Miracle-dz/UniFAR-FTUs huggingface dataset:
Account of surface contribution to thermodynamic properties of lead selenide films

Being based on the density functional theory (DFT), computer simulation of the surface effect on thermodynamic parameters of lead selenide (PbSe) has been performed in this work. Applying the thermodynamic approach, the choice of model for the plane PbSe [200] preferred orientations has been justified, which indicates domination of the energy of surface states, while minimization of interface energy and deformation are less important in overall changing the free energy. The thermodynamic parameters for the surface of crystals and their temperature dependences in the framework of DFT method and using the hybrid functional B3LYP have been calculated, namely: energy ∆E, enthalpy ∆H, Gibbs’ free energy ∆G, isobaric heat capacities CP and isovolume heat capacities CV, entropy ∆S. The analytical expressions of temperature dependences for these thermodynamic parameters approximated using quantum-chemical calculation data have been obtained. The analysis of temperature dependences for the heat capacity corresponds to the experimental data and the Djulong–Pti law. https://doi.org/10.15407/spqeo22.02. 156 PACS 05.70. Np, 68.35. Md, 71.15. Mb
Phase Evolution and Microstructure Analysis of CoCrFeNiMo High-Entropy Alloy for Electro-Spark-Deposited Coatings for Geothermal Environment

In this work, a CoCrFeNiMo high-entropy alloy (HEA) material was prepared by the vacuum arc melting (VAM) method and used for electro-spark deposition (ESD). The purpose of this study was to investigate the phase evolution and microstructure of the CoCrFeNiMo HEA as as-cast and electro-spark-deposited (ESD) coating to assess its suitability for corrosvie environments encountered in geothermal energy production. The composition, morphology, and structure of the bulk material and the coating were analyzed using scanning electron microscopy (SEM) coupled with energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD). The hardness of the bulk material was measured to access the mechanical properties when preselecting the composition to be pursued for the ESD coating technique. For the same purpose, electrochemical corrosion tests were performed in a 3.5 wt. % NaCl solution on the bulk material. The results showed the VAM CoCrFeNiMo HEA material had high hardness (593 HV) and low corrosion rates (0.0072 mm/year), which is promising for the high wear and corrosion resistance needed in the harsh geothermal environment. The results from the phase evolution, chemical composition, and microstructural analysis showed an adherent and dense coating with the ESD technique, but with some variance in the distribution of elements in the coating. The crystal structure of the as-cast electrode CoCrFeNiMo material was identified as face centered cubic with XRD, but additional BCC and potentially σ phase was formed for the CoCrFeNiMo coating.
Discriminative Regression Machine: A Classifier for High-Dimensional Data or Imbalanced Data

We introduce a discriminative regression approach to supervised classification in this paper. It estimates a representation model while accounting for discriminativeness between classes, thereby enabling accurate derivation of categorical information. This new type of regression models extends existing models such as ridge, lasso, and group lasso through explicitly incorporating discriminative information. As a special case we focus on a quadratic model that admits a closed-form analytical solution. The corresponding classifier is called discriminative regression machine (DRM). Three iterative algorithms are further established for the DRM to enhance the efficiency and scalability for real applications. Our approach and the algorithms are applicable to general types of data including images, high-dimensional data, and imbalanced data. We compare the DRM with currently state-of-the-art classifiers. Our extensive experimental results show superior performance of the DRM and confirm the effectiveness of the proposed approach.
Professional SQL Server 2008 Internals and Troubleshooting

A hands-on resource for SQL Server 2008 troubleshooting methods and tools SQL Server administrators need to ensure that SQL Server remains running 24/7. Authored by leading SQL Server experts and MVPs, this book provides in-depth coverage of best practices based on a deep understanding of the internals of both SQL Server and the Windows operating system. You'll get a thorough look at the SQL Server database architecture and internals as well as Windows OS internals so that you can approach troubleshooting with a solid grasp of the total processing environment. Armed with this comprehensive understanding, readers will then learn how to use a suite of tools for troubleshooting performance problems whether they originate on the database server or operating system side. Topics Covered: SQL Server Architecture Understanding Memory SQL Server Waits and Extended Events Working with Storage CPU and Query Processing Locking and Latches Knowing Tempdb Defining Your Approach To Troubleshooting Viewing Server Performance with PerfMon and the PAL Tool Tracing SQL Server with SQL Trace and Profiler Consolidating Data Collection with SQLDiag and the PerfStats Script Introducing RML Utilities for Stress Testing and Trace File Analysis Bringing It All Together with SQL Nexus Using Management Studio Reports and the Performance Dashboard Using SQL Server Management Data Warehouse Shortcuts to Efficient Data Collection and Quick Analysis Note: CD-ROM/DVD and other supplementary materials are not included as part of eBook file.
IMPACT OF PVA FIBER AS FINE AGGREGATE REPLACEMENT IN ALKALI-ACTIVATED FLY ASH ON FLOW RATE, MECHANICAL PROPERTIES AND DRYING SHRINKAGE

This study focuses to discuss the performance of alkali-activated mortar (AAM) reinforced by Polyvinyl Alcohol (PVA) fiber as a replacement of fine aggregate. Drying shrinkage is a major problem of alkali-activated mortar (AAM). Therefore, in order to reduce shrinkage and improve the performance of the mortar; the Polyvinyl Alcohol (PVA) fiber was introduced to replace the fine aggregate. An experimental test, including flow rate, compressive strength, modulus elasticity, poison’s ratio, flexural strength and rate of drying shrinkage, was performed to investigate the performance of AAM with various percentage of PVA fiber. Based on the test, it was obtained that the utilization of PVA fiber as a fine aggregate replacement shows a slight decrease in the flow rate compared to plain AAM. The density of PVA AAM reinforced-fiber of five mixtures is almost similar to plain AAM with the differences lower than 2%. The use of PVA at levels ranging from 0% to 2%, with a level increment of 0.5% by volume, as fine aggregate replacement increased compressive strength, but decreased flexural strength. The replacement of fine aggregate with a certain value of PVA, which are 0.5% by volume, reduces the drying shrinkage of mortar. However, adding PVA more 0.5% by volume to the mortar increases the drying shrinkage.
On conformal spectral gap estimates of the Dirichlet–Laplacian

We study spectral stability estimates of the Dirichlet eigenvalues of the Laplacian in non-convex domains $\Omega\subset\mathbb R^2$. With the help of these estimates we obtain asymptotically sharp inequalities of ratios of eigenvalues in the frameworks of the Payne-P\'olya-Weinberger inequalities. These estimates are equivalent to spectral gap estimates of the Dirichlet eigenvalues of the Laplacian in non-convex domains in terms of conformal (hyperbolic) geometry.
Improved Apriori algorithm based on matrix

To the deficiency of Apriori algorithm, an improved Apriori algorithm based on the matrix is put forward. This algorithm converts the affair database to a matrix and operates it to find out the largest K-frequent itemsets, at last uses the matrix to find out all the other frequent itemsets from 2-frequent itemsets to K-1-frequent itemsets. Using an example shows the concrete process of the algorithm and comparing with other algorithms the advantages and disadvantages of the algorithm are expounded. This algorithm not only uses ma- trix and "AND operation" instead of the query operation in the database, but also greatly reduce the number of candidates of frequent itemsets, so the algorithm obtains the bonus time of calculating and improves the efficiency of computing.
Thermal performance augmentation of a solar flat plate collector using the shot peening technique

This article deals with the thermal-hydraulic performance of a flat plate solar collector (FPSC) whose copper absorber plate and copper tubing surface are shot-peened to increase the fatigue life, strength, and roughness through a pressurized steel grit shot peening mechanism, to enhance the performance of FPSC. The objective of this experiment is to increase the convective heat transfer coefficient (CHTC) with lowest possible pumping power by augmenting the heat transfer between the absorber plate and the heat transfer fluid. The increase in surface area of the absorber tube and absorber plate made of the copper enables an increment in a specific length for “h” from the absorber area to the heat transfer fluid; this ensures that the surface area exposed to solar irradiance is increased. The experimental results show that the maximum thermal efficiency of the shot peened FPSC was about 54.24% when the flow rate was maintained at 0.02 kg/s. The cost per liter of hot water produced using FPSC whose absorber tube and absorber plate were painted black was about US $0.3.
Lens Model and Source Reconstruction Reveal the Morphology and Star Formation Distribution in the Cool Spiral LIRG SGAS J143845.1+145407

We present Hubble Space Telescope (HST) imaging and grism spectroscopy of a strongly lensed LIRG at z = 0.816, SGAS 143845.1+145407, and use the magnification boost of gravitational lensing to study the distribution of star formation throughout this galaxy. Based on the HST imaging data, we create a lens model for this system; we compute the mass distribution and magnification map of the z = 0.237 foreground lens. We find that the magnification of the lensed galaxy ranges between 2 and 10, with a total magnification (measured over all the images of the source) of μ = . We find that the total projected mass density within ∼34 kpc of the brightest cluster galaxy is . Using the lens model we create a source reconstruction for SGAS 143845.1+145407, which, paired with a faint detection of Hα in the grism spectroscopy, allows us to finally comment directly on the distribution of star formation in a z ∼ 1 LIRG. We find widespread star formation across this galaxy, in agreement with the current understanding of these objects. However, we note a deficit of Hα emission in the nucleus of SGAS 143845.1+145407, likely due to dust extinction.
Free-particle wave function and Niederer's transformation

The solutions to the free Schroedinger equation discussed by P. Strange (arXiv: 1309.6753) and A. Aiello (arXiv: 1309.7899) are analyzed. It is shown that their properties can be explained with the help of Niederer's transformation.
Weak measurements beyond the Aharonov-Albert-Vaidman formalism

We extend the idea of weak measurements to the general case, provide a complete treatment, and obtain results for both the regime when the preselected and postselected states (PPS) are almost orthogonal and the regime when they are exactly orthogonal. We surprisingly find that for a fixed interaction strength, there may exist a maximum signal amplification and a corresponding optimum overlap of PPS to achieve it. For weak measurements in the orthogonal regime, we find interesting quantities that play the same role that weak values play in the nonorthogonal regime.
Tribological Test and Mechanical Properties of Electrodeposited Nickel Coating on the Metal Surface of Carbon Steel 4140

Wear and corrosion are the main problems in mechanical elements in mechanical contact and therefore there are economical losses. To enhance the tribological properties of the metallic materials, nickel coating has found a wide application in aerospace, automobile, chemical industries and other. In this research nickel coating on carbon steel substrate were developed using nickel sulfamate bath and Watts nickel bath to obtain homogeneous electrodeposits so as good adherence and nonporous material. Nickel is one of the most used metals in the nuclear industry as well as in conventional industry, so it is important to study its morphological composition and its mechanical properties. The crystal structure of nickel: It is distributed in two phases, gamma (γ) and gamma prime (γ›): -Gamma phase: solid solution centered on the faces that acts as a matrix. Gamma prime phase: dispersion of ordered intermetallic precipitates, responsible for the great resistance of the super-alloys. Experimental development
CompHD: Efficient Hyperdimensional Computing Using Model Compression

Hyperdimensional (HD) computing is a mathematical framework, inspired by neuroscience, which can be used to represent many machine learning (ML) problems. Data is first encoded into high dimensional space (on the order of 103 or 104 dimensions) to create hypervectors. HD computing combines these hypervectors to create a model used for inference. However, due to the high dimensionality of the hypervectors, inference in HD is very expensive, especially when it runs on embedded devices with limited resources. One naive approach to improve the efficiency of HD computing is to simply lower the dimensionality of hypervectors, which comes with a corresponding loss in accuracy. However, if the data is compressed intelligently, we can reduce the dimensionality of an HD model without sacrificing accuracy. To that end, we propose CompHD, a novel approach for compressing HD models while maintaining the accuracy of the original model. CompHD utilizes the mathematics of high-dimensional spaces to compress hypervectors into shorter vectors while maintaining the information of full length hypervectors. We evaluated the efficiency of CompHD on a variety of applications. Our results show that CompHD can reduce model size by an average of 69.7%, resulting in a execution time speed up of 4.1 × and improving energy efficiency by 74% while maintaining the accuracy of the original model. This enables more low powered IoT devices to utilize HD computing for ML problems.
Extrapolating the evolution of galaxy sizes to the epoch of reionization

We use data on the high-redshift evolution of the size distribution and luminosity function of galaxies to constrain the relationship between their star formation efficiency and starburst lifetime. Based on the derived scaling relations, we predict the angular sizes and average surface brightnesses of faint galaxies that will be discovered with JWST. We find that JWST will be able to resolve galaxies at the magnitude limit mAB < 31 out to a redshift of z ∼ 14. The next generation of large ground-based telescopes will resolve all galaxies discovered with JWST, provided they are sufficiently clumpy to enable detection above the bright thermal sky. We combine our constraints with simple models for self-regulation of star formation, and show that feedback from supernovae at redshifts z ≳ 3 is likely mediated through momentum transfer, with the starburst time-scale set by the lifetime of the massive stars rather than the dynamical time in the host galactic disc.
Elementary exciton mediated Raman scattering mechanisms in pristine and functionalized single walled carbon nanotubes

(i) 1 |Introduction . 1 2 |Exciton-phonon coupling in CNTs . 7 2.1 Theoretical background . 7 2.1. 1 Structural properties . 7 2.1. 2 Vibrational properties . 9 2.1. 3 Electronic properties . 11 2.1. 4 Excitonic properties. 13 2.1. 5 Coupled states of excitons and phonons . 16 2.1. 6 Microscopic theory of Raman scattering . 17 2.1. 7 Resonant Raman scattering in carbon nanotubes . 21 2.1. 8 Fifth-order perturbation theory . 25 2.2 Experimental methods . 29 2.2.1 Single chirality enrichment by gel permeation chromatography . 29 2.2.2 Resonant Raman spectroscopy setup . 30 2.2.3 Calibration of Raman spectra . 33 2.3 Chirality dependence of exciton-phonon coupling . 35 2.3.
WIND EXTRACTION USING SATELLITE IMAGES IN CPTEC : NEW VERSION AND EVALUATION WITH WETAMC / LBA AND OPERATIONAL DSA / CPTEC DATA

Wind fields obtained through clouds displacement observed in geostationary satellite images are important tools in the data production for assimilation in atmospheric general circulation models. This study introduces changes in the algorithm and improvements in the method in operation in CPTEC (Center for Weather Forecast and Climatic Studies). Two main improvements were implemented: a clouds semi-transparency height correction, using a new simplified radiative transfer model and a space consistency test. The radiative model performance was evaluated using calculations line by line. The entire wind derivation scheme was compared with the “state of the art” represented by the wind fields obtained by cloud displacement produced by NOAA/NESDIS, and validated through the comparison with radiosonde data obtained in the campaign WETAMC/LBA. The results show that the products obtained by the CPTEC version have a similar performance as the NOAA/NESDIS products for high tropospheric levels, while indicate the need for more efforts in the determination of middle and low level winds. This new version of the algorithm has been used operationaly in CPTEC since September 2000 and some comparisons with radiosonde data are introduced. The results showed that in an operational outline the results were worse than those obtained in campaign, due to problems found in the images and in radiosonde data.
Firing Pin Impression Segmentation using Canny Edge Detection Operator and Hough Transform

Firearms identification based on the forensic ballistics specimen is crucial in solving criminal case in a short time. Currently, the firearms examiners perform authentication by visual observation. Due to observation of large evidence database, the experts normally take a long time to identify the firearms. As a result, computerized firearms identification should be implemented in order to perform the identification faster. The computerized identification involves image preprocessing, segmentation, feature extraction and classification. Therefore, in order to reduce computational time, the segmentation has to be performed automatically. The main objective of this study is to perform the segmentation of firing pin impression by using Canny edge detection operator improvised with Hough transform. The performance of segmentation in detecting the central image of firing pin impression has achieved 93% segmentation accuracy
Synthesis of rGO via UV-assisted photocatalytic reduction of graphene oxide

We perform a novel strategy for the synthesis of reduced graphene oxide (rGO) with an 18 W UV-assisted photocatalytic reduction method. The surface morphology and internal structure of the obtained rGO were identified by Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM). The rGO electrode materials have 2-6 layers graphene layers with a thickness of 1.1 nm to 2.2 nm after the photocatalytic reduction for 10 h. The rGO shows a superb capacitance of 250.41 Fg -1 with obvious triangles in the electrochemical charge-discharge analysis, which indicates good reversibility between the graphene oxide and reduced graphene oxide. This research may provide new insights that contribute to resolving the capacity issues of lithium batteries. Copyright © 2018 VBRI Press.
A Performance Evaluation Framework for a Public University Knowledge Management System

Measuring information technology (IT) implementation success has long been a challenge for information systems researchers and practitioners. The IT evaluation problem is exacerbated when assessing the specific performance of a knowledge management system (KMS), in part because the dependent variable must measure the construct of IT driven incremental enhancements to organizational knowledge and productivity. Historically, researchers have used many quantitative and qualitative variables to evaluate the performance of IT implementations, ranging from return on investment to quality of user decision-making. Academic institutions, such as universities, often have knowledge creation as a final goal, adding to the complexity of the KMS performance measurement challenge. This paper describes a planned, multi-phased, KMS implementation at a typical state university, and presents the theoretically-based, yet practitioner-oriented measures that will be applied to evaluate the ongoing success of the KMS, as it is deployed.
Advanced AlGaAs/GaAs Heterostructures Grown by MOVPE

AlGaAs/GaAs heterostructures are the base of many semiconductor devices. The fabrication of new types of devices demands heterostructures with special features, such as large total thickness (~20 μm), ultrathin layers (~1 nm), high repeatability (up to 1000 periods) and uniformity, for which a conventional approach of growing such heterostructures is insufficient and the development of new growth procedures is needed. This article summarizes our work on the metalorganic vapour-phase epitaxy (MOVPE) growth of AlGaAs/GaAs heterostructures for modern infrared devices. The growth approaches presented allow for the improved output characteristics of different emitting devices such as multi active region lasers, epitaxially integrated via highly doped tunnel junctions (emission wavelength λ ~ 1 μm), quantum cascade lasers (λ ~10 μm) and THz laser (λ ~100 μm), based on short-period superlattice with 500–2000 layers.
CNT-polyamide nanocomposite membranes for gas and water separations

We have developed asymmetric carbon nanotube /polyamide membranes for gas sorption and desalination applications. The carbon nanotubes are functionalized with zwitterionic groups that control the sorption of gases and the rejection of ionic species while permitting the transport of water. The molecular-level events controlling the adsorption of gases and the transport of fluids through functionalized carbon nanotubes, including entrance effects have been studied using molecular dynamics. The simulations show that water signficantly changes the adsorption dynamics of gases and that ions are rejected through a combination of electrostatic and steric factors.
ANISOTROPIC LYMAN-ALPHA EMISSION

As a result of resonant scatterings off hydrogen atoms, Lyα emission from star-forming galaxies provides a probe of the (hardly isotropic) neutral gas environment around them. We study the effect of the environmental anisotropy on the observed Lyα emission by performing radiative transfer calculations for models of neutral hydrogen clouds with prescriptions of spatial and kinematic anisotropies. The environmental anisotropy leads to corresponding anisotropy in the Lyα flux and spectral properties and induces correlations among them. The Lyα flux (or observed luminosity) depends on the viewing angle and shows an approximate correlation with the initial Lyα optical depth in the viewing direction relative to those in all other directions. The distribution of Lyα flux from a set of randomly oriented clouds is skewed to high values, providing a natural contribution to the Lyα equivalent width (EW) distribution seen in observation. A narrower EW distribution is found at a larger peak offset of the Lyα line, similar to the trend suggested in observation. The peak offset appears to correlate with the line shape (full width at half-maximum and asymmetry), pointing to a possibility of using Lyα line features alone to determine the systemic redshifts of galaxies. The study suggests that anisotropies in the spatial and kinematic distributions of neutral hydrogen can be an important ingredient in shaping the observed properties of Lyα emission from star-forming galaxies. We discuss the implications of using Lyα emission to probe the circumgalactic and intergalactic environments of galaxies.