dipole moment of the proton and on the T-violating nuclear forces. At present, a new generation of experiments with paramagnetic diatomic molecules is underway. These experiments are aimed mainly at the search for the electric-dipole moment of the electron. In this topical review we examine theoretical aspects of parity non-conservation in diatomic molecules. We focus on molecular theory leaving aside the nuclear part of the problem. In this approach the nucleus is characterized by the number of P-odd and P,T-odd moments, namely anapole moment, Schiff moment and magnetic quadrupole moment. Molecular theory has to link these moments to the experimentally measured quantities, such as frequency shifts, etc. The other possible sources of the parity non-conservation in molecules are the electron-nuclear neutral current interactions and the electric-dipole moment of the electron. They are also discussed in this review.
Event-triggered dynamic output feedback control for networked control systems

This study is concerned with the event-triggered control for networked control systems via dynamic output feedback controllers (DOFCs). The output measurement signals of the physical plant are sampled periodically. An output-based discrete event-triggering mechanism is introduced to choose those only necessary sampled-data packets to be transmitted through a communication network for controller design. Under this event-triggering mechanism, the resultant closed-loop system is first modelled as a linear system with an interval time-varying delay. Then a novel stability criterion is established by employing the Lyapunov-Krasovskii functional approach. Based on this stability criterion, a new sufficient condition is derived to co-design both the desired DOFCs and the event-triggering parameters. Finally, a satellite control system is taken to show the effectiveness of the proposed method.
Direct measurement of the impulse in a magnetic thrust chamber system for laser fusion rocket

An experiment is conducted to measure an impulse for demonstrating a magnetic thrust chamber system for laser fusion rocket. The impulse is produced by the interaction between plasma and magnetic field. In the experiment, the system consists of plasma and neodymium permanent magnets. The plasma is created by a single-beam laser aiming at a polystyrene spherical target. The impulse is 1.5 to 2.2 μNs by means of a pendulum thrust stand, when the laser energy is 0.7 J. Without magnetic field, the measured impulse is found to be zero. These results indicate that the system for generating impulse is working.
DUALIZABILITY OF GRAPHS

Abstract We investigate natural dualities for classes of simple graphs. For example, we give a natural duality for the class consisting of all n-colourable graphs and show that, for all n≥3, there is no natural duality for the class consisting of all freely n-colourable graphs. We also prove that there exist arbitrarily long finite chains of 3-colourable graphs that alternate between being dualizable and nondualizable.
Optical parametric generation of high-energy femtosecond pulses in the 1-3 &mgr;m spectral range using BiB3O6

We analyze the phase-matching properties of the monoclinic nonlinear crystal BiB3O6 (BIBO) for optical parametric amplification of femtosecond pulses when pumped near 800 nm by Ti:sapphire based laser systems. BIBO possesses higher figure of merit than &bgr;-BaB2O4 (BBO) and extremely large parametric gain bandwidth for collinear interaction. Experimentally, we compare type-II BIBO and BBO in a double pass optical parametric amplifier (OPA), pumping by amplified 80-fs pulses near 800 nm at a repetition rate of 1 kHz. The conversion efficiency obtained with BIBO is higher and a total energy output (signal + idler) of about 80 &mgr;J is obtained in the plateau region of the tunability curve (1-3 &mgr;m) with an uncoated sample, for a total pump energy of 375 &mgr;J. Shorter pulse durations were obtained with BIBO: e.g. 120 fs (FWHM) near 3 &mgr;m for the idler pulses. Substantial power scaling of such a femtosecond OPA is possible using a large aperture BIBO crystal in the second stage and we demonstrate a total energy output (signal + idler) exceeding 1 mJ, corresponding to an intrinsic conversion efficiency of ≈32% for the second stage, using a specially designed high-power Ti:sapphire pump system operating at 1 kHz. The tunability extends in this case from 1.1 to 2.9 &mgr;m. The high parametric gain and broad amplification bandwidth of type-I BIBO allow the maintenance of the pump pulse duration, leading to pulse lengths less than 140 fs, both for the signal and idler pulses, even at such high output levels.
Limit behaviour of large Frobenius numbers

This is an investigation of the problem of the asymptotic distribution of the Frobenius numbers of relatively prime integers. For virtually definitive results are obtained. For 3$ SRC=http://ej.iop. org/images/0036-0279/62/4/R03/tex_rm_4429_img3. gif/> it is shown that the distributions appearing form a compact set. An essential role is played by the limit theorem for logarithms of denominators of continued fractions of random numbers.
Optical and topographic changes in water-responsive patterned cholesteric liquid crystalline polymer coatings

In this work, we present patterned water-responsive coatings, which alter both their topological and optical properties. The polymer coatings are based on a hydrogen-bonded cholesteric liquid crystalline polymer network. A two-step photopolymerization procedure leads to a patterned coating with repeating liquid crystalline and isotropic areas. The cholesteric liquid crystalline areas reflect green light, whilst the isotropic areas are transparent for visible light. Treatment with alkaline solution results in a hygroscopic polymer salt coating. When placed in demineralized water, the polymer films swells, leading to an enhancement of the surface topography structure in which the liquid crystalline areas swell more. Moreover, the pitch of the helical organization in the cholesteric areas increases due to this swelling leading to a color change from green to red.
Keypoint Recognition for 3D Head Model Using Geometry Image

This paper presents a novel and efficient 3D head model keypoint recognition framework based on the geometry image. Based on conformal mapping and diffusion scale space, our method can utilize the SIFT method to extract and describe the keypoint of 3D head model. We use this framework to identify the keypoint of the human head. The experiments shows the robust and efficiency of our method.