Man-computer role in space navigation and guidance Final report

Man computer roles and hardware requirements for navigation and guidance in deep space manned mission

Man-computer roles in space navigation and guidance, phase I

Estimated man-machine requirement computations for space navigation and guidanc

When the Disability Is Not the Problem - Experiencing the Barriers to Web Accessibility: The Experiences of Computer Users with Visual Disabilities Using the Internet

The purpose of this study is to describe the experiences and perceptions of three computer users with visual disabilities as they accessed and reviewed Web pages on the Internet. Attention is focused on the use of the Internet by individuals with visual disabilities: blindness, low vision, and deaf/blindness. Data were gathered through interviews and observation, during eight sessions with each participant. Data were qualitatively analyzed using an inductive process (Hatch, 2002). Data analysis revealed six categories of meaning: interactions with computer; personal characteristics, strategies to find solutions to barriers encountered; personal feeling and opinions; design features, and communication. Sites viewed included commercial, educational, non-profit, and governmental sites. Interviews consisted of structured and unstructured questions. The knowledge gained in this study will add to the literature of Web Accessibility and will contribute to raising awareness of the barriers that computer users with visual disabilities encounter when using the Internet

Higher-order Continuum Approximation for Rarefied Gases

The Hilbert-Chapman-Enskog expansion of the kinetic equations in mean flight times is believed to be asymptotic rather than convergent. It is therefore inadvisable to use lower order results to simplify the current approximation as is done in the traditional Chapman-Enskog procedure, since that is an iterative method. By avoiding such recycling of lower order results, one obtains macroscopic equations that are asymptotically equivalent to the ones found in the Chapman-Enskog approach. The new equations contain higher order terms that are discarded in the Chapman-Enskog method. These make a significant impact on the results for such problems as ultrasound propagation. In this paper, it is shown that these results turn out well with relatively little complication when the expansions are carried to second order in the mean free time, for the example of the relaxation or BGK model of kinetic theory.Comment: 20 pages, 2 figures, RevTeX 4 macro

Bound States of the Klein-Gordon Equation for Woods-Saxon Potential With Position Dependent Mass

The effective mass Klein-Gordon equation in one dimension for the Woods-Saxon potential is solved by using the Nikiforov-Uvarov method. Energy eigenvalues and the corresponding eigenfunctions are computed. Results are also given for the constant mass case.Comment: 13 page

Global shallow water magnetohydrodynamic waves in the solar tachocline

We derive analytical solutions and dispersion relations of global magnetic Poincar\'e (magneto-gravity) and magnetic Rossby waves in the approximation of shallow water magnetohydrodynamics. The solutions are obtained in a rotating spherical coordinate system for strongly and weakly stable stratification separately in the presence of toroidal magnetic field. In both cases magnetic Rossby waves split into fast and slow magnetic Rossby modes. In the case of strongly stable stratification (valid in the radiative part of the tachocline) all waves are slightly affected by the layer thickness and the toroidal magnetic field, while in the case of weakly stable stratification (valid in the upper overshoot layer of the tachocline) magnetic Poincar\'e and fast magnetic Rossby waves are found to be concentrated near the solar equator, leading to equatorially trapped waves. However, slow magnetic Rossby waves tend to concentrate near the poles, leading to polar trapped waves. The frequencies of all waves are smaller in the upper weakly stable stratification region than in the lower strongly stable stratification one