The Mark 3 Haploscope

A computer-operated binocular vision testing device was developed as one part of a system designed for NASA to evaluate the visual function of astronauts during spaceflight. This particular device, called the Mark 3 Haploscope, employs semi-automated psychophysical test procedures to measure visual acuity, stereopsis, phoria, fixation disparity, refractive state and accommodation/convergence relationships. Test procedures are self-administered and can be used repeatedly without subject memorization. The Haploscope was designed as one module of the complete NASA Vision Testing System. However, it is capable of stand-alone operation. Moreover, the compactness and portability of the Haploscope make possible its use in a broad variety of testing environments

Approximate Analytic Solution for the Spatiotemporal Evolution of Wave Packets undergoing Arbitrary Dispersion

We apply expansion methods to obtain an approximate expression in terms of elementary functions for the space and time dependence of wave packets in a dispersive medium. The specific application to pulses in a cold plasma is considered in detail, and the explicit analytic formula that results is provided. When certain general initial conditions are satisfied, these expressions describe the packet evolution quite well. We conclude by employing the method to exhibit aspects of dispersive pulse propagation in a cold plasma, and suggest how predicted and experimental effects may be compared to improve the theoretical description of a medium's dispersive properties.Comment: 17 pages, 4 figures, RevTe

Solar energy : a summary of records at Columbia, Missouri

Digitized 2007 AES.Includes bibliographical references (page 26)

Effect of gaseous and solid simulated jet plumes on an 040A space shuttle launch configuration at m=1.6 to 2.2

The effect of plume-induced flow separation and aspiration effects due to operation of both orbiter and the solid rocket motors on a 0.019-scale model of the launch configuration of the Space Shuttle Vehicle is determined. Longitudinal and lateral-directional stability data were obtained at Mach numbers of 1.6, 2.0, and 2.2 with and without the engines operating. The plumes exiting from the engines were simulated by a cold-gas jet supplied by an auxiliary 200-atm air supply system and solid-body plume simulators. The aerodynamic effects produced by these two simulation procedures are compared. The parameters most significantly affected by the jet plumes are pitching moment, elevon control effectiveness, axial force, and orbiter wing loads. The solid rocket motor (SRM) plumes have the largest effect on the aerodynamic characteristics. The effect of the orbiter plumes in combination with the SRM plumes is also significant. Variations in the nozzle design parameters and configuration changes can reduce the jet plume-induced aerodynamic effects

Climate of the southeast lowlands of Missouri

Cover title

Space shuttle abort separation pressure investigation. Volume 2, Part B: Orbiter data at Mach 5

For abstract, see

A Probable Neoceratopsian Manus Track from the Nanushuk Formation (Albian, Northern Alaska)

We report a likely neoceratopsian manus track from an exposure of the Nanushuk Formation along the Colville River in northern Alaska. The track described here containts the impressions of five digits, arranged as an arc, which identify this specimen as a manus. Details of the impression suggest that it is neoceratopsian rather than ankylosaurian. The length of the chord of the arc of the track is approximately 25 cm, which is half the size of manus tracks found west of Denver, Colorado, USA attributed to the 10 m long Maastrichtian Triceratops. The Nanushuk Formation is a succession of complexly intertonguing marine and nonmarine strata interpreted as shelf, deltaic, strandplain, fluvial, and alluvial overbank deposits. Deposited in the foreland basin north f the Brooks Range, the rock unit is present throughout most of the northern foothills belt and subsurface of the central and western North Slope coastal plain. Fossil and radiometric data place outcrop within the Albian. If the identification of the track is correct, this is one of the earlies occurrences of neoceratopsians from North America. The occurrence of this track in Alaska substantiates the biogeographic model of faunal exchange between Asia and North America through a Cretaceous land bridge known as Beringia.Presentamos una probable huella de mano atribuida a neoceratopsido de un afloramiento de la Formación Nanushuk a lo largo del río Colville, en el norte de Alaska. La huella descrita contiene la impresión de cinco dígitos, dispuestos en arco, que identifican este especimen como una mano. Los detalles de la impresion sugieren que se trata de un neoceratopsido mas que de un ankilosaurio. La longitud de la cuerda del arco de la huella es aproximadamente de 25 cm, lo cual es la mitad del tamano de las huellas de mano encontradas al oeste de Denver, Colorado, EE.UU, y atribuidas a Triceratops, un taxon de unos 10 m de largo de edad Maastrichtiense. La Formacion Nanushuk es una sucesion de capas de origen marino y no marino complejamente interdigitadas e interpretadas como depósitos de plataforma, deltaicos de playas progradantes, fluviales y de overbank aluvial. Depositada en una cuenca de antepais al norte del Brooks Range, la unidad de roca esta presente a lo largo de la mayor parte de la franja septentrional de colinas, y en el subsuelo de la zona central y occidental, de la llanura costera de North Slope. Los fosiles y los datos radiometricos situan este afloramiento en el Albiense. Si la identificación de la huella es correcta, es una de las apariciones más tempranas de neoceratopsidos en Norteamaerica. La aparición de esta huella en Alaska apoya el modelo biogeográfico de intercambio faunístico entre Asia y Norteamerica a traves de un puente de tierra cretacico conocido como Beringia

Usual energy and macronutrient intakes in 2-9-year-old European children

OBJECTIVE: Valid estimates of population intakes are essential for monitoring trends as well as for nutritional interventions, but such data are rare in young children. In particular, the problem of misreporting in dietary data is usually not accounted for. Therefore, this study aims to provide accurate estimates of intake distributions in European children. DESIGN: Cross-sectional setting-based multi-centre study. SUBJECTS: A total of 9560 children aged 2-9 years from eight European countries with at least one 24-h dietary recall (24-HDR). METHODS: The 24-HDRs were classified in three reporting groups based on age- and sex-specific Goldberg cutoffs (underreports, plausible reports, overreports). Only plausible reports were considered in the final analysis (N=8611 children). The National Cancer Institute (NCI)-Method was applied to estimate population distributions of usual intakes correcting for the variance inflation in short-term dietary data. RESULTS: The prevalence of underreporting (9.5%) was higher compared with overreporting (3.4%). Exclusion of misreports resulted in a shift of the energy and absolute macronutrient intake distributions to the right, and further led to the exclusion of extreme values, that is, mean values and lower percentiles increased, whereas upper percentiles decreased. The distributions of relative macronutrient intakes (% energy intake from fat/carbohydrates/proteins) remained almost unchanged when excluding misreports. Application of the NCI-Method resulted in markedly narrower intake distributions compared with estimates based on single 24-HDRs. Mean percentages of usual energy intake from fat, carbohydrates and proteins were 32.2, 52.1 and 15.7%, respectively, suggesting the majority of European children are complying with common macronutrient intake recommendations. In contrast, total water intake (mean: 1216.7 ml per day) lay below the recommended value for >90% of the children. CONCLUSION: This study provides recent estimates of intake distributions of European children correcting for misreporting as well as for the daily variation in dietary data. These data may help to assess the adequacy of young children's diets in Europe

Nanocrystalline n Type Silicon Front Surface Field Layers From Research to Industry Applications in Silicon Heterojunction Solar Cells

Nanocrystalline silicon and silicon oxide nc Si Ox H layers grown by plasma enhanced chemical vapor deposition PECVD have shown low parasitic absorption and excellent contact properties when implemented as n type front surface field FSF contact in rear junction silicon heterojunction SHJ solar cells [1 3]. In this contribution we present results from the successful process transfer from the lab at PVcomB at the Helmholtz Zentrum Berlin HZB , to the industrial pilot line at Meyer Burger Germany GmbH MBG . Conversion efficiencies gt; 22.5 were demonstrated on SHJ cell 4 cm2 [2, 3]. The excellent cell performance in the lab and the potential to reduce parasitic absorption in the front stack by using nc SiOx H motivated the process transfer from HZB to MBG. Initial cross processing experiments on 244 cm2 wafers showed the benefit of using nc Si H as FSF layer. We here also emphasize the role of the Si texture on a fast nc Si H nucleation. After cross processing experiments a successful transfer of the nc Si H process and fine tuning resulted in a median cell efficiency of 23.4 . This is in the same range as the MGB reference on 244 cm2 cells, noteworthy, at the same throughput. Currently work is ongoing to further improve the optical performance of the cells by adding oxygen CO

Mirror symmetry breaking as a problem in dynamical critical phenomena

The critical properties of the Frank model of spontaneous chiral synthesis are discussed by applying results from the field theoretic renormalization group (RG). The long time and long wavelength features of this microscopic reaction scheme belong to the same universality class as multi-colored directed percolation processes. Thus, the following RG fixed points (FP) govern the critical dynamics of the Frank model for d<4: one unstable FP that corresponds to complete decoupling between the two enantiomers, a saddle-point that corresponds to symmetric interspecies coupling, and two stable FPs that individually correspond to unidirectional couplings between the two chiral molecules. These latter two FPs are associated with the breakdown of mirror or chiral symmetry. In this simplified model of molecular synthesis, homochirality is a natural consequence of the intrinsic reaction noise in the critical regime, which corresponds to extremely dilute chemical systems.Comment: 9 pages, 3 figure