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The present paper deals with weapon aerodynamics and aims to describe preliminary studies that were conducted for developing the next generation of long-range guided ammunition. Over history, ballistic research scientists were constantly investigating new artillery systems capable of overcoming limitations of range, accuracy and manoeuvrability. While futuristic technologies are increasingly under development, numerous issues concerning current powdered systems still need to be addressed. In this context, the present work deals with the design and the optimization of a new concept of long-range projectile with regard to multidisciplinary fields, including flight scenario, steering strategy, mechanical actuators or size of payload.

Investigations are conducted for configurations that combine existing full calibre 155 mm guided artillery shell with a set of lifting surfaces. As the capability of the ammunition highly depends on lifting surfaces in terms of number, shape or position, a parametric study has to be conducted for determining the best aerodynamic architecture. To speed-up this process, initial estimations are conducted thanks to low computational cost methods suitable for preliminary design requirements, in terms of time, accuracy and flexibility. The WASP code (Wing-Aerodynamic-eStimation-for-Projectiles) has been developed for rapidly predicting aerodynamic coefficients (static and dynamic) of a set of lifting surfaces fitted on a projectile fuselage, as a function of geometry and flight conditions, up to transonic velocities.

In the present study, WASP predictions at Mach 0.7 of both normal force and pitching moment coefficients are assessed for two configurations.

Analysis is conducted by gathering results from WASP, computational-fluid-dynamics (CFD) simulations, wind-tunnel experiments and free-flight tests. Obtained results demonstrate the ability of WASP code to be used for preliminary design steps.

The study aims to analyze the different types of risks related to the use of technology and determine their positive or negative influence on teachers' motivation and behavioral intention to use digital tools.

The research is based on survey data from 200 teachers in the Romanian preuniversity education system. The data analysis followed a four-step approach, using a partial least squares structural equation modeling (PLS-SEM) model for hypothesized relationships among research concepts and a PLS prediction-oriented segmentation (POS) procedure.

This study showed that increased risk awareness influences both motivation and, consequently, the intention to adopt digital tools in the preuniversity education system.

The scope of research remains constrained with regard to the examined population, considering the substantial number of teachers within the preuniversity education system. Another limit lies in the basic classification of identified risk types.

School managers should design a strategy to increase the level of motivation for integrating digital tools in the educational process.

Little scholarly attention has been devoted to investigating the risks associated with digitalization in the preuniversity education system. In addition, no prior research has been conducted to assess the influence of risk perception on people's motivation and intention to use digital tools in preuniversity education.

Technological progress is a determining factor in the factors leading to economic and social well-being. Simultaneously, the development of a sustainable economy is based on the conservation of resources. In the energy sector, this fact can be corroborated with the reduction of energy consumption, thus increasing economic efficiency. On the one hand, improving energy efficiency contributes to increasing the quality of life, productivity, and, implicitly, the economy, but on the other hand, it leads to excess energy use – this behavioral change is known as rebound. The research estimates the rebound effect at the macroeconomic level for European countries in the period 2000–2019, referring the analysis to each country's gross domestic product (GDP) and energy consumption, as well as comparing the preaccession and postaccession periods of Romania in the EU space. The rebound effect is determined using multidimensional analysis methods, depending on the GDP of each country as well as the behavior of each in the use of energy resources in industry, agriculture, and services. Although the study results confirm the strong link between energy consumption and GDP at the level of each state, they did not show considerable changes between countries at the level of the two periods.