Raies nébulaires et coronales dans le spectre infrarouge de la Nova Delphini     

Yvette Andrillat  Léo Houziaux 《Astrophysics and Space Science》1970,6(1):36-44

Nova Delphini 1967 has been observed in the red and photographic infrared at the Haute-Provence Observatory from September 7 to November 12, 1968. Dispersions range from 230 Å/mm to 4 Å/mm. The slope of the continuous spectrum in the region 1.3–1.7 ^–1 leads to a gradient of 3.06, which did not appear to vary during the observing period. This gradient is, however, very different from the value 1.71 measured on plates secured in August 1968. Lines ofHi, Hei, Heii, Feii,Oi,Cii and forbidden transitions due toOi,Oii, Fevii, Fex, Fexi,Siii,Aiii,Av,Axi and Nixv have been identified. Their intensities at various dates are given in Table II. Line profiles could be measured for a few lines taken on a 39 Å/mm spectrogram on October 3. Hei 6678 and 7065 are displayed on Figures 2 and 3. Figure 4 gives the [Oii] doublet at 7319–7330, while the H profile, obtained on October 4 can be seen on Figure 5. The line extends over more than 45 Å and narrow absorptions are seen at 6551.05; 6555.75; 6563.15; 6571.49; 6574.45. Due to the absence of published data on radial velocities of absorption lines in the visible spectrum at that time, it is not possible to give a clear identification for these features. Some of them may belong to H, while others are probably due to metals.  相似文献   

Surface deformation due to loading of a layered elastic half-space: a rapid numerical kernel based on a circular loading element   总被引：1，自引：0，他引：1  

E. Pan  M. Bevis  F. Han  H. Zhou  R. Zhu 《Geophysical Journal International》2007,171(1):11-24

  相似文献   

Effective Elastic Thickness of Southeast Part of Arctic Ocean—Eurasia Continent—Pacific Ocean Geoscience Transect     

YuanBingqiang  YvetteHPoudjomDjomani 《中国地质大学学报(英文版)》2002,13(1):20-25

The effective lithospheric elastic thickness of the continent is an important parameter for examination of the large-scale structure and analyses of the mechanism of isostatic compensation within the plate, and a parameter standing for the strength of the lithosphere.The Te values along Quanzhou-Heishui,the southeast section of the Arctic Ocean-Eurasian Continent-Pacific Ocean geoscience transect, are estimated by using the coherence technique developed by Forsyth.Studies of the feature of the coher-ence between gravity and topography suggest that at short wavelengths(6.6-100km)for each data box that is used to estimate Te,the plate is strong enough to support topographic loads and gravity and topog-raphy are uncorrelated.At long wavelengths where the plate is deflected by surface and subsurface loads are compensated by the flexure model.Sichuan land-stone with low heat-flow values has high Te values whereas in Ninghua,Datian,land-stone with high heat-flow values has low Te values,which reflects a correlation,low heat-flow values corresponding to high Te values and high heat-flow values corresponding to low Te values.Te values can be divided into two sections:northwest high section and southeast low sec-tion.There is roughly a positive correlation between crustal thickness and effective elastic thickness of the lithosphere.  相似文献   

Shoreline accretion and sand transport at groynes inside the Port of Richards Bay     

J.S. Schoonees  A.K. Theron  D. Bevis 《Coastal Engineering》2006,53(12):1045-1058

The south-western shoreline along the entrance channel inside the Port of Richards Bay has experienced continued erosion. Four groynes were constructed to stabilise the shoreline. Monitoring of shoreline evolution provided valuable data on the accretion adjacent to two of the groynes and on the sediment transport rates at these groynes. Tides, beach slopes, winds, wave climate, current regime, and sand grain sizes were documented. The one site is “moderately protected” from wave action while the other is “protected” according to the Wiegel [Wiegel, R. L. (1964). Oceanographical engineering. Prentice Hall, Inc., Englewood Cliffs, NJ.] classification. The shoreline accreted progressively at the two groynes at 0.065 m/day and 0.021 m/day respectively. The shorelines accreted right up to the most seaward extremity of the groynes. Equilibrium shorelines were reached within about 3.5 years to 4 years, which compare well with other sites around the world. The mean wave incidence angle is large and was found to be about 22°. The median sand grain sizes were 0.33 mm and 0.37 mm. The groynes acted as total traps, the beach surveys were extended to an adequate depth, and cross-shore sediment transport did not cause appreciable net sand losses into the entrance channel. The net longshore transport rate along the study area, which is north-westbound, is only slightly lower than the gross longshore transport. The actual net longshore transport rates are 18 000 m³/year and 4 600 m³/year respectively at the two groynes. A rocky area limits the availability of sand at one groyne. There is fair agreement between the predicted and measured longshore transport rates at the other groyne.  相似文献   

Structure of coronal holes from UV and radio observations     

Franca Chiuderi Drago  Yvette Avignon  Roger J. Thomas 《Solar physics》1977,51(1):143-158

The coronal hole observed on May 31, 1973 is studied using extreme ultraviolet and radio observations. The EUV line is the Fe xv at = 284 Å and the radio frequencies are 169 and 408 MHz. An unsuccessful attempt to deduce an homogeneous model of the hole from these observations, shows that EUV and radio observations are inconsistent if interpreted in such a frame and if the EUV line intensity measurements in the hole are reliable.Inhomogeneities are therefore required to account for both observations. An inhomogeneous model consisting of hot (T2×10⁶K) elements covering 10% of the hole surface surrounded by regions of colder gas (T8×10⁵K) is able to explain both observations.  相似文献   

Surface Deformation due to Loading of a Layered Elastic Half-space: Constructing the Solution for a General Polygonal Load     

Michael Bevis  Ernian Pan  Hao Zhou  Feng Han  Richard Zhu 《Acta Geophysica》2015,63(4):957-977

We describe an algorithm for rapidly computing the surface displacements induced by a general polygonal load on a layered, isotropic, elastic half-space. The arbitrary surface pressure field is discretized using a large number, n, of equally-sized circular loading elements. The problem is to compute the displacement at a large number, m, of points (or stations) distributed over the surface. The essence of our technique is to reorganize all but a computationally insignificant part of this calculation into an equivalent problem: compute the displacements due to a single circular loading element at a total of m n stations (where m n is the product m × n). We solve this “parallel” problem at high computational speed by utilizing the sparse evaluation and massive interpolation (SEMI) method. Because the product m n that arises in our parallel problem is normally very large, we take maximum possible advantage of the acceleration achieved by the SEMI algorithm.  相似文献   

Reference frame access under the effects of great earthquakes: a least squares collocation approach for non-secular post-seismic evolution     

D. D. Gómez  D. A. Piñón  R. Smalley  M. Bevis  S. R. Cimbaro  L. E. Lenzano  J. Barón 《Journal of Geodesy》2016,90(3):263-273

  相似文献   

Observations spectroscopiques de HD 50138     

Yvette Andrillat  Léo Houziaux 《Astrophysics and Space Science》1972,18(2):324-328

Observations of the Be star HD 50138 have been extended to the photographic infrared region up to 9500 Å. The main features noted in this wavelength range are strong lines of Oi (8446 Å), Hi (from P 9 to P 20), the Caii infrared triplet and the 8629 line attributed to Ni. The 7772 multiplet of Oi is shown to undergo important changes during the period of observations (1959–1971). Higher Balmer lines do not exhibit any emission component, but their profiles are variable and indicate the presence of satellite absorption, as already mentioned by some authors.Les observations ont été obtenues aux télescopes de 120 et 193 cm de l'observatoire de Haute-Provence (CNRS).  相似文献   

GEODESY AND DIGITAL CARTOGRAPHIC SURVEY IN FILDES PENINSULA,REY JORGE ISLAND,ANTARCTICA   总被引：1，自引：0，他引：1  

Jürgen Klotz 《地球空间信息科学学报》2001,4(2):25-31

1　ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅｉｎｃｒｅａｓｅｉｎｒｅｓｅａｒｃｈｉｎｔｈｅＣｈｉｌｅａｎＡｎｔａｒｃｔｉｃＴｅｒｒｉｔｏｒｙｈａｓｂｅｃｏｍｅｍａｎｉｆｅｓｔｏｖｅｒｔｈｅｌａｓｔｔｅｎｙｅａｒｓｉｎｔｈｅｓｕｂｓｔａｎｔｉａｌｉｎｃｒｅａｓｅｉｎｔｈｅｎｕｍｂｅｒｏｆｓｃｉｅｎｔｉｆｉｃｓｔａｔｉｏｎｓｅｓｔａｂｌｉｓｈｅｄａｎｄｍａｉｎｔａｉｎｅｄｏｎＲｅｙＪｏｒｇｅＩｓｌａｎｄ ,ｍａｋｉｎｇｉｔｎｅｃｃｅｓａｒｙｔｏｒｅｇｕｌａｔｅｔｈｅｕｓｅｏｆｔｈｏｓｅａｒｅａｓｏｆｉｎｔｅｒｅ…  相似文献   

Phase changes and thermal subsidence in intracontinental sedimentary basins     

Yvette Hamdani  Jean-Claude Mareschal  Jafar Arkani-Hamed 《Geophysical Journal International》1991,106(3):657-665

  相似文献