Let a finite semiorder, or unit interval order, be given. All its numerical representations (when suitably defined) form a convex polyhedron. We show that the facets of the representation polyhedron correspond to the noses and hollows of the semiorder. Our main result is to prove that the coordinates of the vertices and the components of the extreme rays of the polyhedron are all integral multi...

We present new a posteriori error estimates for the finite volume approximations of elliptic problems. They are obtained by applying functional a posteriori error estimates to natural extensions of the approximate solution and its flux computed by the finite volume method. The estimates give guaranteed upper bounds for the errors in terms of the primal (energy) norm, dual norm (for fluxes), and...

in present pet/ct scanners, pet attenuation correction is performed by relying on the information given by ct scan. in the ct-based attenuation correction methods, dual-energy technique (dect) is the most accurate approach, which has been limited due to the increasing patient dose. in this feasibility study, we have introduced a new method that can implement dual-energy technique with only a si...

Steel Plate Shear Wall (SPSW) is an emerging seismic load-resistant system that, compared to other systems, enjoys the advantages of stable ductile behavior, fewer detailing requirements, rapid constructability, and economy. American seismic provisions decree that a SPSW should be designed as a moment frame with a web infill plate. Specifically, in case of buildings taller than 160 ft, it decre...

The microstructure of dual phase steels can be considered as a matrix of ferrite phase reinforced by martensite particles. Recent measurements show that the mechanical properties of the ferrite phase are changed with the distance from the martensite grains. In this paper, a new method has been proposed to consider this phenomenon in finite element modeling of dual phase steels microstructure. I...

OBJECTIVE To analyze a nationally representative sample of women for correlates of dual-contraceptive-method use. MATERIALS AND METHODS We conducted an analysis of the National Survey of Family Growth, 2006-2008, a cross-sectional survey of reproductive-aged women in the United States. RESULTS Dual method use was reported by 7.3% of the 5,178 women in the sample. Correlates of higher rates ...

In this paper, we show that the moving directions of the primal-affine scaling method (with logarithmic barrier function), the dual-affine scaling method (with logarithmic barrier function), and the primal-dual interior point method are merely the Newton directions along three different algebraic "paths" that lead to a solution of the Karush-Kuhn-Tucker conditions of a given linear programming ...