One of the most important factors in determining the depth of foundations in structures adjacent to the water flow is the scouring phenomenon; the scouring is a phenomenon caused by the interactions between water flow and erodible bed materials, which causes the removal of sediments where hydraulic structures are located, including bridge piers. Every year, a great number of bridges are damaged...

“rational choice model” is one of the economics theories which developed into sociology, politics, and anthropology and was applied to understand and justify some phenomena.  according to this hypothesis, the basis of decision making is improvements, enjoyment and suffering disposal. people always do all necessary calculations in each and every decision making and then adopt a rational decision...

An orthogonal system of rational functions is introduced. Some results on rational approximations based on various orthogonal projections and interpolations are established. These results form the mathematical foundation of the related spectral method and pseudospectral method for solving differential equations on the half line. The error estimates of the rational spectral method and rational p...

Economic voting is one of the most important mechanisms on explaining voting behavior and on establishing the democratic accountability. However, people tend to use perceived national economic condition on evaluating the incumbent, which is known as sociotropic voting, instead of their pocketbook. Previous studies suggest both altruism and self-interested future expectation may help explain thi...