250 research outputs found
freeQuant: A Mass Spectrometry Label-Free Quantification Software Tool for Complex Proteome Analysis
Bond-based nonlocal models by nonlocal operator method in symmetric support domain
This paper is concerned with the energy decomposition of various nonlocal
models, including elasticity, thin plates, and gradient elasticity, to arrive
at bond-based nonlocal models in which the bond force depends only on the
deformation of a single bond. By assuming an appropriate form of bond force and
using energy equivalence between local and nonlocal models, several very
concise bond-based models are derived. We also revisit the nonlocal operator
methods and study the simplified form of second-order NOM in the symmetric
support domain. A bent-bond consisting of three points is proposed to describe
the curvature and moment. To model the damage, a rule based on Griffith theory
for the critical normal strain of the bond is proposed in analogy to the phase
field model, which can be applied individually to each bond and provides strain
localization. With this rule, the crack direction can be automatically
predicted by simply cutting the bond, giving comparable results to the phase
field method. At the same time, a damage rule for critical shear strains in
shear fractures is proposed. Furthermore, an incremental form of the plasticity
model for bond reaction force is derived. Several numerical examples are
presented to further validate the nonlocal bond-based models
Predictive maintenance for the heated hold-up tank
We present a numerical method to compute an optimal maintenance date for the
test case of the heated hold-up tank. The system consists of a tank containing
a fluid whose level is controlled by three components: two inlet pumps and one
outlet valve. A thermal power source heats up the fluid. The failure rates of
the components depends on the temperature, the position of the three components
monitors the liquid level in the tank and the liquid level determines the
temperature. Therefore, this system can be modeled by a hybrid process where
the discrete (components) and continuous (level, temperature) parts interact in
a closed loop. We model the system by a piecewise deterministic Markov process,
propose and implement a numerical method to compute the optimal maintenance
date to repair the components before the total failure of the system.Comment: arXiv admin note: text overlap with arXiv:1101.174
Halide-Assisted Atmospheric Pressure Growth of Large WSe2 and WS2 Monolayer Crystals
Chemical vapor deposition (CVD) of two-dimensional (2D) tungsten
dichalcogenide crystals requires steady flow of tungsten source in the vapor
phase. This often requires high temperature and low pressure due to the high
sublimation point of tungsten oxide precursors. We demonstrate atmospheric
pressure CVD of WSe2 and WS2 monolayers at moderate temperatures (700 ~ 850 oC)
using alkali metal halides (MX where M= Na or K and X=Cl, Br or I) as the
growth promoters. We attribute the facilitated growth to the formation of
volatile tungsten oxyhalide species during growth, which leads to efficient
delivery of the precursor to the growth substrates. The monolayer crystals were
found to be free of unintentional doping with alkali metal and halogen atoms.
Good field-effect transistor (FET) performances with high current on/off ratio
~10 7, hole and electron mobilities up to 102 and 26 cm2 V 1 s-1 for WSe2 and
electron mobility of ~14 cm2 V-1 s-1 for WS2 devices were achieved.Comment: 21 pages, 4 figures in manuscript & 10 pages, 6 figures in
supplementary materia
Patients\u27 Acceptance of Smartphone Health Technology for Chronic Disease Management: A Theoretical Model and Empirical Test
Les quatre textes ont en commun de présenter certaines évolutions récentes de l’histoire politique en Allemagne. Ils prennent tous position face à trois tournants historiographiques. La notion d’histoire culturelle du politique peut servir d’emblème au premier de ces tournants : le politique est envisagé non plus comme une succession d’événements ni comme le fruit de déterminations structurelles dont il serait la superstructure ou l’écume, mais comme l’expression de valeurs et de procédures o..
A novel method for determining the neutral axis position of the asymmetric cross section and its application in the simplified progressive collapse method for damaged ships
Ultimate strength is an important design consideration for the safety of intact or damaged ship structures. The simplified progressive collapse method is a commonly used iterative method to obtain the accurate ultimate strength of ships. Since the accuracy of the neutral axis position directly affects the accuracy of the ultimate strength, the force equilibrium criterion and the force vector equilibrium criterion are adopted to search for the height and angle of the neutral axis, especially for damaged ships. However, the search for the neutral axis position based on the two criteria requires iterative computation which decreases the calculation efficiency. In this paper, the relationship between the results of the iterative process and the neutral axis position is studied, and it is found that the relationship is approximately linear. Then a new iterative method based on the linear equation is proposed to obtain the neutral axis position and is adopted to improve the simplified progressive collapse method. Finally, the new method is used to calculate the neutral axis position of a damaged VLCC. The comparison of the ultimate strength results shows that the improved simplified progressive collapse method based on the linear equation has improved efficiency and good accuracy
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