We extend the concept of manifold with boundary to weight and boundary weight functions. With the new concept, we obtained the double reciprocity laws for simplicial complexes, cubical complexes, and lattice polyhedra with weight functions. For a polyhedral manifold with boundary, if the weight function has the constant value 1, then the boundary weight function has the constant value 1 on the ...

Convex analysis” is developed for functions defined on integer lattice points. We investigate the class of functions which enjoy a variant of Steinitz’s exchange property. It includes linear functions on matroids, valuations on matroids (in the sense of Dress and Wenzel), and separable concave functions on the integral base polytope of submodular systems. It is shown that a function ω has the S...

Bluetooth enables portable electronic devices to communicate wirelessly via short-range ad-hoc networks. Initially Bluetooth will be used as a replacement for point-to-(multi)point cables. However, in due course, there will be a need for forming multihop ad-hoc networks over Bluetooth, referred to as scatternets. This paper investigates the capacity assignment problem in Bluetooth scatternets. ...

We introduce a new method for efficiently learning permutations that exploits the technique of extended formulation from the combinatorial optimization community. This extended formulation technique encodes the hard-to-describe polytope of permutations as the projection of an easier to describe polytope in a higher dimensional space. Although the best special-purpose algorithm for permutations ...

We study the classical stable marriage and stable roommates problems using a polyhedral approach. We propose a new LP formulation for the stable roommates problem, which has a feasible solution if and only if the underlying roommates problem has a stable matching. Furthermore, for certain special weight functions on the edges, we construct a 2-approximation algorithm for the optimal stable room...

The classical polytope associated with the symmetric traveling salesman problem (STSP) is usually studied as embedded in the standard subtour elimination polytope. Several classes of facet defining inequalities of the STSP polytope are used in practical enumeration algorithms. In this paper we consider the basic objects called pedigrees which are in 1-1 correspondence with the tours. The convex...

Gorenstein Fano polytopes arising from finite partially ordered sets will be introduced. Then we study the problem which partially ordered sets yield smooth Fano polytopes. Introduction An integral (or lattice) polytope is a convex polytope all of whose vertices have integer coordinates. Let P ⊂ R be an integral convex polytope of dimension d. • We say that P is a Fano polytope if the origin of...

We investigate geometric and topological properties of $d$-majorization -- a generalization classical majorization to positive weight vectors $d \in \mathbb{R}^n$. In particular, we derive new, simplified characterization which allows us work out halfspace description the corresponding polytopes. That is, write set all are $d$-majorized by some given vector $y \mathbb{R}^n$ as an intersection f...

We introduce the following cycle selection problem which is motivated by an application to kidney exchange problems. Given a directed graph G=(V,A), subset of arcs B ⊆A forming union cycles. A related optimization problem, Maximum Weighted Cycle Selection can be defined as follows: given weight wi,j∈R for all (i,j)∈A, find maximizes w(B). prove that this strongly NP-hard. Next, we focus on sele...

In Ehrhart theory, the h∗-vector of a rational polytope often provides insights into properties of the polytope that may be otherwise obscured. As an example, the Birkhoff polytope, also known as the polytope of real doubly-stochastic matrices, has a unimodal h∗-vector, but when even small modifications are made to the polytope, the same property can be very difficult to prove. In this paper, w...