1,542 research outputs found
Towards an Interdisciplinary Development of IoT-Enhanced Business Processes
IoT-enhanced Business Processes make use of sensors and actuators to carry out the process tasks and achieve a specific goal. One of the most important difficulties in the development of IoT-enhanced BPs is the interdisciplinarity that is demanded by this type of project. Defining an interdisciplinary tool-supported development approach that facilitates the collaboration of different professionals, with a special focus on three main facets: business process requirements, interoperability between IoT devices and BPs, and low-level data processing. The study followed a Design Science Research methodology for information systems that consists of a 6-step process: (1) problem identification and motivation; (2) define the objectives for a solution; (3) design and development; (4) demonstration; (5) evaluation; and (6) communication. The paper presents an interdisciplinary development process to support the creation of IoT-enhanced BPs by applying the Separation of Concerns principle. A collaborative development environment is built to provide each professional with the tools required to accomplish her/his development responsibilities. The approach is successfully validated through a case-study evaluation. The evaluation allows to conclude that the proposed development process and the supporting development environment are effective to face the interdisciplinary nature of IoT-enhanced BPs
Relaciones entre estrés académico, apoyo social, optimismo-pesimismo y autoestima en estudiantes universitarios
Strategies of the Spanish press in the face of the Twitter algorithm change. Analysis of tweets published between 2018-2020
Twitter recently celebrated its 15th anniversary. During this period, the platform has gone through several phases, culminating in a record number of subscribers and profits in 2021. Twitter is a household name all over the world and people know what it can or cannot provide, independent of the future growth that it may experience with new investments and updates. This article aims to verify two interrelated hypotheses, namely: the Spanish press already knows how to optimise the social network Twitter, as three decades have elapsed since its launch; and, secondly, the algorithm modification implemented by Twitter in 2018 has triggered a change in the positioning of the headers studied in this social network. In order to demonstrate both, the object of analysis will be conducted by a mixed approach through quantitative statistical processes (which will study the number of impacts and retweets and likes obtained), and inductive qualitative methods such as semi-structured interviews. This multidisciplinary approach will provide a more complete and in-depth analysis of the phenomenon. The research focuses on the period between 2018 and 2020, and addresses the participation on Twitter of the four main traditional newspapers (El País, La Vanguardia, ABC and El Mundo) as well as four native digital newspapers (20 Minutos, El Español, elDiario.es and El Huffpost). The analysis comprises more than 1.5 million tweets among the eight chosen newspapers.Twitter acaba de celebrar su decimoquinto aniversario. Durante este periodo, la plataforma ha pasado varias fases que han culminado con un récord de suscriptores y beneficios en 2021. El mundo conoce Twitter y sabe qué es lo que puede o no proporcionar, aparte de las posibilidades de crecimiento que pueda experimentar en caso de potenciales inversiones. En el presente artículo se pretende comprobar dos hipótesis interrelacionadas, a saber: la prensa española en castellano ya sabe cómo optimizar la red social Twitter, por haber transcurrido tres lustros desde su puesta en marcha; y, en segundo lugar, el cambio de algoritmo implementado por Twitter en 2018 que ha desencadenado un cambio de posicionamiento de las cabeceras estudiadas en esta red social. Con el propósito de demostrar ambas, se abordará el objeto de análisis desde un enfoque mixto a través de procesos cuantitativos estadísticos (que estudiarán el número de impactos y de retuits y likes obtenidos), y métodos cualitativos inductivos como entrevistas semiestructuradas a los responsables de redes de los medios involucrados. Esta aproximación mixta proporcionará un análisis más completo y profundo sobre el fenómeno. La investigación se centra en el período comprendido entre 2018 y 2020, y aborda la participación en Twitter de cuatro periódicos tradicionales (El País, La Vanguardia, ABC y El Mundo), así como de cuatro periódicos nativos digitales (20 Minutos, El Español, elDiario.es y El Huffpost). El análisis comprende más de 1,5 millones de tuits entre los ocho periódicos elegidos
Landmark vs. geometry learning: Explaining female rats' selective preference for a landmark
Rats were trained in a triangular-shaped pool to find a hidden platform, whose location was defined in terms of two sources of information, a landmark outside the pool and a particular corner of the pool. Subsequent test trials without the platform pitted these two sources of information against one another. In Experiment 1 this test revealed a clear, although selective, sex difference. As in previous experiments, females spent more time in an area of the pool that corresponded to the landmark, but here only when it was a cone but not when it was a pyramid. Males, on the other hand, always spent more time in the distinctive corner of the pool. Experiments 2 and 3 were only with female rats. In Experiment 2 two identical shaped cylinders were used as landmark cues (one plain white and the other vertically patterned with four different patterns). The results of the preference test revealed that only the females trained and tested with the plain cylinder spent more time in the area of the pool that corresponded to the landmark than in the distinctive corner of the pool. Finally, Experiment 3 replicated the results of Experiment 2 while eliminating an alternative explanation in terms of differential contrast between the two cylinders and the black curtain
Strong Water Absorption in the Dayside Emission Spectrum of the Planet HD 189733b
Recent observations of the extrasolar planet HD 189733b did not reveal the
presence of water in the emission spectrum of the planet. Yet models of such
'Hot Jupiter' planets predict an abundance of atmospheric water vapour.
Validating and constraining these models is crucial for understanding the
physics and chemistry of planetary atmospheres in extreme environments.
Indications of the presence of water in the atmosphere of HD 189733b have
recently been found in transmission spectra, where the planet's atmosphere
selectively absorbs the light of the parent star, and in broadband photometry.
Here we report on the detection of strong water absorption in a high
signal-to-noise, mid-infrared emission spectrum of the planet itself. We find
both a strong downturn in the flux ratio below 10 microns and discrete spectral
features that are characteristic of strong absorption by water vapour. The
differences between these and previous observations are significant and admit
the possibility that predicted planetary-scale dynamical weather structures
might alter the emission spectrum over time. Models that match the observed
spectrum and the broadband photometry suggest that heat distribution from the
dayside to the night side is weak. Reconciling this with the high night side
temperature will require a better understanding of atmospheric circulation or
possible additional energy sources.Comment: 11 pages, 1 figure, published in Natur
State selective electron injection in non-aggregated titanium phthalocyanine sensitised nanocrystalline TiO2 films
We describe a novel titanium phthalocyanine that shows no aggregation when anchored to nanocrystalline TiO2 films through its axial carboxylated ligand without the use of co-adsorbents; state selective electron injection into the TiO2 is demonstrated, resulting in efficient photocurrent generation in dye sensitised photoelectrochemical solar cells.Palomares Gil, Emilio J, [email protected]
Potentially inappropriate prescriptions according to explicit and implicit criteria in patients with multimorbidity and polypharmacy. MULTIPAP : a cross-sectional study
Background Multimorbidity is a global health challenge that is associated with polypharmacy, increasing the risk of potentially inappropriate prescribing (PIP). There are tools to improve prescription, such as implicit and explicit criteria. Objective To estimate the prevalence of PIP in a population aged 65 to 74 years with multimorbidity and polypharmacy, according to American Geriatrics Society Beers Criteria® (2015, 2019), the Screening Tool of Older Person’s Prescription -STOPP- criteria (2008, 2014), and the Medication Appropriateness Index -MAI- criteria in primary care. Methods This was an observational, descriptive, cross-sectional study. The sample included 593 community-dwelling elderly aged 65 to 74 years, with multimorbidity and polypharmacy, who participated in the MULTIPAP trial. Socio-demographic, clinical, professional, and pharmacological-treatment variables were recorded. Potentially inappropriate prescribing was detected by computerized prescription assistance system, and family doctors evaluated the MAI. The MAI-associated factors were analysed using a logistic regression model. Results A total of 4,386 prescriptions were evaluated. The mean number of drugs was 7.4 (2.4 SD). A total of 94.1% of the patients in the study had at least one criterion for drug inappropriateness according to the MAI. Potentially inappropriate prescribing was detected in 57.7%, 43.6%, 68.8% and 71% of 50 patients according to the explicit criteria STOPP 2014, STOPP 2008, Beers 2019 and Beers 2015 respectively. For every new drug taken by a patient, the MAI score increased by 2.41 (95% CI 1.46; 3.35) points. Diabetes, ischaemic heart disease and asthma were independently associated with lower summated MAI scores. Conclusions The prevalence of potentially inappropriate prescribing detected in the sample was high and in agreement with previous literature for populations with multimorbidity and polypharmacy. The MAI criteria detected greater inappropriateness than did the explicit criteria, but their application was more complex and difficult to automate.Publisher PDFPeer reviewe
Characterization of Nanocrystalline Cores for EMI Suppression in Cables
Electromagnetic interferences (EMI) can cause different kinds of problems in digital and analog systems, leading to malfunctions, system reboots, or even permanent damage to the system if this is not adequately designed or protected. Nowadays, most electronic products are connected to the main power network or are designed to be interconnected with others through cables. These cable interconnections are becoming more difficult due to the rigid restrictions related to the accomplishment of electromagnetic compatibility (EMC) compliance. When the cables of a system represent an EMI source, it cannot pass the conducted or radiated emissions test. A widely used technique to reduce these problems is applying an EMI suppressor such as a sleeve core. This EMI suppressor provides selective attenuation of undesired interference components that the designer may wish to suppress, and it does not significantly affect the intended signal. This contribution focuses on analyzing different nanocrystalline (NC) EMI suppressors’ performance intended for attenuating interferences in cables. Some NC novel samples are characterized and compare to MnZn and NiZn cores to determine this novel material’s effectiveness compared to the conventional ceramic solutions by analyzing samples with different dimensions
Performance Study of Split Ferrite Cores Designed for EMI Suppression on Cables
The ideal procedure to start designing an electronic device is to consider the electromagnetic compatibility (EMC) from the beginning. Even so, EMC problems can appear afterward, especially when the designed system is interconnected with external devices. Thereby, electromagnetic interferences (EMIs) could be transmitted to our device from power cables that interconnect it with an external power source or are connected to another system to establish wired communication. The application of an EMI suppressor such as a sleeve core that encircles the cables is a widely used technique to attenuate EM disturbances. This contribution is focused on the characterization of a variation of this cable filtering solution based on openable core clamp or snap ferrites. This component is manufactured by two split parts pressed together by a snap-on mechanism which turns this into a quick, easy to install solution for reducing post-cable assembly EMI problems. The performance of three different materials, including two polycrystalline (MnZn and NiZn) materials and nanocrystalline (NC) solution, are analyzed in terms of effectiveness when the solid sleeve cores are split. The possibility of splitting an NC core implies an innovative technique due to the brittleness of this material. Thus, the results obtained from this research make it possible to evaluate this sample's effectiveness compared to the polycrystalline ones. This characterization is carried out by the introduction of different gaps between the different split-cores and analyzing their behavior in terms of relative permeability and impedance. The results obtained experimentally are corroborated with the results obtained by a finite element method (FEM) simulation model with the aim of determining the performance of each material when it is used as an openable core clamp
Design and Study of a Wide-Band Printed Circuit Board Near-Field Probe
Magnetic near-field probes (NFP) represent a suitable tool to measure the magnetic field level from a small electromagnetic interference (EMI) source. This kind of antenna is useful as a magnetic field probe for pre-compliance EMC measurements or debugging tasks since the user can scan a printed circuit board (PCB) looking for locations with strong magnetic fields. When a strong H-field point is found, the designer should check the PCB layout and components placement in that area to detect if this could result in an EMI source. This contribution focuses on analyzing the performance of an easy to build and low-cost H-field NFP designed and manufactured using a standard PCB stack-up. Thereby, the frequency range and sensitivity of the NFP-PCB are analyzed through a Finite Element Method (FEM) simulation model that makes it possible to evaluate its sensibility and effective frequency range. The numerical results obtained with the FEM models are validated against measurements to verify the design and performance of our NFP. The FEM model reproduces the experimental procedure, which is used to evaluate the performance of the NFP in terms of sensitivity by means of the simulated near-field distribution. The NFP-PCB has almost a flat response from 180 MHz to 6 GHz, with an almost perfect concordance between numerical and experimental S21 results. The numerical results show an average transmission loss of −27.9 dB by considering the flat response bandwidth, whereas the experimental one is −29.7 dB. Finally, the designed NFP is compared to two high-quality commercial probes in order to analyze its performance
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