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Rock fractures are a key contributor to a broad array of Earth surface processes due to their direct control on rock strength as well as rock porosity and permeability. However, to date, there has been no standardization for the quantification of rock fractures in surface process research. In this work, the case is made for standardization within fracture-focused research, and prior work is reviewed to identify various key datasets and methodologies. Then, a suite of standardized methods is presented as a starting "baseline" for fracture-based research in surface process studies. These methods have been shown in pre-existing work from structural geology, geotechnical engineering, and surface process disciplines to comprise best practices for the characterization of fractures in clasts and outcrops. This practical, accessible, and detailed guide can be readily employed across all fracture-focused weathering and geomorphology applications. The wide adoption of a baseline of data collected using the same methods will enable comparison and compilation of datasets among studies globally and will ultimately lead to a better understanding of the links and feedbacks between rock fracture and landscape evolution. [ABSTRACT FROM AUTHOR]

The subject of this article is the gain scheduled fuzzy control for the field of distributed parabolic solar collectors. System modeling has been done in different operation points. These different operation points are caused by various conditions occured by the nonlinear and time-varying behavior of the system based on the different operating points that are considered due to the presence of various disturbances and inputs, the switching mechanism between controllers is performed by a time-controlled structure, which will reduce the effects of disturbances on the system response. The PID controller is then designed based on the Anti-Windup circuit and a feedforward controller that runs parallel to it. The use of a feedforward controller can also improve the system response time and its overshoot value, as well as reduce the effect of disturbances on the system. [ABSTRACT FROM AUTHOR]

In the present study, in order to detect the fault of the gearmeshs, two engaged gears based on research department of a major automotive company have been modeled. First off, by using the CATIA software the fault was induced to the output gear. Then, the faulty gearmesh and non-faulty gearmesh is modeled to find the fault pattern to predict and estimate the failure of the gearmesh. The induced defect is according to the frequently practical fault that takes place to the teeth of gears. In order to record the acceleration signals to calculate the decomposition algorithm, mount the accelerometer on accessible place of the output shaft to recognize the pattern. Then, for more realistic simulation, noise is added to the output signal. At the first step by means of Butterworth low pass digital, the noise has to be removed from signals after that by using the Empirical Mode Decomposition (EMD), signals have decomposed into the Instinct Mode Function (IMF) and every IMF were tested by using the Instantaneous Frequency (IF) in way of Hillbert Transform (HT). For this purpose a code was developed in MATLAB software. Then, in order to detect the presence of the fault the frequency spectrum of IMF's are created and defect is detected in gearmesh frequency of the spectrum. [ABSTRACT FROM AUTHOR]

In the present study, the behavior of vibratory cylindrical shells composed of functionally graded material (FGM) containing copper and tungsten under internal pressure and axial compression loads is investigated. An exact solution of free harmonic wave propagation using the theory of three dimensional elasticity is extracted. Then, the dispersion equation is analyzed in conjunction with a Frobenius power series method and natural frequency (eigenvalue) of the shell is obtained using Rayleigh-Ritz method. Furthermore, the present analysis is validated by comparing results with those available in the literature. [ABSTRACT FROM AUTHOR]