Recent progress in aircraft smart skin for structural health monitoring

Through the integration of advanced sensors, actuators, and micro-processors, aircraft smart skin technology can improve the structural performance of aircraft and make them self-perception, self-diagnosis, self-adaptation, self-learning, and self-repair. Aircraft smart skin for structural health monitoring (SHM) is an important type of aircraft smart skin and has received extensive attention in recent years. Large-scale, lightweight, and low-power consumption are three key problems hindering the realization and engineering applications of aircraft smart skin for SHM. In view of these problems and restrictions of practical aircraft onboard applications, this article reviews the current research progress on aircraft smart skin for SHM, introduces their design, materials, manufacturing process, and monitoring principles in detail, and discusses how they study above problems from these aspects. Finally, perspectives are proposed on the opportunities and future developments of aircraft smart skin for SHM.

High-Performance Power Converter for Charging Electric Vehicles

This paper presents the analysis, modeling, simulation and practical studies of resonant inverters with a voltage limitation on the resonant capacitor. The power circuits obtained in this way are characterized by the fact that the power consumption does not depend on the load changes, but is a function of the operating frequency, the value of the resonant capacitor and the supply voltage—these are the so-called inverters with energy dosing. Analytical dependences, simulations and experimental results were determined, which described the behavior of the studied power electronic devices. The obtained expressions for the inverter current in the different stages of the converter operation were the basis for the creation of the engineering methodology for their design and prototyping. Based on the derived basic ratios and characteristics, the capabilities of these devices for self-adaptation to the needs and changes of the load were demonstrated. A comparison of the characteristics of classical resonant inverters and those with energy dosing was made, thus demonstrating their qualities and advantages. The presented results display the properties of this class of circuits and the challenges to their effective application to find the optimal solution for the implementation of charging stations for different specific needs. On the other hand, the limitations in the use of these circuits were that no power was consumed from the power supply during the whole period, the lack of limitation of the maximum current through the transistors and the need for sufficient time to dissipate energy in the resonant inductor when working with high-resistance and low-power loads.

Measuring happiness under interpersonal comparison: An advanced theoretical framework and implications

The origin of happiness arouses people’s curiosity for a long time. Recent research introduces a utility theory for measuring subjective happiness in a social context. The past recent monetary conditions influence the present subjective happiness through two distinct channels: interpersonal comparison and self-adaptation. In this paper, we develop this theory to analyze behavioral patterns. Together with prospect theory’s gain-loss utility function, we exploit the theory in predicting psychological phenomena of craving. We explore the relationships between happiness and earnings. Under certain conditions, a high payoff disappoints you immediately and even leads to continuous disappointment across periods. We extend the explanations of the scenarios of New York cabdrivers’ labor-supply decisions. The effect of social comparisons may trigger workers’ behaviors of quit-working, which deepen related understandings of the literature.

Bacterial Microbiomes in the Sediments of Lotic Systems Ecologic Drivers and Role: A Case Study from the Mureş River, Transylvania, Romania

Numerous sections of the Mureş River vary in terms of the abundance of nitrates, ammonia, and orthophosphates; and of correlated lotic sediment bacterial microbiome structures in terms of both diversity and abundance. This highlights the great versatility of microbiomes in being influenced by the physical-chemical characteristics of environments and their spatial changes. Bacteria microbiomes exhibit dynamic and shifting potential and significant tendencies toward self-organization and self-adaptation. These typical features represent an essential ecologic basis for lotic systems having to do with the use and reuse of various kinds of environmental resource as chemical substances. In this respect, trophic processes assure the river ecosystem optimum health ecologic status dynamic and trend, to be reached. The flexibility of shifting bacterial microbiomes is crucial in maintaining this ecological context’s vital role in biogeochemically sustaining other taxonomic groups, which are spatially and temporally continuous. This is especially important for nutrient cycle processes, even for rivers with high levels of negative human impact, in promoting a functional lotic system.