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1. Experimental and numerical evaluation of effects of kidney-shape carbon fiber on transverse cracking of carbon fiber reinforced plastics

Author:
Youzou Kitagawa; Akinori Yoshimura; Masahiro Arai; Keita Goto; Naoki Sugiura
Source:
Composites 2022 v.152 pp. 106690
ISSN:
1359-835X
Subject:
mathematics and statistics,   etc   ; carbon fibers; composite materials; cracking; monitoring; plastics; static testing;     Show all 7 Subjects
Abstract:
... This study aims to investigate the effects of fiber cross-sectional shape on the trans- verse crack extension of carbon fiber reinforced plastics (CFRP) both experimentally and numerically. Kidney-shape carbon fiber was compared with the laminates using conventional round-shape carbon fiber by monitoring the transverse crack accumu- lation behavior during static tensile tests. The experimental res ...
DOI:
10.1016/j.compositesa.2021.106690

2. Effects of starlike control discs on flow structures and combustion capability

Author:
Shun-Chang Yen; Cheng-En Ye; Kuo-Ching San
Source:
Energy 2021 v.225 pp. 120276
ISSN:
0360-5442
Subject:
mathematics and statistics,   etc   ; air; carbon dioxide; combustion; energy; photographs; propane; turbulent flow;     Show all 8 Subjects
Abstract:
... The mixing efficiency between the air and fuel play an important role in the combustion capability. The flow structures behind a conventional nozzle were modulated using circular, three-pointed-starlike, and six-pointed-starlike control discs to investigate the characteristic flow behaviors, mixing ability, and combustion capability. The starlike tips generated flow eddies that strengthened the re ...
DOI:
10.1016/j.energy.2021.120276

3. Exploring unusual temperature-dependent optical properties of graphite single crystal by spectroscopic ellipsometry

Author:
Desman Perdamaian Gulo; Nguyen Tuan Hung; Tan-Ju Yang; Guo-Jiun Shu; Riichiro Saito; Hsiang-Lin Liu
Source:
Carbon 2022 v.197 pp. 485-493
ISSN:
0008-6223
Subject:
mathematics and statistics,   etc   ; absorption; ambient temperature; energy; graphene; photons; silicon; spectral analysis; spectroscopy;     Show all 9 Subjects
Abstract:
... This study investigated the optical properties of graphite single crystal as a function of temperature between 4.5 and 500 K and within the spectral range of 0.73–6.42 eV through spectroscopic ellipsometry. At room temperature, the complex dielectric function of graphite exhibited broad spectra in the ultraviolet energy region. The Breit–Wigner–Fano (BWF) line shape analysis of the optical absorpt ...
DOI:
10.1016/j.carbon.2022.06.032

4. The Concept of Ontogenesis Polyvariance and Modern Evolutionary Morphology

Author:
A. A. Notov; L. A. Zhukova
Source:
Biology bulletin of the Russian Academy of Sciences 2019 v.46 no.1 pp. 47-55
ISSN:
1062-3590
Subject:
mathematics and statistics,   etc   ; ontogeny; phenotype;     Show all 3 Subjects
Abstract:
... The possibilities of using the concept of ontogeny polyvariance in evolutionary morphology are considered. The concept is aimed at identifying the full range of options associated with various aspects concerning the organization of living organisms. In conjunction with the analysis of the correlation structure of traits and methods of population meronomy, the proposed approach can help to elucidat ...
DOI:
10.1134/S1062359019010072

5. Integrating engineered point spread functions into the phasor-based single-molecule localization microscopy framework

Author:
Koen J.A. Martens; Abbas Jabermoradi; Suyeon Yang; Johannes Hohlbein
Source:
Methods 2021 v.193 pp. 107-115
ISSN:
1046-2023
Subject:
mathematics and statistics,   etc   ; computer software; fluorescent dyes; image analysis; microscopy; signal-to-noise ratio;     Show all 6 Subjects
Abstract:
... In single-molecule localization microscopy (SMLM), the use of engineered point spread functions (PSFs) provides access to three-dimensional localization information. The conventional approach of fitting PSFs with a single 2-dimensional Gaussian profile, however, often falls short in analyzing complex PSFs created by placing phase masks, deformable mirrors or spatial light modulators in the optical ...
DOI:
10.1016/j.ymeth.2020.07.010

6. Analysing the porous structure of packed beds of spheres using a semi-analytical approach

Author:
Charl G. du Toit
Source:
Powder technology 2019 v.342 pp. 475-485
ISSN:
0032-5910
Subject:
mathematics and statistics,   etc   ; equipment performance; porosity; powders;     Show all 4 Subjects
Abstract:
... In this paper methodologies are described for the analysis of the porous structure of cylindrical and annular packed beds consisting of spheres when the coordinates and sizes of the spheres are known. Methodologies to determine the overlap between adjacent spheres and between the spheres and the walls of the container; axial variation in the porosity and hydraulic diameter; and the radial variatio ...
DOI:
10.1016/j.powtec.2018.10.017

7. Resilient supplier selection and segmentation in grey environment

Author:
Sahar Valipour Parkouhi; Abdolhamid Safaei Ghadikolaei; Hamidreza Fallah Lajimi
Source:
Journal of cleaner production 2019 v.207 pp. 1123-1137
ISSN:
0959-6526
Subject:
mathematics and statistics,   etc   ; economic analysis; globalization; supply chain;     Show all 4 Subjects
Abstract:
... Supplier management is one of the complex, sensitive and multifaceted measures in supply chain that has the most effect on the successful performance of a supply chain. Selection, segmentation and development of the supplier are three important parts of supplier management. With globalization and increasing disruption and vulnerability of supply chain, the resilience of all components of supply ch ...
DOI:
10.1016/j.jclepro.2018.10.007

8. Quantum Effects on H₂ Diffusion in Zeolite RHO: Inverse Kinetic Isotope Effect for Sieving

Author:
Lu Gem Gao; Rui Ming Zhang; Xuefei Xu; Donald G. Truhlar
Source:
Journal of the American Chemical Society 2019 v.141 no.34 pp. 13635-13642
ISSN:
1520-5126
Subject:
mathematics and statistics,   etc   ; deuterium; energy; isotopes; quantum mechanics; sieving; temperature; zeolites;     Show all 8 Subjects
Abstract:
... We use canonical variational theory (CVT) with small-curvature tunneling (SCT) contributions to investigate quantum effects on the H₂ diffusion process in the pure-silica zeolite RHO. At low temperature we find an inverse kinetic isotopic sieving effect in that the heavier isotopic species diffuses faster than the lighter one. Three quantum effects contribute to this kinetic isotope effect (KIE). ...
DOI:
10.1021/jacs.9b06506

9. Attentional bias in the radial and vertical dimensions of space

Author:
Sergio Chieffi; Clara Castaldi; Girolamo Di Maio; Marco La Marra; Antonietta Messina; Vincenzo Monda; Ines Villano
Source:
Comptes rendus 2019 v.342 no.3-4 pp. 97-100
ISSN:
1631-0691
Subject:
mathematics and statistics,   etc   ; cognition; humans;     Show all 3 Subjects
Abstract:
... Under visual guidance, healthy subjects usually misbisect radial lines farther than, and vertical lines above the true center. It was suggested that radial and vertical misbisection depended on the presence of an attentional bias toward far/upper space. The aim of the present study was to investigate whether such attentional bias depends on a single mechanism or on separate mechanisms. Ninety part ...
DOI:
10.1016/j.crvi.2019.03.003

10. Effect of movement direction on resistance force in granular media

Author:
Chuanping Liu; Hongmei Wan; Li Wang
Source:
Powder technology 2019 v.344 pp. 545-550
ISSN:
0032-5910
Subject:
mathematics and statistics,   etc   ; granules; gravity; powders;     Show all 4 Subjects
Abstract:
... In this study, a cylinder is horizontally immersed in granular media and moved toward different directions. The cylinder experiences a maximum force (Fm) when plunging downward and a minimum force when pulling upward. As the cylinder moves angularly, the force (F) gradually decreases with increasing angle between the cylinder movement direction and gravity (θ). F/Fm behaves similar to a Boltzmann ...
DOI:
10.1016/j.powtec.2018.12.023

11. The Adding-Up Test in an Incentivized Value Elicitation Mechanism: The Role of the Income Effect

Author:
Levan Elbakidze; Rodolfo M. Nayga Jr.
Source:
Environmental and resource economics 2018 v.71 no.3 pp. 625-644
ISSN:
0924-6460
Subject:
mathematics and statistics,   etc   ; economic analysis; income;     Show all 3 Subjects
Abstract:
... In the context of testing the construct validity of stated preference studies, some researchers advocate the use of an “adding-up test” designed to gauge whether elicited values are sufficiently sensitive to a change in the scope (i.e. size) of a good. Crucial to the applicability of this test in practice, which relies on endowing a subsample of respondents with a good free of charge, is that the ...
DOI:
10.1007/s10640-017-0177-9

12. A simple method for particle shape generation with spherical harmonics

Author:
Deheng Wei; Jianfeng Wang; Budi Zhao
Source:
Powder technology 2018 v.330 pp. 284-291
ISSN:
0032-5910
Subject:
mathematics and statistics,   etc   ; mechanics; particle size; powders;     Show all 4 Subjects
Abstract:
... The increasing interest in particle shape influence on granular mechanics necessitates a fast and robust particle shape generation method. We describe a new approach based on rotation-invariant spherical harmonic (SH) analysis. The core of this method is to construct morphology features at various length scales and superimpose them together to form the overall morphology. This method uses four rot ...
DOI:
10.1016/j.powtec.2018.02.006

13. Force-Induced Dissolution of Imaginary Mode in Mechanochemical Reaction: Dibenzophenazine Synthesis

Author:
Naoki Haruta; Paulo Filho Marques de Oliveira; Tohru Sato; Kazuyoshi Tanaka; Michel Baron
Source:
Journal of physical chemistry 2019 v.123 no.35 pp. 21581-21587
ISSN:
1932-7455
Subject:
mathematics and statistics,   etc   ; catalytic activity; chemical bonding; density functional theory; forces; mechanochemistry; reaction mechanisms;     Show all 7 Subjects
Abstract:
... Dibenzophenazine was recently synthesized mechanochemically at a high yield. On the basis of experimental kinetics and theoretical vibronic coupling density analysis, this efficient synthesis has been expected to involve two types of reaction mechanisms. In this study, the reaction pathways, including the catalytic effect of water, are determined using density functional theory. The lowest-energy ...
DOI:
10.1021/acs.jpcc.9b05582

14. Characterization and analysis of the aspect ratio of carbide grains in WC–Co composites

Author:
Xiaokun Yuan; Yuan Ji
Source:
RSC advances 2018 v.8 no.60 pp. 34468-34475
ISSN:
2046-2069
Subject:
mathematics and statistics,   etc   ; anisotropy; carbides; mechanical properties;     Show all 4 Subjects
Abstract:
... To study the aspect ratio distribution of carbide grains in WC–Co composites, two novel approaches, namely grain shape ellipse calculation and five parameter analysis (FPA) methods, are reported in this work. According to grain shape ellipse calculation, carbide grains that have a grain shape aspect ratio of 0.62 demarcate the more anisotropic grains with a larger size and the less anisotropic gra ...
DOI:
10.1039/c8ra03186j

15. An auxiliary adaptive Gaussian mixture filter applied to flowrate allocation using real data from a multiphase producer

Author:
Rolf J. Lorentzen; Andreas S. Stordal; Neal Hewitt
Source:
Computers and Geosciences 2017 v.102 pp. 34-44
ISSN:
0098-3004
Subject:
mathematics and statistics,   etc   ; oils; temperature; wells;     Show all 4 Subjects
Abstract:
... Flowrate allocation in production wells is a complicated task, especially for multiphase flow combined with several reservoir zones and/or branches. The result depends heavily on the available production data, and the accuracy of these. In the application we show here, downhole pressure and temperature data are available, in addition to the total flowrates at the wellhead. The developed methodolog ...
DOI:
10.1016/j.cageo.2017.02.003

16. Granular jet composed of elliptical particles impacting a fixed target

Author:
Dong Su; Y.X. Wang; Yrjö Jun Huang; Attila Michael Zsaki
Source:
Powder technology 2017 v.313 pp. 303-311
ISSN:
0032-5910
Subject:
mathematics and statistics,   etc   ; glass; powders; temperature;     Show all 4 Subjects
Abstract:
... It was reported that a sheet-like or cone-like shock forms when a granular jet, composed of spherical glass beads impacts a fixed target. The discrete element method (DEM) was employed to simulate this process using elliptical particles, which were approximated by using the glued-particle method (GPM).In comparison with circular particles, our simulations show that the aspect ratio does not affect ...
DOI:
10.1016/j.powtec.2017.01.094

17. Local histogram and discriminative learning-based hyperspectral data classification

Author:
Maryam Imani; Hassan Ghassemian
Source:
Remote sensing letters 2017 v.8 no.1 pp. 86-95
ISSN:
2150-7058
Subject:
mathematics and statistics,   etc   ; hyperspectral imagery; models; remote sensing;     Show all 4 Subjects
Abstract:
... A spectral–spatial hyperspectral image classification method is proposed in this article. The proposed method is local histogram and discriminative based classification (LHD). It is implemented in two steps. In the first step, a projection matrix is obtained by maximizing the class discrimination and preserving the local structure of data using both the spectral and spatial neighbours. In the seco ...
DOI:
10.1080/2150704X.2016.1232868

18. Kernel one-class weighted sparse representation classification for change detection

Author:
Qiong Ran; Wei Li; Qian Du
Source:
Remote sensing letters 2018 v.9 no.6 pp. 597-606
ISSN:
2150-7058
Subject:
mathematics and statistics,   etc   ; data collection; remote sensing; system optimization;     Show all 4 Subjects
Abstract:
... In this letter, improved methods based on one-class sparse representation classifier (OCSRC) are proposed for change detection with multi-temporal multi-spectral remote sensing images. By adopting the weighted regularization and the kernel method, kernel one-class sparse representation classifier (K-OCSRC), one-class weighted sparse representation classifier (OCWSRC) and its kernel version, kernel ...
DOI:
10.1080/2150704X.2018.1452063

19. Regional clustering-based spatial preprocessing for hyperspectral unmixing

Author:
Xiang Xu; Jun Li; Changshan Wu; Antonio Plaza
Source:
Remote sensing of environment 2018 v.204 pp. 333-346
ISSN:
0034-4257
Subject:
mathematics and statistics,   etc   ; computer analysis; hyperspectral imagery; remote sensing;     Show all 4 Subjects
Abstract:
... Hyperspectral unmixing is an important technique for remote sensing image exploitation. It aims to decompose a mixed pixel into a collection of spectrally pure components (called endmembers), and their corresponding proportions (called fractional abundances). In recent years, many studies have revealed that unmixing using spectral information alone does not sufficiently incorporate the spatial inf ...
DOI:
10.1016/j.rse.2017.10.020

20. Division of Ferrofluid Drops Induced by a Magnetic Field

Author:
Carlo Rigoni; Stefano Bertoldo; Matteo Pierno; Delphine Talbot; Ali Abou-Hassan; Giampaolo Mistura
Source:
Langmuir 2018 v.34 no.33 pp. 9762-9767
ISSN:
1520-5827
Subject:
mathematics and statistics,   etc   ; droplets; magnetic fields; magnetic materials; wettability;     Show all 5 Subjects
Abstract:
... We report a comprehensive study of the division of ferrofluid drops caused by their interaction with a permanent magnet. As the magnet gradually approaches the sessile drop, the drop deforms into a spiked cone and then divides into two daughter droplets. This process is the result of a complex interplay between the polarizing effect caused by the magnetic field and the magnetic attraction due to t ...
DOI:
10.1021/acs.langmuir.8b02399