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61.
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
62.
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
63.
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
64.
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
65.
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
66.
The destination-choice and travel behaviour of urban Arab-Israelis from Haifa, and rural Arab-Israelis from the village of Ibillin, are compared. The study examines the role of tradition, socio-economic background and geographical location of residence, in designing the two communities' destination-choice and travel behaviour. The results show that while socio-economic characteristics and life in a city or in a village do not differentiate between the two communities, religious affiliation does play a major role in determining the destination-choice and tourist behaviour of the two sub-communities. It was also found that the predominant factors that shape Arab-Israelis' tourist behaviour are the familiarity factors and that social rather than personal constraints play a major role in deciding which tourist destination is chosen. Policy oriented conclusions are presented in the light of these findings. 相似文献
67.
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
68.
In this paper, a pan-sharpening method, using non-subsampled contourlet transform (NSCT) and the theory of compressive sensing (CS), is proposed. The NSCT is used for sparse image representation to perform a multiscale and directional decomposition of source images in order to express their detail and express the sparsity of their high frequency. The CS is used to merge the multispectral (MS) and panchromatic (pan) images from partial random measurements. Two different fusion rules are then applied. The final pan-sharpened image is obtained by inverse NSCT. Experimental results show the efficiency of the proposed method, compared with pan sharpening based on standard NSCT, in terms of visual quality and objective assessment. Moreover, the proposed technique is very effective when the storage and transmission bandwidth are limited. 相似文献
69.
70.
A combination of major and trace elements have been used to characterize surface- and groundwater in El Minia district, Egypt. Surface water versus groundwater chemistry data enabled geographical zonation and chemical types to be differentiated. The main target of this research is to investigate the groundwater quality and hydrochemical evaluation. The situation is further complicated by contamination with lithogenic and anthropogenic (agricultural and sewage wastewaters) sources and low plan exploitation techniques. The investigated Pleistocene aquifer is composed of sand and gravel of different sizes, with some clay intercalation. The semi-confined condition was around the River Nile shifted to unconfine outside the floodplain. The groundwater flow generally from south to north and locally diverts towards the western part from the River Nile. Fifty-six, 11, five, and two water samples were collected from the Pleistocene aquifer, River Nile, Ibrahimia canal, and Al Moheet drain, respectively. The collected water samples were analyzed for major and trace elements. The toxic metal concentrations of Al Moheet drain are higher than those in the River Nile and the Ibrahimia canal. Cr, Hg, As, and Cd concentrations in the River Nile and Ibrahimia canal are fluctuated above and below the WHO drinking standards. Se concentration in River Nile and Ibrahimia canal is below WHO drinking and irrigation guidelines. Total dissolved solid content in groundwater is generally low, but it is increased due to the western part of the study area. The geographic position of the River Nile, Ibrahimia canal, and Al Moheet drain impact on the groundwater quality. The PHREEQC confirm the high mixing proportions from the River Nile into the groundwater and decline away from it. In addition to the thicknesses of the Pleistocene, aquifer and aquitard layer enhance the River Nile and agricultural wastewaters intrusion into the aquifer system. The toxic metal concentrations (Pb, Cd, Cr, PO4, Se, Mn, As, Hg, Ni, Al, Fe, and SIO2) in groundwater were increased mainly in the northwestern and southeastern part (far from the River Nile). It is attributed to anthropogenic, high vulnerability rate (unconfined), and partially to lithogenic. In most localities, the groundwater are unsuitable for drinking and irrigation purposes with respect to Se concentration, while they are unsuitable for dinking according Mn, As, and Hg contents. There are some Cd and Pb anomalies concentrations, which cause severe restriction if used in irrigation. The results suggested that significant changes are urgently needed in water use strategy to achieve sustainable development. 相似文献