PAN AIR analysis of the NASA/MCAIR 279-3: An advanced supersonic V/STOL fighter/attack aircraft

PAN AIR is a computer program for predicting subsonic or supersonic linear potential flow about arbitrary configurations. The program was applied to a highly complex single-engine-cruise V/STOL fighter/attack aircraft. Complexities include a close-coupled canard/wing, large inlets, and four exhaust nozzles mounted directly under the wing and against the fuselage. Modeling uncertainties involving canard wake location and flow-through approximation through the inlet and the exhaust nozzles were investigated. The recently added streamline capability of the program was utilized to evaluate visually the predicted flow over the model. PAN AIR results for Mach numbers of 0.6, 0.9, and angles of attack of 0, 5, and 10 deg. were compared with data obtained in the Ames 11- by 11-Foot Transonic Wind tunnel, at a Reynolds number of 3.69 x 10 to the 6th power based on c bar

Hypersonic test facility Patent

Hypersonic test facility for studying ablation in models under high pressure and high temperatur

Recognition map analysis and crop acreage estimation using Skylab EREP data

There are no author-identified significant results in this report

Recognition map analysis and crop acreage estimation

There are no author-identified significant results in this report

Research in satellite-aided crop inventory and monitoring

Automated information extraction procedures for analysis of multitemporal LANDSAT data in non-U.S. crop inventory and monitoring are reviewed. Experiments to develope and evaluate crop area estimation technologies for spring small grains, summer crops, corn, and soybeans are discussed

Roughrider... A Winterhard, High Yielding Hard Red Winter Wheat Variety

Roughrider is higher yielding and more lodging resistant than either Froid or Winoka, the two most popular winter wheat varieties in North Dakota. It is heavier in test weight, earlier maturing and shorter than Froid. Its winterhardiness is similar to Froid and superior to Winoka. The name "Roughrider" was taken from the association with President Theodore Roosevelt, who ranched in western North Dakota where this variety is well adapted

Evidence for nodal superconductivity in LaFePO

In several iron-arsenide superconductors there is strong evidence for a fully gapped superconducting state consistent with either a conventional s-wave symmetry or an unusual $s_\pm$ state where there the gap changes sign between the electron and hole Fermi surface sheets. Here we report measurements of the penetration depth $\lambda(T)$ in very clean samples of the related iron-phosphide superconductor, LaFePO, at temperatures down to $\sim$ 100 mK. We find that $\lambda(T)$ varies almost perfectly linearly with $T$ strongly suggesting the presence of gap nodes in this compound. Taken together with other data, this suggests the gap function may not be generic to all pnictide superconductors

An Exact Prediction of N=4 SUSYM Theory for String Theory

We propose that the expectation value of a circular BPS-Wilson loop in N=4 SUSYM can be calculated exactly, to all orders in a 1/N expansion and to all orders in g^2 N. Using the AdS/CFT duality, this result yields a prediction of the value of the string amplitude with a circular boundary to all orders in alpha' and to all orders in g_s. We then compare this result with string theory. We find that the gauge theory calculation, for large g^2 N and to all orders in the 1/N^2 expansion does agree with the leading string theory calculation, to all orders in g_s and to lowest order in alpha'. We also find a relation between the expectation value of any closed smooth Wilson loop and the loop related to it by an inversion that takes a point along the loop to infinity, and compare this result, again successfully, with string theory.Comment: LaTeX, 22 pages, 3 figures. Argument corrected and two new sections adde

An intelligent, free-flying robot

The ground based demonstration of the extensive extravehicular activity (EVA) Retriever, a voice-supervised, intelligent, free flying robot, is designed to evaluate the capability to retrieve objects (astronauts, equipment, and tools) which have accidentally separated from the Space Station. The major objective of the EVA Retriever Project is to design, develop, and evaluate an integrated robotic hardware and on-board software system which autonomously: (1) performs system activation and check-out; (2) searches for and acquires the target; (3) plans and executes a rendezvous while continuously tracking the target; (4) avoids stationary and moving obstacles; (5) reaches for and grapples the target; (6) returns to transfer the object; and (7) returns to base

Computer Aided Analysis, Planning, and Control of Space Systems Operations

The complexity and operational dynamics of modern space systems has dictated a need for computerized tools to assist in the analysis, planning, and control of space system operations. Three computer programs (ACTNET, TLGEN, and WICK 9) which have been applied successfully to these problems are discussed in this paper. ACTNET is a second generation discrete-event simulation system designed for the functional analysis of complex processes. It is applicable to systems which may be modeled as networks of activities that are constrained by precedence, logical conditions, and limited resources. ACTNET has been employed within the Nuclear Stage, Space Station, and Space Shuttle programs by MDAC-West. TLGEN is a computer program currently under development by MDAC-West for generating operational mission timelines. In its batch mode of operation, it is used for planning on-orbit operations. In its interactive (on-line) mode, it can support real-time control of on-orbit operations by mission control/ground system personnel. TLGEN is designed for scheduling detailed sequences of events subject to event duration time, execution time, priority, resource usage, and environmental constraints (ephemeris)