Miracle-dz/UniFAR-FTUs huggingface dataset:
Post-Earthquake Landslide Extraction Based on Feature Expansion U-Net Model

Earthquake-induced landslide is the most common geological disaster caused by earthquakes, which seriously threatens the safety of human life and property. Rapid access to landslide information after the earthquake is the key to disaster mitigation and relief. The existing landslide extraction methods all require a lot of manual intervention and cannot provide timely and effective earthquake rescue information. In order to solve the above problems, this paper improves the traditional U -Net algorithm by feature expansion and proposes a FE-U-Net. This new method is applied to the landslide in Jiuzhaigou County, Sichuan Province, China by combining multi-source remote sensing images. The experimental results show that the F1-score, Kappa coefficient and mIOU values obtained by the proposed FE-U-Net are 95.02%, 94.23% and 94.47%, respectively, which are all about 3% higher than the traditional U -Net. In addition, the model training time is less than 10s longer than the traditional U -Net model.
Robust Multiscale Control-volume Methods for Reservoir Simulation

Multiscale methods can in many cases be viewed as special types of domain decomposition pre- conditioners. The localisation approximations intro- duced within the multiscale framework are dependent upon both the heterogeneity of the reservoir and the structure of the computational grid. While previous works on multiscale control volume methods have fo- cused on heterogeneous elliptic problems on regular Cartesian grids, we have tested the multiscale control volume formulations on two-dimensional elliptic prob- lems involving heterogeneous media and irregular grid structures. Our study shows that the tangential flow approximation commonly used within multiscale meth- ods is not suited for problems involving rough grids. We present a more robust mass conservative domain decomposition preconditioner for simulating flow in heterogeneous porous media on general grids.
A Passive Small Satellite Mission for Monitoring Ocean Health

The feasibility has been conducted of a multi-modal instrument called Oracle that was funded by ESA as part of its ‘Future EO passive optical missions for small satellites’ initiative in 2018. Oracle facilitates the simultaneous retrieval of ocean colour, sea skin temperature and aerosol optical depth using a colour imager, a thermal imager and a spectro-polarimeter respectively, to monitor changes in marine health. Oracle has been designed for accommodation in a microsatellite and contains an internal calibration device, which can be used by all three modes separately and simultaneously.
Superpixel Correction Based Label Propagation for Hyperspectral Images Classification

Superpixel based label propagation models have been successfully used for Hyperspectral Images (HSIs) classification especially when the training data are limited. However, it is inevitable that there are segmentation errors leading to data in one superpixel containing samples from different classes which could decrease the classification accuracy. In order to address this issue, we propose Superpixel Correction based Label Propagation for HSIs classification. First, superpixel segmentation technique is adopted to segment a HSI into many superpixel blocks. Then, clustering model density peak is used to adaptively cluster the data in each superpixel block to correct the segmentation errors. Finally, based on the corrected superpixel segmentation we construct global-local and spatial-spectral similarity graphs which results into effective propagation matrix for label propagation. The proposed model is verified in two HSIs data sets, and the experimental results demonstrate that the proposed model is superior to several state-of-the-art methods in terms of classification accuracy, especially in the case of limited training samples.
Satellite Monitoring of sea Surface Temperature and Chlorophyll for Sustainable Fishing

Here we will discuss two specific examples of how satellite data is being used to support the management of sustainable fisheries. The first example is a model to predict the potential sardine habitat along the US West Coast that relies on sea-surface temperature and chlorophyll data from JPSS VIIRS. The predicted habitat distribution is used to optimize the ship survey cruises conducted as part of the Pacific sardine stock assessment. The second example is the EcoCast model, which was developed as an effort to help minimize fishery bycatch. EcoCast identifies regions within the Pacific swordfish fishing grounds where the bycatch of protected and endangered species ([leatherback turtle, blue shark, and California sea lion) is less likely. This model also uses sea-surface temperature and chlorophyll data from JPSS VIIRS as two of its data inputs. Outputs from both the sardine habitat and EcoCast models are available on the NOAA CoastWatch West Coast Node ERDDAP server.
Persistent Scatterer Selection based on Phase Similarity of Radar Pixels

Persistent scatterer (PS) techniques are used to identify radar pixels with minimal phase decorrelation artifacts. Existing PS selection algorithms mostly focus on analyzing the phase stability at each radar pixel independently, and the spatial phase consistency is not fully exploited. In this study, we developed a new PS selection algorithm based on the phase similarity between nearby radar pixels. We tested this algorithm using C-band Envisat data over the San Luis Valley, Colorado, and C-band Sentinel-1 data over the Greater Houston area. In both cases, our algorithm identified PS pixels with lower false positive and false negative rates than existing PS identification techniques. We used InSAR phase measurements at those PS pixels to solve for surface deformation time series, which are consistent with independent validation data sets. Our InSAR processing strategy reveals subtle deformation signatures that are otherwise undetectable over densely vegetated regions.
Optimized robust combined feedforward/feedback control of propofol for induction of hypnosis in general anesthesia

In this paper an optimized robust feedforward/feedback control strategy for anesthesia induction is proposed. Propofol is used to induce hypnosis and the bispectral index scale (BIS) is employed as an indicator of depth of hypnosis. The control action is divided in two parts, a feedforward action, which acts alone in the first phase of anesthesia induction, and a feedback PID action that concludes the induction by smoothly driving the BIS to the target value. The feedforward action is given by an optimized bolus of propofol that is determined by taking into account the uncertainty of the nonlinear pharmacodynamic model for the effect of propofol on BIS. In particular, the bolus is obtained as the solution of a constrained minimum-time control problem in order to minimize the induction time of anesthesia while preventing the undershoot of the BIS level. Thus the patient’s safety is ensured by avoiding side-effects due to drug overdosing. The PID controller is then used in order to compensate for the deviation of the BIS from the theoretical behaviour caused by the effect of inter-patient and intra-patient variability.
Thermal instabilities in cooling galactic coronae: fuelling star formation in galactic discs

We investigate the means by which cold gas can accrete onto Milky Way mass galaxies from a hot corona of gas, using a new smoothed particle hydrodynamics code, ‘SPHS’. We find that the ‘cold clumps’ seen in many classic SPH simulations in the literature are not present in our SPHS simulations. Instead, cold gas condenses from the halo along filaments that form at the intersection of supernovae-driven bubbles from previous phases of star formation. This positive feedback feeds cold gas to the galactic disc directly, fuelling further star formation. The resulting galaxies in the SPH and SPHS simulations differ greatly in their morphology, gas phase diagrams, and stellar content. We show that the classic SPH cold clumps owe to a numerical thermal instability caused by an inability for cold gas to mix in the hot halo. The improved treatment of mixing in SPHS suppresses this instability leading to a dramatically different physical outcome. In our highest resolution SPHS simulation, we find that the cold filaments break up into bound clumps that form stars. The filaments are overdense by a factor of 10-100 compared to the surrounding gas, suggesting that the fragmentation results from a physical non-linear instability driven by the overdensity. This ‘fragmenting filament’ mode of disc growth has important implications for galaxy formation, in particular the role of star formation in bringing cold gas into disc galaxies.
Thermodynamic inconsistency in quasiparticle model - a revisit

Widely studied quasiparticle models for quark gluon plasma is revisited here to understand the statistical mechanics and thermodynamics of the system. We investigate the statistical mechanics and thermodynamics inconsistencies involved in these models and their consequences in the observables. Quasiparticle model is a phenomenological model with few parameters and by adjusting them all models fit the results of lattice gauge simulation of gluon plasma \cite{bo.1}. However, after fixing 2 of the 3 parameters of the model by physical arguments, only one quasiparticle model, which is consistent with both statistical mechanics and thermodynamics, fits the Bielefeld lattice data \cite{bo.1}. The same model also fits the recent lattice results of Wuppertal-Budapest group \cite{fo.1}, which deals with precision SU(3) thermodynamics for a large temperature range, reasonably well.
Competing order in correlated electron systems made simple: Consistent fusion of functional renormalization and mean-field theory

We derive an efficient and unbiased method for computing order parameters in correlated electron systems with competing instabilities. Charge, magnetic and pairing fluctuations above the energy scale of spontaneous symmetry breaking are taken into account by a functional renormalization group flow, while the formation of order below that scale is treated in mean-field theory. The method captures fluctuation driven instabilities such as $d$-wave superconductivity. As a first application we study the competition between antiferromagnetism and superconductivity in the ground state of the two-dimensional Hubbard model.
Active-set prediction for interior point methods

This research studies how to e ciently predict optimal active constraints of an inequality constrained optimization problem, in the context of Interior Point Methods (ipms). We propose a framework based on shifting/perturbing the inequality constraints of the problem. Despite being a class of powerful tools for solving Linear Programming (lp) problems, ipms are well-known to encounter di culties with active-set prediction due essentially to their construction. When applied to an inequality constrained optimization problem, ipms generate iterates that belong to the interior of the set determined by the constraints, thus avoiding/ignoring the combinatorial aspect of the solution. This comes at the cost of di culty in predicting the optimal active constraints that would enable termination, as well as increasing ill-conditioning of the solution process. We show that, existing techniques for active-set prediction, however, su↵er from di culties in making an accurate prediction at the early stage of the iterative process of ipms; when these techniques are ready to yield an accurate prediction towards the end of a run, as the iterates approach the solution set, the ipms have to solve increasingly ill-conditioned and hence di cult, subproblems. To address this challenging question, we propose the use of controlled perturbations. Namely, in the context of lp problems, we consider perturbing the inequality constraints (by a small amount) so as to enlarge the feasible set. We show that if the perturbations are chosen judiciously, the solution of the original problem lies on or close to the central path of the perturbed problem. We solve the resulting perturbed problem(s) using a path-following ipm while predicting on the way the active set of the original lp problem; we find that our approach is able to accurately predict the optimal active set of the original problem before the duality gap for the perturbed problem gets too small. Furthermore, depending on problem conditioning, this prediction can happen sooner than predicting the active set for the perturbed problem or for the original one if no perturbations are used. Proof-of-concept algorithms are presented and encouraging preliminary numerical experience is also reported when comparing activity prediction for the perturbed and unperturbed problem formulations. We also extend the idea of using controlled perturbations to enhance the capabilities of optimal active-set prediction for ipms for convex Quadratic Programming (qp) problems. qp problems share many properties of lp, and based on these properties, some results require more care; furthermore, encouraging preliminary numerical experience is also presented for the qp case.
Dynamics of test particles in the five-dimensional, charged, rotating Einstein-Maxwell-Chern-Simons spacetime

We derive the complete set of geodesic equations for massive and massless test particles of a five-dimensional, charged, rotating black hole solution of the Einstein-Maxwell-Chern-Simons field equations in five-dimensional minimal gauged supergravity and present their analytical solutions in terms of Weierstrass elliptic functions. We study the polar and radial motion, depending on the black hole and test particle parameters, and characterize the test particle motion qualitatively by means of effective potentials. We use the analytical solutions in order to visualize the test particle motion by two- and three-dimensional plots.
QUARK-CLUSTER STARS: HINTS FROM THE SURFACE

The matter inside pulsar-like compact stars could be in a quark-cluster phase since in cold dense matter at a few nuclear densities (ρ ~ 2 - 10ρ0), quarks could be coupled still very strongly and condensate in position space to form quark clusters. Quark-cluster stars are chromatically confined and could initially be bare, therefore the surface properties of quark-cluster stars would be quite different from that of conventional neutron stars. Some facts indicate that a bare and self-confined surface of pulsar-like compact stars might be necessary in order to naturally understand different observational manifestations. On one hand, as for explaining the drifting sub-pulse phenomena, the binding energy of particles on pulsar surface should be high enough to produce vacuum gaps, which indicates that pulsar's surface might be strongly self-confined. On the other hand, a bare surface of quark-cluster star can overcome the baryon contamination problem of γ-ray burst as well as promote a successful core-collapse supernova. What is more, the non-atomic thermal spectra of dead pulsars may indicate also a bare surface without atmosphere, and the hydro-cyclotron oscillation of the electron sea above the quark-cluster star surface could be responsible for those absorption features detected. These hints could reflect the property of compact star's surface and possibly the state of condensed matter inside, and then might finally result in identifying quark-cluster stars.
Microsoft Word-IASv5

The uncoordinated charging of electric vehicles (EVs) leads to either distribution transformer overload and accelerated aging or requires asset upgrade to a larger transformer to accommodate the peak charging demand. The situation can be further exacerbated under very fast EV charging due to higher peak-to-average load ratio. This paper proposes a new charging management strategy for EV fast-charging stations to mitigate the transformer aging and reduce the operating cost. The proposed strategy uses EVs in the parking lot that do not need to be charged or slowly charged as energy storage (ES) to smooth out the fluctuating charging power from fast-charging EVs. Comparative case studies with and without the proposed strategy are performed on a PV-ES fast-charging station to verify the effectiveness of the proposed charging management method for operating cost reduction, transformer peak loading reduction, and transformer loss of life mitigation. With the proposed strategy, the peak transformer loading reduction and the operation cost saving can be as large as 47.4% and 35.2%.
GRAVITY DARKENING AND BRIGHTENING IN BINARIES

We apply a von Zeipel gravity darkening model to corotating binaries to obtain a simple, analytical expression for the emergent radiative flux from a tidally distorted primary orbiting a point-mass secondary. We adopt a simple Roche model to determine the envelope structure of the primary, assumed massive and centrally condensed, and use the results to calculate the flux. As for single rotating stars, gravity darkening reduces the flux along the stellar equator of the primary, but, unlike for rotating stars, we find that gravity brightening enhances the flux in a region around the stellar poles. We identify a critical limiting separation beyond which hydrostatic equilibrium no longer is possible, whereby the flux vanishes at the point on the stellar equator of the primary facing the companion. For equal-mass binaries, the total luminosity is reduced by about 13% when this limiting separation is reached.
Microsoft Word-96262021004497globalcom2021_wgao.docx

A stochastic approximation technique is presented as a low-complexity approach for improving efficiency by linearizing the power amplifier (PA) with dual-level supply voltage. The coefficients of the RF predistorter are updated by using the simultaneous perturbation stochastic approximation (SPSA) algorithm to minimize the adjacent channel power ratio (ACPR) under the transmit power constraints. The PA with a low supply voltage of 2 V can improve the efficiency by reducing DC power consumption in the lower output power range compared with the PA with a fixed supply voltage of 4 V. The efficiency of the PA can be further improved by using a combination of RF predistortion technique and dual-level supply voltage PA when operating close to a saturated region without significantly causing nonlinear distortion. The simulation results show that the RF predistorter using the SPSA algorithm has a faster convergence speed in suppressing spectral regrowth and a lower complexity calculation in the predistorter coefficient adaptation. Keywords— Power amplifier (PA), radio frequency predistortion (RFPD), linearization, simultaneous perturbation stochastic approximation (SPSA), stochastic approximation, algorithm
Molecular Dynamics Study of the Mechanical Behavior of Few Layer Graphene

Atomistic simulation was performed to study the mechanical properties of few layer graphene (FLG) in conjunction with monlayer graphene (MLG) under uniaxial elongation by systematically increasing the layer number from one to six. We found that the ultimate tensile strength and strain increased in these FLGs for both zigzag and armchair-directional elongations when compared with the results of MLG. We also found that the largest increments were obtained in bi- or tri-layer graphene for all the FLG systems we studied. Using atomic stress distribution analysis, it is observed that the width of the distribution became narrower, thus the maximum stress decreased in FLG compared to MLG at respective stages of identical tensile stress. It indicates that locally-driven highly elevated atomic stress of FLG has been effectively relaxed to the atoms in other layers through cooperative interlayer interaction. This effect explains the reason for synergetic mechanical strengthening of FLG since tensile failure is critically influenced by maximum atomic stress. Furthermore, the Young's moduli were slightly smaller for all FLGs compared to MLG.
Transport evidence of robust topological surface state in BiTeCl single crystals, the first strong inversion asymmetric topological insulator

Three-dimensional (3D) topological insulators (TIs) are new forms of quantum matter that are characterized by their insulating bulk state and exotic metallic surface state, which hosts helical Dirac fermions1-2. Very recently, BiTeCl, one of the polar semiconductors, has been discovered by angle-resolved photoemission spectroscopy to be the first strong inversion asymmetric topological insulator (SIATI). In contrast to the previously discovered 3D TIs with inversion symmetry, the SIATI are expected to exhibit novel topological phenomena, including crystalline-surface-dependent topological surface states, intrinsic topological p-n junctions, and pyroelectric and topological magneto-electric effects3. Here, we report the first transport evidence for the robust topological surface state in the SIATI BiTeCl via observation of Shubnikov-de Haas (SdH) oscillations, which exhibit the 2D nature of the Fermi surface and pi Berry phase. The n = 1 Landau quantization of the topological surface state is observed at B . 12 T without gating, and the Fermi level is only 58.8 meV above the Dirac point, which gives rise to small effective mass, 0.055me, and quite large mobility, 4490 cm2s-1. Our findings will pave the way for future transport exploration of other new topological phenomena and potential applications for strong inversion asymmetric topological insulators.
Three lectures: NEMD, SPAM, and shockwaves

We discuss three related subjects well suited to graduate research. The first, Nonequilibrium molecular dynamics or “NEMD”, makes possible the simulation of atomistic systems driven by external fields, subject to dynamic constraints, and thermostated so as to yield stationary nonequilibrium states. The second subject, Smooth Particle Applied Mechanics or “SPAM”, provides a particle method, resembling molecular dynamics, but designed to solve continuum problems. The numerical work is simplified because the SPAM particles obey ordinary, rather than partial, differential equations. The interpolation method used with SPAM is a powerful interpretive tool converting point particle variables to twice‐differentiable field variables. This interpolation method is vital to the study and understanding of the third research topic we discuss, strong shockwaves in dense fluids. Such shockwaves exhibit stationary far‐from‐equilibrium states obtained with purely reversible Hamiltonian mechanics. The SPAM interpolation met.
A Neat Derivation of the Representation Theorem for I (2) Processes

In this paper matrix polynomial inversion – by Laurent expansion about a second order pole – is linked to partitioned inversion of a block matrix mirroring the underlying rank assumptions. This paves the way to find closed-form solutions for the principal-part coeff icient matrices of the Laurent expansion entering the representation of I (2) processes and shaping their cointegration spaces. On this basis a neat formulation and a new proof of the representation theorem of I (2) processes are provided. * Istituto di Econometria e Matematica, Università Cattolica, Largo Gemelli 1 – 20123 Milano, Italy. E-mail: mfaliva@mi.unicatt. it, mgzoia@mi.unicatt. it