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891.
A flight test of a diode-pumped solid-state 2 μm Doppler Light Detection And Ranging (LIDAR) system was conducted on-board the NASA Ames DC-8 Airborne Laboratory. This was the first ever airborne demonstration of a 2 μm diode-pumped solid-state Doppler LIDAR. The LIDAR performance was verified by comparing the true-airspeed (TAS) estimate with that found using the pneumatic air data system; excellent agreement was found. The capabilities of this pulsed 2 μm Doppler LIDAR system include high bandwidth air data determination without the need for extensive forebody calibration, remote wind profiling as far as several kilometers away from the aircraft, eye-safe laser transmission at 2 μm, and diode-pumped solid-state design for compact construction and reliable performance  相似文献   
892.
The paper discusses the digital image processing system for NOAA/AVHRR data including Land applications — configured around VAX 11/750 host computer supported with FPS 100 Array Processor, Comtal graphic display and HP Plotting devices; wherein the system software for relational Data Base together with query and editing facilities, Man-Machine Interface using form, menu and prompt inputs including validation of user entries for data type and range; preprocessing software for data calibration, Sun-angle correction, Geometric Corrections for Earth curvature effect and Earth rotation offsets and Earth location of AVHRR image have been accomplished. The implemented image enhancement techniques such as grey level stretching, histogram equalization and convolution are discussed. The software implementation details for the computation of vegetative index and normalized vegetative index using NOAA/AVHRR channels 1 and 2 data together with output are presented; scientific background for such computations and obtainability of similar indices from Landsat/MSS data are also included. The paper concludes by specifying the further software developments planned and the progress envisaged in the field of vegetation index studies.  相似文献   
893.
As is well known in the F-region of the ionosphere modified by high power HF radio waves broad-band electromagnetic stimulated emission (SEE) is observed. It was discovered both the beams of superthermal electrons and intensive small-scale irregularities in modified region. These magnetic field aligned irregularities have caviton shape — deep electron density holes. The presence of such irregularities and superthermal electrons create conditions for generation of transition emission. We consider this radiation mechanism for interpretation the SEE broad-band component.  相似文献   
894.
895.
The intent of this tongue-in-cheek paper is to stimulate thought about technologies that may be included in future weapons systems and how the weapon system developer is impacted today. It explores a day in the life of a future generation fighter aircraft (year 2015-2025 time-frame). The scenario starts from the perspective of the ground crew awaiting the return of their future fighters: the new A/F-2, “Thunderchief II”-to a dispersed operations location (DOL) from a combat air patrol (CAP) mission in the fictitious country of Crad. A nonrestrictive technology view is assumed, tempered with as much realism as one can logically include in the scenario, with some of today's evolving technology thrusts  相似文献   
896.
897.
To estimate the risk resulting from exposures to ionizing radiation, the organ and tissue doses should be assessed. A convenient method is the calculation of these doses using representations of the human body, called models or phantoms, together with computer codes simulating the transport of radiation in the body. Most commonly used are mathematical phantoms whose external and internal volumes are defined by simple geometric bodies. More recently, phantoms constructed from computed tomographic data of real persons were introduced as an improvement. These phantoms present advantages concerning the location and shape of the organs, in particular the hard bone and bone marrow, whose distribution can be assessed with high resolution. So far, three of these phantoms were constructed at the GSF, a fourth is under process. The construction technique is described, and some calculational results of organ doses due to external photon irradiation are presented.  相似文献   
898.
We examined the peculiarities of the structure of the blood-vascular bed and perivascular cells in zones of osteogenesis in the epiphyses and metaphises of femoral bones of rats, flown aboard the US laboratory SLS-2 for two weeks by electron microscopy and histochemistry. In zones of bone remodeling, there was a tendency for a reduction of sinusoid capillary specific volume. Endotheliocytes preserve the typical structure. In the population of perivascular cells, we discovered differentiating osteogenic cells that contained alkaline phosphomonoesterase as well as cells that don't contain this enzyme and differentiate into fibroblasts. The fibroblasts genesis in zones of adaptive remodeling of spongy bones leads to a further development of fibrous tissue that is not subject to mineralization.  相似文献   
899.
Amelkin  N. I. 《Cosmic Research》2003,41(3):274-279
The systems of gyrodynes installed on a spacecraft body on the one-axis controlled platform are considered. An algorithm to determine the special states and the special surfaces corresponding to them in the region of variation of the total angular momentum is obtained, as well as an algorithm to study the permeability of special surfaces. The results of calculation of the special surfaces for two types of gyro systems are presented.  相似文献   
900.
Air defense systems protect land and maritime resources from air attack. Depending on the regional characteristics and type of conflicting forces, air defense threats vary considerably. In regional conflicts, where forces with similar capabilities are involved and no air-superiority can be achieved, the role of air defense systems becomes critical. In combat terrains containing mountains (in mainland or in small islands), the man-operated or computer-controlled (using passive sensors) anti-aircraft artillery can be highly effective. The simulator presented in this work aims to exploit the capabilities provided by current commercial-off-the-shelf (COTS) communication and multimedia technologies for providing a training environment that improves the personnel capability for effective use of man-controlled anti-aircraft weapons.  相似文献   
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