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111.
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
112.
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
113.
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
114.
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
115.
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
116.
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
117.
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
118.
Lake Seyfe is located in a closed basin near K?r?ehir in the central Anatolian region, Turkey. The aim of this study is to evaluate the groundwater quality and effects of lithogenic contamination carried out in the Lake Seyfe basin, which is represented by various lithologies and groundwater types. Seyfe, Horla and Akp?nar springs are recharged through marbles at the western and southwestern of the basin are ultimately and discharged into the K?z?l?rmak Formation and Lake Seyfe. The waters of deep wells drilled into the marbles are of bicarbonate type (type I) in the Ca2+–Mg2+–HCO3 ? and Ca2+–HCO3 ? facies. Özlühüyük spring and waters from most of trenches and shallow wells, which are fed by the K?z?l?rmak Formation, have a mixed (type II) composition in the Ca2+–Mg2+–HCO3 ?–Cl? facies. Groundwater in the alluvium and K?z?l?rmak Formation along Lake Seyfe has a salty (type III) character in the Na+–Cl? facies. The main reasons of formation and change of the groundwater salinity and hydrochemical facies in the Seyfe basin are causing the various (a) lithogenic pollution and heterogeneity of the K?z?l?rmak Formation, (b) salinity of the upper soil zones, and (c) evaporation of the trench and channel waters open to the atmosphere. Considering parameters such as sodium hazard, specific conductivity, bicarbonate and carbonate hazards, waters in the study area are generally suitable for agricultural usage. 相似文献
119.
An outline of a new method is given to obtain the expansion of –S
by the method of W. M. Smart, using Taylor theorem and neglecting powers higher than the fourth in the eccentricity and inclination. 相似文献
120.
The United Kingdom Institute of Hydrology (UKIH) smoothed minima baseflow separation method originally developed for the daily flow data of perennial streams and adopted for intermittent streams is presented. The adopted method (AdUKIH) is the generalized version of the UKIH and hence applicable not only to intermittent streams but also to perennial streams. The AdUKIH method is applied on three daily streamflow gauging stations from the European part of Turkey, the Thrace region. The AdUKIH enables one to change the parameter 0·9 in the UKIH method and also introduces different block sizes, which is limited to five days in the original UKIH method. The AdUKIH method is considered a useful tool in helping practitioners and researchers to separate continuous baseflow from the daily flow in perennial and intermittent streams. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献