Two new quasi-linear elliptic systems of partial differential equations to automatically generate twodimensional boundary conforming structured grids are formulated. One of the new systems generates grids with near-uniform cell areas. The other produces meshes with near-uniform coordinate line spacings. In both cases, the resulting grids conform to complex boundaries with severe singularities w...

Random number sequences are used in a wide range of applications such as simulation, sampling, numerical analysis, cryptography, and recreation. The quality of random number sequences is critical to the correctness of these applications. Many statistical tests have been developed to test various characteristics of random number generators such as randomness, independence, uniformity, etc. Most ...

Szemerédi’s Regularity Lemma proved to be a very powerful tool in extremal graph theory with a large number of applications. Chung [Regularity lemmas for hypergraphs and quasi-randomness, Random Structures and Algorithms 2 (1991), 241–252], Frankl and Rödl [The uniformity lemma for hypergraphs, Graphs and Combinatorics 8 (1992), 309–312, Extremal problems on set systems, Random Structures and A...

This research describes the goals, design and implementation of a quasi natural gradient, laboratory scale, sand tank (aquifer) model experiment. The model was used to study the transport of an inorganic tracer (Chloride) in groundwater, within a tropical aquifer (porous medium) material. Three-dimensional sand tank (1.8 m × 0.3 m × 0.8 m) experiments were conducted to investigate contaminant t...

In this paper, we consider a two-dimensional parabolic equation with two small parameters. These small parameters make the underlying problem containing multiple scales over the whole problem domain. By using the maximum principle with carefully chosen barrier functions, we obtain the pointwise derivative estimates of arbitrary order, from which an anisotropic mesh is constructed. This mesh use...

Continuing the study of the relationship between TC 0 , AC 0 and arithmetic circuits, started by Agrawal et al. 1], we answer a few questions left open in this paper. Our main result is that the classes DiiAC 0 and GapAC 0 coincide, under poly-time, log-space, and log-time uniformity. From that we can derive that under logspace uniformity, the following equalities hold:

due to the scarcity of water resources, the need for sustainable development of drip irrigation tape is essential in iran. a number of drip irrigation tape systems used in sugar beet fields of isfahan and chahar mahal va bakhtiari provinces were evaluated and were compared with furrow irrigation methods in two consecutive years. the actual water use efficiency (wuesy, wuewsy) in lower quarter, ...

We prove that PSL2(Z[ 1 p ]) gives the first example of groups which are not quasi-isometric to each other but have the same quasi-isometry group. Namely, PSL2(Z[ 1 p ]) and PSL2(Z[ 1 q ]) are not quasi-isometric unless p = q, and, independent of p, the quasi-isometry group of PSL2(Z[ 1 p ]) is PSL2(Q). In addition, we characterize PSL2(Z[ 1 p ]) uniquely among all finitely generated groups by ...

This paper revisits Williams (1997) on the effect of net rental price, asset quality and variable investment costs on the asset redevelopment decision. This paper develops a quasi-analytical method for solving the generalised real renovation option problem by treating the investment cost as having both a variable and a fixed element and then extends the analysis for the case where both the net ...