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11.
This paper presents a comprehensive review of uncertainties involved in flight vehicle structural damage monitoring, diagnosis, prognosis and control. Uncertainties can cause infeasibilities, false diagnosis and very imprecise prognosis if not correctly taken into account. The purpose of this paper is to review existing methods that have been developed to address the problem of uncertainty in the area of damage sensing, diagnosis, prognosis and control in flight vehicles. The mathematical and statistical methods in analyzing uncertainty are first presented and compared. Then, the different sources and perspectives of uncertainties in the damage assessment process are presented and classified. Following this, diagnosis and prognosis methods are reviewed. Final review section covers the control of damaged structure under uncertainty. In each section and in the concluding remarks section the research challenges in the field of flight vehicle structural damage sensing, diagnosis and prognosis methods as well as control under uncertainty are identified and promising new ideas are discussed. 相似文献
12.
Niemann H.B. Atreya S.K. Bauer S.J. Biemann K. Block B. Carignan G.R. Donahue T.M. Frost R.L. Gautier D. Haberman J.A. Harpold D. Hunten D.M. Israel G. Lunine J.I. Mauersberger K. Owen T.C. Raulin F. Richards J.E. Way S.H. 《Space Science Reviews》2002,104(1-4):553-591
The Gas Chromatograph Mass Spectrometer (GCMS) on the Huygens Probe will measure the chemical composition of Titan's atmosphere
from 170 km altitude (∼1 hPa) to the surface (∼1500 hPa) and determine the isotope ratios of the major gaseous constituents.
The GCMS will also analyze gas samples from the Aerosol Collector Pyrolyser (ACP) and may be able to investigate the composition
(including isotope ratios) of several candidate surface materials.
The GCMS is a quadrupole mass filter with a secondary electron multiplier detection system and a gas sampling system providing
continuous direct atmospheric composition measurements and batch sampling through three gas chromatographic (GC) columns.
The mass spectrometer employs five ion sources sequentially feeding the mass analyzer. Three ion sources serve as detectors
for the GC columns and two are dedicated to direct atmosphere sampling and ACP gas sampling respectively. The instrument is
also equipped with a chemical scrubber cell for noble gas analysis and a sample enrichment cell for selective measurement
of high boiling point carbon containing constituents. The mass range is 2 to 141 Dalton and the nominal detection threshold
is at a mixing ratio of 10− 8. The data rate available from the Probe system is 885 bit/s. The weight of the instrument is 17.3 kg and the energy required
for warm up and 150 minutes of operation is 110 Watt-hours.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
13.
C Rodier O Vandenabeele-Trambouze R Sternberg D Coscia P Coll C Szopa F Raulin C Vidal-Madjar M Cabane G Israel M F Grenier-Loustalot M Dobrijevic D Despois 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2001,27(2):195-199
If there is, or ever was, life in our solar system beyond the Earth, Mars is the most likely place to search for. Future space missions will have then to take into account the detection of prebiotic molecules or molecules of biological significance such as amino acids. Techniques of analysis used for returned samples have to be very sensitive and avoid any chemical or biological contamination whereas in situ techniques have to be automated, fast and low energy consuming. Several possible methods could be used for in situ amino acid analyses on Mars, but gas chromatography would likely be the most suitable. Returned samples could be analyzed by any method in routine laboratory use such as gas chromatography, already successfully performed for analyses of organic matter including amino acids from martian meteorites. The derivatization step, which volatilizes amino acids to perform both in situ and laboratory analysis by gas chromatography, is discussed here. 相似文献
14.
M. E. Wiedenbeck W. R. Binns A. C. Cummings A. J. Davis G. A. de Nolfo M. H. Israel R. A. Leske R. A. Mewaldt E. C. Stone T. T. von Rosenvinge 《Space Science Reviews》2007,130(1-4):415-429
The galactic cosmic rays arriving near Earth, which include both stable and long-lived nuclides from throughout the periodic
table, consist of a mix of stellar nucleosynthesis products accelerated by shocks in the interstellar medium (ISM) and fragmentation
products made by high-energy collisions during propagation through the ISM. Through the study of the composition and spectra
of a variety of elements and isotopes in this diverse sample, models have been developed for the origin, acceleration, and
transport of galactic cosmic rays. We present an overview of the current understanding of these topics emphasizing the insights
that have been gained through investigations in the charge and energy ranges Z≲30 and E/M≲1 GeV/nuc, and particularly those using data obtained from the Cosmic Ray Isotope Spectrometer on NASA’s Advanced Composition
Explorer mission. 相似文献
15.
Fred Goesmann Helmut Rosenbauer Reinhard Roll Cyril Szopa Francois Raulin Robert Sternberg Guy Israel Uwe Meierhenrich Wolfram Thiemann Guillermo Munoz-Caro 《Space Science Reviews》2007,128(1-4):257-280
Comets are thought to preserve the most pristine material currently present in the solar system, as they are formed by agglomeration
of dust particles in the solar nebula, far from the Sun, and their interiors have remained cold. By approaching the Sun, volatile
components and dust particles are released forming the cometary coma. During the phase of Heavy Bombardment, 3.8--4 billion
years ago, cometary matter was delivered to the Early Earth. Precise knowledge on the physico-chemical composition of comets
is crucial to understand the formation of the Solar System, the evolution of Earth and particularly the starting conditions
for the origin of life on Earth. Here, we report on the COSAC instrument, part of the ESA cometary mission Rosetta, which
is designed to characterize, identify, and quantify volatile cometary compounds, including larger organic molecules, by in
situ measurements of surface and subsurface cometary samples. The technical concept of a multi-column enantio-selective gas
chromatograph (GC) coupled to a linear reflectron time-of-flight mass-spectrometer instrument is presented together with its
realisation under the scientific guidance of the Max-Planck-Institute for Solar System Research in Katlenburg-Lindau, Germany.
The instrument's technical data are given; first measurements making use of standard samples are presented. The cometary science
community is looking forward to receive fascinating data from COSAC cometary in situ measurements in 2014. 相似文献