Power grid vulnerability is a major concern of our society, and its protection problem is often formulated as a tri-level defender-attacker-defender model. However, this tri-level problem is computationally challenging. In this paper, we design and implement a Column-and-Constraint Generation algorithm to derive its optimal solutions. Numerical results on an IEEE system show that: (i) the devel...

Current DNA sequencing technologies do not read an entire chromosome from end to end but instead produce sets of short reads, i.e. fragments of the genome. Haplotype assembly is the problem of assigning each read to the correct chromosome in the set of chromosomes in a homologous group, with the aid of the reference sequence. In this paper, we extend an existing exact algorithm for haplotype as...

s and Program, Geological Society of America, Denver,Colo., 28(7,) A-261.Turcios, L. M., and Gray, J. R. (2001). „U.S. Geological Surveysediment and ancillary data on the World Wide Web.‰ Proceedings of the 7th Federal Interagency Sedimentation Conference, Subcommittee on Sedimentation, Reno, Nev.,Poster 31-36.Turcios, L. M., Gray, J. R., and Ledford, A. L. (2000). „...

Accurate salt interpretation involves an integration of geology and geophysics. In the practice of salt interpretation and model building in depth imaging, we see two problems that could happen: exclusive geophysical interpretation without geological input and insufficient geological interpretation without understanding how the geophysical data are processed and without evaluating the limit and...

We consider the problem of augmenting a graph with n vertices embedded in a metric space, by inserting one additional edge in order to minimize the diameter of the resulting graph. We present an exact algorithm for the cases when the input graph is a path that runs in O(n log n) time. We also present an algorithm that computes a (1 + ε)approximation in O(n+1/ε) time for paths in R, where d is a...

In the Intervalizing Colored Graphs problem, one must decide for a given graph G = (V,E) with a proper vertex coloring of G whether G is the subgraph of a properly colored interval graph. For the case that the number of colors k is xed, we give an exact algorithm that uses O∗(2n/log (n)) time for all > 0. We also give an O∗(2n) algorithm for the case that the number of colors k is not xed.

3D geological models become increasingly important and popular recently. But it is too difficult to share the models because of different models come from different modeling software. It is urgent to solve the problem for the unification of data management. Based on it, the paper explains basic construction and architecture if GeoSciML to discuss how to take advantage of this standard and defin...

numerous empirical correlations exist for the estimation of crude oil viscosities. most of these correlations are not based on the experimental and field data from iranian geological zone. in this study several well-known empirical correlations including beal, beggs, glasso, labedi, schmidt, alikhan and naseri were optimized and refitted with the iranian oil field data. the results showed that ...

Vast quantities of natural gas are held in hydrate form in geologic reservoirs in sub-oceanic sediments and arctic permafrost zones (KVENVOLDEN, 1988; SLOAN, 1998), where conditions of high pressure and low temperature are within the hydrate stability region. In 1995, the U.S. Geological Survey (USGS) conducted a study to assess the quantity of natural gas hydrate resources in the United States...