Miracle-dz/UniFAR-FTUs huggingface dataset:
Formation of Ohmic contact to semipolar (11-22) p-GaN by electrical breakdown method

The electrical breakdown (EBD) method was used to obtain Ohmic contact to semipolar (11-20) p-GaN surfaces using the Ti/SiO2/p-GaN structure. The EBD method by which the electrical stress voltage was increased up to 70 V with a compliance current of 30 mA resulted in an Ohmic contact with a specific contact resistance of 3.1×10−3 Ωcm2. The transmission electron microscope (TEM) analysis revealed that the oxygen was slightly out-diffused from SiO2 layer toward Ti surface and the oxidation occurred at the Ti surface, while the GaN remained unchanged.
Second-order-based blind signal separation in reverberant environments

The aim of this paper was to provide a derivation to explain the performance of the second-order-based blind signal separation (BSS) in reverberant environments. In particular, the second-order-based BSS algorithm, which exploits non-stationarity of the input signals, is investigated. The derivation provides a quantitative link between the reverberation parameter of the environment with the cost function of the BSS. Importantly, the theoretical finding complements existing literature on the interpretation of BSS and provides incremental insight to its performance.
Successes and challenges of the APP Coronagraph

Abstract The Apodizing Phase Plate (APP) coronagraph has been used to image the exoplanet β Pictoris b and the protoplanet candidate around HD 100546, and is currently in use in surveys with NaCo at the VLT. Its success is due to its tolerance to tip-tilt pointing errors in current AO systems, which degrade the performance of nearly all other coronagraphs. Currently the sensitivity of the APP is limited by non-common path errors in the science camera systems and by its chromatic behaviour. We present the achromatized Vector APP coronagraph and address how we will measure and minimise non-common path errors with Focal Plane Wavefront Sensing algorithms.
Numerical Methods for the Force Reflection of Contact

An important problem in the field of force-reflecting systems and telerobotics is poor rendering of contact, particularly of contact with stiff surfaces. There are numerous possible sources of poor performance, including poor contact models, sampling errors, and delays due to computation or data transmission. In this paper we examine effects due to sample-and-hold, which is a fundamental property of both the discrete domain and also of the sensors and power amplifiers used in a force-reflecting system. We propose sample-and-hold be generalized to sample-estimate-hold. We show why ordinary sample-and-hold generates an active contact interface, and provide ways of improving the feeling of the interface. We have developed a suite of numerical methods for improving the performance of rendering of surfaces by force reflection. We have conducted both simulations and experiments to demonstrate the efficacy of the proposed scheme. Our contributions are a new method of digitally processing force data, and a systematic method for coupling force-processing systems that run at different rates.
Transient photocurrent responses in amorphous Zn-Sn-O thin films

In this study we characterized the transient photocurrent responses in solution-processed amorphous zinc-tin-oxide (a-ZTO) thin films measured under light illumination with a wavelength of 400 nm at different temperatures. By using the temperature-dependent photoconductivities of a-ZTO thin films, we extracted the activation energies (Eac) of photo-excitation and dark relaxation through an extended stretched exponential analysis (SEA). The SEA was found to describe well the dark relaxation characteristics as well as the photo-excitation processes. The SEA also indicates that the dark relaxation process reveals a dispersive transient photoconductivity with a broader distribution of the Eac while the photo-excitation process shows non-dispersive characteristics. Samples exposed by light at temperatures less than 373 K possess the fast processes of photo-excitation and dark relaxation. This suggests that a fast process, for example, a generation/recombination of charged carriers related to a band-to-band transition and/or shallow/deep oxygen-vacancy (Vo) sub-gap donor states, is dominant in the case of light illumination at low temperatures of less than 373 K. The SEA indicates, however, that a much slower process due mainly to the delay of the onset of ionization/neutralization of the deep Vo states by multiple-trapping is dominant for samples under light illumination at a high temperature of 373 K. Based on the experimental results, for the dark relaxation process, we conclude that the process transitions from a fast recombination of electrons through band-to-band transitions and/or shallow/deep Vo donor states to a slow neutralization of the ionized Vo states occurs due to enhanced carrier multiple-trapping by relatively deep Vo trap states when the temperature becomes greater than 363 K. An energy band diagram of a-ZTO thin films was proposed in terms of the temperature and the Eac distribution to explain these observed results.
General relativistic white dwarfs and their astrophysical implications

We consider applications of general relativistic uniformly-rotating white dwarfs to several astrophysical phenomena related to the spin-up and the spin-down epochs and to delayed type Ia supernova explosions of super-Chandrasekhar white dwarfs, where we estimate the “spinning down” lifetime due to magnetic-dipole braking. In addition, we describe the physical properties of Soft Gamma Repeaters and Anomalous X-Ray Pulsars as massive rapidly-rotating highly-magnetized white dwarfs. Particularly we consider one of the so-called low-magnetic-field magnetars SGR 0418+5729 as a massive rapidly-rotating highly-magnetized white dwarf and give bounds for the mass, radius, moment of inertia, and magnetic field by requiring the general relativistic uniformly-rotating configurations to be stable.
Post‐Eruption Detection of Variable 12 in NGC 2403 (SN 1954j): Another η Carinae Variable

We have obtained optical and near‐infrared imaging photometry of the irregular variable V12 in NGC 2403 (SN 1954j), roughly 50 years after its giant eruption. The observations confirm that the star survived the event and that it was therefore not a peculiar supernova but instead was an η Carinae–like eruption. Variable 12 is now very faint and red, which could be due to extinction and reddening of a hot star by circumstellar dust that formed in ejecta from the giant eruption in 1954. A clear excess at ∼2 μm probably indicates thermal emission from hot circumstellar dust.
The Durham/UKST Galaxy Redshift Survey — I. Large-scale structure in the Universe

We present the first results from the Durham/UKST Galaxy Redshift Survey and consider their implications on current models of structure formation. This b J S 17 mag survey contains '" 2500 galaxy redshifts sampled at a rate of 1 in 3 from the Edinburgh/Durham Southern Galaxy Catalogue. We find that the galaxy distribution shows evidence of large 'cellular' features on 50-100 h -1 Mpc scales. This clustering has been statistically analysed using the 2-point correlation function, ~. The results show that the structures in this survey have power significantly in excess of the predictions of the standard cold dark matter (CDM) cosmological model on scales of 15-30 h -1 Mpc, and therefore support the previous observational results from the APM survey. At smaller scales, we measure the one-dimensional pairwise galaxy velocity dispersion in the Durham/UKST survey to be 387~~~ km S-I. This is also inconsistent with the prediction of the standard CDM model, assuming linear biasing. Finally, at larger scales, the Durham/UKST survey has produced the most accurate detection yet of large-scale redshift space distortions due to dynamical infall of galaxies. We obtain a best estimate of no. 6 /b = 0.55 ± 0.12, where n is the mean mass density of the Universe and b is the linear bias factor. Depending on the choice of b, this result is consistent either with a low-density universe (b ~ 1) or a critical-density universe (b ~ 2).
Wyner-Ziv Coding over Broadcast Channel with Noncausal Channel Side Information only Known at Encoder

We consider the problem of transmitting common message over discrete memoryless broadcast channel (DM-BC) with noncausal discrete memoryless (DM) channel side information (CSI) only known at encoder. Nayak, etc. consider this problem and give a scheme combining Wyner-Ziv coding and Gelfand-Pinsker coding. The Gelfand-Pinsker's code is optimal for point-to-point communication with the encoder accessed to noncausal CSI. But Nair, etc., show that the straightforward extension of Gelfand-Pinsker's code to DM-BC with DM state is not optimal. In this paper, the inner bound of transmitting common message over DM-BC with noncausal DM-CSI only known at encoder is given. The proof of achievability uses Wyner-Ziv coding, Gelfand-Pinsker coding, superposition coding, Marton coding and indirect decoding.
EFFECT OF SURFACE ROUGHNESS ON MAGNETIC PROPERTIES OF CO FILMS ON PLASMA-ETCHED SI(100) SUBSTRATES

Magnetic and morphological properties of ∼970-A-thick Co films, deposited simultaneously on ten plasma-etched Si(100) substrates, were measured through the magneto-optic Kerr effect (MOKE) technique, ferromagnetic resonance (FMR), magnetic force microscopy (MFM), and atomic force microscopy. As the etch time t increased from 0 to 100 min, the vertical interface width w of Co films increased from ∼5 to ∼1400 A; the lateral correlation length ξ, from ∼300 to ∼10 500 A. The MOKE and FMR measurements gave the in-plane azimuthal angular dependence of the hysteresis loops and the ferromagnetic resonance absorption spectra, respectively. From MOKE and FMR, the smoother films showed uniaxial magnetic anisotropy (t⩽40 min). The uniaxial anisotropy decreased with the increase of the surface roughness and disappeared for the roughest films (t=60 and 100 min). The MOKE hysteresis loop measurements suggested that, with the increasing surface roughness, the magnetization reversal changed gradually from magnetization ro.
Shear in the IRAS 3282 outflow

We have observed with high resolution the ammonia emission around IRAS 3282, a young star with a highly collimated molecular outflow. Our data show the outflow, passing through the core, accelerates the dense gas and produces a shearlike velocity field. The acceleration occurs along the walls of a cavity which the outflow seems to have evacuated
A Method for Generating New Solutions of Einstein's Equation. II

A scheme is introduced which yields, beginning with any source‐free solution of Einstein's equation with two commuting Killing fields for which a certain pair of constants vanish (e.g., the exterior field of a rotating star), a family of new exact solutions. To obtain a new solution, one must specify an arbitrary curve (up to parametrization) in a certain three‐dimensional vector space. Thus, a single solution of Einstein's equation generates a family of new solutions involving two arbitrary functions of one variable. These transformations on exact solutions form a non‐Abelian group. The extensive algebraic structure thereby induced on such solutions is studied.
The BV formalism for L ∞ -algebras

Functorial properties of the correspondence between commutative BV ∞ - algebras and L ∞ -algebras are investigated. The category of L ∞ -algebras with L ∞ - morphisms is characterized as a certain category of pure BV ∞ -algebras with pure BV ∞ -morphisms. The functor assigning to a commutative BV ∞ -algebra the L ∞ - algebra given by higher derived brackets is also shown to have a left adjoint. Cieliebak-Fukaya-Latschev’s machinery of IBL ∞ - and BV ∞ -morphisms is further developed with introducing the logarithm of a map.
Seeded supersonic alkali cluster beam source with refilling system

A supersonic sodium cluster beam source with a refilling system is described in detail. Due to the external refilling system a new loading of the oven, which is designed for high‐temperature application at 800 °C, is accomplished very fast and interrupts the measuring process only for 1–2 h. Additional purification of the alkali metal in the reservoir allows the usage of standard quality sodium samples.
Spectral classification of very late luminous stars in the Gaia region

We are using a sample of more than 50 standard very late-type stars, taken from Isaac Newton Telescope at R ~ 9000 in the 8100–9100 A range, in order to develop criteria for spectral and luminosity classification of very late-type stars in the Gaia region. In this article, we brief in a few pages the main challenges on this issue, as well as the literature about it, and we present some preliminary results.
The secret life of image plate phosphors

X‐ray imaging using storage phosphors is an increasingly popular method of taking data on synchrotron x‐ray stations. There are now commercially available scanners, which are being used at Daresbury and most other synchrotron light facilities worldwide. Although the basic principle behind the x‐ray stimulation and the subsequent readout of the phosphor has been known for a number of years, the details of the physical mechanisms have not been widely published and appear to be incompletely understood. Users of image plate systems might be surprised to learn of some of the observations made by the Daresbury Detector Development Group during the assessment of the storage phosphor technique as applied to x‐ray diffraction on the synchrotron. We present intriguing examples of yet unexplained phenomena which may need to be taken into account for experiments with very low experimental signal‐to‐noise ratios in their images. Possible future developments in image plate phosphors are also discussed.
Variance Estimation for Fractional Brownian Motions with Fixed Hurst Parameters

Some real-world phenomena in geo-science, micro-economy, and turbulence, to name a few, can be effectively modeled by a fractional Brownian motion indexed by a Hurst parameter, a regularity level, and a scaling parameter σ2, an energy level. This article discusses estimation of a scaling parameter σ2 when a Hurst parameter is known. To estimate σ2, we propose three approaches based on maximum likelihood estimation, moment-matching, and concentration inequalities, respectively, and discuss the theoretical characteristics of the estimators and optimal-filtering guidelines. We also justify the improvement of the estimation of σ2 when a Hurst parameter is known. Using the three approaches and a parametric bootstrap methodology in a simulation study, we compare the confidence intervals of σ2 in terms of their lengths, coverage rates, and computational complexity and discuss empirical attributes of the tested approaches. We found that the approach based on maximum likelihood estimation was optimal in terms of efficiency and accuracy, but computationally expensive. The moment-matching approach was found to be not only comparably efficient and accurate but also computationally fast and robust to deviations from the fractional Brownian motion model.
The dark matter problem from f(R) gravity viewpoint

An alternative view to the dark matter puzzle is represented by Extended Theories of Gravity. The approach consists in addressing issues like dark components from the point of view of gravitational field instead of requiring new material ingredients that, up to now, have not been detected at fundamental level. In this review paper, by extending the Hilbert‐Einstein action of gravitational field to more general actions (e.g. f(R) gravity), it is shown that several gravitating structures like stars, spiral galaxies, elliptical galaxies and clusters of galaxies can be self‐consistently described without asking for dark matter. It is also shown that standard General Relativity tests and Equivalence Principle constraints can be evaded at Solar System scales.
Hundreds of label-free cells tracking method based on multi-scale region of interest

Dielectrophoresis is a technology that uses the electrical properties of cells to control the movement of cells in a non-contact manner. It is important to observe cell movement in order to analyze cell characteristics using DEP technology. We developed an algorithm that can track the movement of hundreds of unlabeled cells by DEP force. The proposed algorithm consists of a cell detection step using a deep learning detection model and a cell tracking step based on a multiscale region of interest. Cell detection and tracking accuracy using Recall, precision, f-measure, and MOTA on a timelapse microscope image dataset has an accuracy of about 97% or more. In conclusion, by developing an automated tool that can perform imaging-based DEP cell analysis, cell tracking algorithms that can track hundreds of cells simultaneously can reduce cell analysis time and labor.
On the Minimal Entropy Martingale Measure and Multinomial Lattices with Cumulants

Abstract In this article, we describe with relevant examples based on empirical data how to use the minimal entropy martingale measure (MEMM) to price European and American Options in multinomial lattices which take into account cumulants information. For trinomial lattices, we show that minimal entropy prices are close to results obtained using the Black and Scholes option pricing formula. For pentanomial lattices, minimal entropy prices are close to results obtained under the mean-correcting martingale measure using the discrete Fourier transform. The MEMM is very easy to compute and is therefore a good candidate for option pricing in multinomial lattices.
PHASE CONJUGATE MIRRORS

Phase conjugate mirrors are attractive devices to improve the beam quality of lasers. At first, the fundamental properties of phase conjugate mirrors (PCMs) are summarized and a basic mathematical description is given. Degenerate four-wave mixing (DFWM) facilitates phase conjugation of weak signals and their amplification at the same time, but requires additional pumping beams. In contrast, self pumped phase conjugation is achieved by stimulated Brillouin scattering (SBS) in appropriate media. Liquids and gases of high purity as well as solid materials like silica fibers can be used with high efficiency. Solid-state laser systems with average output powers up to 500 W have been equipped with SBS phase conjugate mirrors to compensate for phase distortions in active media.
On Potential Vorticity and Transport in the Stratosphere

Abstract An attempt is made to relate tracer transport in the stratosphere to the requirements of atmospheric dynamics. The relationships are illustrated by considering the observed transport and budget of potential vorticity in the Southern Hemisphere. Eddy potential vorticity transports generally occur in association with upward fluxes of energy by the pressure-interaction mechanism. During the period studied, these transports were associated with significant but not major changes in the zonal mean flow. The eddy tracer transports inferred from the potential vorticity transport are consistent with the transports necessary to account for the distribution of atmospheric ozone. Dynamical considerations suggest that mixing length formulations for the mass transport by planetary waves are not strictly valid.
Inflammatory bowel disease and associated cardiovascular disease outcomes: A systematic review

Background: There is limited and conflicting data available regarding the cardiovascular disease outcomes associated with inflammatory bowel disease (IBD). Objective: We aim to perform a systematic review to evaluate the cardiovascular outcomes and mortality associated with IBD patients. Methods: A systematic literature search has been performed on PubMed, Embase, Cochrane, and Scopus from inception till May 2022 without any language restrictions. Results: A total of 2,029,941 patients were included in the analysis from 16 studies. The mean age of the patients was 45.6 years. More females were found compared with males (57% vs 43%). The most common risk factors for cardiovascular disease (CVD) included smoking (24.19%) and alcohol (4.60%). The most common comorbidities includes hypertension (30%), diabetes mellitus (14.41%), dyslipidemia (18.42%), previous CVD (22%), and renal disease (10%). Among outcomes, all-cause mortality among IBD patients was 1.66%; ulcerative colitis (UC): 15.92%; and Crohn disease (CD): 0.30%. Myocardial Infarction (MI) among IBD patients were 1.47%, UC: 30.96%; and CD: 34.14%. CVD events among IBD patients were 1.95%. Heart failure events among IBD patients were 5.49%, stroke events among IBD patients were 0.95%, UC: 2.63%, and CD: 2.41%, respectively. Conclusion: IBD patients are at higher risk for adverse cardiovascular outcomes, especially in women. Although there remains a lack of concrete treatment algorithms and assessment parameters that better characterize IBD risk factors, nutritional modifications and physical activity should be at the forefront of CVD prevention in IBD.
Structural characterization of temperature-and pressure-induced inverse↔normal spinel transformation in magnetite

G. Kh. Rozenberg,1 Y. Amiel,1 W. M. Xu,1 M. P. Pasternak,1 R. Jeanloz,2 M. Hanfland,3 and R. D. Taylor4 1School of Physics and Astronomy, Tel Aviv University, 69978 Tel Aviv, Israel 2Department of Earth and Planetary Science, University of California, Berkeley, California 94720, USA 3European Synchrotron Research Facility, Boite Postale 220, 38043 Grenoble, France 4MPA-10, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA Received 14 July 2006; revised manuscript received 4 December 2006; published 11 January 2007
Improvement of optical characteristics of Al0.48In0.52As grown by molecular beam epitaxy

The photoluminescence linewidth (4 K) of Al0.48In0. 52As was reduced to 15 meV and its dependence was determined to be a strong function of the substrate temperature and As4 overpressure. Raman spectroscopy correlates the luminescence broadening to the crystallinity of the AlInAs. The ratio of the allowed longitudinal optical phonon to forbidden transverse optical phonon Raman peak heights is 10:1.
Including virtual target points from laser scanning into the point-wise rigorous deformation analysis at geo-monitoring applications

We present a method to include virtual target points from laser scanning into the point-based rigorous deformation analysis to derive precise 3D deformation vectors. This method overcomes the challenge of missing point identities in laser scans and is developed especially for geo-monitoring applications that demand an early identification of deformations at previously unknown positions. Our approach is based on virtual targets represented by local scan patches. Each patch is matched between overlapping stations and across different measurement epochs using the Iterative Closest Point Algorithm (ICP). Thus, similar to feature points, a number of homologous points is created and polar pseudo-observations are derived. This allows to integrate the observations into a free network adjustment and into a rigorous deformation analysis. We apply this method to the geo-monitoring of rock surfaces on Mt. Hochvogel where we use a scanning total station combining point-wise measurements to signalized targets and pseudo-observations derived from area-wise laser scans. In our application, numerous virtual target points could be created throughout the deformation object. The results show that the new method improves the accuracy and reliability of the subsequent rigorous deformation analysis and it, thus, allows for an early identification of deformations at geo-monitoring applications. Still there is some improvement in the selection of suitable patches needed, as the matching accuracy of the ICP strongly depends on the point distribution within the patches.