We present a semidefinite programming (SDP) approach for the problem of ordering vertices of a layered graph such that the edges of the graph are drawn as vertical as possible. This multi-level vertical ordering (MLVO) problem falls into the class of quadratic ordering problems. It is conceptually related to the well-studied problem of multi-level crossing minimization (MLCM), but offers certai...

Specification styles are an approach for structuring the design process of distributed systems. For different phases of the design process different specification styles are employed. In this paper we study tools that support the design process through support for specification style transformation. Tools were made for a subset of LOTOS.

This paper presents a new semantic model for real-time LOTOS, based upon a notion of timed observations. The novelty of the model is explained, as is its value. It differs from the usual operational models in that it permits an abstract, property-oriented view of processes. It differs from earlier denotational models in that it describes a wider variety of behaviours. It supports an alternative...

This paper introduces the LOTOS specification of the OSI95 Enhanced Transport Service. It discusses the problems encountered during its writing, such as the ones caused by its validation, or by the lack of a 'Timed' LOTOS. But the interest is not only in the specification itself. It also lies in the way this specification was developed: not after, but in parallel with the design of the Service ...

Mathematical models have been used in many areas of supply chain management. In this paper, we present a mixed-integer non-linear programing (MINLP) model to solve a multi-period, closed-loop supply chains (CLSCs) with two echelons consist of producers and customers. In order to satisfy the demands, the producers are be able to order for materials in the beginning of each period for one or more...

The topological ordering algorithm sorts nodes of a directed graph such that the order of the tail of each arc is lower than the order of its head. In this paper, we introduce the notion of covering between nodes of a directed graph. Then, we apply the topological orderingalgorithm on graphs containing the covering nodes. We show that there exists a cut set withforward arcs in these...

In stochastic (dynamic) traffic assignment (DTA), route choice (RC) formulations with implicit set require less memory than their explicit counterparts. To compute turn probabilities, however, a topological ordering of the nodes is needed, which negatively impacts stability convergence and consistency equilibrium. This paper formulates general framework for RC module efficient DTA (ESDTA) witho...

Two experiments investigated the locus of the effects of semantic integration (the conceptual relatedness between utterance constituents) on grammatical encoding during language production. In an ordering-error elicitation paradigm, participants produced descriptions of picture stimuli that varied in degree of integration. For both phrase and word ordering errors, integrated stimuli were more e...