The Chinese ancient accounts of timing observations of 48 lunar eclipses and the secular variation of the Earth's spin speed are discussed. A series of T expressing the secular deceleration of the Earth's rotation was obtained. The average increase rate of length of the day is about 1.5 milliseconds per century.

It is found that a previously thought-to-be well established result of density wave theory, that there is no interaction between a quasistationary spiral density wave and the basic state (i.e. the axisymmetric part) of the galactic disk, is in fact false. When solved as a nonlinear and globally self-consistent problem, the presence of non-axisymmetric patterns such as spirals or bars is shown t...

In this paper it is explained how most of asteroids can avoid very close approach to Jupiter, to the earth for earth orbit crossing asteroids, and to Neptune for Kuiper-belt asteroids by mechanisms which work also for Neptune-Pluto system. In fact the mutual distance of the planets cannot become very small as the critical argument librates around 180 0 because of 2:3 mean motion resonance and t...

This paper provides a review of the recent literature on some aspects of secular trends in Western countries. In particular, we discuss height variation, mainly on the basis of conscript data. There are still large height differences between European countries, and there is a marked trend for the tallest conscripts to be in northern Europe and the shortest ones in the southern part of the conti...

the first aim of this article is to present zahed’s conceptual–operational model of freedom on the basis of islamic thoughts.  the second goal is to distinguish how freedom would run in the islamic society according to this operational model. finally, we will talk about the differences between this new conceptualization of freedom and the secular one. we will introduce theoretical, social and c...