Integer numbers of natural units （Planck units） to express Newton＇s inverse square law of gravitation in terms of quantum mechanical probabilities are used. The strong nuclear force between two coupled nucleons is ...Integer numbers of natural units （Planck units） to express Newton＇s inverse square law of gravitation in terms of quantum mechanical probabilities are used. The strong nuclear force between two coupled nucleons is derived, the minds of giants such as Newton and Einstein are met. There is a considerable continuing effort directed for the understanding of gravity and the constants of nature, last century＇s legacy of Arthur Stanley Eddington.展开更多
An efficient water use requires accurate estimations of crop ET （evapotranspiration）. However, an accurate ET estimation is really difficult to achieve when big regions such as irrigation districts or complete water...An efficient water use requires accurate estimations of crop ET （evapotranspiration）. However, an accurate ET estimation is really difficult to achieve when big regions such as irrigation districts or complete watersheds are involved. Satellite images are an alternative that can be used to estimate accurate crop ET for big regions. In the present study, two known methods were used to estimate crop ET, the METRIC model which was developed by the University of Idaho and a Kc-NDVI relationship. In the METRIC model, ET is estimated as a residual of the energy balance equation. The second method uses reference ET, and estimates a crop coefficient （K,.） as a linear function of the NDVI vegetation index. ET was estimated in a section of the Rio Mayo Irrigation District located in Sonora, Mexico using Landsat 7 satellite images. Crop ET of the main crops was estimated. Results show some differences between both methods. An average ET depth of 460 mm for the wheat average growing season was found when using METRIC, while an average ET depth of 421 mm was found when using the Kc-NDVI relationship. A water use total efficiency of 62% and 63% was found for METRIC and the Kc-NDVI relationship, respectively.展开更多
An improved nonlinear Schrodinger equation different from usual one of spinor Bose-Einstein condensates （BECs） in an optical lattice are obtained by taking into account a nonlinear term in the equation of motion for...An improved nonlinear Schrodinger equation different from usual one of spinor Bose-Einstein condensates （BECs） in an optical lattice are obtained by taking into account a nonlinear term in the equation of motion for probability amplitude of spins carefully. The elliptic function wave solutions of the model are found under specific boundary condition, for example, the two ends of the atomic chain are fixed. In the case of limit the elliptic function wave solutions are reduced into spin-wave-like or solitons.展开更多
The article presents the situation in Latvia ahead of the country＇s adoption of the euro by offering an analysis of the extent to which the country is prepared for the move and of general economic difficulties as wel...The article presents the situation in Latvia ahead of the country＇s adoption of the euro by offering an analysis of the extent to which the country is prepared for the move and of general economic difficulties as well as indicating possible threats to its future development. The article talks about difficulties caused by the great unemployment connected with the specific economy of the country, political problems of the post-socialistic multinational country and steps done towards the fulfilling of all the convergence criteria. Its aim is to present the moments around the change of the currency which is done by the material＇s analysis because there are not enough statistical data for the mathematical analysis. It can be concluded that the adoption of the euro will probably be beneficial in the long run for Latvia＇s economy. The conclusions may be done by comparison with the situation of Estonia and its foreign trade with Poland which is shown in the article because there are a lot of similarities between the two Baltic countries.展开更多
Accelerating vacua with maximally symmetric, but not necessarily spherical, sections for Einstein and Gauss-Bonnet gravities in generic dimensions are obtained. The acceleration parameter has the effect of shifting th...Accelerating vacua with maximally symmetric, but not necessarily spherical, sections for Einstein and Gauss-Bonnet gravities in generic dimensions are obtained. The acceleration parameter has the effect of shifting the cosmological constants in Einstein gravity, whereas in Gauss-Bonnet gravity the effective cosmological constants remain the same in the presence of acceleration as in the case without acceleration.展开更多
文摘Integer numbers of natural units （Planck units） to express Newton＇s inverse square law of gravitation in terms of quantum mechanical probabilities are used. The strong nuclear force between two coupled nucleons is derived, the minds of giants such as Newton and Einstein are met. There is a considerable continuing effort directed for the understanding of gravity and the constants of nature, last century＇s legacy of Arthur Stanley Eddington.
文摘An efficient water use requires accurate estimations of crop ET （evapotranspiration）. However, an accurate ET estimation is really difficult to achieve when big regions such as irrigation districts or complete watersheds are involved. Satellite images are an alternative that can be used to estimate accurate crop ET for big regions. In the present study, two known methods were used to estimate crop ET, the METRIC model which was developed by the University of Idaho and a Kc-NDVI relationship. In the METRIC model, ET is estimated as a residual of the energy balance equation. The second method uses reference ET, and estimates a crop coefficient （K,.） as a linear function of the NDVI vegetation index. ET was estimated in a section of the Rio Mayo Irrigation District located in Sonora, Mexico using Landsat 7 satellite images. Crop ET of the main crops was estimated. Results show some differences between both methods. An average ET depth of 460 mm for the wheat average growing season was found when using METRIC, while an average ET depth of 421 mm was found when using the Kc-NDVI relationship. A water use total efficiency of 62% and 63% was found for METRIC and the Kc-NDVI relationship, respectively.
基金supported by National Natural Science Foundation of China under Grant No.10474022
文摘An improved nonlinear Schrodinger equation different from usual one of spinor Bose-Einstein condensates （BECs） in an optical lattice are obtained by taking into account a nonlinear term in the equation of motion for probability amplitude of spins carefully. The elliptic function wave solutions of the model are found under specific boundary condition, for example, the two ends of the atomic chain are fixed. In the case of limit the elliptic function wave solutions are reduced into spin-wave-like or solitons.
文摘The article presents the situation in Latvia ahead of the country＇s adoption of the euro by offering an analysis of the extent to which the country is prepared for the move and of general economic difficulties as well as indicating possible threats to its future development. The article talks about difficulties caused by the great unemployment connected with the specific economy of the country, political problems of the post-socialistic multinational country and steps done towards the fulfilling of all the convergence criteria. Its aim is to present the moments around the change of the currency which is done by the material＇s analysis because there are not enough statistical data for the mathematical analysis. It can be concluded that the adoption of the euro will probably be beneficial in the long run for Latvia＇s economy. The conclusions may be done by comparison with the situation of Estonia and its foreign trade with Poland which is shown in the article because there are a lot of similarities between the two Baltic countries.
基金Supported by the National Natural Science Foundation of China (NSFC) under Grant No.10875059
文摘Accelerating vacua with maximally symmetric, but not necessarily spherical, sections for Einstein and Gauss-Bonnet gravities in generic dimensions are obtained. The acceleration parameter has the effect of shifting the cosmological constants in Einstein gravity, whereas in Gauss-Bonnet gravity the effective cosmological constants remain the same in the presence of acceleration as in the case without acceleration.
