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11.
Sherry L. Brown C. Motazed B. Vos D. 《Aerospace and Electronic Systems Magazine, IEEE》2004,19(10):13-16
The attitude heading reference system (AHRS) provides data for primary flight instruments, head-up displays, autopilots, and moving map navigation systems. Advances in solid-state MEMS rate sensors, coupled with Kalman filter algorithms designed to mitigate high drift rates, provide the basis for low-cost, high-performance AHRS for general aviation. This paper describes the performance of a low cost, miniaturized AHRS using automotive-grade MEMS sensors. The performance of the system is detailed. The implications for certification of this class of system and fault tolerance are discussed. 相似文献
12.
This paper discusses and evaluates two innovative SETI education programs conducted at the University of Western Sydney, viz: the SETI Pathways Program and the Life in the Universe Curriculum Project. 相似文献
13.
14.
Bucci N.J. Nespor J.D. Urkowitz H. Mokry D. Brown R. Baldygo W. 《Aerospace and Electronic Systems Magazine, IEEE》1995,10(8):37-43
A major technology barrier to the application of pulse compression for the meteorological functions required by a next generation ATC radar is range/time sidelobes which mask and corrupt observations of weak phenomena occurring near areas of strong extended meteorological scatterers. Techniques for suppressing range sidelobes are well known but without prior knowledge of the scattering medium's velocity distribution their performance degrades rapidly in the presence of Doppler. Recent investigations have presented a “doppler tolerant” range sidelobe suppression technique. The thrust of the work described herein is the extension of previous simulations to actual transmitted dispersed/coded waveforms using the S-band surveillance radar located at Rome Laboratory Surveillance Facility. The objectives of the experiment are: 1) to extend the verification of the simulation of the Doppler tolerant technique; and 2) to demonstrate that the radar transmitter, waveform generator, and receiver imperfections do not significantly degrade resolution, performance or reliability of meteorological spectral moment estimates 相似文献
15.
Y Kitaya M Kiyota I Aiga K Yabuki K Nitta A Ikeda S Nakayama 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1992,12(5):37-40
In order to collect basic data about CO2 and O2 budgets of a plant cultural system in a CELSS, the variation of the CO2 absorption rates of lettuce and turnips were observed during the growing period, under different conditions. The O2 release rates were deduced from the CO2 absorption rates multiplied by 32/44. As a result, when the light intensity, the photoperiod and the atmospheric CO2 concentration increased, the rates also increased. The effects on the turnips were more significant than those on the lettuce. Turnips at 310 micromoles/m2/s of PPFD, 24 hours of photoperiod and 1100 ppm of CO2 concentration grew most actively in the present experimental conditions. One turnip absorbed 32.3 g CO2 and released 23.5 g O2 for 6 days between 24 days and 30 days after sowing. 相似文献
16.
Lipton A.J. Heartwell C.H. Haering N. Madden D. 《Aerospace and Electronic Systems Magazine, IEEE》2003,18(5):3-18
The latest generation of computer vision technology is revolutionizing concepts, applications, and products in video surveillance and CCTV. This is of prime relevance to security for large outdoor facilities such as commercial airfields, refineries, power plants, and office/industrial campuses. Most airfields, for example, have open (unfenced) perimeters, high volume heterogeneous traffic, are easily accessed on foot or by water, and exist in areas where regulations providing a safety buffer are difficult to legislate or enforce. And all airfields require 24/7 outdoor monitoring - snow, fog, rain, or shine. Likewise, most high-value facilities appealing to criminals and terrorists are in close proximity to public areas (roads, residences, city, etc.). The appeal of automated real-time surveillance is obvious $maximizing efficiency and effectiveness of security personnel and resources while increasing the probability of preventing a serious security breach. Computer vision based solutions have the potential for very discriminating detection and very low false alarms. The bottom line is that applied computer vision has the potential for the greatest return on investment (ROI), both short-term and long-term. 相似文献
17.
L. V. Zasova V. I. Moroz V. M. Linkin I. V. Khatuntsev B. S. Maiorov 《Cosmic Research》2006,44(4):364-383
The goal of this paper is to summarize the experimental data on the atmosphere of Venus obtained after 1985, when the VIRA (Venus International Reference Atmosphere) or COSPAR model was published. Among the most important results that have appeared since then are the following: measurements of the vertical temperature profile by the VEGA spacecraft with high precision and high altitude resolution; measurements made with balloons of the VEGA spacecraft; radio occultation measurements of Magellan, Venera-15, and Venera-16; and temperature profiles derived from the data of infrared spectrometry obtained by Venera-15. The new result as compared to VIRA is the creation of a model of the atmosphere in the altitude range 55 to 100 km dependent on local time. This model is presented in our paper in tabulated form. 相似文献
18.
D L Stephens L W Townsend J Miller C Zeitlin L Heilbronn 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2002,30(4):901-905
Deep-space manned flight as a reality depends on a viable solution to the radiation problem. Both acute and chronic radiation health threats are known to exist, with solar particle events as an example of the former and galactic cosmic rays (GCR) of the latter. In this experiment Iron ions of 1A GeV are used to simulate GCR and to determine the secondary radiation field created as the GCR-like particles interact with a thick target. A NASA prepared food pantry locker was subjected to the iron beam and the secondary fluence recorded. A modified version of the Monte Carlo heavy ion transport code developed by Zeitlin at LBNL is compared with experimental fluence. The foodstuff is modeled as mixed nuts as defined by the 71st edition of the Chemical Rubber Company (CRC) Handbook of Physics and Chemistry. The results indicate a good agreement between the experimental data and the model. The agreement between model and experiment is determined using a linear fit to ordered pairs of data. The intercept is forced to zero. The slope fit is 0.825 and the R2 value is 0.429 over the resolved fluence region. The removal of an outlier, Z=14, gives values of 0.888 and 0.705 for slope and R2 respectively. 相似文献
19.
M. I. Becka A. Jurewicz 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1996,17(12)
Currently conducted studies on modelling of scattered solar radiation in the 0.350-1.00 μm range along the Phobos orbit around Mars are presented. Our calculations include various types of grains, various densities and scattering angles. The calculations are performed with the aid of LOWTRAN7 program. These studies are directly related to the photometer coupled to PFS (Planetary Fourier Spectrometer) planned for the Mars-96 mission. 相似文献
20.
P.B. Marty S. Bardeau O. Czoske H. Ebeling J.P. Kneib R. Sadat I. Smail 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2004,34(12):2509-2515
We present an analysis of seven clusters observed by XMM-Newton as part of our survey of 17 most X-ray luminous clusters of galaxies at z 0.2 selected for a comprehensive and unbiased study of the mass distribution in massive clusters. Using the public software FTOOLS and XMMSAS we have set up an automated pipeline to reduce the EPIC MOS and pn spectro-imaging data, optimized for extended sources analysis. We also developped a code to perform intensive spectral and imaging analysis particularly focussing on proper background estimate and removal. XMM-Newton deep spectro-imaging of these clusters allowed us to fit a standard β-model to their gas emission profiles as well as a standard MEKAL emission model to their extracted spectra, and test their inferred characteristics against already calibrated relations. 相似文献