A Control Solution for a Tethered Kite Trajectory Tracking With Application to Ship Propulsion

In the field of clean and green energy production systems, airborne wind energy (AWE) systems are really promising technologies. Replacing lightweight tethers with expensive towers, is an innovative solution to get energy from higher altitudes than classical wind turbines. But AWE systems can also be used to produce a traction force through a fast-flying airfoil, or kite. In this paper, the traction force is supposed to be used for ship propulsion. Such an application is permitted if the kite is kept on an appropriate trajectory. This paper thus considers the design of an automatic pilot for trajectory tracking. Its design requires a path-planning and a control strategies that are described here. In terms of control strategy, a robust CRONE controller is designed based on a family of linear models that stands for the nonlinear model of the kite and obtained numerically around several trajectories and for various flight conditions. Efficient trajectories for ship traction being periodic, a method involving tools dedicated to time-varying periodic systems is then used to validate the approach used for CRONE controller design.

What should be the goal of public policies?

Should subjective wellbeing, as measured by life evaluation, be the sole criterion for policies? This article answers this question negatively based on three arguments. First, it is important to distinguish between people's life evaluations, their emotional experiences and their sense of purpose; each has different drivers and consequences, implying that no single measure can adequately subsume the others. Second, while subjective wellbeing provides information missed by more conventional measures, the reverse is also true. This implies that information on the intrinsic importance of other key wellbeing dimensions cannot be derived from just looking at their instrumental value in raising subjective wellbeing. Third, the ‘utilitarian calculus’ implicit in subjective wellbeing regressions shines little light on normative decisions such as the attention we should focus on the worst off or on future generations. In contrast to the ‘automatic pilot’ approach to policies advocated by Frijters et al., this article favours an approach based on dashboards of indicators used to inform all of the stages of the policy cycles, as recently implemented by several OECD countries.

Research on Influencing Factor Selection of Pilot’s Intention

The physiological, psychological, and physical characteristics of the pilot will have an impact on flight safety, mainly in the pilot’s intention. In another word, this means the pilot’s psychological experience of flight status under the influence of various factors and the preference for decision-making or behavioral value that is displayed. The pilot’s intention is to reflect the cognitive state that the pilot showed during the maneuvering of the aircraft. The exploration of intention is very important for the study of automatic pilot and flight control active safety system. Also, it is an important concept often involved in the study of human factors in flight, especially the microbehavior of pilots. Pilot’s intention is taken as the study object in this paper; physiological-psychological-physical parameters are obtained through analyzing their influencing factors from the simulating flight experiments designed. The random forest analysis method is used to rank the main influencing factors affecting the pilot’s intention, and the factor sequence is formed. The results provide a good foundation for further research on the pilot’s intention identification.

Rumination and Mindlessness Processes: Trajectories of Change in a 42-Day Mindfulness-Based Intervention

This preliminary study aimed to understand the effects of an autonomous mindfulness-based intervention (MBI) on mindlessness propensities: rumination, automatic pilot functioning, and attentional distractibility. The ecological momentary assessment was completed by community participants assigned to two nonrandomized groups: an experimental group (n = 45) that practiced 20-minute daily mindfulness meditation for 42 days and a control group (n = 44) that was on the waiting list for the MBI. All participants completed a self-assessment on rumination and mindlessness propensities twice a day. The MBI led to a favorable gradual decrease in automatic pilot functioning and attentional distractibility. Rumination evolved in three stages: a rapid decrease during the first week, a stabilization phase between the 10th and 30th days, and an additional decrease after 30 days of practice. This innovative study provides a promising perspective regarding rumination, automatic pilot functioning, and attentional distractibility dynamic trajectories over the course of an MBI.