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Afișează articolele 61-80 of 2993
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Structural Requirements of Bituminous Paving Mixtures
(Universitatea "Dunărea de Jos" din Galați, 2002)In this work, the autors present some of the principal issues and challenges associated with the design and production of bituminous mixtures that can meet the ever-increasing structural needs of modern pavements. -
The Dynamic Study of the Crane "MT-40" in the Process of Gyrations
(Universitatea "Dunărea de Jos" din Galați, 2002)This work proposes the determination of the dynamic behavior of a tower crane in the process of gyration in sight of a move burdens in the most disadvantageous conditions and namely: in the crane’ s hook it is a solid body ... -
The Analysis of the Dynamic Response of the Hydrostatic Driving Systems in a Closed Circuit
(Universitatea "Dunărea de Jos" din Galați, 2002)The hydrostatic actions in a closed circuit were remarked in the action of the technological equipment both for achievement of translation motions with linear hydrostatic engines with bilateral stem and for rotational ... -
Mathematical Model for Frequency-Dependent soil Propagation Analysis
(Universitatea "Dunărea de Jos" din Galați, 2002)Vibration analyses of advanced technology facilities typically must consider frequency as well as amplitude of vibration. A soil propagation model is proposed which will allow the use of site-specific, measurable, frequency ... -
Phisycal and Mathematical Model Forvibratory Driving Process Analysis
(Universitatea "Dunărea de jos" din Galați, 2002)Vibratory driving of pile is one of the technologies used for powerless basement soil deep consolidation. This process consist by favouring the pile penetration in soil, whereupon when vibrations using. Experimentally, was ... -
Installation for Centrifugal Casting of Bimetallic Jacks
(Universitatea "Dunărea de Jos" din Galați, 2002)This issue presents an bronze casting technology of steel jack by centrifuging as well as it’s installation. We try to realize a machine by date theme for mechanization of technological operation. The constructive solution ... -
Robot Type Manipulator for Serving of a Bolts Hardening System Outline
(Universitatea "Dunărea de Jos" din Galați, 2002)The paper work refers to a flexible manufacturing cell where the bolts hardening system within a relatively wide range of dimensions is completely automatic. For this purpose, a robot type manipulator serving an induction ... -
Considerations Upon Breaking Strength of Nodular Cast Iron Under Plastic Deformation
(Universitatea "Dunărea de Jos" din Galați, 2002)The work aims to demonstrate the existence of a mathematics connection between breaking strength and degree of plastic deformation in case of nodular cast iron. Research made along time starting 1932-1934 until now, ... -
The calculation of Pressure Forces Resultant About Rotor Bearings of Volumetrical Pumps and Motors with Radial Palettes
(Universitatea "Dunărea de Jos" din Galați, 2002)The objective of this paper refers to the presentation the calculation of pressure forces resultant about the palettes and the lateral rotor surface of volumic pumps and motors with radial palettes. This calculation is ... -
Response Behaves of Earthmoving Vehicle Where the Slip Ratio are Variation Linear
(Universitatea "Dunărea de Jos" din Galați, 2002)In this paper, the autor conceptualize the loader equations of motion for dynamic analysis of traction system where the slip ratio are variation linear. The wheel loader simulation model was formulated in terms of ... -
The Behavior of Mechanical Model Wheel' S Loader
(Universitatea "Dunărea de Jos" din Galați, 2002)In this work is described a dynamical model for the tire-suspension system of wheel loader. This model is based on the subdivision of the global dynamical system into its physical components: the tire, the wheel, ... -
Influence of High Performance Voltage Converters Supply Upon the Induction Motors Behaviour
("Dunarea de Jos" University of Galati, 2002)The induction motors supply by converters leads to a distorted regime accompanied by some parasite torques and some supplementary losses. These aspects are emphasized further on because their quantitative determinations ... -
Energetic Optimal Control of Adjustable Drive Systems
("Dunareade Jos" University of Galati, 2002)In the paper is developed a new control strategy for the adjustable speed drives. The strategy consists in the energetic optimal control of the dynamic regimes as starting, stopping and reversing. The main developed ... -
Simple Approach for Induction Motor Control Using Reconfigurable Hardware
("Dunarea de Jos" University of Galati, 2002)The paper deals with rotor-field-oriented vector control structures for the induction motor drives fed by the so-called tandem frequency converter. It is composed of two different types of DC-link converters connected ... -
On the Snubber Influence to the Switching and Conduction Losses in a Converter Using Switched Capacitor
("Dunarea de Jos" University of Galati, 2002)The paper deals to design and to compute the snubber parameters influence on the switching and conduction losses of the transistors (IGBT) used as bidirectional switches in a converter with switched capacitor. The converter ... -
Speed and Rotor Flux Estimation in Speed Sensorless Control of Induction Motor
("Dunarea de Jos" University of Galati, 2002)The paper compares the performances of several adaptive rotor flux and speed estimation methods used in speed sensorless vector control of induction motor. First, a short review of Luenberger, Gopinath, MRAS, Torque Error ... -
New Power Optimization Posssibilities
("Dunarea de Jos" University of Galati, 2002)In this paper there are given a few mathematical relations for the power analysis in un-sinusoidal regime. If the voltage is sinusoidal and the current is unsinusoidal, the apparent power will be ascertained by the active ... -
Energetic Macroscopic Representation Applied to an Electrical Urban Transport System
("Dunarea de Jos" University of Galati, 2002)An energetic description of the electric transport urban system ASTRAIK 415T is proposed according to a specific formalism. This is used to simulate the trolleybus system, equipped with a chopper and a direct current ... -
Some Considerations Regarding the Efficiency of the Electromechanical Motion
("Dunarea de Jos" University of Galati, 2002)Control techniques for servo drive which run at variable speed for prolonged time is developed on the base of minimum energy dissipation in a feed-forward structure. The optimal control laws are determinate using the ... -
Comparison on Sensorless Control of Synchronous Motors
(Dunareade Jos University of Galati, 2002)The paper compares two different methods for speed and position estimation in AC permanent magnet synchronous motors vector control applications. The first method implies two observer blocks — one for the speed, and the ...
