Search results for "Information System"
showing 10 items of 2404 documents
The complexity of graph languages generated by hyperedge replacement
1990
Although in many ways, hyperedge replacement graph grammars (HRGs) are, among all graph generating mechanisms, what context-free Chomsky grammars are in the realm of string rewriting, their parsing problem is known to be, in general, NP-complete. In this paper, the main difficulty in HRG parsing is analysed and some conditions on either grammar or input graphs are developed under which parsing can be done in polynomial time. For some of the cases, the parsing problem is shown to be log-space reducible to context-free string parsing.
Universal Organic Solvent−Water Partition Coefficient Model
1999
A method that permits a semiquantitative estimate of the partitioning of any solute between any two media is presented. As an example, the organic solvent-water partition coefficients P are calculated. Program GSCAP is written as a version of Pascal's SCAP program. The only needed parameters are the dielectric constant and molecular volume of the organic solvent. The log P results are compared with the Pomona database. The average absolute deviation is 1.48 log units and the standard deviation is 1.66 log units.
Embedded access points for trusted data and resources access in HPC systems
2010
Biometric authentication systems represent a valid alternative to the conventional username-password based approach for user authentication. However, authentication systems composed of a biometric reader, a smartcard reader, and a networked workstation which perform user authentication via software algorithms have been found to be vulnerable in two areas: firstly in their communication channels between readers and workstation (communication attacks) and secondly through their processing algorithms and/or matching results overriding (replay attacks, confidentiality and integrity threats related to the stored information of the networked workstation). In this paper, a full hardware access poi…
Mobile Banking and Payment System : A Conceptual Standpoint
2017
This study conceptualizes and proposes a well-regulated and designated mobile banking and payment system (MBPS) with the potential to strengthen the banking system, foster the regulatory framework, and to be integrated across various platforms and mobile devices. Unlike other mobile payment systems that lack convenience, scalability, and usability, the proposed MBPS contains several important functionalities and it has the potential to bring together hitherto unconnected industries—banking, Fintech and telecoms—to offer value-added services to their existing and potential customers. The ownership of the MBPS shall remain with the financial services sector including the banking and microfina…
Outdoor, but not indoor, nitrogen dioxide exposure is associated with persistent cough during the first year of life
2011
Background and aims: Because their lungs and immune system are not completely developed, children are more susceptible to respiratory disease and more vulnerable to ambient pollution. We assessed the relation between prenatal and postnatal nitrogen dioxide (NO2) levels and the development of lower respiratory tract infections (LRTI), wheezing and persistent cough during the first year of life. Methods: The study population consisted of 352 children from a birth cohort in Valencia, Spain. Prenatal exposure to NO2, a marker of traffic related air pollution was measured at 93 sampling sites spread over the study area during four different sampling periods of 7 days each. It was modeled for eac…
Complex Dynamics in a Harmonically Excited Lennard-Jones Oscillator: Microcantilever-Sample Interaction in Scanning Probe Microscopes1
1998
In this paper we model the microcantilever-sample interaction in an atomic force microscope (AFM) via a Lennard-Jones potential and consider the dynamical behavior of a harmonically forced system. Using nonlinear analysis techniques on attracting limit sets, we numerically verify the presence of chaotic invariant sets. The chaotic behavior appears to be generated via a cascade of period doubling, whose occurrence has been studied as a function of the system parameters. As expected, the chaotic attractors are obtained for values of parameters predicted by Melnikov theory. Moreover, the numerical analysis can be fruitfully employed to analyze the region of the parameter space where no theoret…
Correlation of oscillatory behaviour in Matlab using wavelets
2014
Here we present a novel computational signal processing approach for comparing two signals of equal length and sampling rate, suitable for application across widely varying areas within the geosciences. By performing a continuous wavelet transform (CWT) followed by Spearman?s rank correlation coefficient analysis, a graphical depiction of links between periodicities present in the two signals is generated via two or three dimensional images. In comparison with alternate approaches, e.g., wavelet coherence, this technique is simpler to implement and provides far clearer visual identification of the inter-series relationships. In particular, we report on a Matlab? code which executes this tec…
The usage of Twitter from the Spanish media during the elections
2018
Los medios de comunicación tradic ionales han adoptado Twitter c omo otro canal por el que difundir su información y llegar hasta las audiencias digit ales. Este estudio tiene como objetivo analizar las características de los tuits publicados por los me dios españoles durante doce meses en los que se producen dos procesos electorales, para comprobar las di ferencias en la utilización de esta plataforma según el contenido de la cobertura y la fase en que se publica. La investigación se fundamenta en una metodología cua ntitativa, en la que se implem enta un análisis de contenido computarizado de las publicacione s en Twitter que hacen los dis tintos tipos de medios entre 2015 y 2016. Los res…
#lasperiodistasparamos, gestación de una conciencia profesional feminista
2020
Se analiza la gestación y consolidación del activismo feminista que ha aglutinado a miles de profesionales de la comuni-cación en España a raíz de la huelga del 8 de marzo de 2018, unidas a través de la aplicación de mensajería Telegram y por el hashtag #lasperiodistasparamos en la red de microblogging Twitter. Se ha llevado a cabo un análisis del discurso de los 13.163 tweets publicados de febrero a septiembre de 2018 con esa etiqueta. También se ha analizado el conteni-do de las conversaciones en su canal de Telegram. Se aportan las opiniones formuladas en entrevistas en profundidad a 20 activistas de esta cibercomunidad. A través de una metodología cuantitativa y cualitativa aplicada a c…
Sensacionalismo o servicio público en las informaciones sobre menores desaparecidos
2017
Missing children pose to journalists the challenge of reporting on facts that offer high human interest, but this requires rigor and caution. Media coverage can exploit the emotional components of the event in order to increase the audience or it can cooperate with the investigation by facilitating citizen collaboration and avoiding speculation. This paper examines the key features in this kind of news and information for this article is drawn from the study of four Spanish newspapers’ (El pais, ABC, La vanguardia, and El periodico) coverage about the 15 missing cases reported in the SOS Desaparecidos association’s website –which all occurred between 1977 and 2015. The analysis detects an u…