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111.
Osman Demircan 《Astrophysics and Space Science》1978,56(2):389-401
A new general expression for the theoretical momentsA
2m of the light curves of eclipsing systems has been presented in the form of infinite series expansion. In this expansion, the terms have been given as the product of two different polynomials which satisfy certain three-term recursion formulae, and the coefficients diminish rapidly with increasing number of terms. Thus, the numerical values of the theoretical momentsA
2m can be generated recursively up to four significant figures for any given set of eclipse elements. This can be utilized to solve the eclipse elements in two ways: (i) with an indirect method (for the procedures see Paper XIV, Kopal and Demircan, 1978), (ii) with a direct method as minimization to the observational momentsA
2m (area fitting). The procedures given in Paper XIV for obtaining the elements of any eclipsing system consisting of spherical stars have been automated by making use of the new expression for the momentsA
2m of the light curves. The theoretical functionsf
0,f
2,f
4,f
6,g
2 andg
4 which are the functions ofa andc
0, have been used to solve the eclipse elements from the observed photometric data. The closed-form expressions for the functionsf
2,f
4 andf
6 have also been derived (Section 3) in terms of Kopal'sI-integrals.The automated methods for obtaining the eclipse elements from one minimum alone have been tested on the light curves of YZ (21) Cassiopeiae under the spherical model assumptions. The results of these applications will be given in Section 5 which follows a brief introduction to the procedure we followed. 相似文献
112.
Osman M. Kamel 《Earth, Moon, and Planets》1996,74(1):1-6
We present a literal approach to evaluate –s
necessary for the construction of high order planetary theories. This approach is valid to be applied on very large scale digital computers with standard Poisson series programs, for high order and high degree planetary theories. We apply the method of symbolic differential operators for single variable functions, and the binomial theorem expansions, for the evaluation of –s
. We utilize Laplace coefficients and its derivatives to carry out the development, without dealing with Newcomb operators or Hansen's coefficients. 相似文献
113.
A solution of the Uranus-Neptune planetary canonical equations of motion through the Von Zeipel technique is presented. A unique determinging function which depends upon mixed canonical variables, reduces the 12 critical terms of the Hamiltonian to the set of its secular terms. The Poincaré canonical variables are used. We refer to a common fixed plane, and apply the Jacobi-Radau set of origins. In our expansion we neglected terms of power higher than the fourth with respect to the eccentricities and sines of the inclinations. 相似文献
114.
In this part we obtain the expression for –s
by the application of Smart's method, which involves Taylor's theorem for functions of several variables. We neglected terms of power higher than the fourth with respect to eccentricities and tangents of inclinations. 相似文献
115.
Osman M. Kamel 《Earth, Moon, and Planets》1982,27(4):407-415
An outline for the elimination of the critical terms of a first order Uranus-Neptune theory is presented with a stress on the application of Hori's procedure to the problem. 相似文献
116.
Osman M. Kamel 《Astrophysics and Space Science》1979,64(1):227-238
We construct a first-order secular general planetary theory, using the Jacobi-Radau set of origins, referring to common fixed plane and in terms of Poincaré canonical variables. We neglect powers higher than the fourth with respect to the eccentricities and sines of inclinations. 相似文献
117.
The UBV photometry of a detached F-type eclipsing binary V505 Persei is presented. The light curve solution by a simple spherical model combined with the radial velocity data from two high resolution spectra by Marschall et al. (1990) reveals that the system is formed with two identical component stars of M 1.2 M in the main sequence close to ZAMS in evolution. They should have about solar metallicity (z 0.017). The isochrones with solar metallicity by Van denBerg (1985) yield an age of about (2.2± 0.5) × 109 yr for the system. The distance of the system should be about 60 pc. 相似文献
118.
Davut?AydoganEmail author Ali?Elmas A.?Muhittin?Albora Osman?N.?Ucan 《Marine Geophysical Researches》2005,26(1):1-15
In this study, structural features in the Aegean Sea were investigated by application of Cellular Neural Network (CNN) and
Cross-Correlation methods to the gravity anomaly map. CNN is a stochastic image processing technique, which is based on template
optimization using neighbourhood relationships of pixels, and probabilistic properties of two-Dimensional (2-D) input data.
The performance of CNN can be evaluated by various interesting real applications in geophysics such as edge detection, data
enhancement and separation of regional/residual potential anomaly maps. In this study, CNN is used in edge detection of geological
bodies closer to the surface, which are masked by other structures with various depths and dimensions. CNN was first tested
for (prismatic) synthetic examples and satisfactory results were obtained. Subsequently, CNN/Cross-Correlation maps and bathymetric
features were evaluated together to obtain a new structural map for most of the Aegean Sea. In our structural map, the locations
of the faults and basins are generally in accordance with the previous maps from restricted areas based on seismic data. In
the southern and southeastern parts of the Aegean Sea, E–W trending faults cut NE–SW trending basins and faults, similar to
on-shore Western Anatolia. Also, in the western, central and northern parts of the Aegean Sea, all of these structures are
truncated by NE-trending faults. 相似文献
119.
The Bekten Fault is 20-km long N55°E trending and oblique-slip fault in the dextral strike-slip fault zone. The fault is extending sub-parallel between Yenice-Gönen and Sar?köy faults, which forms the southern branch of North Anatolian Fault Zone in Southern Marmara Region. Tectonomorphological structures indicative of the recent fault displacements such as elongated ridges and offset creeks observed along the fault. In this study, we investigated palaeoseismic activities of the Bekten Fault by trenching surveys, which were carried out over a topographic saddle. The trench exposed the fault and the trench stratigraphy revealed repeated earthquake surface rupture events which resulted in displacements of late Pleistocene and Holocene deposits. According to radiocarbon ages obtained from samples taken from the event horizons in the stratigraphy, it was determined that at least three earthquakes resulting in surface rupture generated from the Bekten Fault within last ~1300 years. Based on the palaeoseismological data, the Bekten Fault displays non-characteristic earthquake behaviour and has not produced any earthquake associated with surface rupture for about the last 400 years. Additionally, the data will provide information for the role of small fault segments play except for the major structures in strike-slip fault systems. 相似文献
120.
In order to investigate the seismicity of western Anatolia limited with the coordinates of 36°–40° N, 26°–32° E, Gutenberg–Richter magnitude–frequency relation, seismic risk and recurrence period have been computed. The data belonging to both the historical period before 1900 (I0 ≥ 5.0 corresponding to MS ≥ 4.4) and the instrumental period until the end of 2006 (MS ≥ 4.0) has been used in the analysis. The study area has been divided into 13 sub-regions due to certain seismotectonic characteristics, plate tectonic models and geology of the region. All the computations have been performed for these sub-regions, separately. According to the results, a and b values in the computed magnitude–frequency relations are in the intervals 3.19±0.17 – 5.15±0.52 and 0.42±0.05 – 0.66±0.07, respectively. The highest b values have been determined for sub-regions 3 and 12 (Demirci-Gediz and Gökova Gulf-Mu?la-Gölhisar). The lowest b values have also been determined for sub-regions 1 and 9 (Bal?kesir and Bodrum-?stanköy). Finally, seismic risk and recurrence period computations from a and b values have shown as expected that sub-regions 1 and 9 which have the lowest b values and the highest risks and the shortest-recurrence periods. 相似文献