X-Rays from long laboratory sparks in air

This collective book provides a review of research concentrated on runaway electron beams and X-rays in an inhomogeneous electric field with different gases at increased pressure. Attention is also given to supershort avalanche electron beam (SAEB) in the optimal conditions. New experimental techniques and equipment, including those with picosecond time resolutions, were required for diagnostics of electrical and optical signals. The book consists of twenty-four chapters, some of which were written jointly by researchers of different teams. Some chapters consider the range of SAEB applications.Postprint (published version

Overview of lightning interaction and damages to wind turbines

It is well known that tall structures such as telecommunication towers can be exposed to numerous lightning incidence. Wind turbines are in this group, but two particular characteristics distinguish wind turbines from the rest. The first peculiarity is that a substantial part of the structure is rotating. That corresponds to the rotor blades. The second, is also related to the rotor blades and corresponds to the intensive use of composite materials. Due to these two factors, protection against lightning requests very special attention.Postprint (author's final draft

Understanding lightning leaders

a lightning flash is defined by the initiation and multiple development of leaders. But lightning leaders are still poorly understood. Since most of my atmospheric electricity has been focused on lightning that means that it has been devoted to understand lightning leaders. In this work, I summarize my investigations related to different aspects of lightning leaders. That includes high-speed video observations of lightning leaders, investigations of bidirectional development of leaders by means of radio mapping systems, research on the high energy emissions produced by lightning leaders and the study of upward leader initiation from wind turbines and development. In the second part, the need of an improved lightning leader model is exposed and proposed as future work. Lightning leader models can be approached by different ways depending on the purpose but agreement between all the approaches is still not complete.Postprint (published version

Lightning interaction and damages to wind turbines

Multi-megawatt wind turbines are a special type of tall structures. Two characteristics stand out from other tall objects such as buildings and telecommunication towers. The first particularity is that a large part of the structure is rotating, and the second, is the extensive use of composite materials in the rotor blades. Due to these two factors, the protection against lightning requests very special attention. Wind turbines installed all over the world have shown how a particular design of their lightning protection system (LPS) can perform very different in areas with different thunderstorm climatology. Up to now, the most severe damages are reported in those areas affected by winter thunderstorms such as Japan and Europe (e.g. Honjo, 2015). These type of storms pose the most favorable conditions for upward lightning initiation from tall structures. That is because the heights of charge regions of winter thunderstorms are significantly low (e.g. Montanyà et al., 2007). On the other hand, most wind turbine blades are built wind composite materials such as glass fibers (GF) and carbon reinforced plastics (CFRP). Blades are typically composed of two shells enclosing a spar. The lighting protection system consists of one or several air terminals connected to a down conductor that brings lightning currents to ground (e.g. IEC 61400-24, 2010). However, the insulation provided by the shells is not perfect and it is possible to experience lightning attachments to non-desired locations. Some blades are equipped with electrically conductive carbon fiber reinforced plastics (CFRP), these components shall be bonded to the lightning protection system (IEC 61400-24, 2010). CFRP laminates are poor conductive presenting high anisotropy. Moreover, electrical connections to CFRP can be very complex because in most of the cases it is not possible to use bolted connections. In the first part of this work lightning interactions to wind turbines are described according to the types of thunderstorms. The effects of the different type of interactions to the calculation of risk assessment is discussed. In the second part, lightning damages are treated. This include a review of the mechanisms of damages and statistics. The case of incidences to blades and protection to CFRP components are highlighted.Postprint (published version

Empowerment in the Public Sector: Testing the Influence of Goal Orientation

Empowerment has emerged as an important new issue in the public sector organization setting in the wake of mainstream new public management (NPM). Nevertheless, few studies in this frame have combined structural (managerial) and psychological (individual) approaches in an integrative study of empowerment. There is also a need to examine the moderating variables involved in this relationship, as well as to extend research on work motivation in public management. This study explores the effect of structural empowerment on psychological empowerment, and it also draws on goal orientation (GO) theory to examine the moderating role of employees’ GO in this link. The model is tested on a sample of 521 Spanish local authority employees. The results do not confirm the direct link between structural and psychological empowerment, but show that learning GO has considerable moderating power in this relationship, and its interaction with structural empowerment affects employees’ psychological empowerment levels

Reliability-based economic model predictive control for generalized flow-based networks including actuators' health-aware capabilities

This paper proposes a reliability-based economic model predictive control (MPC) strategy for the management of generalized flow-based networks, integrating some ideas on network service reliability, dynamic safety stock planning, and degradation of equipment health. The proposed strategy is based on a single-layer economic optimisation problem with dynamic constraints, which includes two enhancements with respect to existing approaches. The first enhancement considers chance-constraint programming to compute an optimal inventory replenishment policy based on a desired risk acceptability level, leading to dynamically allocate safety stocks in flow-based networks to satisfy non-stationary flow demands. The second enhancement computes a smart distribution of the control effort and maximises actuators’ availability by estimating their degradation and reliability. The proposed approach is illustrated with an application of water transport networks using the Barcelona network as the considered case study.Peer ReviewedPostprint (author's final draft

The circadian typology is related to differences in emotional intelligence

This study examines the relationships between circadian typology and emotional intelligence taking into account the possible interactions between sex and physical exercise, and controlling for age. A sample of 1011 participants (649 women; 26.92 ± 6.53 yr) completed the reduced Morningness-Eveningness Questionnaire and the Trait Meta-Mood Scale-24. Women showed higher emotional attention scores, while men showed higher emotional repair scores (p< .035). Subjects who do physical exercise weekly showed higher emotional repair scores (p=.001). Morning-type had lower emotional attention than evening and neither-type; neither-type exhibited lower emotional repair than morning-type, and lower emotional clarity than both evening and morning-type (p<.046). Circadian typology modulated sex differences in emotional attention, only morning-type group men showed lower emotional attention scores than women. Morning typology may be a protective factor in terms of general health, while we should be aware that the neither-type may present a vulnerability to develop psychological problemsCTS-19

Report on argumentation and teacher education in Europe

This document will ultimately form part of a comprehensive package of materials for teacher education and professional development in argumentation. The initial deliverable from Kaunas University of Technology described the rhetorical basis of argumentation theory for pre‐ and in‐service teachers, whilst this state of the art report sets out the current and rather unsatisfactory status of argumentation in curricula, initial teacher training/education and teacher professional development, across the fifteen S‐TEAM partner countries. We believe that this is a representative sample and that the report can be taken as a reliable snapshot of the situation in Europe generally

Electromagnetic radiation of simulated mid-gap streamers

Electromagnetic field from simulated double-headed mid-gap streamers is computed. The effect of the applied electric field is studied by considering electric fields higher than the conventional breakdown threshold (‘overvoltage’). The obtained results show a 20 dB decay at 3.8 GHz for conventional breakdown electric field, 35 GHz for ambient electric fields five times the conventional breakdown and 170 GHz for fields ten times the conventional breakdown electric field. The limitation in nature of the intense electric fields suggest further experiments using a radio receiver at frequencies of more than 10 GHz in order to investigate the origin of the detected x-rays in laboratory sparks.Preprin