Miracle-dz/UniFAR-FTUs huggingface dataset:
Midrank unification of rank tests for exact, tied, and censored data

Ties, right censoring, left censoring, and interval censoring can all cause ambiguity about the rank of an observation. Therefore traditional rank tests for uncensored data without ties need to be adjusted in the presence of uncertainty about the rank assigned to an observation. A simple solution that can be used in any situation where the rank assigned to an observation is ambiguous is to replace the unknown rank of an observation with its midrank. We derive properties of the midranks and, in turn, generalizations of ranks tests for the two sample problem, matched pairs and competing risks in the presence of censoring. Several previously proposed rank tests for censored data are shown to be equivalent to midrank tests.
Synthesis and luminescent properties of Gd3Ga2Al3O12 phosphors doped with Eu3+ or Ce3+

Eu3+-or Ce3+-doped gadolinium gallium aluminum garnet (GGAG), Gd3Ga2Al3O12, phosphors are fabricated using solid-state reactions with Gd2O3, Ga2O3, Al2O3, CeO2 and Eu2O3 powders. The Eu3+-or Ce3+-doped Gd3Ga2Al3O12 phosphors are sintered at 1300 °C or 1600 °C for 5 hours by using an electric furnace under normal atmosphere. X-ray diffraction and field-emission scanning electron microscopy studies are carried out in order to analyze the physical properties of these materials, and their luminescence properties are also measured by using UV and X-ray sources. The Eu3+-or Ce3+-doped Gd3Ga2Al3O12 phosphors show higher light yields in comparison to commercial phosphors such as Gd2O2S:Tb (gadox). This indicates that Gd3Ga2Al3O12:Eu3+ phosphors are promising materials for use in X-ray imaging and dose monitoring at proton beamlines.
RRR Characteristics for SRF cavities

The first heavy ion accelerator is being constructed by the rare isotope science project (RISP) launched by the Institute of Basic Science (IBS) in South Korea. Four different types of superconducting cavities were designed, and prototypes such as a quarter-wave resonator (QWR), a half-wave resonator (HWR) and a single-spoke resonator (SSR) were fabricated. One of the critical factors determining the performances of superconducting cavities is the residual resistance ratio (RRR). The RRR values essentially represent how pure niobium is and how fast niobium can transmit heat. In general, the RRR degrades during electron beam welding due to impurity incorporation. Thus, it is important to maintain the RRR above a certain value at which a niobium cavity shows target performance. In this study, RRR degradation related with electron beam welding conditions, for example, the welding power, welding speed, and vacuum level, will be discussed.
Hybridization of electron, light-hole, and heavy-hole states in InAs/GaSb quantum wells

We have investigated the hybridization of the electron states, the light-hole states and the heavy-hole states in InAs/GaSb broken-gap quantum wells. This effect is profound when the InAs layer and the GaSb layer are sufficiently thick such that the electron level lies below the heavy-hole level and the light-hole level at zone center. To calculate the dispersions and the wave functions in these structures we have applied the scattering matrix algorithm to the eight-band $\mathbf{k}\ensuremath{\cdot}\mathbf{p}$ model. We have found a hybridization gap as large as 20 meV resulting from the anticrossing of the electron and the light-hole dispersion curves. A multiple anticrossing of the electron states, the light-hole states and the heavy-hole states may occur when the heavy hole level lies in the hybridization gap produced by the electron states and the light-hole states. This unusual hybridization of the three subbands, which behaves differently for the ``spin-up'' and the ``spin-down'' states, has been investigated in details around the anticrossing point. While the electronlike and light holelike states mix strongly, the heavy holelike state may remain unperturbed.
Estimating vertical velocity and radial flow from Doppler radar observations of tropical cyclones

The mesoscale vorticity method (MVM) is used in conjunction with the ground‐based velocity track display (GBVTD) to derive the inner‐core vertical velocity from Doppler radar observations of tropical cyclone (TC) Danny (1997). MVM derives the vertical velocity from vorticity variations in space and in time based on the mesoscale vorticity equation. The use of MVM and GBVTD allows us to derive good correlations among the eye‐wall maximum wind, bow‐shaped updraught and echo east of the eye‐wall in Danny. Furthermore, we demonstrate the dynamically consistent radial flow can be derived from the vertical velocity obtained from MVM using the wind decomposition technique that solves the Poisson equations over a limited‐area domain. With the wind decomposition, we combine the rotational wind which is obtained from Doppler radar wind observations and the divergent wind which is inferred dynamically from the rotational wind to form the balanced horizontal wind in TC inner cores, where rotational wind dominates the divergent wind. In this study, we show a realistic horizontal and vertical structure of the vertical velocity and the induced radial flow in Danny's inner core. In the horizontal, the main eye‐wall updraught draws in significant surrounding air, converging at the strongest echo where the maximum updraught is located. In the vertical, the main updraught tilts vertically outwards, corresponding very well with the outward‐tilting eye‐wall. The maximum updraught is located at the inner edge of the eye‐wall clouds, while downward motions are found at the outer edge. This study demonstrates that the mesoscale vorticity method can use high‐temporal‐resolution data observed by Doppler radars to derive realistic vertical velocity and the radial flow of TCs. The vorticity temporal variations crucial to the accuracy of the vorticity method have to be derived from a high‐temporal‐frequency observing system such as state‐of‐the‐art Doppler radars. Copyright © 2006 Royal Meteorological Society
SEST observations of southern flat–spectrum radio sources

We present the results of a 2 & 3 mm Swedish–ESO Submillimetre Telescope continuum survey of bright southern flat–spectrum radio sources. Our sample consists of all sources in the PKSCAT90 catalog south of declination with accurate positions (), and predicted 3 mm flux (based on published low–frequency spectral indices) greater than 300 mJy (47 sources). In addition, 32 bright radio sources from the USNO Radio-Optical Reference Frame catalog have been observed. Our overall detection rate for the combined sample is 66% above typical limits of . This survey has identified many new sources suitable for use as phase and pointing calibrators for southern millimeter interferometers. A number of individual sources are discussed.
Relative local density of states and cloaking in finite clusters of coated cylinders

We describe a method for accurate calculation of the Relative Local Density of States (RLDOS) as a function of frequency and position in finite sets of coated cylinders. The RLDOS is important, since it describes the interaction between sources and their environment, which controls their ability to radiate electromagnetic waves. We give numerical examples of distributions of RLDOS for clusters of cylinders with lossy coatings whose optical properties are in the range typical of metamaterials, and use these to show the tendency of RLDOS to concentrate on the coating boundaries when plasmonic cloaking is occurring.
Approximating the distribution of the durbin-watson statistic

This paper derives approximations to the distribution of the Durbin-Watson statistic. When the coefficient of serial correlation is zero, the ap¬proximations are as good as other approximations proposed in the literature and probably somewhat easier to use. When serial correlation is present, the approximations are only moderately accurate. The problem is that the Edgeworth expansions derived here have difficulty replicating the shape of the true distribution function
Improved algorithmic cooling for scalable NMR quantum computers

The scaling of NMR ensemble computers is currently one of the main obstacles to building larger-scale quantum computing devices. To achieve scalability, one needs a large number of highly polarized spins in liquid nuclear-spin systems at finite temperature. In quantum computing terminology, such spin-half states are (almost) pure qubit states. Producing highly polarized spins (almost pure qubit states) out of non-polarized spins (non-pure qubit states) is sometimes called "purification". From a thermodynamic point of view, purification can be viewed as cooling spins to a very low temperature. In this preliminary work, we study the optimality of purification as a tradeoff between the number of cooled spins and the closeness of their quantum state to the ideal pure state.
Dosimetric verification of enhanced dynamic wedges by a 2D ion chamber array

Wedge filters are commonly used to achieve dose uniformity in the target volume in radiotherapy and can be categorized as physical wedges (PWs) and enhanced dynamic wedges (EDWs). The EDW generates PW-like dose profiles while moving the upper jaw in the Y directions with a varying dose rate in the treatment beams. Task Group 53 of the AAPM (American Association of Physicists in Medicine) recommended that the dynamic wedge be verified before implementation in the radiation treatment planning (RTP) system. The aim of this study was to use the I’mRT MatriXX to verify the dose profiles of the EDWs manufactured by Varian. We used Pencil Beam Convolution algorithms (eclipse 8.6) for the calculation and I’mRT MatriXX with Plastic Water® phantom MULTICube for dose measurements. The gamma indices of the calculations and the measurements for the EDWs were 84.84% and 86.54% in 2%/2 mm tolerance, and 99.47% and 99.64% in 3%/3 mm tolerance for wedge angles of 15°, 30°, 45° and 60°, respectively. The dose distributions differed between the calculations using the system and the measurements in the penumbra and the outer beam regions of the wedge fields. We confirmed that the dosimetric verifications of the EDW were acceptable when using the criterion for external beam dose calculations of Task Group 53.
Time-symmetry breaking in a modulated cold atom system: An ideal mean-field transition

We realize an ideal mean-field transition of time-translation symmetry in a periodically-driven atomic system. The symmetry in steady-state oscillatory atomic motions spontaneously changes with the total number of atoms due to the interplay between inter-atomic interactions which originate from the attenuation effects in the trapping laser light and thermal fluctuations. A large separation of the time scales governing the transition suppresses the spatial dependence of the system dynamics, leading to a mean-field behavior even close to the transition point.
Investigation of optical transmission loss by using a plasmonic Au nanoparticle assembly on a tapered fiber region

The optical transmission loss in a tapered fiber fabricated by using plasmonic Au nanoparticle deposition was investigated in the tapered region of the fiber. The amount of Au nanoparticle deposition was determined as a function of time, and the transmission loss was then compared with the losses of several spatial modes. The higher-order mode was found to affect the rate of increase in the transmission loss during the initial period of deposition, and a lower-order mode was found to contribute to the process during the latter period of deposition.
Orbital elements and an analysis of models for HDE 226868 = Cygnus X-1.

Radial velocities from 21 new high-dispersion spectrograms of HDE 226868 are presented. These are combined with previously published data to calculate a ''definitive'' set of orbital elements for the binary system. In particular, archival data are used to obtain a precise period. The ellipsoidal light curve is analyzed using both a Roche model and an ellipsoidal model, and the results are compared with work by Hutchings. Information from the absorption-line and emission-line velocity curves and the light curve is combined to give estimates for the orbital inclination and the component masses. The possible errors in the analysis are discussed and are shown to be negligible. A qualitative model for the mass transfer is proposed that explains the intensity and velocity variations of the optical emission lines and the variations in the X-ray intensity: including the low-energy X-ray absorption events sometimes seen near superior conjunction of the secondary. Tests of this model are also proposed. Finally, the observations are used to test various models that have been proposed for the system. The observations rule out low mass and rotating degenerate dwarf secondaries and present difficulties for the triple star model. The magnetic reconnection model is not ruled out by the observations.more » Models in which the secondary is a black hole are consistent with all available observations. (AIP)« less
Temperature-dependent structures and chemical bonding states of the calcium chlorapatite powders doped with rare-earth-ions

Calcium chlorapatite powders doped with rare-earth-ions are synthesized by using the solid-state reaction method and sintering at 1,100 ◦C and 1,300 ◦C, respectively. This study focuses on the crystal structures and the chemical bonding states of calcium chlorapatite powders for different sintering temperatures, doping elements, and doping concentrations. The characterized physical properties show that the apatite powders exhibit two phases based on the sintering temperatures: the powders sintered at temperatures below 1,100 ◦C have a hexagonal structure while those sintered at 1,300 ◦C have a monoclinic structure. That is, the apatite compounds sintered at higher temperatures show a structure with a lower space symmetry. The chemical bonding states of the synthesized powders remain unchanged regardless of the amount of doped rare-earths and the sintering temperature.
FORWARD MODELING CAVITY DENSITY: A MULTI-INSTRUMENT DIAGNOSTIC

The thermodynamic properties of coronal prominence cavities present a unique probe into the energy and mass budget of prominences. Using a three-dimensional morphological model, we forward model the polarization brightness and extreme-ultraviolet (EUV) emission of a cavity and its surrounding streamer. Using a genetic algorithm, we find the best-fit density model by comparing the models to Mauna Loa Solar Observatory MK4 and Hinode EUV Imaging Spectrometer data. The effect of temperature variations on the derived density is also measured. We have measured the density inside a cavity down to 1.05 R☉ with height-dependent error bars. Our forward modeling technique compensates for optically thin projection effects. This method provides a complementary technique to traditional line ratio diagnostics that is useful for diffuse off-limb coronal structures.
On the steady-state probability distribution of nonequilibrium stochastic systems

A driven stochastic system in a constant temperature heat bath relaxes into a steady state that is characterized by the steady-state probability distribution. We investigate the relationship between the driving force and the steady-state probability distribution. We adopt the force decomposition method in which the force is decomposed as the sum of a gradient of a steady-state potential and the remaining part. The decomposition method allows one to find a set of force fields each of which is compatible with a given steady state. Such a knowledge provides useful insight into stochastic systems, especially those in a nonequilibrium situation. We demonstrate the decomposition method in stochastic systems under overdamped and underdamped dynamics and discuss the connection between them.
Roots and decompositions of three-dimensional topological objects

In 1942 M.H. A. Newman formulated and proved a simple lemma of great importance for various fields of mathematics, including algebra and the theory of Gröbner-Shirshov bases. Later it was called the Diamond Lemma, since its key construction was illustrated by a diamond-shaped diagram. In 2005 the author suggested a new version of this lemma suitable for topological applications. This paper gives a survey of results on the existence and uniqueness of prime decompositions of various topological objects: three-dimensional manifolds, knots in thickened surfaces, knotted graphs, three-dimensional orbifolds, and knotted theta-curves in three-dimensional manifolds. As it turned out, all these topological objects admit a prime decomposition, although it is not unique in some cases (for example, in the case of orbifolds). For theta-curves and knots of geometric degree 1 in a thickened torus, the algebraic structure of the corresponding semigroups can be completely described. In both cases the semigroups are quotients of free groups by explicit commutation relations. Bibliography: 33 titles.
A search for massive dense cores with $^{\mathsf{13}}$CO J = 1-0 line

This paper reports 13 CO $J=1$-0 line observations toward 107 IRAS or H 2 O maser sources with the 13.7 m telescope of the Purple Mountain Observatory (PMO). Parameters of emission components are obtained and the profile characteristics are identified. For all the components, kinematic distances are derived. The bolometric luminosities of the corresponding IRAS sources are calculated for 95 sources, all of which are larger than 10 3 $L_{\odot}$. We also mapped eight sources. Results show that there are cores in the clouds. The sizes of the cores are about 1~3 pc, much greater and more extensive than those of cores in dark clouds. The hydrogen densities are ~10 2 -10 3 cm -3 . Systematic velocity shifts were found in 3 sources. Every mapped core contains one or more IRAS source. Each core has one and only one IRAS source that satisfies the criteria of ultra compact HII (UC HII) regions. For the cores, 2MASS data are available; dozens of 2MASS sources with different color indices and brightness are found within the core.
X-Band Amplifier for the PAL-XFEL

Recent X-ray free electron lasers based on a high-energy high-current linear accelerator, such as the Pohang Accelerator Laboratory (PAL-XFEL) uses a third harmonic radio-frequency (RF) linearizer system to improve the laser's longitudinal beam quality. Because the X-ray free electron laser at the PAL-Xfel uses 2856 MHz RF accelerators, we realized a RF linearizer of 11.424 GHz which afforded a 50 MW RF power by using a SLAC X-band klystron. Operation of the X-band klystron required an X-band amplifier with a 1 kW level at the specified frequency of 11.424 GHz. We tested two types of X-band amplifier, a traveling wave tube amplifier and a solid state amplifier. In this work, we present the test results and discuss the features, especially focusing on the X-band solid state amplifier.
Scattering of a High-Intensity, Low-Frequency Electromagnetic Wave by an Unbound Electron

"Thomson" scattering of a high-intensity, low-frequency, circularly-polarized electromagnetic wave by a free electron is considered. We find that by neglecting radiative corrections and pair effects, the Feynman-Dyson perturbation expansion is summable, and the sum can be analytically continued in the form of a sum of continued fractions. By imposing the boundary conditions that at $t=\ifmmode\pm\else\textpm\fi{}\ensuremath{\infty}$ the photons and target electron propagate as free particles, we obtain results which differ from those reported by Brown and Kibble and by Goldman. In particular our results differ in two aspects. The first difference is in the kinematics; namely, we find no intensity-dependent frequency shift in the scattered photon. The second difference is in the dynamics; that is, we obtain a different expression for the scattering amplitude. Both of these changes originate in the choice of boundary conditions. Instead of treating the asymptotic radiation field classically, we choose our states as linear combinations of occupation-number states. Finally, contact is made with the results of Brown and Kibble and of Goldman using a mixed set of classical and quantum boundary values.
First-principles calculations of the lattice instability and the symmetry-lowering modulation of PtSi

We have investigated the vibrational properties of orthorhombic PtSi by performing first-principles calculations. The calculated phonon band structure shows unstable phonon modes around the Γ-point. The ionic displacement vectors associated with the unstable Γ-point phonon mode suggest a structural modulation to a lower-symmetry phase, which was confirmed by comparing the theoretical equations of states of the modulated (P212121) and the unmodulated (Pnma) PtSi. The symmetry-reduced modulated orthorhombic PtSi shows a phonon band gap. We attribute the origin of the phonon band gap to the separation of the low-frequency Pt phonon modes and the high-frequency Si phonon modes due to the large atomic mass difference between Pt and Si.
Spatially resolved photocurrent mapping of operating organic photovoltaic devices using atomic force photovoltaic microscopy

A conductive atomic force microscopy (cAFM) technique, atomic force photovoltaic microscopy (AFPM), has been developed to characterize spatially localized inhomogeneities in organic photovoltaic (OPV) devices. In AFPM, a biased cAFM probe is raster scanned over an array of illuminated solar cells, simultaneously generating topographic and photocurrent maps. As proof of principle, AFPM is used to characterize 7.5×7.5μm2 poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester OPVs, revealing substantial device to device and temporal variations in the short-circuit current. The flexibility of AFPM suggests applicability to nanoscale characterization of a wide range of optoelectronically active materials and devices.
Contributions of low-luminosity sources to the X-ray background

HEAO 1 A-2 data are used to determine hard X-ray fluxes, or upper limits, for complete optically selected samples of active and normal galaxies, in order to estimate or to constrain their local X-ray luminosity functions. It is found that the luminosity function of Seyfert nuclei must flatten down drastically shortly below the observational limit of Piccinotti et al (1982); little can be added by dwarf active nuclei hidden in otherwise normal galaxies. Also analyzed is the possible contribution to the X-ray background from galaxies with strong star-formation activity, in the light of the possibility of a substantial cosmological evolution suggested by recent radio and IRAS data. 94 refs.
Spectral changes of a radial Gaussian Schell-model beam array propagating in non-Kolmogorov turbulence

The Spectral characteristics of a radial Gaussian Schell-model (GSM) beam array propagating in non-Kolmogorov turbulence are investigated theoretically. The spectrum of the GSM beam array is shown to be greatly influenced by both the source and the non-Kolmogorov parameters. The effects of the propagation distance, the spatial coherence of the source, the ring radius and the beam number of the array beam, the generalized exponent, and the inner scale parameters of non-Kolmogorov turbulence on the spectrum are studied in detail. The results show that two identical spectral maxima exist for the normalized on-axis spectrum and a rapid transition in spectrum can occur when the above-mentioned parameters have specific critical values. The effects of these parameters on the relative spectral shift are also studied in detail.