FINITE H-DIMENSION DOES NOT IMPLY EXPRESSIVE COMPLETENESS

Accepted versio

Logics for Unranked Trees: An Overview

Labeled unranked trees are used as a model of XML documents, and logical languages for them have been studied actively over the past several years. Such logics have different purposes: some are better suited for extracting data, some for expressing navigational properties, and some make it easy to relate complex properties of trees to the existence of tree automata for those properties. Furthermore, logics differ significantly in their model-checking properties, their automata models, and their behavior on ordered and unordered trees. In this paper we present a survey of logics for unranked trees

Combining Temporal Logics for Querying XML Documents

Abstract. Close relationships between XML navigation and temporal logics have been discovered recently, in particular between logics LTL and CTL ⋆ and XPath navigation, and between the µ-calculus and navigation based on regular expressions. This opened up the possibility of bringing model-checking techniques into the field of XML, as documents are naturally represented as labeled transition systems. Most known results of this kind, however, are limited to Boolean or unary queries, which are not always sufficient for complex querying tasks. Here we present a technique for combining temporal logics to capture nary XML queries expressible in two yardstick languages: FO and MSO. We show that by adding simple terms to the language, and combining a temporal logic for words together with a temporal logic for unary tree queries, one obtains logics that select arbitrary tuples of elements, and can thus be used as building blocks in complex query languages. We present general results on the expressiveness of such temporal logics, study their model-checking properties, and relate them to some common XML querying tasks.

withdrawn 2017 hrs ehra ecas aphrs solaece expert consensus statement on catheter and surgical ablation of atrial fibrillation

n/

Online monitoring of distributed systems with a five-valued LTL

In this paper, we deal with two kinds of uncertainties in distributed systems. On one hand, the order of causally unrelated executions is not determined when a global clock is not available. On the other hand, in a finite amount of time, the behaviour can be observed only up to a certain moment, and the future behaviour is unknown. In this paper, we investigate a monitoring approach based on linear temporal logic (LTL) specifications. We propose a five-valued semantics for LTL to deal with both kinds of uncertainties. We develop an efficient runtime verification algorithm using formula rewriting, and show the feasibility of our approach with a case study in the railway domain

Modeling for automated test generation - A comparison

In this contribution, we compare and analyze different methodologies of modeling for test generation. As an example, we use an industrial requirement specification given in natural language, which describes a safety function in a hybrid car. We model these requirements with three different paradigms and languages: as the specification imposes several timing constraints, we choose abstract State Machines, Timed Automata and UML2 State Machines to formalize the given requirements. From these models, we employ different tools for generating test cases, and compare the resulting test suites with respect to coverage and fault detection capabilities. We discuss the process of designing the models and the implications for professional software testing