input frequency is one of the important variables in design and performance analysis of single-sided linear induction motors (slims). changing the frequency changes both the dimension of the slim in design process and the performance of the designed motor. the frequency influences the induced eddy currents in the secondary sheet as well as saturation level of the secondary back-iron. in this pa...

We approached our first participation in TREC with an interest in performing retrieval on the output of automatic speech-to-text (speech recognition) systems and a background in performing topic-labeling on such output. Our primary thrust, therefore, was to participate in the SDR track. In conformance with the rules, we also participated in the Ad Hoc text-retrieval task, to create a baseline f...

This article presents the theory and operation of a null-type, inverted pendulum thrust stand. The thrust stand design supports thrusters having a total mass up to 250 kg and measures thrust over a range of 1 mN to 5 N. The design uses a conventional inverted pendulum to increase sensitivity, coupled with a null-type feature to eliminate thrust alignment error due to deflection of thrust. The t...

A high-thrust screw-type piezoelectric ultrasonic motor with a three-wavelength exciting mode is proposed in this paper. The motor mainly includes a stator and a screw output shaft, and the stator is composed of twelve rectangular piezoelectric plates and a hollow metal elastomer with an internal thread. The stator can be excited to generate the combined micro ultrasonic vibration mode. With th...

We are developing a visually-guided autonomous underwater vehicle. We have implemented a computed torque controller, using Euler parameters, for position and velocity control. This formulation eliminates singularity in the model and controller and offers some degrees of coupling between vehicle degrees of freedom. A calibrated thruster model which computes thrust output from measured voltage an...

A brute-force testing technique was applied on a robotic controlled-curvature flapping fin propulsor to investigate output thrust and power consumption trends with respect to flapping frequency, amplitude, and gait. It has been discovered that maximum thrust and maximum propulsive efficiency can coexist, that flapping frequency and amplitude are sometimes interdependent parameters, and that act...

Zusammenfassung Der Beitrag beschreibt eine exakte E/ALinearisierung für die translatorische Dynamik eines Quadrocopters. Die hierfür relevante Lageinformation reduziert sich auf die Ausrichtung des Schubvektors (bzw. der körperfesten zAchse), welche mit zwei Freiheitsgraden beschrieben werden kann. Hierzu wird im vorliegenden Beitrag ein spezielles Schubachsenquaternion eingeführt. Die E/A-Lin...

The main affecting parameter for Delamination of the composites and in turn the failure of composites is the Thrust force. In the present work an attempt has been made in order to investigate the Thrust force generated during drilling of the TiO2 and ZnS filled Glass Fabric Reinforced Polymer Matrix Composites (GFRP). The volume fractions in the matrix were chosen as 1, 2 and3%. A plan of exper...

The secondary back-iron plays important role in performance of single-sided linear induction motors (SLIMs). On one hand, it provides a return path for the primary flux; on the other hand, it is employed as a mechanical support for the secondary sheet. The conductivity of the iron used in the back-iron as well as its magnetic permeability influence the outputs of the machine, while the magnetic...

Wind turbines frequently operate under situations of pronounced flow inclinations, such as in complex terrain. In the present work the performance and rotor thrust of downwind and upwind turbines in upward and downward flow inclinations are experimentally investigated. In an upward flow inclination of +13°, downwind turbines are shown to have a 29% larger power output than a corresponding upwin...