Carme Martín

LEARN-SQL: Automatic Assessment of SQL Based on IMS QTI Specification

In this paper we present LEARN-SQL, a system conforming to the IMS QTI specification that allows on-line learning and assessment of students on SQL skills in an automatic, interactive, informative, scalable and extensible manner.

Applying Transition Rules to Bitemporal Deductive Databases for Integrity Constraint Checking

A bitemporal deductive database is a deductive database that supports valid and transaction time. A set of facts to be inserted and/or deleted in a bitemporal deductive database can be done in a past, present or future valid time. This circumstance causes that the maintenance of database consistency becomes more hard. In this paper, we present a new approach to reduce the difficulty of this problem, based on applying transition and event rules, which explicitly define the insertions and deletions given by a database update. Transition rules range over all the possible cases in which an update could violate some integrity contraint. Although, we have a large amount of transition rules, for each one we argue its utility or we eliminate it. We augment a database with this set of transition and event rules and then standard SLDNF resolution can be used to check satisfaction of integrity constraints.

An integrity constraint checking method for temporal deductive databases

The authors propose a method for integrity checking in the context of temporal deductive databases. A temporal deductive database is a deductive database that supports some aspect of time, in our case valid time, in which valid time is the time when the fact is true in the modelled reality. Their method augments a database with a set of transition and event rules, which explicitly define the insertions and deletions by database update. Standard SLDNF resolution can then be used to check satisfaction of integrity constraints. A temporal deductive database has to be consistent, that is, after performing an update the database must satisfy its set of integrity constraints. Using their method the temporal deductive database is always consistent because if a retroactive or proactive update violated some integrity constraint the update would be rejected.

A Temporal Study of Data Sources to Load a Corporate Data Warehouse

The input data of the corporate data warehouse is provided by the data sources, that are integrated. In the temporal database research area, a bitemporal database is a database supporting valid time and transaction time. Valid time is the time when the fact is true in the modeled reality, while transaction time is the time when the fact is stored in the database. Defining a data warehouse as a bitemporal database containing integrated and subject-oriented data in support of the decision making process, transaction time in the data warehouse can always be obtained, because it is internal to a given storage system. When an event is loaded into the data warehouse, its valid time is transformed into a bitemporal element, adding transaction time, generated by the database management system of the data warehouse. However, depending on whether the data sources manage transaction time and valid time or not, we could obtain the valid time for the data warehouse or not. The aim of this paper is to present a temporal study of the different kinds of data sources to load a corporate data warehouse, using a bitemporal storage structure.

AETAS: A System for Semanticizing Temporal Expressions from Unstructured Contents

AETAS is an online tool for converting text into RDF linked data with resolution of temporal expressions. AETAS follows fully SOA architecture and is accessible via web-service. It implements a novel approach for semantic representation and linked temporal graphs built from natural language sentences. In this paper, we present a demonstration tool, which combines the normalized temporal expressions with linguistic semantic frames and creates a linked RDF graph where time is defined as an individual dimension. The tool is based on SUTime which identifies and normalizes the temporal expressions and on FreeLing, a linguistic processor which extracts the semantics of sentences. The output of AETAS is a set of time-enriched triples that can be stored in a RDF database for later \(\tau \)-SPARQL querying.

A learning tool to develop sustainable projects

This paper presents a tool developed to help engineers to design and develop sustainable projects. The tool has been designed to introduce and evaluate the sustainability of engineering projects in general, but here we show its application to assess the final project of an engineering degree. This tool is a guide for students to introduce and estimate the sustainability of their projects, but it also helps teachers to assess them. The tool is based on the Socratic Methodology and consists of a matrix where each cell contains several questions that students must consider during the project development and which they must answer in their project report. A positive or negative mark is assigned to every cell, and the sum of all marks states the project sustainability. However, the result is not as simplistic as a final number, but a descriptive sustainability analysis where questions are answered and every mark justified. A pilot test with some students has obtained good results, but the first Final Degree Project using this methodology will be read in July 2016.