Comparison of one-parameter and two-parameter models of aerosol extinction for experimental data of the arid zone of Kazakhstan

2015 ◽  
Author(s):  
N. N. Shchelkanov
Keyword(s):  
Experimental Data ◽  
Arid Zone ◽  
Aerosol Extinction ◽  
Two Parameter

Light-Induced Metastable Defects or Light-Induced Metastable H Atoms in a-Si:H Films?

1997 ◽  
Vol 467 ◽  
Author(s):  
C. Godet
Keyword(s):  
Experimental Data ◽  
Characteristic Time ◽  
Defect Density ◽  
Hydrogenated Amorphous Silicon ◽  
Exponential Time ◽  
Mobile Species ◽  
Hydrogenated Amorphous ◽  
Two Parameter ◽  
Metastable Defect ◽  
Trapping Sites

ABSTRACTIn hydrogenated amorphous silicon (a-Si:H) films, the increase of the metastable defect density under high-intensity illumination is usually described by an empirical two-parameter stretched-exponential time dependence (characteristic time τSE and dispersion parameter β). In this study, a clearly different (one-parameter) analytic function is obtained from a microscopic model based on the formation of metastable H (MSH) atoms in a-Si:H films. Assuming that MSH atoms are the only mobile species, only three chemical reactions are significant : MSH are produced from doubly hydrogenated (SiH HSi) configurations and trapped either at broken bonds or Si-H bonds, corresponding respectively to light-induced annealing (LIA) and light-induced creation (LIC) of defects. Competition between trapping sites results in a saturation of N(t) at a steady-state value Nss. A one-parameter fit of this analytical function to experimental data is generally good, indicating that the use of a statistical distribution of trap energies is not necessary.

scholarly journals Some New Fractional-Calculus Connections between Mittag–Leffler Functions

Mathematics ◽  
2019 ◽  
Vol 7 (6) ◽  
pp. 485 ◽  
Author(s):  
Hari M. Srivastava ◽  
Arran Fernandez ◽  
Dumitru Baleanu
Keyword(s):  
Experimental Data ◽  
Fractional Calculus ◽  
Fractional Derivative ◽  
Fractional Integral ◽  
Integral Expression ◽  
Potential Applications ◽  
The One ◽  
Two Parameter

We consider the well-known Mittag–Leffler functions of one, two and three parameters, and establish some new connections between them using fractional calculus. In particular, we express the three-parameter Mittag–Leffler function as a fractional derivative of the two-parameter Mittag–Leffler function, which is in turn a fractional integral of the one-parameter Mittag–Leffler function. Hence, we derive an integral expression for the three-parameter one in terms of the one-parameter one. We discuss the importance and applications of all three Mittag–Leffler functions, with a view to potential applications of our results in making certain types of experimental data much easier to analyse.

The Experiment for the Fracture Toughness of the Compound Bioceramic and the Analysis for the Confidence Level of its Reliability

2010 ◽  
Vol 44-47 ◽  
pp. 3003-3010
Author(s):  
Shi Lian Xu ◽  
Rui Hong Wang ◽  
Ruo Qi Li ◽  
Ren Ping Xu
Keyword(s):  
Experimental Data ◽  
Fracture Toughness ◽  
Confidence Level ◽  
Confidence Limit ◽  
Limit Curve ◽  
Medical Treatments ◽  
Manufacturing Method ◽  
Upper Confidence Limit ◽  
Lower Confidence ◽  
Two Parameter

The brittle is crippling the application of bioceramic. The compound bioceramic is a new biomaterial being widely applied in medical treatments and its fracture toughness is an important mechanical behaviors. In this paper, we introduce the manufacturing method of the compound bioceramic and experiment facilities for its fracture toughness, investigate its probability distribution for the experimental data and conduct the test for fit. We conclude that the experimental data for the toughness fracture of the compound bioceramic obey the two-parameter Weibull distribution, introduce the analyzing method for the upper confidence limit curve and lower confidence limit curve and study the reliability and confidence level of the fracture toughness of the compound bioceramic.

Similarity Solution for the Curved Two-Dimensional Jet

1972 ◽  
Vol 39 (4) ◽  
pp. 879-882
Author(s):  
G. K. Fleming ◽  
S. A. Alpay
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Nonlinear Equation ◽  
Similarity Solution ◽  
Separation Bubble ◽  
The Other ◽  
Wall Jet ◽  
Two Dimensional ◽  
Two Parameter ◽  
Outer Half

A similarity solution has been obtained for a fluid jet bounded on one side by a separation bubble and on the other by an unbounded region containing the same fluid. The inner boundary has been approximated by a porous pseudowall. The resulting mathematical model reduces to other cases such as the plane wall jet and the free curved jet. A two-parameter family of solutions to the resulting nonlinear equation for the outer half of the jet correlates well with experimental data.

Pressure Drop and Heat Transfer in Turbulent Duct Flow: A Two-Parameter Variational Method

1995 ◽  
Vol 117 (2) ◽  
pp. 289-295 ◽  
Author(s):  
N. Ghariban ◽  
A. Haji-Sheikh ◽  
S. M. You
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Pressure Drop ◽  
Variational Method ◽  
Turbulent Flow ◽  
Turbulent Shear ◽  
Duct Flow ◽  
Turbulent Shear Stress ◽  
Fully Developed Turbulent Flow ◽  
Two Parameter

A two-parameter variational method is introduced to calculate pressure drop and heat transfer for turbulent flow in ducts. The variational method leads to a Galerkin-type solution for the momentum and energy equations. The method uses the Prandtl mixing length theory to describe turbulent shear stress. The Van Driest model is compared with experimental data and incorporated in the numerical calculations. The computed velocity profiles, pressure drop, and heat transfer coefficient are compared with the experimental data of various investigators for fully developed turbulent flow in parallel plate ducts and pipes. This analysis leads to development of a Green’s function useful for solving a variety of conjugate heat transfer problems.

scholarly journals Principal Features of Fatigue and Residual Strength of Composite Materials Subjected to Constant Amplitude (CA) Loading

Materials ◽  
2019 ◽  
Vol 12 (16) ◽  
pp. 2586 ◽  
Author(s):  
Alberto D’Amore ◽  
Luigi Grassia
Keyword(s):  
Experimental Data ◽  
Residual Strength ◽  
Stress Ratio ◽  
Cyclic Stress ◽  
Constant Amplitude ◽  
General Validity ◽  
Robust Test ◽  
Sudden Drop ◽  
Stochastic Nature ◽  
Two Parameter

This paper summarizes the principal features of composites’ responses when subjected to constant amplitude (CA) cyclic loadings. The stochastic nature of the responses; the absence of a detectable fatigue limit; the sudden drop of strength; the general validity of the strength-life equal-rank assumption (SLERA); and, ultimately, the residual strength-life equal-rank assumption (RSLERA) are discussed on the basis of the selected experimental data available in literature. The objective is defining a robust test in order to ascertain the reliability of the phenomenological models. A two-parameter phenomenological model accounting for the maximum cyclic stress, σmax, and the stress ratio, R = σmin/σmax, was used for guidance through the phenomenology of fatigue. It is concluded that the robustness of the models dealing with fatigue can be checked only when the characteristics of the composites’ responses are described simultaneously with fixed parameters.

Two-parameter mechanistic model for the fatigue crack growth of metals

2019 ◽  
Vol 12 (2) ◽  
Author(s):  
Tawqeer Zada
Keyword(s):  
Experimental Data ◽  
Fatigue Crack ◽  
Fatigue Crack Growth ◽  
Crack Growth ◽  
Fatigue Failure ◽  
Mechanistic Model ◽  
Model Development ◽  
Two Parameters ◽  
Crack Growth Model ◽  
Two Parameter

In this paper, a two-parameter mechanistic model for the fatigue crack growth has been developed. Fatigue failure is the major causes of mechanical structural failure. The fatigue failure progress in three stages crack initiation, crack growth and final failure. The fatigue crack growth has been modelled by different approaches, however these approaches are generally empirical. In this paper, a mechanistic fatigue crack growth model is proposed. The striation and its relation to the cyclic load is used for the model development. Scanning electronic microscope results are used to establish relation between striation and crack growth. The developed model is two-parameters. The model has been implemented and validated using experimental data from the literature. The model prediction is satisfactory in region II of the crack growth curve. However, in region I and region III the model deviates from experimental data. It is suggested to incorporate interaction of monotonic and cyclic loading in the mechanistic modelling for the fatigue growth.

Crankshaft Fatigue Test and Statistical Distribution of Fatigue Experimental Data

2013 ◽  
Vol 401-403 ◽  
pp. 93-96
Author(s):  
Zhi Ming Wang ◽  
Peng Min Lv
Keyword(s):  
Experimental Data ◽  
Regression Analysis ◽  
Fatigue Strength ◽  
Weibull Distribution ◽  
Strength Test ◽  
Statistical Distributions ◽  
Statistical Regression ◽  
Minimum Value ◽  
Maximum Value ◽  
Two Parameter

This study has finished the crankshaft fatigue strength test by the rational experimental method. And based on the experimental data, the statistical regression analysis of eight commonly used hypothesis distributions, namely Weibull (two-and three-parameter), normal, lognormal, extreme minimum value, extreme maximum value, and exponential (one-and two-parameter), are developed. Then the degree of fitting effect between the experimental data with the eight statistical distributions is evaluated. The result shows that six kinds of statistical distributions, including Weibull (two-and three-parameter), normal, lognormal, extreme minimum value, extreme maximum value, have good fitting effect. In all distributions, the best one is three-parameter Weibull distribution.

Failure Behavior of Closed Cell Foams

2000 ◽  
Author(s):  
Richard M. Christensen ◽  
Steven J. DeTeresa
Keyword(s):  
Experimental Data ◽  
Failure Behavior ◽  
Refined Theory ◽  
Normal Stresses ◽  
Foam Material ◽  
Closed Cell ◽  
Uniaxial Compressive Stress ◽  
Two Parameter ◽  
Parameter Theory ◽  
Cell Foam

Abstract A two-parameter theory of failure is developed for materials for which the uniaxial compressive stress failure magnitude is less than that for uniaxial tension. The theory is compared with data for a closed cell foam material under combined shear and normal stresses. Although the theory shows the correct general behavior, it probably omits certain finer scale features seen in the data. A more refined theory is now being developed, along with further experimental data.

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