Search results for " MOTOR"

A cerebral nitrergic pathway modulates endotoxin-induced changes in gastric motility

2001

1 This study analyses the neural pathway involved in the modulation of gastric motor function by stress. 2 Systemic administration of low doses of endotoxin (40 m gk g 71 , i.v.) prevents the increase in gastric tone induced by 2-deoxy-D-glucose (200 mg kg 71 , i.v., 2-DG) in urethane-anaesthetized rats. 3 Functional inhibition of aAerent neurones by systemic administration of capsaicin (20+30+50 mg kg 71 , i.m.) in adult rats prevented the inhibitory eAects of endotoxin. 4 Pre-treatment with the nitric oxide synthase (NOS) inhibitor, N G -nitro-L-arginine methyl ester (LNAME), both i.v. (10 mg kg 71 ) and i.c. (200 mg rat 71 ), prevented the inhibitory eAects of endotoxin on gastric tone i…

Relationship Between Heart Rate Recovery After Exercise and Maximal Oxygen Uptake in Sedentary Patients with Type 2 Diabetes

2014

AIMS: Heart rate recovery after exercise (HRR) is an estimate of autonomic modulation of the heart, and has been shown to be inversely associated with type 2 diabetes. Type 2 diabetes is associated with decreased maximal oxygen consumption (VO2max). Aim of our study was to assess the relationship between HRR and VO2max in sedentary patients with type 2 diabetes. METHODS: Maximal exercise testing to determine VO2max (ml ∙ Kg-1 ∙ min-1) was performed in 16 sedentary patients with type 2 diabetes (DP) and in 16 age-matched sedentary healthy controls (HS). HRR (bpm) 2 min after cessation of the exercise was recorded. Simple linear regression was used to assess the relations between HRR and VO2m…

Spin-up instability of electromagnetically levitated spherical bodies

2000

Stability of a solid sphere in both uniform and linear alternating magnetic fields is considered with respect to virtual rotations. When the frequency of the alternating magnetic field exceeds a certain critical threshold depending on the configuration of the field, the sphere is found to spin up around a horizontal axis. The physical mechanism of this instability is the same as that of operation of a single-phase induction motor. Sufficiently small rotational disturbances can be completely suppressed by imposing an axial steady magnetic field of strength comparable to that of the alternating field. Nonlinear stability analysis shows that for sufficiently high frequencies, spin-up can be ca…

Bidirectional random motion driven by globally coupled noisy active elements in an electric field

2004

The assembly of the insulating Brownian particles globally coupled due to the macroscopic flow of the liquid with low conductivity has transitions between the states of random motion and random bidirectional and unidirectional motion. The threshold values of the parameters for the transition to random bidirectional motion is found by the effective field method and correspond to those found by Brownian dynamics. The behavior of the assembly is similar to the behavior of different active multistable systems.

A Lagrangian Approach to the Electromechanical Aspects of the Superconducting Magnets for Maglev

1994

The superconducting magnets for Maglev are exposed during their operation to strong time dependent fields, which can cause losses and therefore can affect the stability of the magnets. In this work the electromechanical behaviour of a superconducting magnet, which is used as field magnet of a linear synchronous motor, is examined.

Field analysis of the magnetic systems for tubular linear reluctance motors

2005

We report a study of tubular linear reluctance motors (TLRMs) in various types of magnetic circuits. We carried out magnetic field analyses and calculated integral parameters of the field. We also determined static characteristics and electromagnetic parameters of the motor. We found good agreement between our calculations and tests of the motor with sinusoidal excitation.

Rotor “Nonsynchronous” Control Of Induction Motors. Part I: Determination Of A Mathematical Model

1983

Control of the speed of a DC motor by employeeing pulse width modulation (PWM) technique

2009

This paper is mainly focused on the technique of pulse width modulation for controlling the speed of a 12 volt DC motor more efficiently. A potentiometer was used to generate a wide variety of pulses. The output of the controlling circuit (Pulse Width) was connected to the second circuit as input for direction control. Here a single push switch was used to change the state (stopforward-stop-reverse) of the DC motor. These two circuits were combined into one for ease of use. Third circuit was designed to measure the speed of the motor by employing an opto-electronic sensor, an amplifier and a two blade fan to interrupt the signal transmission of the sensor. Finally, the output of the sensor …

Analysis of Torque Developed in Axial Flux, Single-Phase Brushless DC Motor With Salient-Pole Stator

2004

An analysis of the torque developed by a single-phase disc brushless permanent magnet motor with salient-pole stator is presented. The machine represents a new family of brushless disc motors with the starting torque issue appearing to be most challenging. To produce a starting torque, the permanent magnets on one of the rotor discs are distributed nonuniformly. However, this significantly distorts a shape of the cogging torque versus rotational angle characteristic which, in turn, affects a waveform of the overall torque. A three-dimensional (3-D) finite-element model is used for the purpose of determining of angular variations of the torque developed by the motor. To find how the torque v…

Active Brownian Motion Models and Applications to Ratchets

2008

We give an overview over recent studies on the model of Active Brownian Motion (ABM) coupled to reservoirs providing free energy which may be converted into kinetic energy of motion. First, we present an introduction to a general concept of active Brownian particles which are capable to take up energy from the source and transform part of it in order to perform various activities. In the second part of our presentation we consider applications of ABM to ratchet systems with different forms of differentiable potentials. Both analytical and numerical evaluations are discussed for three cases of sinusoidal, staircase-like and Mateos ratchet potentials, also with the additional loads modeled by…