REINA at RepLab2013 Topic Detection Task: Community Detection

[EN]Social networks have become a large repository of comments which can extract multiple information. Twitter is one of the most widespread social networks and larger and is therefore an important source for detecting states of opinion, events and happenings before even the mainstream media. Topic detection is important to discover areas of interest that arise in the tweets. We have used classical systems for a similarity matrix and we have used community detection techniques. The results have been good and allows us to study new possibilities

Scientific culture: Public perception of Science and Technology in Spanish Wikipedia

[ES]La presentación recoge las relaciones existentes dentro de los artículos de ciencia y tecnología de la Wikipedia aplicando técnicas de Análisis de las redes sociales

Science and Technology in Social Networks: Twitter

[ES]El uso de Internet como fuente principal de búsqueda de información científica se ve reforzado con el uso de los redes sociales. Esta situación requiere un estudio y estandarización del contenido obtenido por esta vía. A través del estudio de los perfiles de twitter que difunden información científica se pueden identificar los temas principales y la cantidad y calidad de la información científica compartida

REINA at CLEF 2007 Robust Task

Describe el trabajo que el Grupo de Investigación REINA de la Universidad de Salamanca presentó en CLEF 2007 sobre sistemas de recuperación de información monolingüe (Inglés, Francés y Portugués) y bilingüe (Inglés al Francés). Muestra los resultados obtenidos en las evaluaciones aplicando técnicas de expansión local.This paper describes our work at CLEF 2007 Robust Task. We have participated in the monolingual (English, French and Portuguese) and the bilingual (English to French) subtask. At CLEF 2006 our research group obtained very good results applying local query expansion using windows of terms in the robust task. This year we have used the same expansion technique, but taking into account some criteria of robustness: MAP, GMAP, MMR, GS@10, P@10, number of failed topics, number of topics bellow 0.1 MAP, and number of topics with P@10=0. In bilingual retrieval experiments threemachine translation programs were used to translate topics. For the target language, translations were merged before performing a monolingual retrieval. We also applied the same local expansion technique. This year the results were disappointing. We think out that the reason is the difficulty to select the best measurement for robustness. Perhaps the problem is that all measurements are average results over all topics, but thehard topics are inherently hard and must be analyze separately. This year all our runs also ends up in good ranking, both base runs and expanded ones. We think that the reason is that we used a good information retrieval system, and the expansion technique is robust because it does not deteriorate significantly the retrieval performance

Coupled-oscillator model to analyze the interaction between a quartz resonator and trapped ions

The novel application of a piezoelectric quartz resonator for the detection of trapped ions has enabled the observation of the quartz-ions interaction under nonequilibrium conditions, opening new perspectives for high-sensitive motional frequency measurements of radioactive particles. Energized quartz crystals have (long) decay-time constants in the order of milliseconds, permitting the coherent detection of charged particles within short time scales. In this paper we develop a detailed model governing the interaction between trapped 40Ca+ ions and a quartz resonator connected to a low-noise amplifier. We apply this model to experimental data and extract the ions’ reduced-cyclotron frequency in our 7-T Penning trap setup. We also obtain an upper limit for the coupling constant g with the present quartz-amplifier-trap (QAT) configuration. The study of the reduced-cyclotron frequency is especially important for the use of this resonator in precision Penning-trap mass spectrometry. The improvement in sensitivity can be accomplished by increasing the quality factor of the QAT configuration, which in turn will improve the performance of the system towards the strong-coupling regim

Reformulation of queries using similarity thesauri

Este artículo trata sobre la recuparación de la información en thesaurus similares.One of the major problems in information retrieval is the formulation of queries on thepart of the user. This entails specifying a set of words or terms that express their informationalneed. However, it is well-known that two people can assign different terms to refer tothe same concepts. The techniques that attempt to reduce this problem as much as possiblegenerally start from a first search, and then study how the initial query can be modified toobtain better results. In general, the construction of the new query involves expanding theterms of the initial query and recalculating the importance of each term in the expandedquery. Depending on the technique used to formulate the new query several strategies aredistinguished. These strategies are based on the idea that if two terms are similar (withrespect to any criterion), the documents in which both terms appear frequently will also berelated. The technique we used in this study is known as query expansion using similaritythesauri

Formation of two-ion crystals by injection from a Paul-trap source into a high-magnetic-field Penning trap

Two-ion crystals constitute a platform for investigations of quantum nature that can be extended to any ion species or charged particle provided one of the ions in the crystal can be directly laser cooled and manipulated with laser radiation. This paper presents the formation of two-ion crystals for quantum metrology in a 7-tesla open-ring Penning trap. 40Ca+ ions are produced either internally by photoionization or externally in a (Paul-trap) source, transported through the strong magnetic field gradient of the superconducting solenoid, and captured in-flight with a mean kinetic energy of a few electronvolts with respect to the minimum of the Penning-trap potential well. Laser cooling of the two-ion crystal in a strong magnetic field towards reaching the quantum regime is also presented, with particular emphasis on the cooling of the radial modes.Spanish Government PID2019-104093GB-I00/AEI/10.013 39/501100011033Andalusian Government P18FR-3432 PTA2018-016573-IFondo Operativo FEDER A-FQM-425-UGR18Spanish Government FPU17/02596University of Granada "Plan Propio -Programa de Intensificacion de la Investigacion" PP2017-PRI.I-04Laboratorios Singulares 2020European Research Council (ERC) European Commission 278648TRAPSENSOR MICINN/FEDER/UGR FPA2015-67694-P FPA2012-32076 UNGR10-1E501 UNGR13-1E-1830 EQC2018-005130-PJunta de AndaluciaEuropean Commission IE-5713 IE2017-5513Spanish MICINN ("Beatriz Galindo" Fellowship) BEAGAL18/00078German Research Foundation (DFG)European Commission SFB/CRC 122