Na súa propia pel: contribucións autobiográficas á Guerra Civil. Conformación dunha narrativa singular

Through a collection of 16 stories, this article contains autobiographical anecdotes by a group of writers who survived the Spanish Civil War.En este artículo se pretende, a través de un conjunto de 16 narraciones, ofrecer la visión autobiográfica de un grupo de autores que decidieron poner por escrito sus vivencias de supervivencia en la época de la Guerra Civil.Neste artigo preténdese, a través dun conxunto de 16 narracións, ofrecer a visión autobiográfica dun grupo de autores que decidiron pór por escrito as súas vivencias de supervivencia na época da Guerra Civil

El cronista de la noche: la temática de Henri de Toulouse-Lautrec

Como indica el título de este trabajo, el principal propósito es el estudio de las temáticas que se han considerado más relevantes y sustanciales dentro de la obra de Toulouse-Lautrec, todas ellas unidas por el hilo conductor del ambiente nocturno. No obstante, cabe destacar que, por tanto, no se trata de un trabajo genérico acerca de la vida y la obra de un artista, sino que se centra exclusivamente en la temática de su obra al considerarlo un aspecto mucho más ameno y atrayente a la hora de abordar el trabajo. Así, aunque no se trata de un relato biográfico acerca de Toulouse-Lautrec, sí se ha considerado imprescindible mencionar aquellos aspectos de su vida que se encuentran estrechamente ligados al desarrollo y compresión de sus temas. De esta manera, el trabajo plantea cuatro de las temáticas más importantes de su obra, aunque también hay otras interesantes que no se han podido desarrollar por cuestiones de extensión, y todas ellas giran en torno a lo nocturno: los salones de baile, el cartel, la prostitución y el circo. En lo referente a las temáticas de los cabarets y del mundo de la prostitución, la vinculación al ambiente nocturno es más que evidente, sin embargo, las otras dos temáticas constituyen también una relación mucho más sutil y aparentemente oculta. En el caso de la temática del 3 cartel, aunque ya se desarrollará más adelante, es incuestionable el vínculo tan estrecho que se produjo entre la amplia gama de espectáculos y formas de ocio nocturnas con este medio publicitario (al igual que las estrellas más importantes del momento fueron las protagonistas en ambos casos). Por otro lado, el circo, otra de las formas de entretenimiento y de espectáculo más importantes de la época, guarda una profunda relación con algunas de las características más repetidas por Lautrec en sus escenas nocturnas: la incomprensión, la soledad, el misterio, lo sórdido y lo trascendental de la existencia humana

Indoor Air Quality Assessment: Comparison of Ventilation Scenarios for Retrofitting Classrooms in a Hot Climate

Current energy e ciency policies in buildings foster the promotion of energy retrofitting of the existing stock. In southern Spain, the most extensive public sector is that of educational buildings, which is especially subject to significant internal loads due to high occupancy. A large fraction of the energy retrofit strategies conducted to date have focused on energy aspects and indoor thermal comfort, repeatedly disregarding indoor air quality criteria. This research assesses indoor air quality in a school located in the Mediterranean area, with the objective of promoting di erent ventilation scenarios, based on occupancy patterns and carbon dioxide levels monitored on site. Results show that manual ventilation cannot guarantee minimum indoor quality levels following current standards. A constant ventilation based on CO2 levels allows 15% more thermal comfort hours a year to be reached, compared to CO2-based optimized demand-controlled ventilation. Nevertheless, the latter ensures 35% annual energy savings, compared to a constant CO2-based ventilation, and 37% more annual energy savings over that of a constant ventilation rate of outdoor air per person

Assessment of Indoor Environmental Quality for Retrofitting Classrooms with An Egg-Crate Shading Device in A Hot Climate

In the Mediterranean climate, a large number of educational buildings suffer from discomfort due mostly to energy-deficient thermal envelopes and a lack of cooling systems. Impending climate change is expected to worsen overheating in classrooms, especially during heatwave periods. Therefore, the protection of window openings to reduce incident solar radiation while maintaining adequate indoor environmental quality must be considered a necessary key focus. The main objective of this research is to assess the influence of an egg-crate shading device on the indoor environmental quality of a classroom in Southern Spain. To do so, two classrooms—with and without this shading device—were simultaneously monitored over a whole year. The implementation of an egg-crate shading device allowed for a significant reduction of the incident solar radiation, both in summer and mid-season (around 45–50%), which objectively slightly conditioned indoor operative temperatures. Given the noticeable influence of the user patterns observed, indoor illuminance was also improved, as the rolling shutters tended to be opened at higher aperture levels

Analysis of a frequency divider by two based on a differential nonlinear transmission line

A recently proposed frequency divider by two, based on differential nonlinear transmission line, acting like a reflective distributed resonator, is analyzed in-depth. The flip bifurcation locus of a single cell is obtained analytically, which enables an understanding of the divider behavior and an initial estimation of its element values. The possibility to modify the division threshold and bandwidth through the proper selection of an additional linear capacitor is demonstrated. The influence of the number of cells on the division bandwidth and on the generated standing wave at the subharmonic frequency is also investigated. The techniques have been applied to two frequency divider with 1.5 and 2.2 GHz input frequency.Spanish project TEC2011-29264-C03-01 for financial support

Oscillation modes in symmetrical wireless-locked systems

Time synchronization of multiple elements of a wireless network can be achieved through the wireless coupling of their oscillator circuits. Most previous works on wireless locking of oscillators analyze the system in an idealized manner, representing the oscillator elements with phase models and describing the propagation effects with constant scalar coefficients and time delays. Here, a realistic analysis of the wireless system is presented, which relies on the extraction of the oscillator models from harmonic-balance (HB) simulations and takes into account the antenna gains and propagation effects. The most usual network configurations, corresponding to ring, fully connected, and star topologies, are investigated in detail. In symmetric conditions, the oscillation modes are detected through an eigenvalue/eigenvector calculation of an equivalent coupling matrix. For each particular mode, the system is analyzed in the following manners: by means of an analytical formulation, able to provide all the coexistent solutions, and through a circuit-level HB simulation of an equivalent system with a reduced number of oscillator elements. The stability properties are determined by means of a perturbation system of general application to any coupled structure. A specific formulation is also derived to predict the impact of discrepancies between the oscillator elements. All the results have been validated with independent circuit-level simulations and measurements.This work was supported in part by the Spanish Ministry of Economy and Competitiveness under the research project TEC2017-88242-C3-1-R, in part by the European Regional Development Fund (ERDF/FEDER), in part by Juan de la Cierva Research Program under IJCI-2014-19141, and in part by the Parliament of Cantabria under the project Cantabria Explora 12.JP02.64069

Stability analysis of wireless coupled-oscillator circuits

Distributed synchronization of sensor networks can be achieved by coupling the oscillator signals of the sensor nodes. Previous works describe the coupling effects in an idealized manner, with constant scalar coefficients. Here a realistic analysis of the coupled-system dynamics is presented for the first time to our knowledge, taking into account the antenna gains and propagation effects on the amplitude and phase values of the equivalent current sources, injecting the oscillator elements. The new formulation provides the synchronized oscillation frequency and amplitude and phase distributions of the coupled system. Distinct oscillation modes, with different phase shifts between the oscillator elements, are identified, associated with the system symmetry. The stability properties of these modes change with the distance between the oscillator elements. The possibility to impose in-phase operation by tuning of the oscillator elements is demonstrated. Good agreement is obtained between simulation and measurements.The authors would like to thank to Spanish Ministry of Economy and Competitiveness for their financial support under the research project TEC2014-60283-C3-1-R, the European Regional Development Fund (ERDF/FEDER), Juan de la Cierva Research Program IJCI-2014-19141 and the Parliament of Cantabria for financial support under the project Cantabria Explora 12.JP02.64069

Pulsed-waveform generator based on coupled oscillators

Waveform sharpening in nonlinear transmissionlines (NLTL) is analyzed in detail and applied to the design of apulse-generator based on two coupled oscillators. The maximumpropagation frequency through the NLTL is calculated with arealistic numerical technique, which enables an optimized design.By coupling two NLTL oscillators terminated in grounded stubsof different length, three design parameters are available, whichenables a flexible mechanism for pulse formation. A reducedordermodel is proposed for the efficient determination of thetuning voltage in one of the oscillator elements. The analysis anddesign techniques have been applied to a prototype at 0.8 GHz.Spanish project TEC20 11-29264-C03-01 for financial support

Analysis of self-injection locked oscillators for motion sensing applications

Self-injection locked oscillators have been recently proposed for motion sensing applications demonstrating a good experimental performance. Here a detailed investigation of the system dynamics is presented using a realistic model of the oscillator circuit under the injection of the reflected signal, which is phase modulated due to the target motion. The instability effects observed for some distance values are studied by means of a perturbation method and the results are validated through comparison with full circuit-level simulations and with measurements. The regular operation ranges are efficiently determined through a bifurcation analysis in terms of the distance to the target and the antenna gain. The modulation effect is analyzed with a reduced-order envelope transient formulation that copes with the accuracy problems associated with the small values of the modulation frequency. Very good agreement has been obtained with the experimental results.The authors would like to thank to Spanish Ministry of Economy and Competitiveness for their financial support under the research project TEC2014-60283-C3-1-R and Juan de la Cierva Research Program IJCI-2014-19141 and the Parliament of Cantabria for financial support under the project Cantabria Explora 12.JP02.64069

Analysis of two coupled NLTL-based oscillators

A system of two coupled oscillators based on nonlinear transmission lines (NLTL) is proposed for pulsed-shaping applications. The maximum propagation frequency through the NLTL is calculated and optimized with a realistic numerical method. With additional design considerations, this is used to increase the waveform steepening capabilities of the NLTL and obtain an oscillator based on the shockwave concept. Coupling two of these oscillators with slightly different characteristics various pulse shapes can be achieved through composition of the individual waveforms. The coupled-system behavior is understood with the aid of a new reduced-order formulation, which takes into account the differences between the oscillator elements. The formulation is extended for stability and phase-noise analysis. It provides valuable insight into the impact of the individual oscillator characteristics on the coupled-system dominant poles and unsymmetrical stable phase-shift range. It also explains the variation of the spectral density with the phase shift, as well as the mechanisms for the phase noise corners observed when increasing the offset frequency. A more realistic analysis of the coupled system is also carried out with the conversion-matrix approach, using cyclostationary noise sources. The analysis and design techniques have been applied to several prototypes at 0.8 GHz.This work was supported by the Spanish Ministry of Science and Innovation under project TEC2011-29264-C03-01