Means for measuring the electron density gradients of the plasma sheath formed around a space vehicle Patent

Development of method for measuring electron density gradients of plasma sheath around space vehicle during atmospheric entr

WHAT'S SPACE GOT TO DO WITH IT? DISTANCE AND AGRICULTURAL PRODUCTIVITY BEFORE THE RAILWAY AGE

Owing to the high cost of transporting farm produce before the railway age, the land-intensiveness of European mixed farming caused both production and consumption of foodstuffs and intermediate farm inputs in the steady state to be highly dispersed, a spatial configuration offering weak inducement to reorganize farm structure or to invest available labour and capital with a view to increasing output. In such conditions the most common cause of rising agricultural productivity was spatial concentration of demand, which raised the demand price of farm produce and farm inputs within the privileged space bounded by discontinuities in the cost of land transport. The ultimate cause of observed changes in agricultural productivity before the nineteenth century must therefore be sought outside the farming sector in the development of markets for tradable manufactures, tradable services, and the economies of scale in their provision that supported spatial concentration of population.

Preliminary ISIS users manual

The Interactive Software Invocation (ISIS), an interactive data management system, was developed to act as a buffer between the user and host computer system. The user is provided by ISIS with a powerful system for developing software or systems in the interactive environment. The user is protected from the idiosyncracies of the host computer system by providing such a complete range of capabilities that the user should have no need for direct access to the host computer. These capabilities are divided into four areas: desk top calculator, data editor, file manager, and tool invoker

Comparison of flying qualities derived from in-flight and ground-based simulators for a jet-transport airplane for the approach and landing pilot tasks

The primary objective was to provide information to the flight controls/flying qualities engineer that will assist him in determining the incremental flying qualities and/or pilot-performance differences that may be expected between results obtained via ground-based simulation (and, in particular, the six-degree-of-freedom Langley Visual/Motion Simulator (VMS)) and flight tests. Pilot opinion and performance parameters derived from a ground-based simulator and an in-flight simulator are compared for a jet-transport airplane having 32 different longitudinal dynamic response characteristics. The primary pilot tasks were the approach and landing tasks with emphasis on the landing-flare task. The results indicate that, in general, flying qualities results obtained from the ground-based simulator may be considered conservative-especially when the pilot task requires tight pilot control as during the landing flare. The one exception to this, according to the present study, was that the pilots were more tolerant of large time delays in the airplane response on the ground-based simulator. The results also indicated that the ground-based simulator (particularly the Langley VMS) is not adequate for assessing pilot/vehicle performance capabilities (i.e., the sink rate performance for the landing-flare task when the pilot has little depth/height perception from the outside scene presentation)

Large aircraft handling qualities

The short period frequency requirements of MIL-F-8785C are applicable to the very large transport aircraft simulated. The large aircraft simulated meet the requirements of NASA CR-159236 for effective time delay and pitch transient peak ratio. However, the requirements of this reference for the effective rise time parameter are believed to be too convservative for very large transport aircraft. Data obtained to date as well as other data indicate that MIL-SPEC requirements for the parameter t(phi=30 degrees) are too conservative for very large transport aircraft. The results of the present study indicate that t(phi=30 degrees) of less than 6 sec should result in ""acceptable'' roll response characteristics, and t(phi=30 degrees) of less than 4.0 sec should result in ""satisfactory'' roll response

Antenna design for surface wave suppression Patent

Development of method for suppressing excitation of electromagnetic surface waves on dielectric converter antenn

Web interfaces to enhance CAL materials: Case studies from law and statistics

One impact of the ‘information age’ is that a variety of new learning resources have become available to both students and tutors. Using these resources effectively and with a sound pedagogical basis presents a whole array of issues for teaching professionals. In this paper the authors describe the development and implementation of a Web interface to existing computer‐based learning materials in an attempt to enhance the student learning experience. Although the innovations occurred in two very different disciplines ‐statistics and law ‐ there are common lessons to be learned about the process of learning and the use of technology

Analytical study of effects of severe turbulence on flight motions of a typical subsonic jet-transport airplane

Atmospheric turbulence effects on stability and response characteristics of subsonic jet transport aircraf