Starting from the classical r-matrix of the non-standard (or Jordanian) quantum deformation of the sl(2,R) algebra, new triangular quantum deformations for the real Lie algebras so(2, 2), so(3, 1) and iso(2, 1) are simultaneously constructed by using a graded contraction scheme; these are realized as deformations of conformal algebras of (1 + 1)-dimensional spacetimes. Timetype and space-type q...

We present a 1-parameter family of finite action solutions to the S0(2, 1) Hitchin’s equations and explore some of its basic properties. For a fixed value of the parameter, the solution is smooth. We conclude by showing a multi-particle generalization of our basic solutions.

H abitat change and invasions of alien species are usually listed as the two biggest causes of biodiversity loss. When the two coincide, the results can be devastating, because altered habitat often favors alien species adapted to the changed conditions. This is particularly true in streams and rivers of North America, where homogenization of fish faunas through extinction of native species and...

due to the lack of information on most stations and economic constraints for collecting observed data. identification of a suitable hydrological model can help in the management of water resources. the ihacres model doesn't require complex data for input, so this model is superior to other models. in this research the efficiency of ihacres model for simulation of daily flow for polrood and...

RVR Meander was developed as a toolbox for modeling restoration and naturalization processes in rivers. This model includes Windows-based and Geographical Information System-based programs for analyzing and modeling planform migration of streams. In the past, several rivers have been channelized causing environmental and ecological problems. Restoration techniques evolve as natural solutions to...

Sediment transfer from continents to oceans via rivers is one of the important processes regulating river-bank stabilization, soil formation, biogeochemical cycling of elements, crust evolution and many other earth-related processes. Due to changes in continental positions during the geologic past, water flow and sediment loads in rivers have also shown variations during different time periods....

in this article, by using chebyshev’s polynomials and chebyshev’s expansion, we obtain the best uniform polynomial approximation out of p2n to a class of rational functions of the form (ax2+c)-1 on any non symmetric interval [d,e]. using the obtained approximation, we provide the best uniform polynomial approximation to a class of rational functions of the form (ax2+bx+c)-1 for both cases b2-4a...

The potential beneets of a uniform version of interpolation are hindered by its absence from many expressive logics. This motivates a thorough investigation of appropriate expansions of known entailments so that an easy-to-derive, uniform presentation of the interpolants is supported. This paper presents the skeleton of a general construction and indicates that a potentially large class of enta...

1. We examined the influence of hydrologic seasonality on temporal variation of planktonic bacterial production (BP) in relatively undisturbed lowland rivers of the middle Orinoco basin, Venezuela. We sampled two clearwater and two blackwater rivers over 2 years for dissolved organic carbon (DOC), chlorophyll, phosphorus and bacterial abundance to determine their relationship to temporal variat...

Preface The Healthy Rivers Commission has completed investigations of the coastal catchments of rivers and lakes as referred to it by the NSW Government since 1995. Lessons learnt from those Inquiries have led the Commission to establish a number of key principles and strategies, which it believes are essential to achieving healthy rivers, lakes and catchments. This document advances a vision f...