Search results for " angles"
showing 10 items of 30 documents
Simplified analytical model for moment–axial force domain in the presence of shear in R.C. members externally strengthened with steel cages
2015
Equations for a hand calculation of moment–axial force domain in the presence of shear for R.C. beam/column externally strengthened with steel angles and strips are developed. The analytical derivation is made assuming, for axial load and flexure, the equivalent stress-block parameters for internal forces, considering the confinement effects induced in the concrete core by external cages both in the cases of strips or angles yielding. Limit states due to bond failure, concrete crushing and yielding of steel angles and strips in flexure and in shear, including moment-to-shear interaction, are considered. The proposed model gives results in a good agreement with available experimental data an…
Uncertainty evaluation in power measurements with commercial data acquisition boards
2011
The paper deals with the metrological characterization of a digital wattmeter developed by using a personal computer, a shunt, two commercial data acquisition boards and commercial software. The uncertainty of the active power measurements is assessed individually characterizing the voltage channel, the current channel and the phase displacement measurement between the two channels. In particular, the uncertainty on the voltage and current rms measurements is evaluated by using an already proposed approach based on the Monte Carlo method and on the usage of five parameters, while the uncertainty on the phase angle is experimentally estimated. In order to validate the proposed approach for t…
The Use of Accelerometers and Gyroscopes to Estimate Hip and Knee Angles on Gait Analysis
2014
In this paper the performance of a sensor system, which has been developed to estimate hip and knee angles and the beginning of the gait phase, have been investigated. The sensor system consists of accelerometers and gyroscopes. A new algorithm was developed in order to avoid the error accumulation due to the gyroscopes drift and vibrations due to the ground contact at the beginning of the stance phase. The proposed algorithm have been tested and compared to some existing algorithms on over-ground walking trials with a commercial device for assisted gait. The results have shown the good accuracy of the angles estimation, also in high angle rate movement.
Forces and flow structures evolution on a car body in a sudden crosswind
2014
A vehicle driver is commonly exposed to strong side air flows, for example when passing through a wind gust. The aerodynamic efforts generated in these situations may induce undesired lateral deviations, which can lead to dramatic effects, if the driver is surprised. In order to simulate a sudden yaw angle change on a moving vehicle, a double wind tunnel facility, adapted from the one of Ryan, Dominy, 2000. Wake Surveys Behind a Passenger Car Subjected to a Transient Cross-wind Gust. SAE Technical Paper No. 2000-01-0874 is developed. Two Windsor car body models, differing from their rear geometry, are analysed. The transient evolution of the side force and yaw moment aerodynamic coefficient…
Expected principal stress directions under multiaxial random loading. Part II: Numerical simulation and experimental assessment through the weight fu…
1999
In Part I of the present work, the theoretical aspects of a proposed procedure to determine the expected principal stress directions under multiaxial random loading have been discussed. This procedure consists of averaging the instantaneous values of the three Euler angles through weight functions. In Part II here, a numerical simulation is presented to illustrate the above theoretical method. As an example, the algorithm proposed is applied to some experimental biaxial in- and out-of-phase stress states to assess the correlation between the expected principal stress directions and the position of the experimental fatigue fracture plane for such tests.
On Detection of Yaw and Roll Angle Information for Vehicle Oblique Crash using Hough Transform
2014
When performing vehicle crash tests, it is common to capture high frame rate video (HFR) to observe the vehicle motion during the impact. Such videos contain a lot of information, especially when it comes to geometric data. The yaw and roll angles from the HFR video is detected by using the Hough Transform and Matlab's Image processing Toolbox. The measured Yaw angle from the HFR video are compared with real life test data captured with a gyroscopic device inside the vehicle during the oblique vehicle impact.
Reduction of parameters in failure criteria for multiaxial Random Fatigue
1990
In the paper some equivalent methods of determining the expected fatigue fracture plane position have been presented. These methods make use of elements of a full linear rotation group. Replacing nine direction cosines, mutually related, by three Euler angles we obtain a reduced number of parameters used for the description of the excepted fatigue fracture plane position. New mathematical forms of the fatigue criteria with a reduced number of independent parameters have been presented well.
Critical Fracture Plane Under Multiaxial Random Loading by Means of Euler Angles Averaging
1999
ABSTRACT Several authors have experimentally observed that the position of the fatigue fracture plane strongly depends on the directions of the principal stresses or strains. The expected principal stress directions under multiaxial random loading are obtained herein by averaging the instantaneous values of the three Euler angles through some suitable weight functions, in order to take into account the main factors influencing the fatigue fracture behaviour. Then the correlation between such theoretical principal directions and the experimental fracture plane is examined for some biaxial random fatigue tests.
No-Reference 3D Mesh Quality Assessment Based on Dihedral Angles Model and Support Vector Regression
2016
International audience; 3D meshes are subject to various visual distortions during their transmission and geometrical processing. Several works have tried to evaluate the visual quality using either full reference or reduced reference approaches. However, these approaches require the presence of the reference mesh which is not available in such practical situations. In this paper, the main contribution lies in the design of a computational method to automatically predict the perceived mesh quality without reference and without knowing beforehand the distortion type. Following the no-reference (NR) quality assessment principle, the proposed method focuses only on the distorted mesh. Specific…
Facultat de Filologia Traducció i Comunicació
2008
La Universitat de València t'obri les seues portes. En les seues Facultats i Escoles Universitàries descobriràs una àmplia oferta d'estudis, equipament docent d'última tecnologia, instal·lacions esportives i culturals i una completa xarxa de biblioteques. Tot el que necessites per a accedir a una formació integral que garantisca el teu futur professional.