Miracle-dz/UniFAR-FTUs huggingface dataset:
The Redesign of the Census Current Population Survey

Abstract In February 1954 a redesign of the Current Population Survey was introduced that provided for a more efficient system of field organization and supervision as well as some advances in methods. The sample is now spread over 230 areas instead of 68 areas with the same number of households as heretofore. A composite estimation procedure has been introduced which reduces the sampling variability for most estimates. Also, there has been a considerable reduction in the variance of variance estimates made from the sample. A statistical quality control program has been introduced to help insure results of consistently acceptable quality. Problems arose in the process of shifting from one design to the other that resulted in some significant differences between the new and old samples for a few of the estimates, especially unemployment. Apparently response errors were the principal source of difficulty, and it was possible to take steps to bring the results within sampling error range. Work on the measure.
Evaluating Phishing Reports shared on Twitter

—Phishing attacks are an increasingly potent web-based threat, with nearly 1.5 million websites created on a monthly basis. In this work, we present the ﬁrst study towards identifying such attacks through phishing reports shared by users on Twitter. We evaluated over 16.4k such reports posted by 701 Twitter accounts between June to August 2021, which contained 11.1k unique URLs, and analyzed their effectiveness using various quantitative and qualitative measures. Our ﬁndings indicate that not only do these users share a high volume of legitimate phishing URLs, but these reports contain more information regarding the phishing websites (which can expedite the process of identifying and removing these threats), when compared to two popular open-source phishing feeds: PhishTank and OpenPhish. We also notice that the reported websites had very little overlap with the URLs existing in the other feeds, and also remained active for longer periods of time. But despite having these attributes, we found that these reports have very low interaction from other Twitter users, especially from the domains and organizations targeted by the reported URLs. Moreover, nearly 31% of these URLs were still active even after a week of them being reported, with 27% of them being detected by very few anti-phishing tools, suggesting that a large majority of these reports remain undiscovered, despite the majority of the follower base of these accounts being security focused users. Thus, this work highlights the effectiveness of the reports, and the beneﬁts of using them as an open source knowledge base for identifying new phishing websites.
Trend Analysis of Extreme Precipitation Using Quantile Regression

The underestimating trend using existing ordinary regression (OR) based trend analysis has been a well-known problem. The existing OR method based on least squares approximate the conditional mean of the response variable given certain values of the time t, and the usual assumption of the OR method is normality, that is the distribution of data are not dissimilar form a normal distribution. In this regard, this study proposed a quantile regression that aims at estimating either the conditional median or other quantiles of the response variable. This study assess trend in annual daily maximum rainfall series over 64 weather stations through both in OR and QR approach. The QR method indicates that 47 stations out of 67 weather stations are a strong upward trend at 5% significance level while OR method identifies a significant trend only at 13 stations. This is mainly because the OR method is estimating the condition mean of the response variable. Unlike the OR method, the QR method allows us flexibly to detect the trends since the OR is designed to estimate conditional quantiles of the response variable. The proposed QR method can be effectively applied to estimate hydrologic trend for either non-normal data or skewed data.
An Observational and Numerical Study of a Cold Front Interacting with the Olympic Mountains during COAST IOP5

Abstract This paper documents the three-dimensional flow and precipitation structures associated with a weak cold front interacting with the Olympic Mountains and the subsequent development of a Puget Sound convergence zone. This study utilizes data collected during COAST IOP5 (the fifth intensive observing period of the Coastal Observation and Simulation with Topography field experiment) that took place on 11–12 December 1993. One of the most important data sources was a NOAA P-3 aircraft, which provided flight-level data, radar reflectivity, and Doppler winds as it circumnavigated the Olympics. Initially, frontal passage along the western foothills of the Olympics was accompanied by a 2°–3°C temperature drop, a rapid wind shift to northwesterlies, and an intense line of precipitation (35–45 dBZ); however, the wind shift and associated precipitation structures attenuated when the front began to ascend the windward slopes of the Olympics. Surface and P-3 observations document the deformation of the front .
Computational/experimental investigation of staged injection into a Mach 2 flow

The stage normal injection of two jets of air into a Mach 2 freestream behind a rearward-facing step has been investigated using laser-induced iodine fluorescence and laser doppler anemometry techniques. A detailed data set has been compiled that includes profiles of pressure, temperature, two components of velocity, and mole fraction of the injectant at 44 locations, plus planar surveys of pressure, temperature, velocity, and mole fraction. A companion numerical study was performed using the SPARK Navier-Stokes code. Good overall agreement was observed for this complex, highly three-dimensional flowfield. Discrepancies were observed in the computed and measured total temperatures, turbulent mixing, and shock strengths. The effect of grid resolution was investigated by calculating solutions on grids of 60,000 points, 200,000 points, and 450,000 points. Differences in the solutions on the two finer grids were small. The effect of turbulence modeling was investigated by calculating solutions with three different algebraic models for the jet turbulence. Overall, the turbulence models were found to have the greatest effect on the numerical solutions, followed by the grid resolution and the injectant Mach number.
A mathematical model for MIMO imaging

Multiple Input Multiple Output- MIMO Radar is a fast growing research area. This paper will give a brief introduction to the subject as well as derive an image formation scheme. The general problem of radar imaging is to use some physical model for a transmitted signal, and measurements of the signal that is scattered back to a receiver by a scene to attempt to derive information about the scene. The concept of communication involves a message sender, a message receiver, and a channel. The sender sends a message through the channel to the receiver. The receiver attempts to recover the original message. MIMO communication is just communication that involves sending several messages to several recipients. The problem of Multiple Input Multiple Output Radar Imaging is to use the corruption of transmitted messages to try and derive useful information about the environment that the messages traveled through. The extra information gained with MIMO Radar can be used to get rid of false targets, detect moving targets, and create a better resolution image. The plan for this research is to culminate to an in-scene 3-d Image reconstruction algorithm. The model presented provides a context in which to examine this problem.
An Efficient and Fast Iris Location Algorithm

The edge information of pupil was extracted by the least-square method, and the iris outer circle was extracted by the improved Canny Operator plus Hough Transform. The segmental-secondary linear localization method adopting edge detection and Radon Transform was proposed to remove the noise from eyelid on the eyelid localization, the eyelash noise and eyelid shadows were removed by threshold method.
3. Multilevel Covariance Structure Analysis by Fitting Multiple Single-Level Models

Data in social and behavioral sciences are often hierarchically organized. Multilevel statistical procedures have been developed to analyze such data while taking into account the dependence of observations. When simultaneously evaluating models at all levels, a significant statistic provides no information on the level at which the model is misspecified. Model misspecification can exist at one or several levels simultaneously. When one level is misspecified, the other levels may be affected even when they are correctly specified. Motivated by these observations, we propose to separate a multilevel covariance structure into multiple single-level covariance structure models and to fit these single-level models as in conventional covariance structure analysis. A procedure for segregating the multilevel model into single-level models is developed. Five test statistics for evaluating a model at each level are provided. Standard error formulas for the separate estimators are also provided, and their efficiency is compared to simultaneous estimators. Empirical and Monte Carlo results demonstrate the advantages of the segregated procedure over the simultaneous procedure. Computer programs that will allow the developed procedure to be used in practice are also presented.
Sound radiation from a semi‐infinite circular pipe having an arbitrary profile of orifice

A general solution for the sound radiated from a circular pipe having an arbitrary inside profile of orifice is obtained by the use of Laplace transforms and the Wiener–Hopf technique. The pipe may include vibrating surfaces. Results are calculated for the velocity potential at a large distance from the orifice and for the reflection coefficient for the dominant‐mode component of the velocity potential in the pipe. The solution is applicable, for example, to the design of an acoustic transducer, and for noise control from the orifice. Some numerical results for the velocity potential of a model loudspeaker and for the excess attenuation of a muffler near the open end of a pipe are presented graphically.Subject Classification:[43]20.55, [43]20.15.
A Numerical Model of the Sea-Breeze Phenomenon over a Lake or Gulf

Abstract A two-dimensional primitive equation model is constructed and used to investigate the circulations induced by differential heating in the vicinity of a land-locked semi-infinite body of water. The semi-empirical boundary-layer formulation of Clarke is used with an expanding σ grid of 15 vertical levels. Surface temperature is computed by means of a heat-flux balance equation and a radiation condition is used at the lateral boundaries. For purposes of comparison, one run was also made with reflective boundary conditions and it was found that the two solutions differ significantly only when the sea-breeze front is in the vicinity of a lateral boundary. The model reproduces the vast sea breezes of Australia, some of which have been observed to penetrate distances of 200–300 km inland. This feature of the model is attributed to the detailed boundary-layer formulation, in which the momentum and heat exchange coefficients are expressed as functions of stability and wind shear at all levels, and also to.
A review of free‐electron lasers

Free‐electron laser (FEL) theory and experiments are reviewed. The physical mechanism responsible for the generation of coherent radiation in the FEL is described and the fundamental role of the ponderomotive wave in bunching and trapping the beam is emphasized. The relationship of the FEL interaction to the beam–plasma interaction is pointed out. Various FEL operating regimes are discussed. These include the high‐gain Compton and Raman regimes, both with and without an axial guiding magnetic field. The linear and nonlinear regimes are examined in detail, with particular emphasis on techniques for achieving efficiency enhancement. The quality of the electron beam used to drive FEL’s is a critical factor in determining their gain and efficiency. The subject of electron beam quality, for different accelerators, is discussed. Key proof‐of‐principle experiments for FELs in an axial guiding magnetic field, as well as those driven by induction linacs, rf linacs, electrostatic accelerators, and storage rings, ar.
Efficient Osteoporosis Prediction Using A Pair of Ensemble Models

[Abstract] In this paper, we propose a prediction model for osteopenia and osteoporosis based on a convolutional neural network(CNN) using computed tomography(CT) images. In a single CT image, CNN had a limitation in utilizing important local features for diagnosis. So we propose a compound model which has two identical structures. As an input, two different texture images are used, which are converted from a single normalized CT image. The two networks train different information by using dissimilarity loss function. As a result, our model trains various features in a single CT image which includes important local features, then we ensemble them to improve the accuracy of predicting osteopenia and osteoporosis. In experiment results, our method shows an accuracy of 77.11% and the feature visualize of this model is confirmed by using Grad-CAM.
Pd/AlN/SiC thin-film devices for selective hydrogen sensing

A hydrogen sensing device has been fabricated using a 1500- A-thick AlN layer interposed between a SiC substrate and a Pd gate. This device behaves as a rectifying diode. Hydrogen in the gas flow causes a shift in the forward conduction and the sensitivity of the device is found to increase with the total flow rate. At a device temperature of 300 °C and a flow rate of 1000 sccm, the typical forward current of ∼1 mA increases by 10% for 10 ppm hydrogen, independent of the presence of oxygen or CO in the gas flow. The shift is also independent of the presence of propane. However, for very large concentrations of propane a slight response can be discerned, due to the presence of some hydrogen resulting from the incipient decomposition of the hydrocarbon at elevated temperature.
Variable range hopping and/or phonon-assisted tunneling mechanism of electronic transport in polymers and carbon nanotubes

We review and compare two models recently used to describe electronic transport in polymer fibers/nanotubes and carbon nanotubes including graphene nanoribbons, namely, variable range hopping (VRH) in different versions and their modifications on the one hand and electric-field-induced phonon-assisted tunneling (PhAT) on the other hand. The VRH model is mainly approved on behalf of the results of temperature dependences. However, the field dependencies of the conductivity in the framework of this model remain practically unexplained. At the same time, the PhAT model describes properly not only temperature dependence of conductivity measured in a wide temperature range, but also conductivity/current dependences on field strength using the same set of parameters characterizing the materials
A method of two‐dimensional spectral analysis using the wigner distribution

Wigner distribution (WD) has recently attracted attention as a powerful tool for time-varying signals analysis and several applications have been proposed. WD is calculated as the Fourier spectra of a signal with special preprocessing. The preprocessing allows the frequency resolution to be better than that of Fourier transform (FT). However, this preprocessing causes WD to generate interference terms and more complicated aliasing compared to FT. To cope with these problems, WD is usually calculated using analytic signals. In one-dimension, the method of deriving analytic signal is unique. However, in two-dimensions (2-D), several methods have been proposed. This paper presents the reason for 2D-WD to generate aliasing and interference for negative frequency components and its solution. Based on the discussion, a new analytic signal for 2D-WD is proposed together with a method of new spectral analysis using the signal. The proposed method offers higher frequency resolution and no interference term for negative frequency components, as well as no aliasing, providing characteristics similar to WD. By using this method, spectral analysis for low frequencies can be realized with small-sized windows.
Influence of Purity on the Dynamic Recrystallization of Metals and Alloys

The availability of high-purity metals and high-purity based alloys has recently allowed us to better understand the various processes of dynamic recrystallization (DRX) that take place during hot working. According to the mobility of dislocations and the subsequent efficiency of dynamic recovery (which mainly depends on stacking-fault energy), continuous (CDRX) or discontinuous (DDRX) dynamic recrystallization may take place. In aluminium, recent work has shown that a transition from CDRX to DDRX occurs with increasing purity, whereas in austenitic stainless steels close to the AISI 304L grade, DDRX is observed whatever the purity. A simple theoretical criterion for this transition is proposed and discussed. The key parameter is the grain boundary migration rate, whose temperature dependence is analyzed first. For the influence of purity, an indirect approach is then proposed on the basis of a model recently developed for CDRX.
On the behaviour of baroclinic waves undergoing horizontal deformation. I: The ‘RT’ phase diagram

Non-modal baroclinic wave growth in an idealizsed flow comprising baroclinic shear and horizontal confluence is considered. It is shown how a general semi-analytic solution may be derived for the evolution of non-modal waves with uniform potential vorticity in this ‘mixed’ basic state. The solution is new. It represents a synthesis of baroclinic waves with pure deformation solutions. For a given initial wavelength the solution is capable of describing an infinite number of distinct non-modal developments. To overview this large variety, phase diagrams, dubbed ‘RT’ diagrams, have been developed. The diagrams depict the evolution of vertical structure for a wide range of initial conditions. Some specific solutions with relevance to type B cyclogenesis and the potentially destablizing effect of deformation are discussed.
Size and strain effects in the E1-like optical transitions of InAs/InP self-assembled quantum dot structures

The optical transitions of uncapped and capped InAs/InP self-assembled quantum dot structures in the energy range of the bulk InAs E1 transition are studied using modulation spectroscopy and Raman scattering. Islands and wetting layer exhibit one and two features, respectively. The deformation potential theory and the single band effective mass approximation account for the island-related feature successfully in a wide island-height range (3–7 nm). These models also explain the existence of the highest energy wetting layer related feature, but not of the lowest energy one.
Hubble Space Telescope GHRS Spectroscopy of U Geminorum during Two Outbursts

We obtained Hubble Space Telescope Goddard High-Resolution Spectrograph medium-resolution (G160M grating) phase-resolved spectroscopic observations of the prototype dwarf nova U Geminorum during different stages of two different outbursts. The spectral wavelength ranges were centered on three different line regions: N V (1238 Å, 1242 Å), Si III (1300 Å), and He II (1640 Å). The spectrum corresponding to the early decline phase of outburst 1 is essentially featureless except for weak N V absorption and narrow interstellar lines, while the spectrum at the peak of outburst 2 reveals broad emission peaks separated by narrow central absorption. The double-peaked emission-line profile structure with low-velocity central absorption seen in the second outburst suggests a disk origin, but the emission velocity widths appear narrower than the widths of the optical disk emission features. We interpret the high-excitation emission lines, with central absorption below the continuum, to be due to photoionized material (coronal? ) above the disk plane with the thickened outer disk absorbing the boundary layer or inner disk radiation. The possibility of a wind origin for the profiles is also discussed, as well as the possibility of an ejected optically thin shell. The N V absorption velocity versus orbital phase traces the motion of the white dwarf, but the He II absorption velocity appears to deviate from the white dwarf motion. We present the results of synthetic accretion disk spectral fitting to the data of both outbursts and derive accretion rates for the two outbursts of 6 × 10-10 M☉ yr-1 and 2 × 10-9 M☉ yr-1. Implications are discussed.
Microscopic investigation of InGaN/GaN heterostructure laser diode degradation using Kelvin probe force microscopy

We report on Kelvin probe force microscopy (KPFM) measurements on fresh and artificially aged InGaN/GaN laser test structures. In the case of an unbiased laser diode, a comparison of the surface potential between a fresh and a stressed laser diode shows a pronounced modification of the laser facet due to the aging process. Performing KPFM measurements under forward bias, a correlation between the macroscopic I–V characteristics and the microscopic voltage drop across the heterostructure layer sequence is found. This clearly demonstrates the potential of KPFM for investigating InGaN/GaN laser diode degradation.
Stability Analysis of Two-Segment Stepped Columns with Different End Conditions and Internal Axial Loads

Members with varying geometrical and/or material properties are commonly used in many engineering applications. Stepped columns with internal axial loads constitute a special case of such nonuniform columns. Crane columns in industrial buildings or structural columns supporting intermediate floors are important applications of stepped members in civil engineering. Since neither axial load nor stiffness is constant along the column height, the stability analysis of a stepped column is usually more complicated than that of a uniform column. Determination of exact buckling loads for stepped columns with different end conditions is not always practical. This paper shows that variational iteration method (VIM), a kind of analytical technique recently proposed for solution of nonlinear differential equations, can satisfactorily be used to obtain approximate solutions for buckling loads of stepped columns with internal axial loads. VIM solutions perfectly match with the exact solutions available in the literature for some special cases of two-segment stepped columns. For many other cases, that is, for various values of three design parameters, namely, (i) load ratio, (ii) stiffness ratio, and (iii) length ratio, approximate buckling loads for two-segment stepped columns are determined using VIM and presented in tabular form which can easily be used by design engineers.
Spectroscopic survey of Kepler stars: high-resolution observations of A- and F-type stars

Abstract Basic stellar parameters such as effective temperature, surface gravity, chemical composition, and projected rotational velocity, are important to classify stars and are crucial for successful asteroseismic modelling. However, the Kepler space data do not provide such information. Therefore, ground-based spectral and multi-colour observations of Kepler asteroseismic targets are necessary to complement the space data. For this purpose, in coordination with the KASC ground-based observational Working Groups, high-resolution spectroscopic data for more than 500 B, A, F and G-type stars were collected.