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831.
The design schemes of cooling for the nozzle blades of high-temperature gas turbines are considered. The results of the thermal and hydraulic tests for the cooling systems of the nozzle vanes are presented. The prospective cooling system of the nozzle vanes of low and high pressure turbines is developed and presented. The test results for the vane with proposed design are presented. 相似文献
832.
Joaquín ABELLAN 《中国航空学报》2018,31(3):529-533
Two types of uncertainty co-exist in the theory of evidence: discord and non-specificity. From 90s, many mathematical expressions have arisen to quantify these two parts in an evidence. An important aspect of each measure presented is the verification of a coherent set of properties. About non-specificity, so far only one measure verifies an important set of those properties. Very recently, a new measure of non-specificity based on belief intervals has been presented as an alternative measure that quantifies a similar set of properties (Yang et al., 2016). It is shown that the new measure really does not verify two of those important properties. Some errors have been found in their corresponding proofs in the original publication. 相似文献
833.
The algorithms for achieving a practical increase in the rate of data transmission on the space-craft–ground tracking station line has been considered. This increase is achieved by applying spectral-effective modulation techniques, the technology of orthogonal frequency compression of signals using millimeterrange radio waves. The advantages and disadvantages of each of three algorithms have been revealed. A significant advantage of data transmission in the millimeter range has been indicated. 相似文献
834.
R. J. Lillis D. A. Brain S. W. Bougher F. Leblanc J. G. Luhmann B. M. Jakosky R. Modolo J. Fox J. Deighan X. Fang Y. C. Wang Y. Lee C. Dong Y. Ma T. Cravens L. Andersson S. M. Curry N. Schneider M. Combi I. Stewart J. Clarke J. Grebowsky D. L. Mitchell R. Yelle A. F. Nagy D. Baker R. P. Lin 《Space Science Reviews》2015,196(1-4):357-358
835.
N. E. Zubov E. A. Mikrin V. N. Ryabchenko A. V. Fomichev 《Russian Aeronautics (Iz VUZ)》2017,60(1):64-73
The problem of lateral motion stabilization is analytically solved for the fourth-order model of aircraft motion using the method of output signal control synthesis that is based on the control object decomposition. Numerical simulation data are presented. 相似文献
836.
837.
R.D. Bentley A. Csillaghy J. Aboudarham C. Jacquey M.A. Hapgood K. Bocchialini M. Messerotti J. Brooke P. Gallagher P. Fox N. Hurlburt D.A. Roberts L. Sanchez Duarte 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
Heliophysics is a new research field that explores the Sun–Solar System Connection; it requires the joint exploitation of solar, heliospheric, magnetospheric and ionospheric observations. 相似文献
838.
H. Fuke N. Izutsu D. Akita I. Iijima Y. Kato J. Kawada K. Matsushima Y. Matsuzaka E. Mizuta M. Namiki N. Nonaka S. Ohta Y. Saito T. Sato M. Seo Y. Shoji A. Takada K. Tamura M. Toriumi K. Yamada T. Yamagami T. Yoshida 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
The super-pressure balloon (SPB) has been expected to be a flight vehicle that can provide a long flight duration to science. Since 1997, we have developed the SPB. Now we are at the phase of developing an SPB of a practical size. In 2009, we carried out a test flight of a pumpkin-shaped SPB with a 60,000 m3 volume. The undesirable result of this flight aroused us to resolve the deployment instability of the pumpkin-shaped SPB, which has been known as one of the most challenging issues confronting SPB development. To explore this deployment issue, in 2010, we carried out a series of ground tests. From results of these tests, we found that an SPB design modified from pumpkin, named “tawara”, can be a good candidate to greatly improve the deployment stability of the lobed SPB. 相似文献
839.
N. Castelló-Mor X. Barcons L. Ballo 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
We explore the capabilities of the future space science mission IXO (International X-ray Observatory) for obtaining cosmological redshifts of distant Active Galactic Nuclei (AGNs) using the X-ray data only. We first find in which regions of the X-ray luminosity (LX) versus redshift (z) plane the weak but ubiquitous Fe Kα narrow emission line can deliver an accurate redshift (δz < 5%) as a function of exposure time, using a CCD-based Wide Field Imager (IXO/WFI) as the one baselined for IXO. Down to a 2–10 keV X-ray flux of 10−14 erg cm−2 s−1 IXO/WFI exposures of 100 ks, 300 ks and 1 Ms will deliver 20%, 40% and 60% of the redshifts. This means that in a typical 18′ × 18′ IXO/WFI field of view, 4, 10 and 25 redshifts will be obtained for free from the X-ray data alone, spanning a wide range up to z ∼ 2–3 and fairly sampling the real distribution. Measuring redshifts of fainter sources will indeed need spectroscopy at other wavebands. 相似文献
840.
Microorganisms have been found to etch volcanic glass within volcaniclastic deposits from the Ontong Java Plateau, creating micron-sized tunnels and pits. The fossil record of such bioalteration textures is interpreted to extend back ~3.5 billion years to include meta-volcanic glass from ophiolites and Precambrian greenstone belts. Bioalteration features within glass clasts from Leg 192 of the Ocean Drilling Program were investigated through optical microscopy and Fourier transform infrared (FTIR) spectroscopy of petrographic thin sections. Extended depth of focus optical microscopic imaging was used to identify bioalteration tubules within the samples and later combined with FTIR spectroscopy to study the organic molecules present within tubule clusters. The tubule-rich areas are characterized by absorption bands indicative of aliphatic hydrocarbons, amides, esters, and carboxylic groups. FTIR analysis of the tubule-free areas in the cores of glass clasts indicated that they were free of organics. This study further constrains the nature of the carbon compounds preserved within the tubules and supports previous studies that suggest the tubules formed through microbial activity. 相似文献