In this article we study cocycles of discrete countable groups with values in 2G and the ring of affiliated operators UG. We clarify properties of the first cohomology of a group G with coefficients in 2G and answer several questions from De Cornulier et al. (Transform. Groups 13(1):125–147, 2008). Moreover, we obtain strong results about the existence of free subgroups and the subgroup structu...

Any line bundle L on a smooth curve C of genus g with degL ≥ 2g+1 is normally generated, i.e., φL(C) ⊆ PH(C,L) is projectively normal. However, it has known that more various line bundles of degree d failing to be normally generated appear on multiple coverings of genus g as d becomes smaller than 2g+1. Thus, investigating the normal generation of line bundles on multiple coverings can be an ef...

We model large angle intermediate energy pion-pion scattering by the pQCD two-gluon (2g) exchange contribution and discuss the onset of the dominance of the Glauber-Gribov-Landshoff (GGL) component. The pQCD 2g exchange contribution becomes substantial already at |t| ∼ 1 GeV, but the pQCD exchange dominance is deferred to |t| ∼ 3 GeV because of competing multiple soft rescattering effects. Base...

The goal of this note (which is incorporated and expanded in Chapter 5 of the author’s book “The large sieve and its applications” ) is to bound from above in a suitable manner the degree of irreducible representations, and the sum of the degrees of irreducible representations, of a group G`, which in applications is either between SL(r,F`) and GL(r,F`), or between Sp(2g,F`) and CSp(2g,F`). Mor...

This paper presents performance evaluation results for Internet access over the next generation of broadband wireless access networks (2G-BWA). The challenge for these, mostly fixed access technologies stems from non line-of-sight deployment with high coverage and spectrum efficiency combined with link performance comparable to that of competing wired technologies (DSL, Cable modem). We present...

Introduction k-t GRAPPA [1,2,3] has been proposed for dynamic imaging with high reduction factors. In this work, GRAPPA operator [4] and narrow window data sharing are used to significantly improve the accuracy and reconstruction speed of k-t GRAPPA. The enhanced version is called the second generation (2G) k-t GRAPPA. Experiments with cardiac cine data sets show that the 2G k-t GRAPPA can prod...

Current research focuses on the dynamics of mobile telecommunications market innovation from the perspectives of technology innovation or service adoption. However,because there is a mutual dependency between them, each perspective alone can only partly explain the pace and direction of change we currenly witness in this market. This research-in-progress combines them into one framework to purs...

A software defined radio (SDR) prototype based on a multiprocessor architecture (MPA) is developed. Software for Japanese personal handy phone system (PHS) of a 2G mobile system, and IEEE802.11 wireless LAN, which has much wider bandwidth than the 2G systems, is successfully implemented. Newly developed flexible-rate pre-/post-processor (FR-PPP) achieves the flexibility and wideband performance...

One of the most interesting 3G networks feature is their integration with the 2G networks. It provides seamless End to-End services. Current widely deployed 2G and 3G networks provide enabling interoperability. These mechanisms include Inter RAT idle mode reselection. Inter RAT dedicated mode reselection is used for PS (Packet Switching) services. The WLAN coverage on one hand provides an extra...