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781.
Automatic dependent surveillance-broadcast (ADS-B) is gaining acceptance around the world as the next-generation surveillance technology. It can provide surveillance to air traffic controllers to support today's procedures as well as surveillance in the cockpit to support air-to-air applications. Pilots and ground personnel have begun to benefit from this technology but further benefits from technological improvements can still be realized. These improvements include security, increased data capacity, and advanced applications (4D trajectory and data exchange). To this end research is currently being performed by Sensis Corporation in cooperation with NASA Glenn research center to provide enhancements to the ADS-B UAT (universal access transceiver) data link. The research goal is to encourage user acceptance by improving upon existing capability and usability along with providing a roadmap and demonstrations of future data link capability  相似文献   
782.
This paper considers the state-of-the-art information technologies applied to solve the automatic track-keeping problem of the ship on a preset system of straight tacks and on a preset route to the area of hydrographic survey. A navigation-and-controlling system aboard a hydrographic vessel GS-439 was used to provide the fulfillment of the task. The results of the sea trials of control problems are given. They have shown rather good accuracy of the ship track-keeping on a preset system of straight tacks and on a preset route as well as the efficiency of automatic ship passing to the first tack and passing over to the next tacks in surveying the seabed relief, using a multi-channel echo sounder  相似文献   
783.
The Advanced Thin Ionization Calorimeter (ATIC) experiment is designed to investigate the charge composition and energy spectra of primary cosmic rays over the energy range from about 1011 to 1014 eV during Long Duration Balloon (LDB) flights from McMurdo, Antarctica. Currently, analysis from the ATIC-1 test flight and ATIC-2 science flight is underway and preparation for a second science flight is in progress. Charge identification of the incident cosmic ray is accomplished, primarily, by a pixilated Silicon Matrix detector located at the very top of the instrument. While it has been shown that the Silicon Matrix detector provides good charge identification even in the presence of electromagnetic shower backscatter from the calorimeter, the detector only measures the charge once. In this paper, we examine use of the top scintillator hodoscope detector to provide a second measure of the cosmic ray charge and, thus, improve the ATIC charge identification.  相似文献   
784.
The Cosmic-Ray Energetics And Mass balloon-borne experiment has been launched twice in Antarctica, first in December 2004 and again in December 2005. It circumnavigated the South Pole three times during the first flight, which set a flight duration record of 42 days. A cumulative duration of 70 days within 13 months was achieved when the second flight completed 28 days during two circumnavigations of the Pole on 13 January 2006. Both the science instrument and support systems functioned extremely well, and a total 117 GB of data including 67 million science events were collected during these two flights. Preliminary analysis indicates that the data extend well above 100 TeV and follow reasonable power laws. The payload recovered from the first flight has been refurbished for the third flight in 2007, whereas the payload from the second flight is being refurbished to be ready for the fourth flight in 2008. Each flight will extend the reach of precise cosmic-ray composition measurements to energies not previously possible.  相似文献   
785.
The algorithms of controlled descent for unmanned winged gliders are designed taking into account the requirements to the flight trajectory. The calculation results are represented to show the efficiency of the algorithms.  相似文献   
786.
This paper considers the purpose, principles of construction, algorithms of generating output signals and the functional diagram of a simulator of aircraft air signals that is built based on the vortex sensor of aerodynamic angle and true airspeed.  相似文献   
787.
Differences in the isotope content of the biogenous chemicals of cosmonaut habitats are given a theoretical consideration. Rationale is given to the hypothesis according to which the biochemical and biophysical processes in plants. animals, and humans must be impacted by the isotopes of all the biogenous chemicals in cosmonaut habitats. Organisms were found to persistently make preference of lighter fractions of stable isotopes from the biogenous chemicals. In most of the compounds the light fraction of stable isotopes constitutes the greater portion by mass. However, the optimal isotope composition of biogenous chemicals is still unknown and necessitates biochemical, toxicological, biological and other kinds of research. The functions of a life support system should also include production and maintenance of an optimal isotope composition for habitats, i.e. water, oxygen, food stuffs in order to improve metabolism in and performance of cosmonauts.  相似文献   
788.
In this paper, some features of cavity development are presented for a case of a flow around the blade profile of the centrifugal pump impeller. Based on the photographs obtained in visualization of the cavitation centrifugal pump operation conditions, we refined the shape, volumes, and parameters of cavity growth in the centrifugal pump flow passage. Also presented are the relations characterizing the features of cavity formation in the centrifugal force field.  相似文献   
789.
Many radar systems now employ wideband waveforms and noncoherent averaging techniques to reduce the scintillation of the backscatter from ground clutter. The purpose of this paper is to quantify the effects of the wideband spectral shape on the clutter standard deviation after noncoherent averaging of the received signal. Relationships are developed which quantify the clutter standard deviation for any spectral shape and any ratio of transmitted band-width to processed bandwidth.  相似文献   
790.
An inverse filter, contained in a recently published paper by Senmoto and Childers, is improved by the application of a shaping function derived by Turin in an earlier paper.  相似文献   
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