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The object of research is the process of forming a mathematical model (MM) for calculating accuracy at the stages of construction an analytical standard (AS) using the chain method, the application of which is shown on the example of an aviation object (AO). The analysis of the investigated AO, namely the helicopter stabilizer, was carried out using modern 3D scanners and the creation of its analytical portrait (AP). The problem is to create the most similar AP and compare it with AS, taking into account the results of the calculations. The following results were obtained: the AS was built and the AP of the stabilizer geometry was created, a comparative analysis of the AP and AS was carried out, and the results of the accuracy of the object geometry calculations were obtained. Aerodynamic calculations of stabilizer characteristics were also carried out, analysis of standardized aerodynamic profiles was carried out taking into account the accepted limitations for forming the stabilizer AS. The scientific and practical novelty of the obtained results is as follows: the created MM for calculating the accuracy of the dimensions of the unit contour using the chain method made it possible to estimate the tying errors that occur when using the loft-template method. This made it possible to choose equipment and software for construction the AS stabilizer. The selection of improved values of the object’s aerodynamic characteristics made it possible to build an AS based on the standardized NACA 0012 profile. This can be used as an information basis for the organization of smallscale production of the object under study. That is, in general, the process of reverse engineering made it possible to conduct a detailed analysis of sections, aerodynamic characteristics and improve them for the future improved profile. This design approach provides wider opportunities, eliminates intermediate links and maintains high accuracy of object parameters during its manufacture, which is one of the main requirements in aircraft construction [ABSTRACT FROM AUTHOR]

The object of research is the process of forming a mathematical model (MM) for calculating accuracy at the stages of construction an analytical standard (AS) using the chain method, the application of which is shown on the example of an aviation object (AO). The analysis of the investigated AO, namely the helicopter stabilizer, was carried out using modern 3D scanners and the creation of its analytical portrait (AP). The problem is to create the most similar AP and compare it with AS, taking into account the results of the calculations. The following results were obtained: the AS was built and the AP of the stabilizer geometry was created, a comparative analysis of the AP and AS was carried out, and the results of the accuracy of the object geometry calculations were obtained. Aerodynamic calculations of stabilizer characteristics were also carried out, analysis of standardized aerodynamic profiles was carried out taking into account the accepted limitations for forming the stabilizer AS. The scientific and practical novelty of the obtained results is as follows: the created MM for calculating the accuracy of the dimensions of the unit contour using the chain method made it possible to estimate the tying errors that occur when using the loft-template method. This made it possible to choose equipment and software for construction the AS stabilizer. The selection of improved values of the object’s aerodynamic characteristics made it possible to build an AS based on the standardized NACA 0012 profile. This can be used as an information basis for the organization of small scale production of the object under study. That is, in general, the process of reverse engineering made it possible to conduct a detailed analysis of sections, aerodynamic characteristics and improve them for the future improved profile. This design approach provides wider opportunities, eliminates intermediate links and maintains high accuracy of object parameters during its manufacture, which is one of the main requirements in aircraft construction. [ABSTRACT FROM AUTHOR]

Highlights: [•] The presence of a line of tall vehicles in the bridge aeroelastic behavior is investigated. [•] The used CFD techniques reproduced 2D vortex-induced bridge oscillations. [•] The presence of a line of tall vehicles increases amplitude of oscillations. [•] The presence of vehicles does not significantly change the critical wind velocity. [Copyright &y& Elsevier]

[Display omitted] • Dry powder inhalers were developed for drug the delivery using nanotechnology. • Nanoparticles were synthesized using hyaluronic acid along with chitosan. • Also, hyaluronic acid was used with chitosan derivatives to prepare nanoparticles. • Spray-drying and freeze-drying were used as drying techniques to obtain nanopowders. • Stochastic lung model exhibited particle deposition in the lungs. • Drying techniques show small changes in sample profiles upon characterization. Dry powder inhalers (DPIs) are already on market, however, none of the DPIs are present for the treatment of tuberculosis. Herein, isoniazid-loaded nanopowders were developed for the delivery to the deeper lung tissues, more precisely alveoli. Chitosan (CS), thiolated chitosan (TC), and mannosylated chitosan (MC) were used individually in conjugation with hyaluronic acid (HA) because of their affinity for the pulmonary epithelium and alveolar macrophages. Here, the densities, Carr's index, fine particle fraction (FPF), mass median aerodynamic diameter (MMAD), and in-silico behavior were examined by employing two drying techniques (freeze-drying and spray-drying) for nanopowders. During a preliminary evaluation, no significant difference was observed in the aerodynamic and in-silico profiles of the nanopowders produced by either drying technique. Nanopowders posed no toxicity to A549 cells as demonstrated by the MTT assay. Overall, the particle deposition profile was found to be promising for all the freeze-dried samples and spray-dried samples containing mannitol. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of sound pressure levels through theoretical modeling and experimental validation in a 1 kW small wind turbine. The models used in the theoretical analysis are BPM (Brooks, Pope, and Marcolini) and BM (Brooks and Marcolini), where wind turbine blades are divided in sections, and each section has its own contribution with respect to the total emitted sound pressure level. The noise propagation study and its experimental validation were accomplished within the requirements of the standard IEC 61400-11 Ed.3 and the standard NOM-081-SEMARNAT-1994. The comparative study of theoretical and experimental results showed that the BPM and BM methods have a maximum error of 5.5% corresponding to the rated wind speed of 10 m/s. However, at low wind speeds, the theoretical models fit well to experimental data, for example, in the range from 5 to 8 m/s. The experimental data showed that the rotor's aerodynamic noise is more evident at low wind speed, because under these conditions, environmental noise is much less than wind turbine noise. Finally, to prevent possible negative effects on people's health, there is a recommended minimum and suitable distance between small wind turbine installations and buildings. [ABSTRACT FROM AUTHOR]