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Abstract— The size and complexity of deep neural networks used in AI applications continue to grow exponentially, significantly increasing energy consumption for training and inference by these models. We introduce an open-source package eco2AI to help data scientists and researchers to track the energy consumption and equivalent CO2 emissions of their models in a straightforward way. In eco2AI we focus on accurate tracking of energy consumption and regional CO2 emissions accounting. We encourage the research for community to search for new optimal Artificial Intelligence (AI) architectures with lower computational cost. The motivation also comes from the concept of AI-based greenhouse gases sequestrating cycle with both Sustainable AI and Green AI pathways. The code and documentation are hosted on Github under the Apache 2.0 license https://github.com/sb-ai-lab/Eco2AI.

Semiconductor lasers have developed rapidly with the steady growth of the global laser market. The use of semiconductor laser diodes is currently considered to be the most advanced option for achieving the optimal combination of efficiency, energy consumption, and cost parameters of high-power solid-state and fiber lasers. In this work, an approach for optical mode engineering in planar waveguides is investigated. The approach referred to as Coupled Large Optical Cavity (CLOC) is based on the resonant optical coupling between waveguides and allows the selection of high-order modes. The state-of-art of the CLOC operation is reviewed and discussed. We apply the CLOC concept in our waveguide design strategy. The results in both numerical simulation and experiment show that the CLOC approach can be considered a simple and cost-efficient solution for improving diode laser performance.

The marketing activity of a modern airline is quite diverse. Under the conditions of an oligopoly, airlines develop their business in competition for a passenger.In modern conditions in Russia, the use of dumping methods of the early 1990s is very ineffective. There are no weak airlines left on the long-distance air transportation market, and in regional markets large companies lose to small regional carriers due to the high cost of performing flights on large-capacity aircrafts of the airline’s fleet.Generally, non-price methods of competition come out on top. Flexible tariff policy, advertising, and high service in servicing passengers remain leading traditional methods of competing for a passenger.This article is devoted to the study of another marketing method for attracting passengers, or rather retaining passengers on the airline’s flights, which is development of bonus programs, frequent flyer programs. PJSC Russian Airlines (Aeroflot) was chosen as the object for the study. The subject of the research is the «Aeroflot Bonus» program.The objective of the study is to study the cost of the program. For research purposes, this is the value of the frequent flyer program point. The problem proposed to be solved is to determine the amount of expenses for implementation of the bonus program of frequent flyers. When solving the problem in its staging part, the assessment is not limited to direct costs associated with the costs of marketing efforts in the form of costs for organising a special advertising department, issuing bonus cards, software, and wages. The estimation refers also to indirect costs in the form of unreceived proceeds from free bonus tickets. Besides, a rough estimate has been made of the airline’s hidden costs due to an unpaid seat on the plane. The study conclusions indicate that hidden costs will be taken into account in calculating the cost of a flight and the bonus program has a right to exist.

The program and the methodology of the experiment and the results of the experiment have been developed. The experimental bench and metrological support have been created, liquid nitrogen (LN) has been considered as a model liquid. A database of heat and mass exchange process parameters (pressure, temperature) under the modes of tank inflation with helium gas up to 2 atm., given external thermal loading, pressure relief after reaching 4 atm. up to 1 atm. The technique of processing the results of pressure and temperature measurements with the assumptions and limitations is given.

Herein, we describe the synthesis of coordination compounds starting from carbohydrazide ((H2NHN)2C=O (CHZ)) and the Zn2+ salt of dinitramic acid (HDN), which are high-nitrogen substances that exhibit properties similar to those of a burning-rate inhibitor of pyrotechnic compositions. This study demonstrates that these compounds react with glyoxal to furnish adducts of metal–organic macrocyclic cages bearing the elements of carbohydrazide, complexing metals and the HDN anion, depending on the ratio of the starting reactants. The assembled macrocyclic cage has “host–guest” properties and is a safe container for the storage of HDN salts. X-ray crystallographic analysis of the resultant coordination compound, [Zn(chz)3(N(NO2)2)2]), indicated that the metal–ligand association occurs via the N and O atoms of carbohydrazide. The zinc salt of dinitramic acid, which is enclosed into adducts with a macrocycle, is thermally stable and insensitive to mechanical impacts. The complex zinc salt of dinitramide was shown herein to exhibit inhibitory activity towards the burning rate of pyrotechnic compositions.

Here, we report the study results of the nitration of 3,7,10-trioxo-2,4,6,8,9,11-hexaaza[3.3.3]propellane (THAP) by different nitrating agents such as nitric acid, mixed nitric/sulfuric acids, nitric anhydride, and mixed concentrated nitric acid/acetic anhydride to furnish 3,7,10-trioxo-2-nitro-2,4,6,8,9,11-hexaaza[3.3.3]propellane and 3,7,10-trioxo-2,8-dinitro-2,4,6,8,9,11-hexaaza[3.3.3]propellane, whereas a lactam–lactim rearrangement was found to take place upon vigorous cooling to give 10-hydroxy-2,4,6,8,9,11-hexaazatricyclo[3.3.3.01,5]undec-9-ene-3,7-dione. The two competing reactions, lactam–lactim rearrangement, and nitration were found to take place. The acylation of 3,7,10-trioxo-2,4,6,8,9,11-hexaaza[3.3.3]propellane was examined and the formation conditions of 2,6-di- and 2,6,9-triacetyl-substituted and 3,7,10-trioxo-2,4,6,8,9,11-hexaacetyl-2,4,6,8,9,11-hexaaza[3.3.3]propellane were established. The acetyl derivatives were found to be instable in an acidic medium and to undergo deacylation. The obtained findings correlate well with the quantum-chemical calculations.

Recently the reversible cellular automata are increasingly used to build high-performance cryptographic algorithms. The paper establishes a connection between the reversibility of homogeneous one-dimensional binary cellular automata of a finite size and the properties of a structure called binary filter with input memory and such finite automata properties as the prohibitions in automata output and loss of information. We show that finding the preimage for an arbitrary configuration of a one-dimensional cellular automaton of length L with a local transition function f is associated with reversibility of a binary filter with input memory. As a fact, the nonlinear filter with an input memory corresponding to our cellular automaton does not depend on the number of memory cells of the cellular automaton. The results obtained make it possible to reduce the complexity of solving massive enumeration problems related to the issues of reversibility of cellular automata. All the results obtained can be transferred to cellular automata with non-binary cell filling and to cellular automata of dimension greater than 1.

Dinitramic acid salts are promising components as oxidizers and burning-rate modifiers of high-energy compositions. However, most of these salts are not free of drawbacks such as hygroscopicity. Therefore, their application under special conditions of use and storage is limited. The synthesis and storage of stable dinitramic acid salts is a topical issue. Here, we synthesized an adduct starting from the nickel salt of dinitramic acid with carbohydrazide and glyoxal to settle the problem of stability and storage of that salt. The chemical composition of the adduct was confirmed by infrared spectroscopy and elemental analysis. The Ni content was determined by atomic emission spectroscopy. Thermogravimetric DSC and TGA analyses showed the adduct to have three decomposition stages. The adduct exhibits a good thermal stability and a low sensitivity to mechanical stimuli. Here, the adduct is demonstrated to be a promising burning-rate inhibitor of pyrotechnic compositions.

This paper presents the results of an experimental study of the formation of large-scale non-uniformity of liquid flow on a RSR metal random packing of 0.47 m in diameter and a Sulzer 500X structured packing of 0.6 m in diameter. The experiments on the RSR packing were carried out with water without vapor flow for the superficial velocity of the liquid varying as $$3\cdot 10^{-3}< L_{0}

Edge-emitting lasers with active regions based on novel InGaAs/GaAs quantum heterostructures of transitional dimensionality, i.e., quantum well-dots, which are intermediate in properties between quantum wells and quantum dots, are studied. It is shown that the rate of the lasing-wavelength blue shift decreases with increasing number of quantum well-dot layers in the active region and with increasing optical confinement factor as the cavity length decreases. In a laser with 10 quantum well-dot layers, the lasing-wavelength position remains within the limits of the fundamental optical transition down to the smallest cavity lengths (100 μm). In devices with a single quantum well-dot layer and/or with a low optical confinement factor, lasing directly switches from the ground state to waveguide states omitting excited states below ≤200 μm. Such an effect has not been observed in quantum-well- and quantum-dot lasers and can be attributed to the abnormally low density of excited states in quantum well-dots.

Analytical expressions are presented, and, through them, the analysis of component parts of the electrical resistance of injection microdisk lasers is carried out depending on the size of the microdisk resonator, parameters of the substrate, and configuration of the contact to it.

This paper presents experimental results on heat transfer efficiency on a flat circular heat-release surface modified using additive technology. A porous plate 500 $$\mu$$ m thick, 3D-printed from copper spherical granules with an average diameter of 50 $$\mu$$ m, was fixed by means of resistance soldering on a heat-release brass surface of 20 mm in diameter. The heat transfer was investigated at boiling in liquid Freon R21 under free convection conditions for the heat flux density varying from 200 to $$4.5\cdot 10^{5}$$ W/m2. In different series of the experiments, the reduced pressure varied within 0.027–0.064. The experiments have shown that under conditions of activated nucleation sites, the heat transfer coefficient for a modified surface 4–5 times exceeds that for an unmodified surface. The greatest effect is observed in the region of small and medium values of the heat flux density.

Methods for analyzing the economic activity of airlines and forecasting the prerequisites for bankruptcy of airlines is becoming an important task for development of the industry. In past years, there were examples of a sound negative experience related to bankruptcy of airlines. At the same time, the main volume indicators of the airlines concerned had got positive dynamics shortly before the bankruptcy and were considered by BCG matrix as evident «stars» in terms of growth in production volumes and in the share of the air transportation market. In Russia that was the case of Sibir airlines which in 2007–2008 barely avoided bankruptcy, as well as of Transaero Airlines that has left the air transportation market forever. The first lowcost airlines, Skyexpress and Avianova, went bankrupt amid high growth in the number of passengers transported. The task of the research was to create a model that allows to simulate the situation associated with the airline overcoming the so-called «second break-even point». To forecast the possible time period for the airline to receive an operating loss against the background of growing volume indicators, production and financial indicators of one of the leading Russian airlines were used. The method of research is modelling of volume and financial indicators of the airline activity. The model is proposed to be built not on the study of future changes in the growth of volume and financial indicators, but on the study of dynamics of the rate of change of those indicators. The study is based on the fact that the dynamics of air transportation has a cyclical basis, which is invisible when directly analyzing changes in production and financial indicators, and which is on the contrary clearly visible when studying the dynamics of the rates of those indicators, which makes it possible to simulate a situation when the airline will have an operational loss in the future.

In the work, a review of scientific articles on the behavior of tissues and organs of the human body under local mechanical effects on it, as well as a description of the physico-mechanical properties of biological materials. The selection of mechanical behavior for each biological material as part of a mathematical model of the human torso was carried out, its finite element model was created, validation experiments were modeled using data presented in the literature. An original calculation model of a human torso with a tuned interaction of organs with each other was developed. Contact interaction parameters are determined. The developed computational model of a human torso was verified based on data from open sources for an experiment with mechanical action by a cylindrical impactor. An algorithm for processing pressure and acceleration graphs has been implemented in order to obtain tolerance curves. A specialized modular program has been created for the automated processing of calculation results and the output of the main results. 42 numerical tests were carried out simulating the entry of a steel ball into each of 21 zones for power engineers of 40 and 80 J. According to the results of the tests for each organ, pressure and acceleration tolerance curves were obtained, animations of the behavior of organs under shock were created, visualization of the pressure field propagation in organs was obtained torso.

Analysis of demand for air transportation is a key business process around which each airline develops strategic and operational plans. Based on the demand forecast, strategic plans for development of the airline’s route network are developed, as well as budgeting, financial planning, sales and marketing plans, aircraft fleet planning, risk assessment and plans to overcome their consequences. Demand analysis also facilitates important management activities, such as decision-making, performance evaluation, and reasonable allocation of resources in specific and uncertain conditions for development of the air transport system. Based on the specific requirements of the airline or in relation to a specific airline, an individual demand forecasting model can be developed. Such a model is an extension or a combination of various qualitative and quantitative methods for forecasting demand. The task of developing a custom model is often iterative, highly detailed, and driven by expert knowledge and can be accomplished by introducing suitable demand management software. The task stated in the article is not a staging task for building a model, but only offers to study the available theoretical material for the analysis of demand for air transportation based on the most famous models for forecasting demand for transportation. The method of scientific research of the problem posed in the article is the method of scientific analysis of existing models. Offer and demand for air transport services are reciprocal but asymmetric. Although the realized demand for transportation cannot take place without an appropriate level of supply, an air transport service can exist without appropriate demand. This is often found in projects that are developed with a margin that meets the expected level of demand, which may or may not be realized, or it may take several years to be realized. Regular air transport services form a supply that exists even if demand is insufficient. Several models presented in the article emphasize the conditions in which there is supply saturation, and on the other hand, the models in which demand is formed due to the mutual attractiveness of the entities that form demand are considered.

High-speed photodetectors (PDs) based on InGaAs/GaAs quantum well-dot (QWD) nanostructures with the frontal-end and back-end input of radiation have been studied. A PD with 40 rows of QWDs exhibited a spectral responsivity of up to 0.4 A/W in the 950–1100 nm optical range at a –5-V bias voltage. The decay time constant of pulsed response for PDs with an input area of 1.4 × 10–4 cm2 was ~250 ps.