We propose a syntax-semantics interface that realises the mapping between syntax and semantics as a relation and does not make functionality assumptions in either direction. This interface is stated in terms of Extensible Dependency Grammar (XDG), a grammar formalism we newly specify. XDG’s constraint-based parser supports the concurrent flow of information between any two levels of linguistic ...

We discuss the student scheduling problem as it generally applies to high-schools in North-America. We show that the problem is NP-hard and discuss various variations to its formulation. We focus on multi-commodity flow problems because there has recently been much work and a number of interesting results on approximates solutions to such problems.

The understanding of the performance and design of national networks with rerouting is now well ad­ vanced. In particular, simple and robust dynamic routing strategies, and sympathetic dimensioning procedures, have been developed. However, the extension of this understanding to international net­ works requires consideration of a number of new issues. An important example concerns the partition...

In this paper, we address optimal network coding schemes for two-user unicast networks. Using previous results on the relationship between graph structure and informationtheoretic capacity, we characterize the capacity region for a class of two-user unicast networks by finding a combination network coding/routing scheme to achieve an outer bound on capacity. This scheme has the remarkable prope...

We consider the problem of expanding arc capacities in a network subject to demand and travel time uncertainty. We propose a robust optimization approach to obtain capacity expansion solutions that are insensitive to this uncertainty. Our results show that, under reasonable assumptions for network flow applications, such robust solutions can be computed by solving tractable conic linear problem...

We introduce a model for the computation of a multicommodity flow together with back-up flows for each commodity after any of a given set of failure states occurs in a network. We call such a total routing strategy a restorable multicommodity flow. One advantage of restorable flows over classical network protection methods, such as disjoint paths, is that the commodities may effectively share c...

the existing works considering the flow-based discount factor in the hub and spoke problems, assume that increasing the amount of flow passing through each edge of network continuously decreases the unit flow transportation cost. although a higher volume of flow allows for using wider links and consequently cheaper transportation, but the unit of flow enjoys more discounts, quite like replacing...

We consider the routing problem in wireline, packet-switched communication networks. We cast our optimal routing problem in a multicommodity network flow optimization framework. Our cost function is related to the congestion in the network, and is a function of the flows on the links of the network. The optimization is over the set of flows in the links corresponding to the various destinations...

A method for establishing electronic traceability, or e-traceability, of customer measurements to NIST high-dose measurement standards through the use of a measurement conversion factor (MCF) for Bruker e-scan instruments has been developed. The intent is that this factor will be incorporated into an Internet-based transfer dosimetry system, while still maintaining a reasonable and acceptable u...

Stable flows generalize the well-known concept of stable matchings to markets in which transactions may involve several agents, forwarding flow from one to another. An instance of the problem consists of a capacitated directed network, in which vertices express their preferences over their incident edges. A network flow is stable if there is no group of vertices that all could benefit from rero...