Capacitance Spectroscopy for MOS Systems

Producción CientíficaCapacitance studies of metal–oxide–semiconductor (MOS) capacitors have been used since the early 60s of the past century to investigates the interface surface states, oxide charge and electron and ion phenomena in these structures. This chapter provides detailed information about the theoretical basis, and examples of application of capacitance spectroscopy techniques in a variety of MOS systems

\u3cem\u3eBataclanismo\u3c/em\u3e! Or, How Deco Bodies Transformed Postrevolutionary Mexico City

In the spring of 1925, Santa Anita\u27s Festival of Flowers seemed to follow its tranquil trend of previous years. The large displays of flowers, the selection of indias bonitas (as the contestants of beauty pageants organized in an attempt to stimulate indigenism were known) and the boat-rides on the Viga Canal, all communicated what residents of neighboring Mexico City had come to expect of the small pueblo in the Federal District since the Porfiriato: the respite of a peaceful pastoral, the link to a colorful past, and the promise that mexicanidad was alive and well in the campo. Unfortunately, wrote Manuel Rámirez Cárdenas of El Globo, the modern newspaper, the next day, this idyllic tradition was rudely interrupted by a group of audacious, scantily clad women. The culprits were actresses of Mexico City\u27s Lírico theater, who walked around Santa Anita\u27s streets in picaresque clothing —stage outfits that left little to the imagination, particularly in broad daylight—and upset visitors and campesinos alike. According to Cárdenas, abuelitas and mamás were shocked by the display, averting their eyes from the female spectacle in fear of el pecado mortal. Thankfully, for the mothers and grandmothers in the audience, the festival continued in predictable fashion after the initial uproar. Organizers continued with the traditional dances, and judges selected an india bonita from a pool of young, decente mestizo girls to represent the pueblo and the festival. Unbeknownst to the residents of rural Santa Anita, the daring actresses of El Lírico were part of a new phenomenon that had swept through Mexico City like wildfire, turned the entertainment world upside down, and pushed many to reconsider what constituted female beauty, decency, and lo mexicano. A few months earlier, on February 12th, a grand variety spectacle named Voilá Paris: La Ba-ta-clán premiered in Teatro Iris and instantly sent shock waves throughout the Mexican entertainment world and the larger metropolis. The show featured seminude and nude French actresses, who performed dances and acts that appeared to be a mix of classical ballet, Ziegfeld Follies chorus lines, and tableaux vivants. Within weeks, Mexican copycat productions capitalized on the enormous success of the show, triggering a new entertainment phenomenon named after the original production: Bataclanismo. It also launched a new kind of female star, the bataclana, who came to represent the erotic, and more dangerous, attributes of the flapper for Mexican audiences, and whose body became the site of contested and divergent notions of modernity. In this article, I explore bataclanismo as a normative discourse that reached far beyond the theater into the practice of everyday life. I do so to gauge the transition of changing ideals of femininity in Mexico from 1925 to 1935, and the influence these changes had on the development of urban space. Drawing on Elizabeth Grosz\u27 and Doreen Massey\u27s insights that place and gender are mutually constitutive, this article examines the articulation between the embodied city and changing gender norms in the wake of both the Mexican revolution and the advent of twentieth-century global capital. Analyzing these relationships from Judith Butler\u27s perspective of gender performance, especially as read through bodies, I argue that a new transnational aesthetic of feminine embodiment celebrated in bataclanismo influenced a distinct urban modernity and sociability in Mexico City. This new ideal female physique that stressed length, height, and androgyny—what I term a Deco body—helped to reconfigure Mexico City in terms of gender, space and race. It ushered in new gender ideals, helped visualize urban modernity, and bridged the gap between two divergent discourses that accompanied revolutionary reform, indigenismo and mestizaje, paving the way for a mestizo modernity

Revisión de la incidencia de la Peste Negra (1348) en Navarra a través de un modelo matemático de población

[ES] En este artículo se somete a revisión la incidencia de la Peste Negra de 1348 en Navarra, confrontando los datos empíricos que diversos autores han facilitado con un modelo matemático de población. Esta confrontación, así como las informaciones contradictorias que se desprenden de la historiografía actual sobre Navarra, permiten asegurar que la incidencia del morbo en esta zona tuvo que ser necesariamente bastante inferior a la que comúnmente se acepta, sin que esto signifique negar las graves repercusiones que la peste tuvo en el viejo reino pirenaico.[EN] The paper presents a revision of the impact of the Black Death of 1348 on Navarre by contrasting the empirical data provided by several authors with a mathematical model of population dynamics. This comparison, together with the contradictory information found in present-day historiography about Navarre, leads to the conclusion that the mortality in the area must have been much lower than has traditionally been accepted. This however does not imply underestimating the serious consequences of the plague on the life of the ancient Pyrenean kingdom

Programming Pulse Width Assessment for Reliable and Low-Energy Endurance Performance in Al:HfO2-Based RRAM Arrays

A crucial step in order to achieve fast and low-energy switching operations in resistive random access memory (RRAM) memories is the reduction of the programming pulse width. In this study, the incremental step pulse with verify algorithm (ISPVA) was implemented by using different pulse widths between 10 μ s and 50 ns and assessed on Al-doped HfO 2 4 kbit RRAM memory arrays. The switching stability was assessed by means of an endurance test of 1k cycles. Both conductive levels and voltages needed for switching showed a remarkable good behavior along 1k reset/set cycles regardless the programming pulse width implemented. Nevertheless, the distributions of voltages as well as the amount of energy required to carry out the switching operations were definitely affected by the value of the pulse width. In addition, the data retention was evaluated after the endurance analysis by annealing the RRAM devices at 150 °C along 100 h. Just an almost negligible increase on the rate of degradation of about 1 μ A at the end of the 100 h of annealing was reported between those samples programmed by employing a pulse width of 10 μ s and those employing 50 ns. Finally, an endurance performance of 200k cycles without any degradation was achieved on 128 RRAM devices by using programming pulses of 100 ns width

Controlling the intermediate conductance states in RRAM devices for synaptic applications

Producción CientíficaRRAM devices are promising candidates to implement artificial synaptic devices for their use in neuromorphic systems, due to their high number or reachable conductance levels. The capacitors used in this work (TiN/Ti/ HfO2/W) show resistive switching behavior and reachable intermediate conductance states. We can control the conductance states by applying voltage pulses to the top electrode. Different approaches to control the synaptic weight have been studied: applying pulses with different voltage amplitudes changes the synaptic weight variation in an exponential way, and applying pulses with different lengths changes the synaptic weight in a linear way. We can control the conductance values when applying depression pulses, but the potentiation characteristic is not linear, as for other synaptic devices, as PRAMs. Applying other voltage signals to the structure, as voltage ramps, can improve the potentiation characteristic.Ministerio de Economía, Ciencia y Competitividad - Fondo Europeo de Desarrollo Regional (project TEC2017-84321-C4-2-R

2020 IEEE Latin America Electron Devices Conference (LAEDC)

Producción CientíficaArtificial synaptic devices used in neuromorphic systems need a high number of reachable conductance levels. Resistive switching devices are promising candidates to implement these devices due to their reachable conductance levels. In this work, we have used TiN/Ti/HfO 2 /W capacitors to study the control of the intermediate conductance states using current pulses instead of the usual voltage pulses. Unlike the use of voltage pulses, in this case we can control the HRS to LRS transition (potentiation characteristic). The characteristic is clearly linear when applying current pulses with linearly increasing amplitudes. The potentiation characteristic is not affected by the pulse length, even for lengths lower than 1 μs. In terms of peripheral circuitry, it is desirable to use pulses with identical amplitudes, but in this case no accumulative behavior is observed, and one current pulse is enough to carry the device to the final conductance state achieved for the amplitude used. Finally, it is not possible to control the HRS to LRS transition (depression characteristic) using current pulses due to the abrupt reset transition. However, this transition can be well controlled using voltage pulses.Ministerio de Economía, Industria y Competitividad - Fondo Europeo de Desarrollo Regional (grant TEC2017-84321- C4-2-R

Control of the set and reset voltage polarity in anti-series and anti-parallel resistive switching structures

Producción CientíficaIn the attempt to control the polarity of the set and reset voltages in bipolar resistive switching capacitors, we have studied the switching properties of structures consisting of either two anti-series or two anti-parallel metal-insulator-metal capacitors. The capacitors were based on hafnium oxide, and W and TiN/Ti were used as bottom and top electrodes respectively. MIM capacitors showed bipolar resistive switching behavior, with very good repetitiveness and endurance properties. Both anti-series and anti-parallel structures showed again bipolar resistive switching behavior, being the polarity of the set and reset voltages controllable by applying higher biases. In the case of anti-series configuration, there is a stretch-out in the current-voltage characteristic because the bias is applied across two different devices. Changing the polarity is equivalent to the process of write and erase of complementary resistive switching devices in crossbar arrays. In the case of anti-parallel configuration, the resistance window between both resistivity states is reduced. The control of the switching polarity has also been observed when applying a small ac signal, and measuring the conductance of the structures.Ministerio de Economía, Industria y Competitividad - FEDER (project TEC2017-84321-C4-2-R

EFFICIENT POSTAL SERVICE AND RESPECTFUL WITH THE ENVIRONMENT

[EN] The postal service is suffering an adaptation to the new markets opened by the users. The traditional post, letters and postcards, is being used less and is substituted by mail and packaging. To adequate to this new market it's important for the postal sector companies. In Spain, the operator of the Universal Postal Service has taken example from other companies of the sector, national and international, implanting electrical bicycle mail and packaging service in the centre of big cities. This is due to the fact that there are more the cities that are forbidding vehicle access to it's historical centres and the volume of packaging to deliver is greater. But, is it viable to deliver using hybrid and electrical vehicles in cities? This study intends to improve the distribution in cities with the implantation of these vehicles. It takes into account the characteristics of populations between 50.000 and 100.000 inhabitants, in which it will be analysed the advantages and inconvenience, doing special emphasis in the economic cost, conducting studies of the costs of implantation and amortization time.Vera López, J.; Pabón Dueñas, AB.; Liñán Ruiz, RJ.; Merino Córdoba, S. (2016). EFFICIENT POSTAL SERVICE AND RESPECTFUL WITH THE ENVIRONMENT. En XII Congreso de ingeniería del transporte. 7, 8 y 9 de Junio, Valencia (España). Editorial Universitat Politècnica de València. 1965-1974. https://doi.org/10.4995/CIT2016.2015.4085OCS1965197