Miracle-dz/UniFAR-FTUs huggingface dataset:
Fast object detection in compressed JPEG Images

Object detection in still images has drawn a lot of attention over past few years, and with the advent of Deep Learning impressive performances have been achieved with numerous industrial applications. Most of these deep learning models rely on RGB images to localize and identify objects in the image. However in some application scenarii, images are compressed either for storage savings or fast transmission. Therefore a time consuming image decompression step is compulsory in order to apply the aforementioned deep models. To alleviate this drawback, we propose a fast deep architecture for object detection in JPEG images, one of the most widespread compression format. We train a neural network to detect objects based on the blockwise DCT (discrete cosine transform) coefficients issued from the JPEG compression algorithm. We modify the well-known Single Shot multibox Detector (SSD) by replacing its first layers with one convolutional layer dedicated to process the DCT inputs. Experimental evaluations on PASCAL VOC and industrial dataset comprising images of road traffic surveillance show that the model is about 2× faster than regular SSD with promising detection performances. To the best of our knowledge, this paper is the first to address detection in compressed JPEG images.
Investigating Concurrency in Online Auctions Through Visualization

This article presents graphical techniques for visualizing concurrency in online auctions. These include rug plots, which allow for a compact view of many simultaneous auctions while preserving the structure of individual auctions. We also use box plots, moving statistics plots, and autocorrelation plots, supplemented by statistical tests. Together, these are used to study synchronous events and to surmise trends in the data, as well as to raise new research questions. We illustrate our methods on data from eBay.com.
Tunneling of holes is observed by second-harmonic generation

Al2O3 passivated n-doped Si substrates are investigated by second-harmonic generation (SHG) upon applying an external electric field by a corona wire. The observed change in the SHG response upon applying an external electric field is attributed to charge transfer in the semiconductor. Capacitance-voltage measurements are performed to affirm this conclusion. Upon applying a large negative electric field over the structure, a clear alteration in SHG signal is observed, which corresponds to tunneling of holes from the n-doped silicon into the aluminum oxide layer.
Continuous wave optical spectroscopic system for use in magnetic resonance imaging scanners for the measurement of changes in hemoglobin oxygenation states in humans

A continuous wave near infrared three-wavelength laser diode spectroscopic (NIRS) system designed for use in magnetic resonance imaging (MRI) scanners is described. This system measures in vivo changes in the concentrations of oxyhemoglobin (HbO) and deoxyhemoglobin (Hb) in humans. An algorithm is implemented to map changes in light intensity to changes in the concentrations of Hb and HbO. The system’s signal to noise ratio is 3.4×103 per wavelength on an intralipid phantom with 10 Hz resolution. To demonstrate the system’s performance in vivo, data taken on the human forearm during arterial occlusion, as well as data taken on the forehead during extended breath holds, are presented. The results show that the instrument is an extremely sensitive detector of hemodynamic changes in human tissue at high temporal resolution. NIRS directly measures changes in the concentrations of hemoglobin species. For this reason, NIRS will be useful in determining the sources of MRI signal changes in the body due to hemody.
Change of Synoptic Climatology Associated with the Variation of Summer Rainfall Amount over the Korean Peninsula Around 1993/1994

In this study, an investigation has been carried out to understand 1) temporal variation of rainfall amount in summer over south Korea during the 30-year period of 1979-2008 and 2) the relationship between the variation of rainfall amount and the change of large-scale monsoon circulation around 1993/1994 over East Asia. The analysis of rainfall amount is carried out separately for whole summer (June-August), climatological Changma period of 23 June-23 July, and August to consider variations within summer. To relate the variation of rainfall amount with the change of large-scale circulation, we have considered two 15-year periods of 1979-1993 and 1994-2008. This study has used observations at 58 stations in South Korea and NCEP-NCAR reanalysis data. The major change in synoptic environment for the Changma period is characterized by the intensified anticyclone over Mongolia during 1994-2008, which results in a weak meridional oscillation of Changma front. As a result, rainfall amount for the Changma period and the frequency of extreme events have significantly increased after 1993/1994. A major change of synoptic environment for August is the significant westward extension of the western Pacific subtropical high, which allows not only more moisture transports but also stronger cyclonic circulation over the Korean peninsula. Rainfall amount for August and frequency of extreme events have also increased after 1993/1994. However, variability of rainfall amount is larger for August than that for the Changma period, with some years showing very dry August (monthly rainfall amount less than 150 mm).
Estimation of Time Delay Using Conventional Beamforming-based Algorithm for UWB Systems

In this paper, Conventional Beamforming algorithm is applied to the estimation of the time delay in impulse radio UWB (Ultra-Wide-Band) systems. The performance of the proposed algorithm is evaluated in indoor UWB channel model (CM1, CM2, CM3, and CM4) with dense multi-path. The simulation results show that the performance of the proposed algorithm is better than that of the correlation-based time delay estimation method. RMS error is used as a performance criterion.
Optical coherence tomography-based angle-resolved backscattering studies on bovine tendon and cartilage

The difference in the genetic make up of the constituent molecules in collagen fibers in tendon and articular cartilage is what makes them mechanically and functionally different. A comparative study carried out on the differences in the angle-resolved back-scattering properties obtained from optical coherence tomography based studies on the two different types of scatterers: collagen I and collagen II fibers in bovine tendon and bovine articular cartilage sample, respectively, is reported here. Tendon sample shows greater anisotropy in the angle-resolved scattering profile compared to that obtained from articular cartilage sample. Rayleigh-Gans scattering approximation is used to provide the qualitative support needed to substantiate differences in the light scattering profiles obtained from the two tissues based on the size and type of the scatterers involved.
Global Asymptotic Stability in Some Discrete Dynamical Systems

For a discrete dynamical system xn + 1 = Txn on M ⊂ Rr some general conditions will be specified under which the unique equilibrium is globally asymptotically stable. As a special result we obtain the strong negative feedback property established in A. M. Amleh, N. Kruse, and G. Ladas (J. Differ. Equations Appl. to appear). Finally we apply our result to show that the equilibrium x* = 1 of the Putnam difference equation,xn+1=xn+xn−1+xn−2xn−3xnxn−1+xn−2+xn−3,with positive initial conditions x0,…,x − 3 is globally asymptotically stable.
InGaN-Based Multi-Quantum-Well-Structure Laser Diodes

InGaN multi-quantum-well (MQW) structure laser diodes (LDs) fabricated from III-V nitride materials were grown by metalorganic chemical vapor deposition on sapphire substrates. The mirror facet for a laser cavity was formed by etching of III-V nitride films without cleaving. As an active layer, the InGaN MQW structure was used. The InGaN MQW LDs produced 215 mW at a forward current of 2.3 A, with a sharp peak of light output at 417 nm that had a full width at half-maximum of 1.6 nm under the pulsed current injection at room temperature. The laser threshold current density was 4 kA/cm2. The emission wavelength is the shortest one ever generated by a semiconductor laser diode.
A Novel Network Planning Algorithm of Three-Dimensional Dense Networks Based on Adaptive Variable-Length Particle Swarm Optimization

Small base stations (SBSs) deployed in hotspots are formed into dense networks to improve network coverage and system capacity. However, the deployment of SBSs becomes a great challenge owing to the high density of small cells and the uneven distribution of traffic. In this paper, we propose a three-dimensional (3D) dense network planning method to deploy SBSs in hotspots. First, considering the propagation characteristics of 3D indoor deployment environment and the hybrid distribution of traffic, we estimate the network dimension to obtain the approximate number of SBSs that need to cover the entire area and meet the rate requirements of all users in a given space. Then, we formulate network planning as an optimization problem with the objective of minimizing the number of SBSs while satisfying both coverage and capacity constraints. Finally, in order to solve the optimization problem, we propose an adaptive variable-length particle swarm optimization (AVLPSO) algorithm. Simulation results indicate that compared with the traditional algorithms, the proposed algorithm can significantly achieve higher service ratio and reduce the costs of deployment.
DE RHAM–WITT COHOMOLOGY FOR A PROPER AND SMOOTH MORPHISM

We construct a relative de Rham–Witt complex $W\varOmega^{\cdot}_{X/S}$ for a scheme $X$ over a base scheme $S$. It coincides with the complex defined by Illusie (Annls Sci. Ec. Norm. Super.12 (1979), 501–661) if $S$ is a perfect scheme of characteristic $p>0$. The hypercohomology of $W\varOmega^{\cdot}_{X/S}$ is compared to the crystalline cohomology if $X$ is smooth over $S$ and $p$ is nilpotent on $S$. We obtain the structure of a $3n$-display on the first crystalline cohomology group if $X$ is proper and smooth over $S$. AMS 2000 Mathematics subject classification: Primary 14F30; 14F40
Atomistic simulations of the mechanical properties of silicon carbide nanowires

Molecular dynamics methods using the Tersoff bond-order potential are performed to study the nanomechanical behavior of [111]-oriented β-SiC nanowires under tension, compression, torsion, combined tension-torsion and combined compression-torsion. Under axial tensile strain, the bonds of the nanowires are just stretched before the failure of nanowires by bond breakage. The failure behavior is found to depend on size and temperatures. Under axial compressive strain, the collapse of the SiC nanowires by yielding or column buckling mode depends on the length and diameters of the nanowires, and the latter is consistent with the analysis of equivalent continuum structures using Euler buckling theory. The nanowires collapse through a phase transformation from crystal to amorphous structure in several atomic layers under torsion strain. Under combined loading the failure and buckling modes are not affected by the torsion with a small torsion rate, but the critical stress decreases with increasing the torsion rate. Torsion buckling occurs before the failure and buckling with a big torsion rate. Plastic deformation appears in the buckling zone with further increasing the combined loading.
On the construction of related differential equations

in which X is a parameter whose absolute value is large, and the coefficients pi(z, X) are either functions of z alone, or series in powers of 1/X with coefficients that are functions of z. The forms of the solutions of such an equation, as they depend asymptotically upon X in a given region of the variable z, are known to be determined in large measure, though not entirely, by the configuration of the roots of the auxiliary algebraic equation
Performance of Some New Ridge Regression Estimators

Abstract In the ridge regression analysis, the estimation of ridge parameter k is an important problem. Many methods are available for estimating such a parameter. This article has considered some of these methods and also proposed some new estimators based on generalized ridge regression approach. A simulation study has been made to evaluate the performance of proposed estimators based on the minimum mean squared error (MSE) criterion. The simulation study indicates that under certain conditions the proposed estimators perform well compared to least squares estimators (LSE) and other popular existing estimators. Finally, a numerical example has been analyzed and its findings support the simulation results to some extent.
Proximity effect for asymmetrical three-layered F/S structures in external magnetic field

We study the critical temperature Tc of the three-layered ferromagnet/superconductor (F/S) structures in the external magnetic field H parallel to the film. For the F1/S/F2 and F1/F2/S asymmetrical trilayers, the triplet superconducting component is generated at noncollinear magnetizations of the F layers. Assuming that all S and F layers are dirty, we solve boundary problem for the Usadel function. The results of numerical calculations for Tc as function thicknesses both F1 and F2 layers at various parameters F/S structure are presented. The application to the spin-switch problem is discussed. We found that asymmetry can essentially change the spin-switch observation condition. The re-entrant superconductivity caused by external magnetic field is predicted for the F1/F2/S trilayer.
The Sensitivity of Rainfall Estimation to Error Assumptions in a Bayesian Passive Microwave Retrieval Algorithm

AbstractThe Goddard profiling algorithm (GPROF) uses Bayesian probability theory to retrieve rainfall over the global oceans. A critical component of GPROF and most Bayes theorem–based retrieval frameworks is the specification of uncertainty in the observations being utilized to retrieve the parameter of interest. In the case of GPROF, for any sensor, uncertainties in microwave brightness temperatures (Tbs) arise from radiative transfer model errors, satellite sensor noise and/or degradation, and nonlinear, scene-dependent Tb offsets added during sensor intercalibration procedures. All mentioned sources impact sensors in a varying fashion, in part because of sensor-dependent fields of view. It is found that small errors in assumed Tb uncertainty (ranging from 0.57 K at 10 GHz to 2.29 K at 85 GHz) lead to a 3.6% change in the retrieved global-average oceanic rainfall rate, and 10%–20% (20%–40%) shifts in the pixel-level (monthly) frequency distributions for given rainfall bins. A mathematical expression de.
DISCOVERY OF MULTIPLE PULSATIONS IN THE NEW δ SCUTI STAR HD 92277: ASTEROSEISMOLOGY FROM DOME A, ANTARCTICA

We report the discovery of low-amplitude oscillations in the star HD 92277 from long, continuous observations in the r and g bands using the CSTAR telescopes in Antarctica. A total of more than 1950 hours of high-quality light curves were used to categorize HD 92277 as a new member of the δ Scuti class. We have detected 21 (20 frequencies are independent and one is the linear combination) and 14 (13 frequencies are independent and one is the linear combination) pulsation frequencies in the r and g bands, respectively, indicating a multi-periodic pulsation behavior. The primary frequency f1 = 10.810 days−1 corresponds to a period of 0.0925 days and is an l = 1 mode. We estimate a B − V index of 0.39 and derive an effective temperature of 6800 K for HD 92277. We conclude that long, continuous and uninterrupted time-series photometry can be performed from Dome A, Antarctica, and that this is especially valuable for asteroseismology where multi-color observations (often not available from space-based telescopes) assist with mode identification.
DECAY AND GROWTH RATES OF SOLUTIONS OF SCALAR STOCHASTIC DELAY DIFFERENTIAL EQUATIONS WITH UNBOUNDED DELAY AND STATE DEPENDENT NOISE

This paper studies the growth and decay rates of solutions of scalar stochastic delay differential equations of Ito type. The equations studied have a linear drift which contains an unbounded delay term, and a nonlinear diffusion term, which depends on the current state only. We show that when the nonlinearity at zero or infinity is sufficiently weak, the same non-exponential decay and growth rates found in the corresponding underlying linear deterministic equation are recovered, in an almost sure sense.
Quadratic guaranteed cost control with robust pole placement in a disk

The paper is concerned with the design of robust state feedback controllers for a class of uncertain systems with norm bounded uncertainty, where uncertainty enters in both the state and input matrices. The controller is designed to place the closed loop poles of the uncertain system in a specified disk and guarantees an upper bound on a quadratic cost function. A procedure is given for the construction of a controller which minimises a bound on an integral quadratic performance index.
Recent advancement in transcranial brain imaging using photoacoustic computed tomography

Photoacoustic computed tomography (PACT) holds great promise for transcranial brain imaging. However, the strong reflection, scattering, and attenuation of acoustic waves by the skull present significant challenges for image reconstruction. In this talk, we will review our recent progress on transcranial PACT image reconstruction. Our contributions include the following: (1) development of a methodology to establish a discrete transcranial PACT image model by use of adjunct X-ray CT data; (2) development of image reconstruction methods that can compensate for speed-of-sound and density variations within the skull; and (3) a detailed investigation of the role of shear waves in transcranial PACT. Computer-simulated and experimental data are employed to demonstrate the feasibility of transcranial PACT.
Effect of low-temperature annealing on transport and magnetism of diluted magnetic semiconductor (Ga, Mn)As

We report improvements in the crystallinity of a III–V-based diluted magnetic semiconductor (Ga, Mn)As by heat treatment (annealing) after growth at comparatively low temperatures. This method can be used to raise the Curie temperature to 100 K without the need for severe optimization of growth conditions, as well as to adjust the material parameters to desired values.
Unified analysis of variance by ranks

Many ‘distribution-free’ statistical tests using very different computational procedures can be viewed as special cases of two general tests based on the principle of analysis of variance by ranks. The first test, due to Bernard & Van Elteren (1953), is a general test for any differences among the samples. The second test evaluates trends and contrasts between the samples. The two general procedures embrace popular tests by Friedman, Kruskal, Cochran, Spearman, Wilcoxon, Mann & Whitney, Dixon & Mood, Page and Marascuilo & McSweeney as well as chi-square tests for contingency tables whose dependent variable is in the form of dichotomous or rankable categories. The system can be used to generate convenient computational formulac for a range of new designs, to express popular procedures in a unified notation, as a teaching aid to illustrate the relationships among tests and as the basis for a simple computer program to analyse data from any design within the system.
Absorption Properties of Lanthanum and Samarium Substituted Barium Titanates

This paper deals with the investigation of structural and absorption properties of microwave dielectric ceramics with the general formula Ba6–3xR8+2xTi18O54 where R = La, Sm and x = 2/3. The X-ray diffraction analysis revealed tungsten bronze type crystal structure with orthorhombic symmetry for these ceramics. The scanning electron micrograph shows uniform needle like elongated grains. Absorption properties i.e. absorption loss, return loss and insertion loss have been measured for the synthesised samples with respect to the frequency in the range 8.0 GHz–12.0 GHz at room temperature.
Resonance absorption of compressible magnetohydrodynamic waves at thin “surfaces”

If an MHD surface wave is supported by a true discontinuity, then the total pressure fluctuation, {delta}P{sub tot}, is constant across the discontinuity. If the discontinuity is replaced by a thin transition layer, then {delta}P{sub tot}, will be approximately constant across the transition layer, with a value approximately the same as the value obtained for the case of a true discontinuity. We use this approximation to study the behavior of the plasma and fields in the transition layer. The authors regard {delta}P{sub tot} as known, and write the relevant equations in forms in which {delta}P{sub tot} appears as driving terms. Two resonances appear. The cusp resonance affects the density and pressure fluctuations, and the velocity and magnetic field components along the background magnetic field, B{sub o}. The Alfven resonance affects the velocity and magnetic field components normal to B{sub o}. They concentrate on the Alfven resonance, and show in a simple way how energy is pumped out of the surface wave into thin layers surrounding the resonant field lines. They consider also the effects of three types of viscosity on the Alfven resonance. Only classical shear viscosity is able to absorb the energy which is pumped into the thin resonantmore » layer. In the steady state, the net viscous heating is independent of the viscosity coefficient, if the heating occurs in a sufficiently thin layer. They suggest that the large velocity shears which occur in the vicinity of the resonant field lines can lead to Kelvin-Helmholtz instabilities, which can in turn lead to an effective eddy viscosity, which they estimate to be large enough in the solar corona to distribute heat throughout large portions of coronal active region loops. They show also that coronal heating by the Alfven resonance is compatible with a variety of coronal data. « less
Proper Orthogonal Decomposition Reduced-Order Model for Nonlinear Aeroelastic Oscillations

In this study, the proper orthogonal decomposition method in conjunction with a Galerkin projection scheme is employed to solve the title problem of a fluttering plate in both two and three dimensions undergoing supersonic flow using von Karman’s large deflection plate theory and quasi-steady supersonic aerodynamic theory. Proper-orthogonal-decomposition-based reduced-order models are constructed by using the responses as snapshots from the conventional Galerkin method, which also plays a role as a reference method in this paper. Results for the buckled, limit cycle oscillation, and chaotic responses of the simply supported plate are presented and compared with the Galerkin solutions. Numerical examples demonstrate that the proper orthogonal decomposition reduced-order model permits a much lower-dimensional model as compared to that obtainable via the Galerkin approach. For example, for a plate length-to-width ratio equal to 4, only two proper orthogonal decomposition modes are required to describe the pa.
Testing ignorable missingness in estimating equation approaches for longitudinal data

We address the matter of determining whether or not missing data in longitudinal studies are ignorable with regard to quasilikelihood or estimating equations approaches. This involves testing for whether or not the zero-mean property of estimating equations holds true. Chen & Little (1999) proposed testing for significant differences among parameter estimators calculated from sample subsets with different patterns of missing data, whereas we propose a more unified generalised score-type test. This avoids exhaustive estimation of parameters for each missing-data pattern, testing instead with a single quadratic score test statistic whether or not there is a common parameter under which the means of all the pattern-specific estimating equations are zero. Comparisons are made for the two approaches with both simulations and real data examples. Copyright Biometrika Trust 2002, Oxford University Press.