We prove that a manifold M is metrisable if and only if its group of homeomorphisms H (M) endowed with the compact-open topology is a qspace. We also discuss pseudo-character and tightness. All spaces under discussion are Tychonoff.

It is known that positive definiteness is not enough for the multidimensional moment problem to be solved. We would like throw in to the garden of existing in this matter so far results one more, a result which takes into considerations the utmost possible truncations. As we have already pointed out positive definiteness is not sufficient for a multisequence to be a moment one, neither in the c...

LetM be a closed, orientable, irreducible, geometrizable 3-manifold. We prove that the profinite topology on the fundamental group of π1(M) is efficient with respect to the JSJ decomposition of M . We go on to prove that π1(M) is good, in the sense of Serre, if all the pieces of the JSJ decomposition are. We also prove that if M is a graph manifold then π1(M) is conjugacy separable. A group G i...

We study the behavior of the eigenvalues of a sublaplacian ∆b on a compact strictly pseudoconvex CR manifold M, as functions on the set P+ of positively oriented contact forms on M by endowing P+ with a natural metric topology.

In this paper, a new circuit is proposed for step-up Z-source inverter based on QZSI (quasi-Z-source inverter). The proposed topology inherits all advantages of the conventional topology. The proposed topology in comparison with conventional topology reduces the ST (Shoot-through) duty cycle by over 25% at the same voltage boost factor. Theoretical analysis of the proposed qZSI in the ST and no...

In this paper, a new topology for cascaded multilevel inverter based on quasi-Z-source converter is proposed. In the proposed topology the magnitude of output DC voltage is not limited to the sum of magnitude of DC voltage sources. Moreover, the reliability of the circuit due to capability of short circuit by Z-source network is increased. The quasi-Z- source converter in different modes is ana...

Due to the favorable performance of structural topology optimization to create a proper understanding in the early stages of design, this issue is taken into consideration from the standpoint of research or industrial application in recent decades. Over the last three decades, several methods have been proposed for topology optimization. One of the methods that has been effectively used in stru...

In this paper a new topology for Dynamic Voltage Restorer (DVR) with high frequency link is proposed. This topology is able to compensate different types of voltage disturbances such as voltage sag, voltage swell and voltage harmonics. According to the obtained equations, this topology operates as a controllable current source to charge the series capacitor. Due to using High Frequency Transfor...

In this paper‎, ‎we introduce a new model of point free topology‎ ‎for point-set topology‎. ‎We study the basic concepts in this‎ ‎structure and will find that it is naturally close to point-set‎ ‎topology‎.‎

In this paper, a pointwise pseudo-metric function on the L-realline is constructed. It is proved that the topology induced by this pointwisepseudo-metric is the usual topology.