Conceptual foundations for social media in the restaurant business in the aftermath of the pandemic

The article examines the key problems, changes and restrictions in the development of the restaurant business during the coronavirus pandemic. The analysis of the results of a study by European scientists on the use of social networks in the restaurant business is carried out. The essence of social media marketing (SMM) as an effective tool for overcoming the temporary crisis of the restaurant business is characterized. The target market was segmented and the results analyzed. The analysis shows the target market breakdown of restaurant visitors by marital status and by age groups. The main reasons why restaurateurs do not plan to use social networks or have not yet initiated the use of social networks are considered. The study identified the impact of the coronavirus pandemic on the restaurant business and presented ways to overcome them. The importance of marketing use in social networks by restaurateurs is justified. Based on the results of the study, the main conclusions are presented on the feasibility of introducing certain measures in the restaurant business to stabilize the financial situation, overcome the crisis and recoup the maximum production costs

Impact of pandemic on supply chain development

This article reveals the main aspects of the logistics situation development in the conditions of the COVID-19 pandemic, in particular, it highlights the main elements of the logistics companies functioning ensuring a competitive position in the market. The priority role of statistical data collection in logistics and verification of its development monitoring with high growth and expanded coverage of forecast indicators without taking into account the pandemic statistics is emphasized. At the same time, the main aspects of supply chain recovery, taking into account the pandemic, were identified and highlighted in such interrelations as identified signs, stocks, realistic consumption by efficient users, optimization of production and computing capacities, identification and use of logistics capacities, cash management and net working capital

The prediction of urinary calculi fragmentation duration under the holmium laser pulses

The results of settlement-experimental definition (prediction) of urinary stones fragmentation duration by the holmium laser impulses with the wavelength of 2.1 microns and energy from 0.8 to 1.6 J are presented in the paper. The obtained analytical expressions allow to estimate the duration of urinary stone complete fraction on the basis of its volume and radiological density as well as on its location, comprising the auxiliary manipulations time, and to predict lithotripsy operation duration regarding this data

Methods of Generating Key Sequences Based on Parameters of Handwritten Passwords and Signatures

The modern encryption methods are reliable if strong keys (passwords) are used, but the human factor issue cannot be solved by cryptographic methods. The best variant is binding all authenticators (passwords, encryption keys, and others) to the identities. When a user is authenticated by biometrical characteristics, the problem of protecting a biometrical template stored on a remote server becomes a concern. The paper proposes several methods of generating keys (passwords) by means of the fuzzy extractors method based on signature parameters without storing templates in an open way

Conceptual Design and Control Schedule Optimization for Parallel Hybrid Propulsion System of Regional Turboprop Aircraft

Current environmental policies for the aviation industry motivate the use of cleaner propulsion systems to reduce its CO2 and noise footprint in the coming years. In this context, hybrid propulsion systems have emerged as a potential solution as they have demonstrated a good trade-off between performance and low pollutant emissions. In the present work, the conceptual design and control schedule optimisation of a parallel hybrid propulsion system for the De Havilland Dash 8 regional turboprop aircraft is carried out. A parametric study of the turboprop engine with different degrees of hybridisation at design point and off-design performance analysis of the parallel hybrid propulsion system with different control schedules for an aircraft typical mission has been carried out. Overall aircraft performance parameters are used to evaluate hybrid propulsion systems with different degrees of hybridisation and control schedules. From the results, it was found that a control schedule with 10-15% hybridisation during the cruise phase is the most promising when considering the aircraft mission blocked fuel and fuel efficiency

Water-in-Oil Emulsions Separation Using a Controlled Multi-Frequency Acoustic Field at an Operating Facility

Separation of water-in-oil emulsion is a significant part of the cost of oil production due to the use of expensive demulsifiers and additional heating of the emulsion by burning associated petroleum gas. The article discusses an acoustic method that enables the increasing of the rate of separation of the emulsion. In field conditions, tests were carried out in which the efficiency of separation in the acoustic field was determined depending on the temperature of the product, the concentration of the demulsifier, and the frequency and time of exposure to the emitter. The results obtained allow us to talk about a significant reduction in the consumption of demulsifiers, a decrease in the influence of temperature on the phase separation process and an increase in the efficiency of oil treatment at existing facilities

Water-in-Oil Emulsions Separation Using a Controlled Multi-Frequency Acoustic Field at an Operating Facility

Separation of water-in-oil emulsion is a significant part of the cost of oil production due to the use of expensive demulsifiers and additional heating of the emulsion by burning associated petroleum gas. The article discusses an acoustic method that enables the increasing of the rate of separation of the emulsion. In field conditions, tests were carried out in which the efficiency of separation in the acoustic field was determined depending on the temperature of the product, the concentration of the demulsifier, and the frequency and time of exposure to the emitter. The results obtained allow us to talk about a significant reduction in the consumption of demulsifiers, a decrease in the influence of temperature on the phase separation process and an increase in the efficiency of oil treatment at existing facilities

Luminescent Properties of Zn and Mg Complexes on N-(2-Carboxyphenyl)salicylidenimine Basis

New zinc and magnesium complexes of N-(2-carboxyphenyl)salicylidenimine) were synthesized and structurally characterized by elemental analysis, FT-IR, and X-ray single-crystal analysis. These complexes exhibit tuneable luminescence in the solid state from blue to green by varying by metal ion and composition. Moreover, the quantum yields range from 0.11 to 0.41, while lifetimes were determined to be in the nanosecond timescale. Thermal analysis shows that these complexes exhibit good thermal stability and can therefore well be used as electroluminescent materials

Tetranuclear Lanthanide Complexes Containing a Hydrazone-type Ligand. Dysprosium [2 × 2] Gridlike Single-Molecule Magnet and Toroic

A multidentate hydrazone-type ligand (<i>Z</i>,<i>Z</i>)-bis­(1-(pyridin-2-yl)-1-amino-methylidene)­oxalohydrazide (H₂L) was utilized in the synthesis of three new isomorphous tetranuclear complexes of the general formula [Ln₄(HL)₄(H₂L)₂­(NO₃)₄]­(NO₃)₄·4CH₃OH (Ln = Gd^III, <b>1</b>, Tb^III, <b>2</b>, Dy^III, <b>3</b>) with the gridlike [2 × 2] topology. The analysis of the static magnetic data revealed weak anti-ferromagnetic interaction among lanthanide­(III) atoms, whereas dynamic magnetic data led to the observation of the single-molecule magnet behavior in zero static magnetic field for the Dy₄ compound <b>3</b> with <i>U</i>_eff = 42.6 K and τ₀ = 1.50 × 10^–5 s. The theoretical CASSCF calculations supported also the presence of the net toroidal magnetic moment, which classifies compound <b>3</b> also as a single-molecule toroic