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To improve the engineering application of powder metallurgy Cu–12Al alloys in bearing workpieces, a machine learning (ML) procedure was proposed. The experimental feedback data were used to improve the ML extrapolation. Binary and ternary alloys data were used to build the ML model to predict quaternary alloys. A multi-objective express index was used to assess the comprehensiveness of the searched alloys. The experimental result of predicted alloy updates training data to search next alloy. Cu–13Al–5Fe–5Ni alloy was found to have higher tensile strength (381.6 MPa) and hardness (140.1 HB) than those of traditional Cu–12Al alloy. The microstructure indicated that the designed alloy has three precipitation phases to strengthen matrix. Further, the designed alloy has the balance between tensile strength and hardness. This work is of much practical significance in reducing trial-and-error tests to improve design efficiency for material design. [ABSTRACT FROM AUTHOR]

Sb2Te thin films were deposited on SiO2/Si (100) substrates by magnetron sputtering. We investigated the crystallization behavior of Sb2Te thin films for phase-change memory applications. The experimental results show that the optical reflectivity is increased by more than 30% before and after crystallization. The resistance is decreased at least 102 orders of magnitude in the crystallization process, which suggests the application potential of Sb2Te thin film as optoelectronic storage material. The computational results show that the local crystallization activation energy is 1.72 eV and the crystal growth velocity is 4.96 m s−1, confirming the strong crystallization tendency of Sb2Te thin film. We examined the features of amorphous local bonding and found that the local octahedral geometry is the structural origin of optoelectronic contrast and crystallization tendency. Furthermore, the presence of weak Sb-Sb, Sb-Te, and Te-Te bonds and high mobility of Sb atoms facilitate the high-speed and low-activation-energy crystallization. Hence, we suggested that reducing the number of octahedrons and introducing the strong chemical bonds could promote stable optoelectronic memory applications of Sb2Te thin film. [ABSTRACT FROM AUTHOR]

We developed a 3D rotational viscometer model based on the finite volume method and analyzed the effects of the shear rate, glass bead solid fraction, and particle size on the viscosity of water and maltose syrup. We developed a novel Gidaspow model and introduced particle sphericity as a parameter. The effects of sphericity, solid fraction, and particle size on the viscosity of different fluids were simulated and calculated. Compared with the experimental findings, the maximum relative error was 10.7% before the solid fraction was 30%, and the calculated data suitably agree with the experimental results. The results also show that when the solid fraction is above 10%, the particle fluid viscosity increases with increasing shear rate and solid fraction and decreases with increasing sphericity and particle size. The novel Gidaspow equation can suitably predict the initial apparent viscosity of different solid–liquid mixtures before reaching a solid fraction of 50%. The new model has a wide range of applications and can be applied to arbitrary particle shapes (spherical range of 0–1) in various materials and fields. The proposed model can provide a reference for further theoretical and experimental studies on solid–liquid two-phase flow. [ABSTRACT FROM AUTHOR]

A machine learning (ML) process on composition optimization was performed to design Ni-based turbine disc superalloys with improved yield strength. Based on published data of polycrystalline Ni-based superalloys, the design process is finished through regression algorithm, feature rank method, and genetic algorithm, which is simple and high-efficient to optimize composition. The two designed alloys are assessed using the Calculation of Phase Diagram (CALPHAD), finding the microstructure of both alloys according with superalloys. Comparing with commercial Ni-based turbine disc superalloys, the designed alloys have trade-offs on mechanical and physical properties. The ML architecture and the assessment results are then discussed, indicating that the design ability of ML to automatically optimize is promising. This work is of much practical significance in reducing trial-and-error test to improve design efficiency for material design, providing an effective way to development novel Ni-based turbine disc superalloys. [ABSTRACT FROM AUTHOR]

Combining the advantages of total generalized variation and wavelet transform, we propose a new hybrid model based on L 1 norm for image restoration. Numerically, we obtain the optimal solution by alternating iteration of the efficient augmented Lagrangian method. For the selection of regularization parameters, we use an adaptive criterion based on the value function. Experimental results show that the proposed algorithm can remove impulse noise well and reduce staircase effect while preserving edges. Compared with several classical methods, the proposed model has also higher PSNR and SSIM values. [ABSTRACT FROM AUTHOR]

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With scientific research in materials science becoming more data intensive and collaborative after the announcement of the Materials Genome Initiative, the need for modern data infrastructures that facilitate the sharing of materials data and analysis tools is compelling in the materials community. In this paper, we describe the challenges of developing such infrastructure and introduce an emerging architecture with high usability. We call this architecture the Materials Genome Engineering Databases (MGED). MGED provides cloud-hosted services with features to simplify the process of collecting datasets from diverse data providers, unify data representation forms with user-centered presentation data model, and accelerate data discovery with advanced search capabilities. MGED also provides a standard service management framework to enable finding and sharing of tools for analyzing and processing data. We describe MGED's design, current status, and how MGED supports integrated management of shared data and services. [ABSTRACT FROM AUTHOR]

Thousand grain weight (TGW) is an important determinant of rice yield, and correlates with grain size, plumpness and grain number per panicle. In rice, there are fewer association mapping studies relating grain weight traits using both SSR and SNP markers. In this study, in order to find robust SSR markers associated with TGW trait and mine elite accessions in rice, we investigated the TGW trait across six environments using a natural population consisted of 462 accessions, and then performed association mapping using both SSR and SNP markers. Using the six datasets from the six environments and their best linear unbiased estimator, we identified eight TGW associated SSR markers, with three environmentally stable and one newly found, on five chromosomes. The associated markers have genetic effect from 3.44% to 20.84%, and two of them carry stable elite allele with positive effect across different environments. Candidate interval association mapping using re-sequencing derived SNP/InDel markers further confirms the TGW-SSR association, and also suggests that 3 TGW-SSR associations were high confident in intervals of size from 176 to 603 kb. These results not only shed more lights on the genetics of TGW trait, but also suggest that the multi-allelic SSR markers should be used as an alternative power tool in gene or QTL mapping. [ABSTRACT FROM AUTHOR]

The C-Mo-Zr system was assessed by means of the CALPHAD approach. All of the phase equilibria available from the literature were critically reviewed. The liquid was modeled as substitutional solution phase, while the carbides including fcc-(Mo,Zr)C1−x, bcc-(Mo), bcc-(Zr), hcp-Mo2C, hcp-(Zr) and η-MoC were described by using corresponding sublattice models. The laves-Mo2Zr and shp-MoC phases were considered as binary compounds with no solubility for the third component. The existence of ternary phase was not reported in this system. The modeling of C-Mo-Zr ternary system covers the entire composition and temperature ranges, and a set of self-consistent thermodynamic parameters for the C-Mo-Zr system was systematically optimized. Comprehensive comparisons between the calculated and reported phase diagram data show that the reliable information is satisfactorily accounted for by the present modeling. The liquidus projection and reaction scheme of the C-Mo-Zr system were also generated based on the present thermodynamic assessment. [ABSTRACT FROM AUTHOR]

Image inpainting in the wavelet domain refers to the recovery of an image from incomplete wavelet coefficients. In this paper, we propose a wavelet inpainting model by using fractional order total variation regularization approach. Moreover, we use a simple but very efficient primal-dual algorithm to calculate the optimal solution. In the light of saddle-point theory, the convergence of new algorithm is guaranteed. Experimental results are presented to show performance of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Novel microwave dielectric ceramic YZnAlSiO were synthesized by solid-state route. The crystal structure of synthesized samples was characterized by X-ray diffraction and refined with Rietveld method. Microstructure and microwave dielectric properties of YZnAlSiO ceramics were investigated using Scanning Electron Microscopy and Hakki-Coleman method. X-ray data display that major phase of YZnAlSiO is isostructural to YAlO with a cubic garnet structure and space group of Ia-3d, which is composed of (Al/Si)O tetrahedron, (Zn/Al)O octahedron and YO dodecahedron, besides minor YSiO secondary phase. The distribution of grain sizes is closer to Gauss distribution. Bulk density of samples has a similar variation curve with Q* f of samples. YZnAlSiO ceramics exhibit excellent microwave dielectric properties: ε = 10.2, Q* f = 37938.2 (@9.47 GHz), τ = −31.7 ppm/°C at sintering temperature of 1500 °C. Our results indicate YZnAlSiO could be a potential material for millimeter wave communication systems as microwave substrates. [ABSTRACT FROM AUTHOR]

A novel flame retardant (PSiN), containing silicon and nitrogen, was synthesized using N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane (KH-602) and diphenylsilanediol through solution polycondesation and it was used together with potassium-4-(phenylsulfonyl)benzenesulfonate (KSS) to prepare a flame-retardant system for polycarbonate (PC). The structure and thermal property of PSiN were characterized by Fourier transform infrared spectroscopy (FTIR), HNMR and thermogravimetric analysis (TG) tests. Flammability and thermal behaviors of PC/KSS/PSiN systems were estimated by limited oxygen index (LOI), cone calorimeter, vertical burning test (UL-94), and TG tests. The results showed that the flame retardancy and char residues of PC/KSS system were improved with the addition of PSiN. When 1 mass% PSiN and 0.5 mass% KSS were incorporated, the LOI value of PC was found to be 46, and class V-0 of the UL-94 test. Moreover, both the heat release rate and the total heat release of PC/KSS/1 mass% PSiN decreased compared with those of PC and PC/KSS systems. The microstructures observed by scanning electron microscopy and FTIR indicated that the surface of the char for PC/KSS/PSiN system hold a more cohesive and denser char structure when compared with the pure PC and PC/KSS system. [ABSTRACT FROM AUTHOR]

A novel flame retardant (PSiN), containing silicon and nitrogen, was synthesized using N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane and diphenylsilanediol through solution polycondensation and it was added to polycarbonate (PC). The structure and thermal properties of PSiN were characterized by fourier transform infrared spectroscopy and thermogravimetric analysis (TG) tests. The effect of PSiN on the flame retardancy and thermal behaviors of PC was investigated by limited oxygen index (LOI), vertical burning test (UL-94), and TG tests. The results showed that the flame retardancy and the thermal stability of PC are improved with the addition of PSiN. When 1 mass% PSiN and 0.5 mass% diphenylsulfone sulfonate (KSS) are incorporated, the LOI value of PC is found to be 46, and class V-0 of UL-94 test is passed. The char structure observed by scanning electron microscopy indicated that the surface of the char for PC/KSS/PSiN system holds a firmer and denser char structure when compared with neat PC and PC/KSS system. [ABSTRACT FROM AUTHOR]

In this article, the laboratory-made poly ( p-ethylene terephthalamide) (PETA) was used as a novel charring agent and it combined with ammonium polyphosphate (APP) to prepare the intumescent flame retardant (IFR). For improving the flame-retardant efficiency of IFRs on polypropylene (PP), several general synergistic agents, such as common zinc oxide (Com-ZnO), nanometer structural zinc oxide (Nano-ZnO), zeolite 4A, and aluminum hypophosphite(Al(HPO)), were added in composites of PP/IFR, and the synergistic effect was investigated by the limited oxygen index (LOI), the UL-94 (vertical flame) test, thermogravimetric analysis (TG), thermogravimetry-fourier transform infraredspectroscopy (TG-IR) test, and scanning electron microscopy (SEM). It indicated that the flame retardancy was significantly enhanced in terms of prompting the char formation of PETA and interaction between APP and synergistic agents. Overall, Al(HPO) was the most effective synergistic agent among them. TG-IR analysis showed that the addition of Al(HPO) could delay the release of NH, and make the release of NH more smooth, which was useful to form a dense char. SEM presented that compact, continuous and good intumescent charring layers were observed in all PP/IFR systems with synergistic agent. [ABSTRACT FROM AUTHOR]

Sparse nonnegative matrix factorizations can be considered as dimension reduction methods that can control the degree of sparseness of basis matrix or coefficient matrix under non-negativity constraints. In this paper, by exploring the sparsity of the basis matrix and the coefficient matrix under certain domains, we propose an alternative iteration approach with l-norm minimization for face recognition. Moreover, a modified version of linearized Bregman iteration is developed to efficiently solve the proposed minimization problem. Experimental results show that new algorithm is promising in terms of detection accuracy, computational efficiency. [ABSTRACT FROM AUTHOR]

The main aim of this paper is to accelerate the image decomposition model based on ( BV, H). It is solved with a particularly effective primal-dual gradient descent algorithm. The algorithm works on the primal-dual formulation and exploits the information of the primal and dual variables simultaneously. It converges significantly faster than some popular existing methods in numerical experiments. This approach is to some extent related to projection type methods for solving variational inequalities. [ABSTRACT FROM AUTHOR]

Micro powder injection molding (μPIM), a miniaturized variant of powder injection molding, has advantages of shape complexity, applicability to many materials and good mechanical properties. Co-injection molding has been realized between metals and ceramics on micro components, which become the first breakthrough within the PIM field. Combined with the prominent characteristics of high features/cost ratio, micro powder injection molding becomes a potential technique for large scale production of intricate and three-dimensional micro components or microstructured components in microsystems technology (MST) field. [ABSTRACT FROM AUTHOR]

In this paper, a new method which combines the basis pursuit denoising algorithm (BPDN) and the total variation (TV) regularization scheme is presented for separating images into texture and cartoon parts. It is a modification of the model [1]. In this process, two appropriate dictionaries are used, one for the representation of texture parts-the dual tree complex wavelet transform (DT CWT) and the other for the cartoon parts-the second generation of curvelet transform. To direct the separation process and reduce the pseudo-Gibbs phenomenon, the curvelet transform is followed by a projected regularization method for cartoon parts. Experimental results show that new method cannot only decompose better for a given image but also reduce the runtime, in comparison to the MCA approach. [ABSTRACT FROM AUTHOR]