in recent years, it has become increasingly important to incorporate explicit dynamics in economic analysis. these two tools that mathematicians have developed, differential equations and optimal control theory, are probably the most basic for economists to analyze dynamic problems. in this paper i will consider the linear differential equations on the plane (phase diagram) and elements of nonl...

the present article studies the reality of “zohdyyat” by abul atahie. has abul atahie been a real pious? or has he chosen piety as a technic for poetry? is his piety islamic? or is it spiritual? or is he an infidel? the present article tries to study the doubts and accusations in this regard so that we will know the reality of his “zohdyyat”. for the sake of this reason we first study the eleme...

In the design process, architects tend to choose and arrange together primitive geometrical elements according to their own cognitive environment (as reflected by culture and education), taking into account as well the broader social environment from which planning requests emerge. Therefore, each of such elements plays a very specific role in the global system, resulting from a strong intentio...

The partial real line is an extension of the Euclidean real line with partial real numbers, which has been used to model exact real number computation in the programming language Real PCF. We introduce induction principles and recursion schemes for the partial unit interval, which allow us to verify that Real PCF programs meet their specification. They resemble the so-called Peano axioms for na...

Let R be a real closed field. An integer part for R is a subring that sits inside R the way the integers sit inside the reals. Mourgues and Ressayre [10] showed that every real closed field has an integer part. We may associate with R a value group G that is a subgroup of (R+, ·), a residue field k that is a subfield of R, and an integer part I. The Mourgues and Ressayre construction involves m...

In regard to the linear subspace T (n) of n n symmetric Toeplitz matrices over the real eld, the collection S(n) of all real and orthogonal matrices Q such that QTQT 2 T (n) whenever T 2 T (n) forms a group, called the stability group of T (n). This paper shows that S(n) is nite. In fact, S(n) has exactly eight elements regardless of the dimension n. Group elements in S(n) are completely charac...

A new method for schema analysis is described in which reasoning is based upon the real–world semantics of schema elements. The method distinguishes between intrinsic and in–context semantics, which respectively provide a basis for shallow and deep semantic comparisons between element. Real–world semantics are represent as element interpretations which map elements into a pre–defined common con...

this paper investigates the effect of exchange rate uncertainty on the iran’s import trade. the exchange rate ‎uncertainty series were generated utilizing the tarch model. this model analyzes the asymmetric effects. the analysis of uncertainty and asymmetry ‎of the exchange rate shows significant tarch ‎effect on iran’s exchange rates‎. the findings of the study indicate negative shocks (bad ne...

Identifying the top-k most frequent elements is one of the many problems associated with data streams analysis. It is a well-known and difficult problem, especially if the analysis is to be performed and maintained up to date in near real time. Analyzing data streams in time sliding window model is of particular interest as only the most recent, more relevant events are considered. Approximate ...