Search results for "Earing"
showing 10 items of 867 documents
Study on Improving the Functional Performance of Linear Motion Systems
2015
In the construction of high performance mechanical transmission with high precision in movement and positioning are used ball screws with preloaded double nuts. Among the factors that influence the performance of these transmissions are friction idle torque and friction load torque. Because, theoretically, the friction idle torque is influenced only by the preload force that loading, the double nut of the ball screw, was experimentally determined dependence of that torque of screw speed. Given the set was determined and exposed in the present work, the relation of dependency, idle friction torque, preload force and screw speed. From the relationship thus obtained can determine the instantan…
Flexural behaviour of glass panels under dead load and uniform lateral pressure
2013
Abstract In the present paper the experimental results relative to flexural tests on out-of-plane loaded large scale panels made of laminated structural glass are presented and discussed. Glass panels are parts of the structural facade of the Fontanarossa International Airport of Catania (Italy). Panels are mounted on a rigid testing frame and loaded with an uniformly distributed lateral pressure. Two different kinds of tests were carried-out, cyclic and monotonic, able to reproduce the serviceability and the ultimate conditions of the glass panels when subjected to the coupled effects of dead load and horizontal forces, the latter reproducing the wind action. Results obtained focused the h…
Applicability of over-coring technique to loaded RC columns
2014
Stress determination is a very important step in the assessment of the safety of existing reinforced concrete structures. In rock mechanic this goal is achieved with the over-coring technique. The main idea behind such a technique is to isolate a material sample from the stress field in the surrounding mass and monitor its re-equilibrium deformation response. If the materials remains elastic, and elastic properties are known, stresses may be obtained from the corresponding measured strains. The goal of this paper is to evaluate if the over-coring technique is applicable to reinforced concrete members. The results of an experimental investigation on the behaviour of compressed concrete colum…
Optimal Blankholder Force Path in Sheet Metal Forming Processes: An Al Based Procedure
1999
Abstract Blankholder force plays a fundamental role in the deep drawing process mechanics since it controls, by friction, the material flow into the die cavity. The availability of computer controlled hydraulic presses in the industries promoted a new research field focused on the definition of optimal BHF histories, function of the punch displacement; such studies were aimed to the determination of the so called “process window”, i.e. the BHF path which permits to obtain the maximum height sound component avoiding both wrinkling and tearing. In the paper a design procedure is proposed in order to determine the optimal BHF path in an axisymmetric deep drawing process: in particular, a close…
A New Quasi-Static Cylindrical Roller Bearing Model to Accurately Consider Non-Hertzian Contact Pressure in Time Domain Simulations
2012
The accuracy of the fatigue life calculations in rolling bearing simulations is highly dependent on the precision of the roller-raceway contact simulations. Several different methods exist to simulate these pressure distributions and in time domain bearing simulations, where many contacts need evaluation, the simple and time efficient methods are more popular, yielding erroneous life estimates. This paper presents a new six degree of freedom frictionless quasi-static time domain cylindrical roller bearing model that uses high precision elastic half-space theory to simulate the contact pressures. The potentially higher computational demand using the advanced contact calculations is addressed…
Generalization of Shear Truss Model to the Case of SFRC Beams with Stirrups
2012
A theoretical model for shear strength evaluation of fibrous concrete beams reinforced with stirrups is proposed. The formulation is founded on the theory of plasticity and the stress field concepts, generalizing a known plastic model for calculating the bearing capacity of reinforced concrete beams, to the case of fibrous concrete. The beneficial effect of steel fibres is estimated taking into account the residual tensile strength of fibrous concrete, by modifying an analytical constitutive law which presents a plastic plateau as a post-peak branch. Around fifty results of experimental tests carried out on steel fibrous concrete beams available in the literature were collected, and a compa…
Understanding Deafhood: in search of its meanings.
2013
The authors argue that Deafhood (a term coined by Dr. Paddy Ladd) is an open-ended concept with an essentialist core. They describe how deaf people who have attended their Deafhood lectures and workshops have perceived different aspects of the Deafhood concept, and compare the basic tenets of Deafhood and criticisms on Deafhood to theories and criticisms on feminist essentialisms. The authors find that the vagueness and wideness of the Deafhood concept is one of its strengths, though they also find that it is in some respects problematic to combine and unite ontology and liberation theory in one concept. They further suggest that the ontological aspects of Deafhood need to be foregrounded. …
METALANG. Protocolo franco-español de exploración de habilidades metalingüísticas en niños de 6 a 9 años: un estudio preliminar
2012
International audience; In this work are described the principles of functional-pragmatic and the reasons for developing an exploration protocol for natural metalinguistic abilities. This study explains the base hypothesis and structure of METALANG protocol. This protocol consists in a Test and a Questionnaire for parents with two different scales: A = Ability, B = Frequency. Each element of the protocol has 6 sections and 40 items. It is performed a preliminary contrast with 12 subjects aged 6 to 9 years. Among the 12 subjects, 4 were diagnosed with dysphasia. METALANG shows high scores in reliability and internal consistency. This result confirms the hypothesis that it is possible a joint…
The Role of Parenting Styles in Children's Problem Behavior
2005
This study investigated the combination of mothers' and fathers' parenting styles (affection, behavioral control, and psychological control) that would be most influential in predicting their children's internal and external problem behaviors. A total of 196 children (aged 5-6 years) were followed up six times from kindergarten to the second grade to measure their problem behaviors. Mothers and fathers filled in a questionnaire measuring their parenting styles once every year. The results showed that a high level of psychological control exercised by mothers combined with high affection predicted increases in the levels of both internal and external problem behaviors among children. Behavio…
Application of the discussion groups and initial phases of the qfd methodology to the study of Valencian ball trinquetes
2011
Montaner AM, Montaner C, Perez-Soriano P, Carrasco-Embuena V, Llana-Belloch S. Application of the discussion groups and initial phases of the qfd methodology to the study of valencian ball trinquetes. J. Hum. Sport Exerc. Vol. 6, No. 4, pp. 629-638, 2011. The purpose of this research is to show an opinion study about the specifications that the valencian ball trinquetes should have according to the players’ opinion. The valencian ball game is a native sport with a great cultural tradition in the Valencian Community and it has been practised in the trinquetes since the XIV century. Despite its history, these facilities do not have the normative requirements for suitable sport development. Th…