Scielo RSS <![CDATA[International Journal of Combinatorial Optimization Problems and Informatics]]> vol. 6 num. 2 lang. es <![CDATA[SciELO Logo]]> <![CDATA[Books Content Manager of Open Access - Open Monograph Press]]> <![CDATA[Finding relevant features for identifying subtypes of Guillain-Barré Syndrome using Quenching Simulated Annealing and Partitions Around Medoids]]> Abstract: We present a novel approach to find relevant features for identifying four subtypes of Guillain-Barré Syndrome (GBS). Our method consists of a combination of Quenching Simulated Annealing (QSA) and Partitions Around Medoids (PAM), named QSA-PAM method. A 156-feature real dataset containing clinical, serological and nerve conduction test data from GBS patients was used for experiments. Different feature subsets were randomly selected from the dataset using QSA. New datasets created using these feature subsets were used as input for PAM to build four clusters, corresponding to a specific GBS subtype each. Finally, purity of clusters was measured. Sixteen features from the original dataset were encountered relevant for identifying GBS subtypes with a purity of 0.8992. This work represents the first effort to find relevant features for identifying GBS subtypes using computational techniques. The results of this work may help specialists to broaden the understanding of the differences among subtypes of GBS. <![CDATA[Semantic representations for knowledge modelling of a Natural Language Interface to Databases using ontologies]]> Abstract: Despite the large number of Natural Language Interfaces to Databases (NLIDB) that have been implemented, they do not guarantee to provide a correct response in 100% of the queries. In this paper, we present a way of semantic modelling the elements that integrate the knowledge of a NLIDB with the aim of increasing the number of correctly-answered queries. We design semantic representations in order to: a) model any relational database schema and its relationship with the natural language and b) add metadata to natural language words to enable our NLIDB to interpret natural language queries that contain superlatives. We configured our NLIDB in a relational database that we migrated from Geobase and used the Geoquery250 corpus to evaluate its performance. We compare its performance with the interfaces ELF, Freya and NLP-Reduce. The results indicate that our proposal allowed our NLIDB to obtain the best performance. <![CDATA[Stability of Connected Dominating Sets in the Presence of Static Nodes in a Mobile Ad hoc Network]]> Abstract: The topology of mobile ad hoc networks (MANETs) change dynamically with time. Connected dominating sets (CDS) are considered to be an effective topology for network-wide broadcasts in MANETs as only the nodes that are part of the CDS need to broadcast the message and the rest of the nodes merely receive the message. However, with node mobility, a CDS does not exist for the entire duration of the network session and has to be regularly refreshed (CDS transition). In an earlier work, we had proposed a benchmarking algorithm to determine a sequence of CDSs (Maximum Stable CDS) such that the number of transitions is the global minimum. In this research, we study the performance (CDS Lifetime and CDS Node Size) of the Maximum Stable CDS when a certain fraction of the nodes in the network are static and compare the performance with that of the degree-based CDSs. We observe the lifetime of the Maximum Stable CDS to only moderately increase (by a factor of 2.3) as we increase the percentage of the static nodes in the network; on the other hand, the lifetime of the degree-based CDS increases significantly (as large as 13 times) as we increase the percentage of static nodes from 0 to 80. <![CDATA[Home Automation Prototype Controlled by Mobile Devices for Disabled People]]> Abstract: In this work, the design and implementation of a domotic installation that is controlled by a mobile device is shown. This device controls different ambient variables inside a home without the need of new communication infrastructure. X-10 protocol is used for this purpose. This system uses a tablet as a graphical user interface (GUI) and by Bluetooth sends information to a metalanguage interface to do the information conversion from ASCII to X-10 codes. This X-10 code is sent through electrical wires to control different actuators. The bibliographic review shows data related to population aging and an increase in the quantity of disabled people, which is the main goal of this domotic development. This review shows up to date domotic applications and criteria for selection of X-10 technology, such as low cost, ease of installation and scalability. The system effectiveness is about 98% (testing 116 addresses and 9 different appliances) with an 86% effectiveness in devices with electrical motors driving mechanical loads.