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101.
A method to calculate secular terms of the two parts of the planetary disturbing function— when it is expressed in terms of the true anomalies or the eccentric anomalies instead of the mean anomalies - is described. Also an alternative method is outlined.  相似文献   
102.
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   
103.
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   
104.
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   
105.
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   
106.
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   
107.
The determination of the compaction parameters such as optimum water content (wopt) and maximum dry unit weight (γdmax) requires great efforts by applying the compaction testing procedure which is also time consuming and needs significant amount of work. Therefore, it seems more reasonable to use the indirect methods for estimating the compaction parameters. In recent years, the artificial neural network (ANN) modelling has gained an increasing interest and is also acquiring more popularity in geotechnical engineering applications. This study deals with the estimation of the compaction parameters for fine‐grained soils based on compaction energy using ANN with the feed‐forward back‐propagation algorithm. In this study, the data including the results of the consistency tests, standard and modified Proctor tests, are collected from the literature and used in the analyses. The optimum structure of a network is determined for each ANN models. The analyses showed that the ANN models give quite reliable estimations in comparison with regression methods, thus they can be used as a reliable tool for the prediction of wopt and γdmax. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
108.
109.
The present study examined groundwater recharge/discharge mechanisms in the regional Central Sudan Rift Basins (CSRB). Aquifers in CSRB constitute poorly sorted silisiclastics of sand, clay and gravels deposited in closed hydrologic systems of the Cretaceous–Pleistocene fluviolacustrine environments. CSRB are bounded to the north by the highlands of the Central African Shear Zone (CAZS) that represents the surface and groundwater divides. Sporadic recharge in the peripheries of the basins along the CASZ occurs subsequent to decadal and centennial storm events. Inflow from the Nile into the aquifers represents an additional source of recharge. Thus, groundwater resources cannot be labelled fossil nor can they be readily recharged. Closed hydrologic troughs located adjacent to the influent Nile system mark areas of main groundwater discharge characterized by lower hydraulic heads. This study has examined mechanisms that derive the discharge of the groundwater in these closed basins and concluded that only evapotranspirative discharge can provide a plausible explanation. Groundwater abstraction is mainly through deep‐rooted trees and effective evaporation. The increase of TDS along the flow indicates local recharge at the peripheries of basins and shows the influence of evaporation and rock/water interaction. The decline in groundwater level along a flow path was calculated using Darcy's law to estimate average recharge and evapotranspirative discharge, which are equal under natural equilibrium and make the only fluxes in CSRB. Steady‐state 2D flow modelling has demonstrated that an average recharge of 4–8 mm yr?1 and evapotranspirative discharge of 1–22 mm yr?1 will maintain natural equilibrium in CSRB. Sporadic storms provide recharge in the highlands to preserve the current hydraulic gradient and maintain aquifer dynamics. Simulated recharge from the Nile totals about 17·5 mm yr?1 and is therefore a significant contributor to the water balance. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
110.
As laser–plasma interactions access ever-increasing ranges of plasma temperatures and densities, it is interesting to consider whether they will some day shed light on questions concerning nuclear synthesis. One such open question is the process of endothermic nuclear synthesis for elements with A > 60, thought to have taken place at a point in time during the big bang, or currently in supernovae. We present an explanation based on a Boltzmann equilibrium condition, in combination with the change of the Fermi-statistics from the relativistic branch for hadrons from higher than nuclear densities to the lower density subrelativistic branch. The Debye length confinement of nuclei breaks down at the relativistic change, thus leading to the impossibility of nucleation of the quark-gluon state at higher than nuclear densities. Taking the increment for the proton number Z as Z′ = 10 of the measured standard abundance distribution (SAD) of the elements for a Boltzmann probability for heavy element synthesis, a sequence 3 n was found with the exponent n for the sequence of the magic numbers. The jump between the magic numbers 20 and 28 does not need then the usual spin-orbit explanation.  相似文献   
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