Miracle-dz/UniFAR-FTUs huggingface dataset:
Stellar kinematics in the galactic centre

The observations of the stellar kinematics in the central 8 pc of the Galaxy are presented. It is shown that the spectroscopy of the 2.3 microns CO absorption feature, in late type stars, yields the stellar velocity dispersion and the average stellar radial velocity as a function of galactocentric distance. A sample spectra that illustrates the observed velocity shifrs and velocity dispersion is given. The analysis shows that the velocity dispersion of the stars is large, and that it dominates the stellar kinematics. The use of these kinematic data, to probe the mass distribution in the Galactic center, is considered.
Simulation, eigenmode analysis, and tolerancing for stable laser resonators

Recently the importance of numerical simulations for the design of laser resonators has grown considerably. This applies in particular if the alignment of components within the resonator is crucial for its stability. In such cases a tolerance analysis is required that can be done most efficiently using numerical simulation tools. In this paper, we introduce a computer model for resonators based on components and their combination using absolute or relative positioning. We show that this approach is the basis for tolerancing and sensitivity analysis. Further we discuss the concepts of field tracing and unified optical modeling that allow the coupling of several propagation methods within one modeling task. For laser resonators this involves in particular free space propagation methods as the Fresnel integral, geometrical optics and split step beam propagation methods. The primary goal is to provide a fully vectorial simulation as accurate as required and as fast as possible. This approach covers in particular general eigenmode models and general geometries including micro-structured surfaces that can be used for additional beam control as it is shown in the examples.
Testing parameterization schemes for simulating depositional growth of ice crystal using Koenig and Takahashi parameters: a pre‐summer rainfall case study over Southern China

In this study, the three (Hsie, Krueger and Zeng) schemes that parameterize depositional growth of ice crystal are tested using Koenig and Takahashi parameters in modeling China pre‐summer torrential rainfall event. The Krueger scheme with the Takahashi parameter produces the closest simulations to the observations because it increases cloud ice and snow in the upper troposphere. The increased ice hydrometeor enhances and suppresses infrared radiative cooling above and below 12 km, respectively. The suppressed infrared cooling reduces net condensation while the enhanced infrared cooling suppresses hydrometeor loss through the reduction in melting of ice hydrometeor.
Increasing the dynamic range of synthetic aperture vector flow imaging

In current ultrasound systems the dynamic range of detectable velocities is susceptible to the selected pulse repetition frequency, thus limiting the dynamic range of flow mapping. To establish the feasibility of extending the range of detectable velocities towards low velocity vessels, results are presented using synthetic aperture which increases the frame-to-frame signal correlation of the scatterer displacement while providing continuous data. In this paper, recursive synthetic aperture acquisition, directional beamforming, and cross-correlation are used to produce B-mode and vector velocity images. The emissions for the two imaging modes are interleaved 1-to-1 ratio, providing a high frame rate equal to the effective pulse repetition frequency of each imaging mode. The direction of the flow is estimated, and the velocity is then determined in that direction. This method works for all angles, including fully axial and transverse flows. The method is investigated using Field II simulations and data from the experimental ultrasound scanner SARUS, acquired from a circulating flow rig with a parabolic flow. A 7 MHz linear array transducer is used, and several pulse repetition frequencies are synthesized in a simulated flow phantom with linearly increasing velocity and in a dual-vessel phantom with laminar flow with peak velocities of 0.05 m/s and 0.5 m/s. The experimental measurements are made with laminar flow as in the simulations. For the simulated and experimental vessel with peak velocity of 0.05 m/s and flow angle of 75°, the relative bias is -0.29% and -3.19%, and the relative standard deviations are 2.39% and 5.75% respectively. For the simulated and experimental vessel with peak velocity of 0.5 m/s and flow angle of -90°, the relative biases are -4.30% and -7.37%, and the relative standard deviations are 1.59% and 6.12%, respectively. The presented method can improve the estimates by synthesizing a lower pulse repetition frequency, thereby increasing the dynamic range of the vector velocity imaging.
Monochromatic Green Light Stimulation during Incubation Alters Hepatic Glucose Metabolism That Improves Embryonic Development in Yangzhou Goose Eggs

The influence of monochromatic green light stimulation on hatching performance and embryo development has been studied in chickens, but not geese. The liver has crucial functions in the regulation of energy metabolism during embryogenesis, but its involvement in green light transduction is still unidentified. We aimed to determine the influence of monochromatic green light on Yangzhou goose hatching performance and embryo development. We also investigated the metabolomics and transcriptomic responses of the embryonic liver to green light to determine the underlying molecular mechanisms. Eggs were incubated under either 12 h of monochromatic green light/dark (12 L:12D) cycles or 24 h of darkness (0G:24D). Green light promoted embryonic development and hatching performance, also affected the expression of myogenic regulatory factors associated with muscle development. It also shortened hatching time and elevated plasma levels of growth hormone and insulin-like growth factor-1. Metabolomics and transcriptomic results revealed differentially expressed genes and metabolites with enhanced gluconeogenesis/glycolysis and increased plasma glucose and pyruvate levels under green light. Hence, the growth-promoting effect possibly through regulating energy metabolism in the liver and myogenic regulatory factors in muscle. Our findings provide important and novel insights into the mechanisms underlying the beneficial effects of green light on goose embryos.
Non-bandgap defect modes in the photoresponse of mid-IR photonic crystal detectors

Non-bandgap defect modes, defect modes showing up in photonic crystal (PhC) structures which do not exhibit a complete photonic bandgap, are investigated experimentally by means of a QWIP (quantum well intersubband photodetector) incorporated within a two-dimensional (2D) triangular photonic crystal of air holes. The modes appear as a local enhancement in the photocurrent spectrum due to an increased in-coupling of surface incident light when a defect mode is present. Such delocalized non-bandgap defect modes and the influence of the entire PhC on their energetic positions are experimentally determined and show good agreement with (2D as well as three-dimensional (3D)) simulations.
Enhanced photosensitivity of electro-oxidized epitaxial graphene

We report the enhanced photosensitivity of epitaxial graphene (EG) after electrochemical oxidation in nitric acid. The onset of photoconductivity appears at a photon energy of ∼1.7 eV while the responsivity reaches 2.5 A/W at a wavelength of 470 nm (blue light, energy 2.64 eV) and further increases to 200 A/W in the UV spectral range (3.5 eV, 350 nm). The observed photoresponse is attributed to the formation of deep traps at the electro-oxidized EG interface, which release charge carriers under illumination and prolong the life time of the photocarriers. Potential applications of electro-oxidized EG in ultraviolet photodetection are discussed.
Removal of impulse noise from highly corrupted images by using noise position information and directional information of image

In this paper, a new progressive switching type filter is proposed in order to restore images corrupted by salt-pepper impulse noise. The algorithm consists of two main processes: 1) noise detection - an impulse detection algorithm is used before filtering, a noise position image is obtained and 2) noise filtering - disturbed pixels are only filtered by using the noise position image. In this paper, we study the second process (i.e., noise filtering). In the past, the median filter is used for the second process. In this paper, we introduce a weighted average (WA) filter into second process. Using the directional property of input images derives the weights of the WA filter. Therefore, better restoration results are expected. Simulation results demonstrate that the proposed method is superior to the conventional filters which used the median filter in the second process.
The rôle of planetary waves in the formation of polar stratospheric clouds

Several recent works attribute the formation of polar stratospheric clouds (PSCs) to the occurrence of localized orographic waves. Using ECMWF analyses, we investigate the large scale stratospheric flow conditions in a number of cases where PSCs have been detected, both in the Arctic and in the Antarctic. We show that PSCs appear within strong planetary scale uplifts of isentropic surfaces. The adiabatic cooling of air parcels travelling within such planetary scale uplifts while conserving their humidity and trace constituents, seems to be the main mechanism for PSC formation. The PSC distribution would then follow a planetary structure, even though local orographic waves could still play an additional role when planetary scale conditions are met.
SPIRAL STRUCTURE OF M51 - DISPLACEMENT OF THE H-I FROM THE NONTHERMAL RADIO ARMS

The Westerbork Synthesis Radio Telescope has been used to observe H I in the spiral galaxy M 51 at 12 x 18 arcsec resolution; the results thus obtained have been compared with the dust lane, H II-region, and nonthermal continuum emission tracers of spiral structure. The displacement of the H I arms from the region of maximum interstellar gas compression is confirmed to be more than an isolated peculiarity of a particular galaxy. The observations are simply characterized within a framework of density-wave streaming of the interstellar gas. 11 refs.
TRANSIENT SOUND FIELDS FROM IMPACTED PLATES: COMPARISON BETWEEN NUMERICAL SIMULATIONS AND EXPERIMENTS

A comparison between measured and simulated transient acoustic fields generated by a thin rectangular impacted steel plate is reported. The plate vibration is modelled in the time domain using a finite difference scheme of second-order in time and fourth-order in space (2-4 scheme) and the radiated acoustic pressure is obtained by solving numerically the Rayleigh integral equation by using a simple Boundary Element Method (trapezoidal rule). The simulated results are evaluated in the form of the spatial pressure distribution at times short-after the impact excitation. The measurements are performed using an optical method: pulsed two-reference-beam holographic interferometry. Results in the form of 2-D projections of the acoustic pressure field are obtained and compared with the simulations. A high degree of similarity is found between the measured and simulated sound fields.
Applied Spatial Statistics for Public Health Data

This book is a welcome addition to the growing literature on spatial statistics, with the distinctive feature that it is aimed at “the intersection of at least three traditionally separate academic disciplines: statistics, epidemiology and geography” (p. 4). Spatial statistics is a subject with a fascinating history. From a theoretical perspective, the core of the subject is the formulation and analysis of stochastic processes indexed by (typically two-dimensional) space rather than by one-dimensional time, in which context the increase in dimensionality is less important than the loss of a natural ordering to the index set. My favorite teaching example of this point, which has its origins in an article by Brook (1964), is the following. Consider the first-order temporal autoregressive process Yt , conventionally defined as Yt = αYt−1 + Zt , (1)
Ion‐temperature‐gradient‐driven modes in neoclassical regime

A reduced set of neoclassical fluid equations, consisting of the parallel ion flow velocity v∥, the generalized potential F, the ion pressure p, and the parallel ion heat flow q∥, is derived. The resultant equations are the extension of reduced fluid equations derived from Braginskii equations with the high collisionality to the equations relevant to a fusion plasma with low to intermediate collisionality. The linear ηi mode dynamics is reinvestigated by using the resultant model equations. The effects of the perpendicular compressibility in the ion pressure response, the parallel heat flow, and the neoclassical viscosity are analyzed both analytically and numerically. It is stressed that the closure condition of neoclassical viscosity changes the sign of energy dissipation and seriously affects the stability of ηi modes.
A real‐time pitch extraction and four‐tone recognition system for mandarin speech

Abstract Mandarin is a type of tone language, i. e. , the tones are part of the phonemic make‐up of words (1). Basically, there are four tones in Mandarin. On the basis of the fact that the four individual tones in Mandarin have almost fixed patterns on their pitch variations, we have designed a real‐time, speaker‐independent pitch extraction and four‐tone recognition system for isolated Mandarin speech: The pitch periods are extracted from the zero‐crossing interval sequence of speech; and the recognition algorithm is derived from the analysis of pitch contours of the four tones. The system has been implemented on a microcomputer development system MDS‐286. The average four‐tone recognition rate for the digits “0” to “9”, uttered 10 times by 5 males and 5 females, is 90.2%. The response time is about 1.64s for one digit. Both the recognition rate and the response time can be further improved.
WDM backbone network with guaranteed performance planning

Wavelength-Division multiplexing (WDM), which allows a single fibre to carry multiple signals simultaneously, has been widely used to increase link capacity and is a promising technology in backbone transport network. But designing such WDM backbone network is hard for two reasons, one is the uncertainty of future traffic demand, the other is difficulty of planning of the backup resource for failure conditions. As a result, enormous amount of link capacity for the network has to be provided for the network. Recently, a new approach called Valiant Load-Balanced Scheme (VLBS) has been proposed to design the WDM backbone network. The network planned by Valiant Load-Balanced Scheme is insensitive to the traffic and continues to guarantee performance under a user defined number of link or node failures. In this paper, the Valiant Load-Balanced Scheme (VLBS) for backbone network planning has been studied and a new Valiant Load-Balanced Scheme has been proposed. Compared with the early work, the new Valiant Load-Balanced Scheme is much more general and can be used for the computation of the link capacity of both homogeneous and heterogeneous networks. The abbreviation for the general Valiant Load-Balanced Scheme is GVLBS. After a brief description of the VLBS, we will give the detail derivation of the GVLBS. The central concept of the derivation of GVLBS is transforming the heterogeneous network into a homogeneous network, and taking advantage of VLBS to get GVLBS. Such transformation process is described and the derivation and analysis of GVLBS for link capacity under normal and failure conditions is also given. The numerical results show that GVLBS can compute the minimum link capacity required for the heterogeneous backbone network under different conditions (normal or failure).
Dictionary learning based low-dose x-ray CT reconstruction using a balancing principle

The high utility and wide applicability of x-ray imaging has led to a rapidly increased number of CT scans over the past years, and at the same time an elevated public concern on the potential risk of x-ray radiation to patients. Hence, a hot topic is how to minimize x-ray dose while maintaining the image quality. The low-dose CT strategies include modulation of x-ray flux and minimization of dataset size. However, these methods will produce noisy and insufficient projection data, which represents a great challenge to image reconstruction. Our team has been working to combine statistical iterative methods and advanced image processing techniques, especially dictionary learning, and have produced excellent preliminary results. In this paper, we report recent progress in dictionary learning based low-dose CT reconstruction, and discuss the selection of regularization parameters that are crucial for the algorithmic optimization. The key idea is to use a “balancing principle” based on a model function to choose the regularization parameters during the iterative process, and to determine a weight factor empirically for address the noise level in the projection domain. Numerical and experimental results demonstrate the merits of our proposed reconstruction approach.
Minimum-time trajectory planning of mechanical manipulators under dynamic constraints

The paper presents a global optimization approach to the trajectory planning problem of mechanical manipulators. The purpose is to obtain a minimum-time cubic spline trajectory subject to constraints given by limited joint torques and torque derivatives taking into account the non-linear manipulator dynamics. It is shown how, without conservativeness, a semi-infinite optimization problem emerges. Conditions ensuring that the formalized problem admits a solution are given. The estimated global solution can be actually obtained by means of an hybrid genetic/interval algorithm that guarantees the feasibility of the found solution. The methodology is illustrated with numerical details for a two-link planar arm and a PUMA six-link manipulator; for the former, comparisons with an alternative optimization solver are exposed.
Effects of Doping Profile on Characteristics of InAs Quantum Dots

Capacitance-voltage measurements were carried out to investigate the effects of the doping profile on characteristics of self-assembled InAs quantum dots. Using this technique, we observed features of zero-dimensional electron confinement indicating the presence of quantum dots. However, the number of confined states differed depending on the doping profile, and this fact was confirmed by photoluminescence measurements. The equation in the depletion approximation led us to calculate the distribution of carriers as a function of depth from the sample surface, and the results are in agreement with the depth of the quantum dot layer.
A flexible model for the evaluation of soft conditional preferences in fuzzy databases

In this paper, we model the evaluation of soft conditional preferences in flexibly querying fuzzy databases. We assume that soft conditional preferences are expressed in the form “If C then Q1 is better than Q2,” where C is the primary condition, and Q1, Q2 are the conditions with preferences. They are fuzzy predicates, which represent soft constraints admitting satisfaction degrees. The satisfaction degree of C tunes the preference of Q1 over Q2, so that as it increases also the preference of Q1 increases with respect to Q2. When C is not satisfied at all there is no preference between Q1 and Q2. The basic idea of the proposed model is to compute the preference degree of Q1 with respect to Q2 depending on the degree of satisfaction of C, and to use this value to modify the evaluation function of the soft conditions Q1 and Q2. This way we fuse in a single step the evaluations of both the selection conditions and their preference, which are the two subsequent phases necessary for evaluating queries with preferences in fuzzy databases. Specifically, the preference degree is used to relax the soft constraint imposed by the evaluation function of the most preferred condition Q1 as well as to restrict the evaluation function of the less preferred condition Q2. The more a soft condition is preferred, the more its evaluation function becomes tolerant to undersatisfaction; similarly, the less a condition is preferred the more its evaluation function is restricted so as to make more difficult its satisfaction. © 2008 Wiley Periodicals, Inc.
Spectroscopic rotating compensator ellipsometry in the infrared: retarder design and measurement

Rotating compensator ellipsometry (RCE) is an approach to ellipsometry that is superior to the widely used rotating analyser ellipsometry (RAE). An essential component in RCE is a retarder that generates a retardance close to . In contrast to RCE at a single wavelength, spectroscopic RCE requires a retarder that performs well over a wide range of the used spectrum. The designed retarder is capable of this and works on the principle of total internal reflection. Making use of this retarder, RCE is tested by measuring the optical characteristics of a Teflon-like layer on an aluminium substrate. The results show good agreement with similar RAE measurements, as well as data calculated from an ellipsometric model.
Gesture Recognition Based on Detection of Periodic Motion

In this paper, we propose a method to recognize periodic gestures from images. The proposed method uses a amplitude spectrum and a phase spectrum that are obtained by applying Fast Fourier Transform (FFT) to a time series of intensity images. FFT is applied to each pixel of low-resolution images. The method consists of 2 steps. First, the method detects periodic motion regions from the amplitude spectrum. Secondly, the method uses the phase spectrum in the detected periodic motion region to classify the gestures. The proposed method is robust to lighting conditions and individual differences in skin color because it does not rely on color information. Additionally, the proposed method is possible to recognize periodic gestures when multiple target regions, for example, two or more individuals are observed. Several experiments are performed to demonstrate the effectiveness of the proposed method.
Correspondence principle in free-electron lasers

Multiphoton interaction in free-electron lasers is studied using the correspondence principle. The developed theory is applicable to both quantum-mechanical and classical regimes of operation of the laser. The suggested formalism simplifies the traditional calculation of the small-signal, single-particle gain in the system. As an example, the theory is applied to the case of the free-electron laser operating in combined transverse helical and axial guide magnetic fields. 17 references.
Multidimensional Limit Theorems Allowing Large Deviations for Densities of Regular Variation

The sums of i.i. d. random vectors are considered. It is assumed that the underlying distribution is absolutely continuous and its density possesses the property which can be referred to as regular variation. The asymptotic expressions for the probability of large deviations are established in the case of a normal limiting law. Furthermore, the role of the maximal summand is emphasized.