Search Results

You are looking at 1 - 10 of 15 items for :

  • "explicitness" x
  • Materials and Applied Sciences x
  • Architecture and Architectonics x
  • Refine by Access: All Content x
Clear All

Detection of cracks in mechanical components as early as possible enables monitoring structural health and scheduling efficiently the maintenance tasks such as replacing the critical parts just in time. Vibration analysis based techniques for crack detection have been largely considered in the framework of beam-like structures. This methodology relies essentially on the observed changes of beam frequencies and mode shapes induced by the presence of damage. In the present work, using an explicit analytical model assessing the effect of a crack on beam strain energy, the beam first resonance frequencies as they depend on a single crack defect characteristics were evaluated. The crack equations were obtained by means of fracture mechanics approach. Variations of the first beam frequencies and modes shapes were then related explicitly to the location and depth of the crack. Measuring the beam frequency changes and monitoring their variations can be used to perform identification of the crack defect parameters by solution of an inverse problem.

Restricted access

Abstract

In this paper a 3D finite element model of the bending process for circular aluminium alloy tube has been built using the explicit code eta/Dynaform and validated by comparing the experiments. The experiments were carried out by using a hand bender with the same bending principle as a rotary draw numerical controlled (NC) bender. The relationship between quality parameters of bent tubes, in terms of cross-section distortion and wall thinning, and the angular position along the bent tube is discussed experimentally in combination with FE simulation. Then, the effects of bending radius (R) are investigated using simulation of the bending process based on the finite element model. The results show that with the increase of bending radius, the cross-section degradation factor (Ψ) and wall thinning degree (ξ) decreases rapidly.

Restricted access

disciplines. In the computational perspective, as defined by [ 19 ], an ontology is “a formal explicit specification of a shared conceptualization for a domain of interest.” It is an engineering artifact that represents a specific domain of knowledge [ 20, 21

Open access

explicitly defined in the code written, in fact, in MATLAB DSP block, a rectangular window is equivalent to no window at all. 3 Verification In order to verify that the original designs function correctly, the function of a few key modules has to be verified

Open access

that occurs following the emission of ultrasonic waves by PAs transducers. This consists of a simple analytic expression that gives explicitly the displacement field caused by the ultrasonic wave propagation in the tested medium. Predictions of this

Open access

-refundable tenders or establishes a venture capital fund with the explicit purpose of supporting the industry 4.0 [ 17 ]. The survey made in the sphere of the international companies about preparedness for the new digital industrial revolution shows a slightly more

Open access

characteristic equation, the K c is determined as below: (25) K c = ω n 3 b 2 x − ω n 3 K b b 1 5 The proposed hybrid modified RBF neuro-deadbeat controller design Instead of explicitly choosing a value for the series gain K of the designed deadbeat

Open access

explicit performance indicators as ‘good’ or ‘poor’, Asif et al. [ 5 ] showed that this may provide timely warning and support for low-scoring students, and recommendations and opportunities for high-performing students. Yaacob et al. [ 6 ] suggested

Open access

from the Direct Numerical Simulation (DNS) of explicit full time-dependent flow field. The main motivation of this approach is related to the fact that, in most CFD applications, knowing how turbulence affects the mean flow is enough and no real need

Open access

VEDs, E is the Young's modulus, and I the moment of inertia of beam section. Finally, the second half term in Eq. (4) constitutes the vector of moving modal forces. It has the explicit following form [ 16 ] (5f) F ( t ) = ∑ k = 1 N v F k [ H ( t

Open access