Assessment of the worthwhileness of efficient driving in railway systems with high-receptivity power supplies

Eco-driving is one of the most important strategies for significantly reducing the energy consumption of railways with low investments. It consists of designing a way of driving a train to fulfil a target running time, consuming the minimum amount of energy. Most eco-driving energy savings come from the substitution of some braking periods with coasting periods. Nowadays, modern trains can use regenerative braking to recover the kinetic energy during deceleration phases. Therefore, if the receptivity of the railway system to regenerate energy is high, a question arises: is it worth designing eco-driving speed profiles? This paper assesses the energy benefits that eco-driving can provide in different scenarios to answer this question. Eco-driving is obtained by means of a multi-objective particle swarm optimization algorithm, combined with a detailed train simulator, to obtain realistic results. Eco-driving speed profiles are compared with a standard driving that performs the same running time. Real data from Spanish high-speed lines have been used to analyze the results in two case studies. Stretches fed by 1 × 25 kV and 2 × 25 kV AC power supply systems have been considered, as they present high receptivity to regenerate energy. Furthermore, the variations of the two most important factors that affect the regenerative energy usage have been studied: train motors efficiency ratio and catenary resistance. Results indicate that the greater the catenary resistance, the more advantageous eco-driving is. Similarly, the lower the motor efficiency, the greater the energy savings provided by efficient driving. Despite the differences observed in energy savings, the main conclusion is that eco-driving always provides significant energy savings, even in the case of the most receptive power supply network. Therefore, this paper has demonstrated that efforts in improving regenerated energy usage must not neglect the role of eco-driving in railway efficiency

El paisaje de la casa Wolf de Mies van der Rohe: Modulaciones, traslaciones y espacios

The making the draw up of the Wolf house (1925-27) by Mies van der Rohe; today destructed and converted part of the site in public park, allow a reflection about the set the the house in the plot through espaces, runs and limits. Elements used by Mies in the settlement. This work by Mies anticipates the avant-garde work made years late. Schinkel´s loggia/belvedere concept undergoes many transformations by Mies before achieves its most condensed expression. The interwoven theme of court house versus belvedere begins in the Wolf house, using the tectonic brick work as medium to make landscape around the house

Simultaneous analysis of elastic scattering and transfer/breakup channels for the 6He+208Pb reaction at energies near the Coulomb barrier

The elastic and alpha-production channels for the 6He+208Pb reaction are investigated at energies around the Coulomb barrier (E_{lab}=14, 16, 18, 22, and 27 MeV). The effect of the two-neutron transfer channels on the elastic scattering has been studied within the Coupled-Reaction-Channels (CRC) method. We find that the explicit inclusion of these channels allows a simultaneous description of the elastic data and the inclusive alpha cross sections at backward angles. Three-body Continuum-Discretized Coupled-Channels (CDCC) calculations are found to reproduce the elastic data, but not the transfer/breakup data. The trivially-equivalent local polarization potential (TELP) derived from the CRC and CDCC calculations are found to explain the features found in previous phenomenological optical model calculations for this system.Comment: 7 pages, 6 figures (replaced with updated version

Magnetic transitions in Pr2NiO4 single crystal

The magnetic properties of a stoichiometric Pr2NiO4 single crystal have been examined by means of the temperature dependence of the complex ac susceptibility and the isothermal magnetization in fields up to 200 kOe at T=4.2 K. Three separate phases have been identified and their anisotropic character has been analyzed. A collinear antiferromagnetic phase appears first between TN = 325 K and Tc1 = 115 K, where the Pr ions are polarized by an internal magnetic field. At Tc1 a first modification of the magnetic structure occurs in parallel with a structural phase transition (Bmab to P42/ncm). This magnetic transition has a first‐order character and involves both the out‐of‐plane and the in‐plane spin components (magnetic modes gx and gxcyfz, respectively). A second magnetic transition having also a first‐order character is also clearly identified at Tc2 = 90 K which corresponds to a spin reorientation process (gxcyfz to cxgyaz magnetic modes). It should be noted as well that the out‐of‐phase component of χac shows a peak around 30 K which reflects the coexistence of both magnetic configurations in a wide temperature interval. Finally, two field‐induced transitions have been observed at 4.2 K when the field is directed along the c axis. We propose that the high‐field anomaly arises from a metamagnetic transition of the weak ferromagnetic component, similarly to La2CuO4

Impact of the Intensive Program of Emotional Intelligence (IPEI) on middle man-agers’ emotional intelligence

Background: This study aimed to evaluate the effect of the Intensive Program of Emo-tional Intelligence (IPEI; Fernández, 2015) on middle managers’ emotional intelligence, as this variable may have a significant impact on personal satisfaction, task performance, and work environment. Method: The intervention was applied on work team supervisors from a big call center, as it is an overlooked sector in this topic. Two-hundred and eighty-two supervisors from a Spanish multinational Madrid-based company (51.4% males and 48.6% females) participated in this study. Participants were assigned to the experimental group (n = 190) or the control group (n = 92) by availability, according to management decision. All supervisors filled in two questionnaires to evaluate the differ-ent components of intrapersonal emotional intelligence (i.e., attention, clarity, and repair; TMMS-24; Fernández-Berrocal, Extremera, & Ramos, 2004) and cognitive and affec-tive empathy (i.e., perspective taking, emotion understanding, empathic joy, and person-al distress; TECA; López-Pérez, Fernández, & Abad, 2008). Results: The findings showed an increase in the studied variables for the experimental group. Conclusions: The obtained results support middle managers’ training on emotional competences through short, efficient, and economic programs, and it was discussed potential limita-tions and implications of the obtained results

A semiotic reflection on the didactics of the Chain rule

According to (Fried, 2008), there is an intrinsic tension in trying to apply the history of mathematics to its didactics. Besides the widespread feeling that the introduction of didactic elements taken from the history of mathematics can detract the pedagogy of mathematics from the attainment of important goals, (Fried, 2008, p. 193) describes a pair of specific pitfalls that can arise in implementing such historical applications in mathematics education. The description in (Fried, 2008), is presented in the parlance of Sausserian Semiotics and identifies two semiotic “deformations” that arise when one fails to observe that the pairing between signs and meanings in a given synchronic “cross-section” associated with the development of mathematics need not hold for another synchronic cross section at a different time. In this exposition, an example related to an application of the history of the chain rule to the didactics of calculus is presented. Our example illustrates the semiotic deformations alluded by (Fried, 2008), and points out a possible explanation of how this may lead to unrealistic pedagogical expectations for student performance. Finally, an argument is presented for the creation of a framework for a historical heuristics for mathematics education, possibly beyond the bounds of semiotics