The Aesthetic Uncanny: Staging Dorian Gray

This article discusses my theatrical adaptation of Oscar Wilde's The Picture of Dorian Gray (1891) for the Edinburgh Festival Fringe (2008). Freud's concept of the uncanny (1919) was treated as a purely aesthetic phenomenon and related to late nineteenth century social and literary preoccupations such as Christianity, the supernatural and glamorous, criminal homosexuality. These considerations led to a conceptual ground plan that allowed for experiments during rehearsal in a form of theatrical shorthand

New considerations on scale extrapolation of wing pressure distributions affected by transonic shock-induced separations

Use of this analytical parameter, it is shown, highlights the distinction between cases which are dominated by trailing-edge separation, and those for which separation at the shock foot is dominant. Use of the analytical parameter and the distinction noted above greatly improves the correlation of separation data and the extrapolation of wind tunnel data to flight conditions

Toward a better understanding of the doping mechanism involved in Mo(tfd-COCF3)3_3)_3 doped PBDTTT-c

In this study, we aim to improve our understanding of the doping mechanism involved in the polymer PBDTTT-c doped with(Mo(tfd-COCF3)3. We follow the evolution of the hole density with dopant concentration to highlight the limits of organic semiconductor doping. To enable the use of doping to enhance the performance of organic electronic devices, doping efficiency must be understood and improved. We report here a study using complementary optical and electrical characterization techniques, which sheds some light on the origin of this limited doping efficiency at high dopant concentration. Two doping mechanisms are considered, the direct charge transfer (DCT) and the charge transfer complex (CTC). We discuss the validity of the model involved as well as its impact on the doping efficiency.Comment: Accepted manuscript, J. Appl. Phy

A DMRG Study of Low-Energy Excitations and Low-Temperature Properties of Alternating Spin Systems

We use the density matrix renormalization group (DMRG) method to study the ground and low-lying excited states of three kinds of uniform and dimerized alternating spin chains. The DMRG procedure is also employed to obtain low-temperature thermodynamic properties of these systems. We consider a 2N site system with spins $s_1$ and $s_2$ alternating from site to site and interacting via a Heisenberg antiferromagnetic exchange. The three systems studied correspond to $(s_1 ,s_2 )$ being equal to $(1,1/2),(3/2,1/2)$ and $(3/2,1)$; all of them have very similar properties. The ground state is found to be ferrimagnetic with total spin $s_G =N(s_1 - s_2)$. We find that there is a gapless excitation to a state with spin $s_G -1$, and a gapped excitation to a state with spin $s_G +1$. Surprisingly, the correlation length in the ground state is found to be very small for this gapless system. The DMRG analysis shows that the chain is susceptible to a conditional spin-Peierls instability. Furthermore, our studies of the magnetization, magnetic susceptibility $\chi$ and specific heat show strong magnetic-field dependences. The product $\chi T$ shows a minimum as a function of temperature T at low magnetic fields; the minimum vanishes at high magnetic fields. This low-field behavior is in agreement with earlier experimental observations. The specific heat shows a maximum as a function of temperature, and the height of the maximum increases sharply at high magnetic fields. Although all the three systems show qualitatively similar behavior, there are some notable quantitative differences between the systems in which the site spin difference, $|s_1 - s_2|$, is large and small respectively.Comment: 16 LaTeX pages, 13 postscript figure

The airborne laser ranging system, its capabilities and applications

The airborne laser ranging system is a multibeam short pulse laser ranging system on board an aircraft. It simultaneously measures the distances between the aircraft and six laser retroreflectors (targets) deployed on the Earth's surface. The system can interrogate over 100 targets distributed over an area of 25,000 sq, kilometers in a matter of hours. Potentially, a total of 1.3 million individual range measurements can be made in a six hour flight. The precision of these range measurements is approximately + or - 1 cm. These measurements are used in procedure which is basically an extension of trilateration techniques to derive the intersite vector between the laser ground targets. By repeating the estimation of the intersite vector, strain and strain rate errors can be estimated. These quantities are essential for crustal dynamic studies which include determination and monitoring of regional strain in the vicinity of active fault zones, land subsidence, and edifice building preceding volcanic eruptions

Effects of specimen resonances on acoustic-ultrasonic testing

The effects of specimen resonances on acoustic ultrasonic (AU) nondestructive testing were investigated. Selected resonant frequencies and the corresponding normal mode nodal patterns of the aluminum block are measured up to 75.64 kHz. Prominent peaks in the pencil lead fracture and sphere impact spectra from the two transducer locations corresponded exactly to resonant frequencies of the block. It is established that the resonant frequencies of the block dominated the spectral content of the output signal. The spectral content of the output signals is further influenced by the transducer location relative to the resonant frequency nodal lines. Implications of the results are discussed in relation to AU parameters and measurements

Anisotropy effects in a mixed quantum-classical Heisenberg model in two dimensions

We analyse a specific two dimensional mixed spin Heisenberg model with exchange anisotropy, by means of high temperature expansions and Monte Carlo simulations. The goal is to describe the magnetic properties of the compound (NBu_{4})_{2}Mn_{2}[Cu(opba)]_{3}\cdot 6DMSO\cdot H_{2}O which exhibits a ferromagnetic transition at $T_{c}=15K$. Extrapolating our analysis on the basis of renormalisation group arguments, we find that this transition may result from a very weak anisotropy effect.Comment: 8 pages, 10 Postscript figure

Precise tracking of the Magellan and Pioneer Venusorbiters by same-beam interferometry. Part 1: Dataaccuracy analysis

Simultaneous tracking of two spacecraft in orbit about a distant planet by two widely separated Earth-based radio antennas provides more-accurate positioning information than can be obtained by tracking each spacecraft separately. A demonstration of this tracking technique, referred to as same-beam interferometry (SBI), is currently being done using the Magellan and Pioneer 12 orbiters at Venus. Signals from both spacecraft fall within the same beamwidth of the Deep Space Station antennas. The plane-of-sky position difference between spacecraft is precisely determined by doubly differenced phase measurements. This radio metric measurement naturally complements line-of-sight Doppler. Data was first collected from Magellan and Pioneer 12 on August 11-12, 1990, shortly after Magellan was inserted into Venus orbit. Data were subsequently acquired in February and April 1991, providing a total of 34 hours of same-beam radio metric observables. Same-beam radio metric residuals have been analyzed and compared with model measurement error predictions. The predicted error is dominated by solar plasma fluctuations. The rms of the residuals is less than predicted by about 25 percent for 5-min averages. The shape of the spectrum computed from residuals is consistent with that derived from a model of solar plasma fluctuations. This data type can greatly aid navigation of a second spacecraft when the first is well-known in its orbit