13,296 research outputs found
Closing the design loop on HiMAT (highly maneuverable aircraft technology)
The design methodology used in the HiMAT program and the wind tunnel development activities are discussed. Selected results from the flight test program are presented and the strengths and weaknesses of testing advanced technology vehicles using the RPV concept is examined. The role of simulation on the development of digital flight control systems and in RPV's in particular is emphasized
The economic value of remote sensing of earth resources from space: An ERTS overview and the value of continuity of service. Volume 5: Inland water resources
The economic value of an ERTS system in the area of inland water resources management is investigated. Benefits are attributed to new capabilities for managing inland water resources in the field of power generation, agriculture, and urban water supply. These benefits are obtained in the area of equal capability (cost savings) and increased capability (equal budget), and are estimated by applying conservative assumptions to Federal budgeting information, Congressional appropriation hearings, and ERTS technical capabilities
A parametric study of the value of hydrological information for irrigation and hydropower management of the Feather River
A case study analysis is presented of the relationships between improvements in the accuracy, frequency, and timeliness of information used in making hydrological forecasts and economic benefits in the areas of hydropower and irrigation. The area chosen for the case study is the Oroville Dam and Reservoir. Emphasis is placed on the use of timely and accurate mapping of the aerial extent of snow in the basin by earth resources survey systems such as LANDSAT. The subject of benefits resulting from improved runoff forecasts is treated in a generalized way without specifying the source of the improvements
The nature of antiplatelet activity in antilymphoblast ALG--with special reference to cross-reacting antibody, immunochemical characterization, and Coombs' positive thrombocytopenia in ALG-treated renal recipients.
On embedding of the Bratteli diagram into a surface
We study C*-algebras O_{\lambda} which arise in dynamics of the interval
exchange transformations and measured foliations on compact surfaces. Using
Koebe-Morse coding of geodesic lines, we establish a bijection between Bratteli
diagrams of such algebras and measured foliations. This approach allows us to
apply K-theory of operator algebras to prove strict ergodicity criterion and
Keane's conjecture for the interval exchange transformations.Comment: final versio
One Man\u27s Reaction to NATO Expansion
Using the policy of NATO expansion and the events of the Ukraine crisis, this paper examines President Vladimir Putin’s impact on Russian foreign policy and analyzes the extent to which his personality and personal interests have shaped Russia’s actions. In doing so, it seems that Russia as an actor on the international stage cannot be understood without considering Putin’s role in creating what Russia is today
Infections Complicating Orthotopic Liver Transplantation: A Study Emphasizing Graft-Related Septicemia
In 93 recipients of 102 orthotopic liver homografts, the incidence of bacteremia or fungemia exceeded 70%. The graft itself was usually an entry site for systemic infection after both immunologic and nonimmunologic parenchymal injury, especially if there was defective biliary drainage. The role of the homograft itself as the special infectious risk factor has prompted increased use of defunctionalized jejunal Roux limbs to reduce graft contamination. It has also stimulated very aggressive postoperative diagnostic efforts to rule out remedial mechanical complications of the transplant. © 1976, American Medical Association. All rights reserved
Predicted efficiency of Si wire array solar cells
Solar cells based on arrays of CVD-grown Si nano- or micro-wires have attracted interest as potentially low-cost alternatives to conventional wafer-based Si photovoltaics [1-6], and single-wire solar cells have been reported with efficiencies of up to 3.4% [7]. We recently presented device physics simulations which predicted efficiencies exceeding 17%, based on experimentally observed diffusion lengths within our wires [8]. However, this model did not take into account the optical properties of a wire array device - in particular the inherently low packing fraction of wires within CVD-grown wire arrays, which might limit their ability to fully absorb incident sunlight. For this reason, we have combined a device physics model of Si wire solar cells with FDTD simulations of light absorption within wire arrays to investigate the potential photovoltaic efficiency of this cell geometry. We have found that even a sparsely packed array (14%) is expected to absorb moderate (66%) amounts of above-bandgap solar energy, yielding a simulated photovoltaic efficiency of 14.5%. Because the wire array comprises such a small volume of Si, the observed absorption represents an effective optical concentration, which enables greater operating voltages than previously predicted for Si wire array solar cells
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