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On being a mentor
This article explores issues relating to mentoring students, particularly ophthalmic nursing students. It highlights the importance of mentorship in learning in practice, which in turn is critical to students' education in a competency-based profession. It considers the factors essential in successful mentoring, including two-way feedback, and the importance of mentors understanding the nature of the psychological processes involved and how to assess students' learning and competencies. It also highlights the crucial gate-keeping role of mentors in ensuring that students are fit to practise, and the importance of nurse mentors themselves being fit to practise
Magnetic Phases of Large-Spin Ultracold Bosons: Quantum Dimer Models and Spin Liquid Phases
This thesis investigates the plausibility of producing a quantum spin liquid (QSL) with ultracold bosonic atoms optically confined to the Mott insulating state. QSLs have received a great deal of attention for being an antiferromagnetic groundstate with many exotic properties, including the absence of local order, long-range entanglement, and fractionalized excitations. However, the identification and characterization of these phases in solid state systems remains a great challenge. Here we outline an alternate route to uncovering the QSL phase, which from the nature of spin angular momentum for ultracold atoms encounters many properties unique to these systems along the way. This proposal is possible because the magnetic exchange interactions for Mott insulating ultracold atoms are mediated by the hopping of whole atoms. Whole-atom exchange—a unique property of cold atoms—allows large fluctuations between the quantized Zeeman sublevels of each atomic spin. As we demonstrate, these fluctuations increase when large-spin atoms are used, or when interactions are tuned via optical Feshbach resonance (OFR). These strong quantum spin fluctuations inhibit classical magnetic ordering, and lead to a QSL ground state.
To illustrate the relationship between the spin magnitude, interaction strength, and QSL ground state, we present two distinct approaches to solving the relevant Hamiltonian. With mean field theory we find that for large spin (f \u3e 2), and strong scattering through the spin-singlet channel, that magnetically-ordered Bose-Einstein condensates are unstable to the formation of a QSL. We then utilize Rayleigh-Schodinger perturbation theory to derive an effective Hamiltonian for our system in the Hilbert space of nearest-neighbor singlet coverings. At large spin this Hamiltonian produces a type of quantum dimer model (QDM), which are known to possess QSL phases. We derive the QDM parameters t, t′ and V as a function of spin on several lattices, finding they scale with the inverse number of Zeeman sublevels. We then determine the proximity of the physically accessible states to the QSL phase, and discuss how other regions of the phase diagram may be accessed. We then conclude by highlighting several advantages to studying QSLs and QDMs with ultracold bosons
Growing pains with information overload
Emotional and cognitive overload with information technology can be caused by more than just too many digital devices. © 2006 IEEE
Magnetic control assembly qualification model
Fabrication and testing of the magnetic control assembly (MCA) are summarized. The MCA was designed as an add-on unit for certain existing components of the Nimbus and ERTS attitude control system. The MCA system consists of three orthogonal electromagnets; a magnetometer probe capable of sensing external fields in the X, Y, and Z axes; and the control electronics. An operational description of the system is given along with all major drawings and photographs. Manufacturing and inspection procedures are outlined and a chronological list of events is included with the fabrication summary
Sensitive and broadband measurement of dispersion in a cavity using a Fourier transform spectrometer with kHz resolution
Optical cavities provide high sensitivity to dispersion since their resonance
frequencies depend on the index of refraction. We present a direct, broadband,
and accurate measurement of the modes of a high finesse cavity using an optical
frequency comb and a mechanical Fourier transform spectrometer with a kHz-level
resolution. We characterize 16000 cavity modes spanning 16 THz of bandwidth in
terms of center frequency, linewidth, and amplitude. We retrieve the group
delay dispersion of the cavity mirror coatings and pure N with 0.1
fs precision and 1 fs accuracy, as well as the refractivity of the
3{\nu}1+{\nu}3 absorption band of CO with 5 x 10 precision.
This opens up for broadband refractive index metrology and calibration-free
spectroscopy of entire molecular bands
Paper Session II-C - Pegasus and Taurus Launch Vehicles
The Pegasus Air-Launched Space Booster is an innovative new space launch vehicle now in full scale development and initial production. Pegasus, developed by a privately-funded joint venture of Orbital Sciences Corporation (OSC) and Hercules Aerospace Company, is a three-stage, solid-propellant, inertially-guided, winged vehicle that is launched from a carrier aircraft at 40,000 ft and Mach .8. This 50 ft long, 41,000 Ib vehicle can deliver a payload of 900 Ib into a low inclination, 150 nmi Earth orbit. The first two Pegasus flights are sponsored by the Defense Advanced Research Projects Agency (DARPA), with additional missions currently reserved by the U.S. Air Force and commercial customers.
Pegasus was conceived to provide a more flexible and more efficient launch system for small space payloads by taking advantage of the many benefits inherent in the airborne launch approach. The Pegasus system achieves a substantial improvement in payload performance relative to comparable ground-based launch vehicle designs, while also providing numerous advantages in operational flexibility and cost effectiveness.
The flight vehicle, shown in Figure 1, consists of three solid-propellant rocket motors, a fixed highmounted composite delta wing, an aft skirt assembly including three composite fins, an avionics section atop the third stage, and a two-piece composite payload fairing
Improvements for Vision-based Navigation of Small, Fixed-wing Unmanned Aerial Vehicles
Investigating alternative navigation approaches for use when GPS signals are unavailable is an active area of research across the globe. In this paper we focus on the navigation of small, fixed-wing unmanned aerial vehicles (UAVs) that employ vision-based approaches combined with other measurements as a replacement for GPS. We demonstrate with flight test data that vehicle attitude information, derived from cheap, MEMS-based IMUs is sufficient to improve two different types of vision processing algorithms. Secondly, we show analytically and with flight test data that range measurements to one other vehicle with global pose is sufficient to constrain the global drift of a visual inertial odometry-based navigation solution. Further, we demonstrate that such ranging information is not needed at a fast rate; that bounding can occur using data as infrequent as 0.01Hz
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