In this paper we propose an indexing structure for bitemporal databases. Such structure is based on two trees, one indexing valid time and another indexing transaction time. The trees share pointers to the actual data records, which are thus not duplicated. Bitemporal queries are processed by dividing the query in two parts, a valid time part and a transaction time part. Each tree is searched a...

We wish to demonstrate here the following elementary inequality of the differential calculus. If a function satisfies the conditions {ƒ(*)} ^ 1 and {/(x)} 2 + {F-»(x)} ^ 1 for all x and for some positive integer n, then the latter inequality is valid also when n is replaced by any smaller positive integer. Tha t such an inequality might be true is suggested by the validity of a similar but more...

OBJECTIVE An imbalance in the distribution of economic resources, i.e., income inequality, is a characteristic of a community that may influence the aggregate health of the population. In North America, income inequality seems to be strongly related to mortality rates among American communities such as states and metropolitan areas but largely irrelevant for health at similar levels of geopolit...

We show that the validity of the non-commutative Khintchine inequality for some q with 1 < q < 2 implies its validity (with another constant) for all 1 ≤ p < q. We prove this for the inequality involving the Rademacher functions, but also for more general " lacunary " sequences, or even non-commutative analogues of the Rademacher functions. For instance, we may apply it to the " Z(2)-sequences ...

We investigate the algorithmic and implementation issues related to the eeective and eecient use of lifted cover inequalities and lifted GUB cover inequalities in a branch-and-cut algorithm for 0-1 integer programming. We have tried various strategies on several test problems and we identify the best ones for use in practice. Branch-and-cut, with lifted cover inequalities as cuts, has been used...

An Arguesian identity is an identity in Grassmann-Cayley algebras with certain multi-linear properties of expressions in joins and meets of vectors and covectors. Many classical theorems of projective geometry and their generalizations to higher dimensions can be expressed as simple and elegant Arguesian identities. In a previous work we showed that an Arguesian identity can be unfolded with re...

A cutting-plane procedure for integer programming (IP) problems usually involves invoking a blackbox procedure (such as the Gomory-Chvátal (GC) procedure) to compute a cutting-plane. In this paper, we describe an alternative paradigm of using the same cutting-plane black-box. This involves two steps. In the first step, we design an inequality cx ≤ d where c and d are integral, independent of th...

The problem considered in this paper is whether an inequality of ω-terms is valid in a given level of a concatenation hierarchy of star-free languages. The main result shows that this problem is decidable for all (integer and half) levels of the Straubing-Thérien hierarchy.

We develop a method for the analysis of mixed finite element methods for the Stokes problem in the velocity-pressure formulation. A technical "macroelement condition", which is sufficient for the classical Babuska-Brezzi inequality to be valid, is introduced. Using this condition,we are able to verify the stability, and optimal order of convergence, of several known mixed finite element methods.

This is an expository article. Some developments on refinements, generalizations, applications of Jordan’s inequality and related problems, including some estimates for three classes of complete elliptic integrals and several proofs of Wilker’s inequality, are summarized. 1. Refinements of Jordan’s inequality 1.1. Jordan’s inequality. The well-known Jordan’s inequality (see [2, 9], [5, p. 143],...