Linear flux switching motors with simple passive segmented secondary, referred as Segmented Secondary Linear Flux Switching Motors (SSLFSMs), have low cost secondary and therefore are applicable to transportation systems like Maglev. However, it is shown that the SSLFSMs suffer from high thrust ripples. In this paper, minimizing SSLFSM thrust ripples besides maximizing its developed thrust are ...

The Electromagnetic Aircraft Launch System (EMALS) offers significant benefits to the aircraft, ship, personnel, and operational capabilities. EMALS has such advantages as high thrust, good controllability, reusable, etc., as a launching motor, a double-side plate Permanent Magnet Linear Synchronous Motor (PMLSM) can provide high instantaneous thrust. This paper presents the design and analysis...

High thrust-to-power ratio on Hall-effect thrusters allows for more efficient thrust generation and better overall performance. It allows Hall-effect thrusters to perform more thrust-intensive maneuvers such as orbit raising, thus saving the mass of a second engine purely for those maneuvers. This paper presents the initial performance measurements of aHall-effect thruster using in-channel elec...

The time-averaged thrust of an incompressible fully pulsed jet containing a period of no flow between pulses is studied experimentally as a function of pulsing duty cycle SrL and the ratio of the ejected slug length (per pulse) to the jet diameter L/D. The parameter ranges investigated were 2 <– L/D <– 6 and 0.1 <– SrL <– 0.98. Significant thrust augmentation by pulsing was observed over the en...

Decreasing the pulse duration helps confine damage, shorten treatment time, and minimize pain during retinal photocoagulation. However, the safe therapeutic window (TW), the ratio of threshold powers for thermomechanical rupture of Bruch's membrane and mild coagulation, also decreases with shorter exposures. Two potential approaches toward increasing TW are investigated: (a) decreasing the cent...

This study aims to determine change in optimal locations of dual trailing-edge flaps for various thrust coefficient to solidity (Ct /σ) ratios of helicopter to achieve minimum hub vibration levels, with low penalty in terms of required trailing-edge flap control power. Polynomial response functions are used to approximate hub vibration and flap power objective functions. Single objective and mu...

The T-220HT Hall-effect thruster is modified to include in-channel electrodes and additional magnetic coils to study ion focusing. The goal of this work is to decrease energy losses from ion-wall neutralization and plume divergence to increase the thrust-to-power ratio. In this paper, thrust and plume measurements on xenon are presented. The thruster was tested from 125 to 300 V at 9 A discharg...

One of the fundamental hurdles in realizing new spectrum sharing allocation policies is that of reliable spectrum sensing. In this thesis, three research thrusts are presented in order to further research in this critical area. The first of these research thrusts is the development of a novel asynchronous and noncoherent modulation classifier for PSK/QAM modulated signals in flat-fading channel...

In the present study we have developed the agar-fill method for the measurement of gastrointestinal-tract capacity (GTC) to replace the in vitro water-fill method. This would estimate GTC without using complex equipment and techniques, and can be applied to the measurement of GTC for small laboratory animals. We attempted to confirm the efficiency of the agar-fill method by investigating the re...

We study electromagnetically induced transparency for a probe traveling-wave ~TW! laser field in closed Doppler-broadened three-level systems driven by a standing-wave ~SW! laser field of moderate intensity ~its Rabi frequencies are smaller than the Doppler width of the driven transition!. We show that probe windows of transparency occur for values of the probe to drive field frequency ratio R ...