Modular space station phase B extension period executive summary

A narrative summary is presented of technical, programmatic, and planning information developed during the space station definition study extension period. The modular space station is emphasized, but tasks pertaining to shuttle sorties missions and information management advanced development are included. A series of program options considering technical, schedule, and programmatic alternatives to the baseline program are defined and evaluated

Helistat simulation studies

An analysis of the flight dynamics and piloted control characteristics of the Helistat, a quadrotor heavy-lift airship, was completed using the HYBRDS airship simulation facility. The analysis covered the full operating flight envelope, including likely ranges of altitude, airspeed, sideslip, and loading variations. Particular areas of study were performance, trim, power requirements, linearized dynamics, handling qualities, and mooring operations. The key assumptions were: a rigid vehicle, no control system dynamics, fixed rotor and propeller RPM, and no ballonet dynamics. The nominal cruise speed for the H34 engines operating at 1275 HP was found to be 40-50 kts, depending on the loading condition. The maximum payload capability was calculated as 45,000 lbs for sea level-based operations. The crosswind capability in hover is 5-10 kts depending on the loading conditions, but this requires excessive roll angle due to the roll-to-translate control gearing. Sideslip angles of 110-135 degrees (wind from aft quarters) are critical for directional trim and stability, and should be avoided

Breaking Ranks: GI Antiwar Newspapers and the Culture of Protest

An overview of anti-war publications produced by American servicemen in the Vietnam War era

The gallery as therapeutic venue: exploring visitor perceptions in a contemporary space

This prospective qualitative study explored the social and psychological impact of an exhibition at a contemporary art gallery. Three focus groups, including 8 people aged 45-69, were held following a guided tour of an exhibition at Nottingham Contemporary gallery. The exhibition Uneven Geographies featured the works of a variety of international artists focussing upon the politics of globalisation through different media including film, installation and photography. Focus group transcripts were analysed using Braun and Clarke’s 6-phase model of thematic analysis. Three themes were identified: 1) ’It’s almost like a piece of a jigsaw puzzle’, 2) Interpreting the Message and 3) Dissolving Social Barriers. Results indicated that the exhibition helped participants make sense of a variety of experiences, art interpretation was a key educational skill, and attending the gallery promoted social inclusion. These findings build on previous studies that indicate the potential for cultural institutions, such as art galleries and museums, to promote education, health and wellbeing at individual and societal levels

Scattering in Multilayered Structures: Diffraction from a Nanohole

The spectral expansion of the Green's tensor for a planar multilayered structure allows us to semi analytically obtain the angular spectrum representation of the field scattered by an arbitrary dielectric perturbation present in the structure. In this paper we present a method to find the expansion coefficients of the scattered field, given that the electric field inside the perturbation is available. The method uses a complete set of orthogonal vector wave functions to solve the structure's vector wave equation. In the two semi-infinite bottom and top media, those vector wave functions coincide with the plane-wave basis vectors, including both propagating and evanescent components. The technique is used to obtain the complete angular spectrum of the field scattered by a nanohole in a metallic film under Gaussian illumination. We also show how the obtained formalism can easily be extended to spherically and cylindrically multilayered media. In those cases, the expansion coefficients would multiply the spherical and cylindrical vector wave functions.Comment: 9 pages, 5 figure

Flight dynamics analysis and simulation of heavy lift airships. Volume 1: Executive summary

A generic, yet comprehensive mathematical model and computer simulation of the HLA flight dynamics over its entire flight envelope was developed. Implicit in this simulation development are the data reviews and analyses which support the equations of motion and the calculation of forces and moments acting on the vehicle. The simulation, HYBRDS, is addressed to the broad requirements and is intended for use as a synthesis and analysis tool for the evaluation of competing HLA design concepts

Flight dynamics analysis and simulation of heavy lift airships. Volume 5: Programmer's manual

The Programmer's Manual contains explanations of the logic embodied in the various program modules, a dictionary of program variables, a subroutine listing, subroutine/common block/cross reference listing, and a calling/called subroutine cross reference listing

Quantifying the Mulligan River Pituri, Duboisia hopwoodii ((F. Muell.) F.Muell.) (Solanaceae), trade of Central Australia

Pituri (Duboisia hopwoodii (F. Muell.) F. Muell.) (Solanaceae) is a narcotic shrub which grows in the parallel dune fields of the Simpson Desert of far south-western Queensland, Australia. The ethnographic literature points to an impressive scale of trade of pituri between Aboriginal groups across inland eastern Australia, and suggests total annual production of 2500-3000 kg of dried plant material. However, there has been no attempt to assess the feasibility of these figures, or investigate the number of pituri plants required to sustain such a scale of trade. We mapped the distribution and density of D. hopwoodii along four one km wide transects, totally 130 km in length. Our results suggest that the population of pituri west of the Mulligan River could number around 36,000 mature plants. Ninety randomly selected plants were measured, and the foliage of six of these was harvested and dried. Plants yielded between 0.15 and 6.68 kg of dry matter. Our 90 measured plants would have yielded around 155 kg of dried pituri. Therefore, between 1450 and 1740 plants would be required to sustain the purported level of trade and use. With knowledge of the location of dense pituri groves and highly efficient expeditions, harvesting this number of plants is feasible. However, numerous questions remain surrounding the ecological and ethnographic aspects of the pituri trade

Measurement and shaping of biphoton spectral wavefunctions

In this work we present a simple method to reconstruct the complex spectral wavefunction of a biphoton, and hence gain complete information about the spectral and temporal properties of a photon pair. The technique, which relies on quantum interference, is applicable to biphoton states produced with a monochromatic pump when a shift of the pump frequency produces a shift in the relative frequencies contributing to the biphoton. We demonstrate an example of such a situation in type-II parametric down-conversion (SPDC) allowing arbitrary paraxial spatial pump and detection modes. Moreover, our test cases demonstrate the possibility to shape the spectral wavefunction. This is achieved by choosing the spatial mode of the pump and of the detection modes, and takes advantage of spatiotemporal correlations.Comment: Supplementary information also available. Comments and feedback appreciated. Compared to the previous version, here we have made the following changes: -corrected a typo in the text between Eq. (11) and (12) -corrected a typo in the references -added reference