Technical Solutions Research Articles

The results of research on technological indicators in the experimental module for growing broiler chickens

Russia ranks fifth in the world in poultry meat production. In the period from 2010 to 2021, the volume of production of this type of product increased by 1.77 times, which in physical terms is 2,190 thousand tons. The largest volume of poultry meat production, 89.7%, falls on the meat of broiler chickens. This indicator is justified by consumer preferences of the retail market, a low feed conversion rate, a high level of automation of production processes, as well as the possibility of up to 8 production cycles per year. The main share, amounting to 93%, of broiler chicken meat production is accounted for by large agricultural enterprises. Households of the population and peasant farms account for 7% of production. This result is observed due to the lack of technical and technological solutions for small-scale production, providing for the use of automation of production processes, which leads to a decrease in productivity and an increase in poultry mortality. The combination of these factors increases the cost of finished products, making small-scale production uncompetitive. To solve this problem, a project has been developed and a prototype of a technological module for fattening broiler chickens has been manufactured. The production capacity of the module is 2,800 broiler chickens per year. The module uses a cellular method of keeping poultry on a mesh flooring. As a result of the conducted studies, the feed conversion rate was 1.66, the cost of water was 3.4 liters, electricity was 3.22 kWh and labor was 0.051 people per kilogram of live weight. The obtained indicators are comparable with those of large poultry farms, which allows us to conclude that it is advisable to use technological modules at small poultry enterprises.

Combined Wind Turbine Protection System

The increasing deployment of wind turbines in technologically advanced nations underscores the need to enhance their reliability, extend their operational lifespan, and minimize failures. The current protection devices for wind turbine components do not sufficiently shield them from various external factors that degrade performance. This study addresses the environmental and technical challenges that disrupt wind turbine operations and reviews existing research and technical solutions for protecting individual components, supported by experimental findings. Using a decomposition method followed by the integration of protection components, we propose a combined protection system designed to improve the overall resilience of wind turbines. The proposed system aims to reduce incidents, extend service life, and increase reliability, addressing a critical gap in wind energy technology and contributing to its continued development and efficiency.

Issues of personal data protection when using cloud technologies

It is indicated that in today’s digital world, where the amount of stored and processed data is growing at a frantic pace, issues of personal data protection are becoming increasingly important. With the proliferation of cloud technologies that allow companies and individuals to store and process information on remote servers, a new spectrum of threats to data privacy and security is emerging. The article examines the issue of personal data protection when using cloud technologies, in particular, the need to integrate legal and technological aspects to ensure comprehensive protection. The impact of international regulatory acts, such as GDPR (General Data Protection Regulation) and CCPA (California Consumer Privacy Protection Act), on cloud data protection processes is analyzed. Particular attention is paid to problems arising from differences in the legal regimes of different countries, which complicate data management at the international level. The article examines in detail modern technical solutions, such as data encryption and multi­factor authentication, which are key elements in protecting confidential information. These technologies have been found to provide a high level of protection, but also have their vulnerabilities. Based on this, it is proposed to invest in the latest technologies, in particular quantum encryption and artificial intelligence, to improve the effectiveness of data protection. Practical cases of data leaks are separately considered, which emphasize the importance of proper configuration of security systems and regular monitoring. Analysis of the results of empirical research shows the need to adapt business processes to changes in the regulatory environment and introduce new technologies to reduce risks. Based on the received data, recommendations for organizations are formulated, which include reviewing data protection policies, investing in modern technologies and training employees. The conclusions of the article emphasize the need for a comprehensive approach to ensuring the protection of personal data in cloud environments. This involves taking into account both modern technologies and current legal requirements to ensure adequate data protection and minimize possible risks.

Emergency Detection in Smart Homes Using Inactivity Score for Handling Uncertain Sensor Data

In an aging society, the need for efficient emergency detection systems in smart homes is becoming increasingly important. For elderly people living alone, technical solutions for detecting emergencies are essential to receiving help quickly when needed. Numerous solutions already exist based on wearable or ambient sensors. However, existing methods for emergency detection typically assume that sensor data are error-free and contain no false positives, which cannot always be guaranteed in practice. Therefore, we present a novel method for detecting emergencies in private households that detects unusually long inactivity periods and can process erroneous or uncertain activity information. We introduce the Inactivity Score, which provides a probabilistic weighting of inactivity periods based on the reliability of sensor measurements. By analyzing historical Inactivity Scores, anomalies that potentially represent an emergency can be identified. The proposed method is compared with four related approaches on seven different datasets. Our method surpasses existing approaches when considering the number of false positives and the mean time to detect emergencies. It achieves an average detection time of approximately 05:23:28 h with only 0.09 false alarms per day under noise-free conditions. Moreover, unlike related approaches, the proposed method remains effective with noisy data.

Optimising Portugal’s 2050 energy system: Electric vehicles and hydrogen integration using Grey Wolf Optimiser and EnergyPLAN

The global shift to sustainable energy, driven by climate concerns and energy security, is backed by worldwide governmental commitments to reduce greenhouse gas emissions and enhance renewable energy sources in the energy systems. In 2016, the Portuguese Government pledged to carbon neutrality by 2050 as part of this global effort. This article proposes technical solutions for reducing carbon dioxide emissions and increasing renewable energy in the Portuguese mainland energy system by 2050, considering the targets set by the government. An energy system modelling approach based on the Grey Wolf Optimiser and the EnergyPLAN software was introduced. Seven scenarios for 2050 assess the impacts of transport electrification and hydrogen grid integration while minimising costs and/or carbon dioxide emissions. The results show that achieving a nearly 100% renewable electricity system and carbon neutrality is possible, considering a carbon capture ranging from 2.65Mt to 5.87Mt. The 2050 energy system requires a minimum battery storage of 5.1GWh and a minimum natural gas storage of 2,063GWh. Transport electrification requires an increase in the total installed capacity by at least 1.83GW, while hydrogen integration increases it by a minimum of 8.25GW. Developing interconnection capacity beyond 15% of the total installed capacity is crucial for grid stability and reducing fossil fuel dependence.

Monitored and Cared for at Home? Privacy Concerns When Using Smart Home Health Technologies to Care for Older Persons

Background States and families are facing growing challenges provide adequate care for older persons. Smart home health technologies (SHHTs) in the forms of sensor or robotic devices have been discussed as technical solutions for caregiving. Ethical and social concerns are raised with the use of such technologies for caregiving purposes, a particularly prominent one being privacy. This paper contributes to the literature by distinguishing privacy concerns into both the type of technologies and conceptual dimensions. Methods Data for this paper stem from sixty semi-structured interviews with older persons, informal, and formal caregivers living in the German-speaking regions of Switzerland. All information related to privacy, that were initially inductively coded, were thematically sorted into four dimensions of privacy (physical, psychological, social, and informational) and by the type of technologies studied. Results Participants were especially concerned about privacy intrusions from smart wearables and ambient sensors than robotic technologies, which may be due to the relative lack of familiarity with the latter. Informational privacy was evident in the context of data collection capacities and potential for misuses of data. The installation and implementation of both visual and ambient sensors induced discomfort to their senses of physical space. Alerts of smart wearables and obtrusive sightings of SHHTs garnered worries related to stigmatization and manipulation, indicating intrusions into end-users’ psychological privacy. Little discussions of social dimensions of privacy were evident in the data, even toward robotic technologies for their functions to promote social interactions for older persons. Conclusions This paper is one of the first that use the stratification approach on empirical data to highlight the multi-faceted privacy concerns when technologies may be implemented in elder care. Our paper could thus supports potential end-users in deciding which technologies to use and how to balance different privacy concerns against other values that they may hold important.

Insurance secrecy

This article discusses the issues related to insurance secrecy, which is an important matter from the perspective of insurance practice. The insurance is based on clients’ confidence in the payment of benefits if an event covered by the insurance has occurred as well as on the assumption that crucial data concerning major facts of the client’s life provided in the course of concluding the insurance contract (specifically in the medical survey concerning the insured’s health condition) and while the insurance relationship persists will be disclosed to nobody in an unauthorised manner. Insurance secrecy is a professional secrecy regulated by the Act of 11 September 2015 on Insurance and Reinsurance Activity in order to ensure the confidentiality of data transmitted and to maintain clients’ confidence in insurance companies. Insurance secrecy is related to the protection standard of the right to privacy, with this right constituting one of the major values.This article deals with the temporal, territorial, material and subjective scope of applying the insurance secrecy, principles of liability for the breach thereof, as well as the admissibility of consent to release the information covered by the secrecy, by citing different voices concerning those issues. In addition, the author presents judgments relating to a number of aspects concerning the practical application of provisions concerning the insurance secrecy and highlighting the basic characteristic of the institution in question. Some practical aspects related to the application of the insurance secrecy are also addressed, taking into account the current realities of the insurance market, including technical solutions (e.g. social media), by means of which beneficiaries of insurance contracts or the insured themselves inform the public about the liquidation procedure, which puts the insurance companies, or more broadly the insurance distributors, in a more difficult position in terms of their image. Finally, some de lege ferenda proposals are put forward in respect of those aspects of insurance secrecy, which, in the authors’ opinion, need to be dealt with by the legislator.

The potential of federated learning for self-configuring medical object detection in heterogeneous data distributions

Medical Object Detection (MOD) is a clinically relevant image processing method that locates structures of interest in radiological image data at object-level using bounding boxes. High-performing MOD models necessitate large datasets accurately reflecting the feature distribution of the corresponding problem domain. However, strict privacy regulations protecting patient data often hinder data consolidation, negatively affecting the performance and generalization of MOD models. Federated Learning (FL) offers a solution by enabling model training while the data remain at its original source institution. While existing FL solutions for medical image classification and segmentation demonstrate promising performance, FL for MOD remains largely unexplored. Motivated by this lack of technical solutions, we present an open-source, self-configuring and task-agnostic federated MOD framework. It integrates the FL framework Flower with nnDetection, a state-of-the-art MOD framework and provides several FL aggregation strategies. Furthermore, we evaluate model performance by creating simulated Independent Identically Distributed (IID) and non-IID scenarios, utilizing the publicly available datasets. Additionally, a detailed analysis of the distributions and characteristics of these datasets offers insights into how they can impact performance. Our framework’s implementation demonstrates the feasibility of federated self-configuring MOD in non-IID scenarios and facilitates the development of MOD models trained on large distributed databases.

Management of radio-frequency interferences for space traffic management: Current regulations, operations practice, technology mitigation solutions and future trends

Radio-Frequency Interference (RFI) has a large impact on the business of commercial satellites communications and will have an increasingly important role in the next years and decades due to the spread of the launched spacecraft population.This paper presents the current state-of-the-art for Space Traffic Management -related RFI from a regulatory point of view, with regards to preventing and correcting harmful interference, linked to the International Telecommunication Union, and from a technical point of view, with technical procedures, workflows and innovative technology solutions for preventing and mitigating RFI. Finally, emerging technology trends and future directions are presented.

Optimization of Proportions of Alkali-Activated Slag-Fly Ash-Based Cemented Tailings Backfill and Its Strength Characteristics and Microstructure under Combined Action of Dry-Wet and Freeze-Thaw Cycles.

To enhance the application of alkali-activated materials in mine filling, cemented tailings backfill was prepared using slag, fly ash, sodium silicate, and NaOH as primary constituents. The effects of the raw material type and dosage on the backfill were examined through a single-factor experiment. Additionally, response surface methodology (RSM) was utilized to optimize the mixing ratios of the backfill, with a focus on fluidity and compressive strength as key objectives. The evolution of backfill quality and compressive strength under the combined effects of dry-wet and freeze-thaw (DW-FT) cycles was analyzed. The hydration products, microstructure, and pore characteristics of the specimens were analyzed using X-ray diffraction (XRD), scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS), and nitrogen adsorption tests (NATs) across varying cycles. The results demonstrate that the optimal backfill composition includes 47.8% fly ash, 6.10% alkali equivalent, and a 1.44 sodium silicate modulus. The macroscopic behavior of the backfill under DW-FT coupling followed this progression: pore initiation → pore expansion → crack formation → crack propagation → structural damage. After a minor initial increase, the backfill strength steadily decreased. Microscopic analysis revealed that the decline in internal cementation products and the deterioration of pore structure were the primary causes of this strength reduction. Thus, the DW-FT coupling can cause significant erosion of the backfill. The technical solutions presented in this paper offer a reference for solid waste utilization and provide valuable insights into the durability of backfill under DW-FT coupling.

Enhanced Self-Checkout System for Retail Based on Improved YOLOv10.

With the rapid advancement of deep learning technologies, computer vision has shown immense potential in retail automation. This paper presents a novel self-checkout system for retail based on an improved YOLOv10 network, aimed at enhancing checkout efficiency and reducing labor costs. We propose targeted optimizations for the YOLOv10 model, incorporating the detection head structure from YOLOv8, which significantly improves product recognition accuracy. Additionally, we develop a post-processing algorithm tailored for self-checkout scenarios, to further enhance the application of the system. Experimental results demonstrate that our system outperforms existing methods in both product recognition accuracy and checkout speed. This research not only provides a new technical solution for retail automation but offers valuable insights into optimizing deep learning models for real-world applications.

Continuous recovery of tellurium and cadmium from simulated CdTe leachates using a fixed-bed-column adsorption system

Rare element resource (Te) loss and heavy metal (Cd) pollution, derived from waste photovoltaic CdTe cells, have attracted considerable attention in the cleaner production and environmental protection field. However, there are several technical barriers in conventional adsorption strategies for the continuous recovery Te(Ⅳ) and Cd(Ⅱ) due to single-component recovery, inefficient adsorbent utilization and less automation. Herein, this work presented a fixed-bed-column adsorption system for the continuous adsorption recovery of tellurium and cadmium from a simulated CdTe leachate using functional sludge-based adsorption fillers (LDO/SF and EDTA@LDH/SF) that prepared from water-processing sludge via hydrothermal synthesis, thermal activation and surface modification technologies. Breakthrough curves were analyzed for adsorption columns, considering initial concentration, flow rate, and filler height, with parameters evaluated using the Thomas and BDST models to determine the optimal separation parameters. During the continuous adsorption process, the column adsorption system with the filler layer height of 4 cm and liquid delivery rate of 1 mL/min can be used for continuous separation of more than 1000 mL of a simulated CdTe leachate and exhibits adsorption efficiencies of more than 96% and 82% for Te(Ⅳ) and Cd(Ⅱ), respectively. More importantly, the elution procedure was used to treat the column adsorption system with ion adsorption acceptances of 83% and 90% for Te(Ⅳ) and Cd(Ⅱ), respectively. Meanwhile, the functional sludge-based fillers demonstrated great regeneration and recycling capabilities, thus maximizing the utilization of adsorbents and saving treatment costs. This study has established a robust technical solution for the continuous recovery of tellurium and cadmium from simulated leachates, providing a practical framework for evaluating the efficiency of adsorption filler columns in actual applications.

A biomimetic fruit fly robot for studying the neuromechanics of legged locomotion

For decades, the field of biologically inspired robotics has leveraged insights from animal locomotion to improve the walking ability of legged robots. Recently, 'biomimetic' robots have been developed to model how specific animals walk. By prioritizing biological accuracy to the target organism rather than the application of general principles from biology, these robots can be used to develop detailed biological hypotheses for animal experiments, ultimately improving our understanding of the biological control of legs while improving technical solutions. In this work, we report the development and validation of the robot Drosophibot II, a meso-scale robotic model of an adult fruit fly,Drosophila melanogaster. This robot is novel for its close attention to the kinematics and dynamics ofDrosophila, an increasingly important model of legged locomotion. Each leg's proportions and degrees of freedom have been modeled afterDrosophila3D pose estimation data. We developed a program to automatically solve the inverse kinematics necessary for walking and solve the inverse dynamics necessary for mechatronic design. By applying this solver to a fly-scale body structure, we demonstrate that the robot's dynamics fit those modeled for the fly. We validate the robot's ability to walk forward and backward via open-loop straight line walking with biologically inspired foot trajectories. This robot will be used to test biologically inspired walking controllers informed by the morphology and dynamics of the insect nervous system, which will increase our understanding of how the nervous system controls legged locomotion.

CYBERSECURITY PRACTICES AND FRAUD PREVENTION AMONG GHANAIAN TELECOMMUNICATION FIRMS, A MIXED METHOD ANALYSIS

This study explores the effectiveness of cybersecurity practices in preventing fraud within Ghanaian telecommunication firms, adopting a qualitative research approach to gain in-depth insights into the challenges and strategies involved. By focusing on the perspectives of key personnel directly involved in cybersecurity and fraud prevention, the study aims to uncover critical factors influencing the success of these practices. A case study design is employed, examining cybersecurity implementation across five major telecommunication firms in Ghana. The sample consists of 15 participants, including IT managers, cybersecurity officers, and fraud prevention specialists, selected through purposive sampling to ensure relevant and insightful data collection. Semi-structured interviews are used as the primary data collection method, allowing participants to provide detailed and nuanced information on their experiences with cybersecurity measures. Thematic analysis is employed to identify key patterns and themes within the data, highlighting the role of insider threats, regulatory frameworks, and employee behavior in contributing to fraud. The findings indicate that while robust technical measures such as encryption, multi-factor authentication, and intrusion detection systems play a significant role in reducing fraud, challenges in enforcement, compliance, and employee behavior remain critical barriers. The study concludes that a holistic approach, combining technical solutions with organizational culture improvements and stronger regulatory enforcement, is essential for enhancing cybersecurity effectiveness in Ghana’s telecommunication sector. Recommendations are made for improving incident response times, regulatory support, and employee training programs, as well as fostering greater collaboration between firms and regulatory bodies to strengthen fraud prevention efforts.<p> </p><p><strong> Article visualizations:</strong></p><p><img src="/-counters-/soc/0709/a.php" alt="Hit counter" /></p>

Methods of Utilization of Lithium-ion Вatteries. Part 1. Basic Approaches to Recycling

Approaches to the utilization of lithium-ion batteries using hydrometallurgical and pyrometallurgical recycling methods are described, their advantages and disadvantages are considered. The global nature of the problem associated with high growth rates of lithium-ion batteries market and underdeveloped infrastructure for their utilization, which leads to environmental pollution by toxic components of batteries, is outlined. It is concluded that the development of new technical solutions in this area should be carried out with a balance between economic efficiency and compliance with environmental standards.

Software System SPDIAL

Spiroid gears are direct competitors to traditional technical solutions - worm and hypoid gears; and they have proven themselves in a large number of specific technical applications, providing greater strength, smaller size, and easier production. However, their design process is much less subject to being typical and standard and to resulting in simple engineering techniques. In fact, effective solutions can be obtained only by actually researching the space of parameters. An indispensable tool for this is a computer-aided design and research system. The paper presents the summary of such a system SPDIAL+ for worm-type gears (worm, QN-gears, spiroid) developed at Izhevsk scientific school in the field of gears and gearboxes. In particular, the possibilities of designing a conjugated gear, choice of gearwheel cutting parameters, analysis of gears under the action of errors and loads are considered. The role and results of applying the program as the main tool for research, design and innovations like new varieties of gears, their new properties in specific applications, new methods and techniques of tooth machining are shown.

Adaptive Matching of Discrete Antenna Tuning Units of High Frequency Band to Varying Load Impedance

The issue of matching the antenna with thetransmitter-receiverplays a primary role in radio communications. The matching problem is relevant for different ranges and is solved in many ways. In the high frequency wave range, matching has a number of features when using an antenna coupler based on discrete elements consisting of capacitance and inductance boxes. The article discusses the concept of fast matching of high-frequency amplifying paths ofdecametric wavestransceivers with non-stationary loads using discrete antenna couplers. An innovative approach has been developed to the tuning process when changing the operating frequency and ensuring self-adaptation of the antenna coupler when changing the impedance, based on methods for quickly searching for the geometric proximity of points. A quick method for configuring the antenna coupler is proposed, eliminating the procedure for recalculating the input impedance based on the results of measuring the input impedance of the antenna coupler. When using it, the speed of setting the antenna coupler at the current operating frequency is limited only by the time of a single state change of the discrete power circuit, which in the case of electromagnetic relays is numerically equal to their switching time. The configuration of the antenna coupler using the method of fast search for the geometric proximity of points is based on a set of frequency cards with settings options. Such cards can be recalculated for the reference plane between the generator and the antenna coupler input for all combinations of discrete elements in accordance with the known matrix model of a discrete power circuit. This eliminates the complicated procedure of recalculating the input impedance of the antenna using complex numbers. The technical result of the proposed innovative method of antenna coupler configuringis simplification, tracking of systematic errors of the impedance meter, elimination of time-consuming calculations with complex numbers, expansion of the method functionality, reduction of the tuning duration and improvement its quality. The practical significance lies in the fact that the implementation of the proposed technical solutions in the high frequency range communications means can significantly (about 100 times) limit the duration of preparation for a radio communication session, eliminate the procedure for recalculating the antenna input impedance and reduce the resource requirements of switching elements.

Cyber Security Controls and Countermeasures

Today's digital economy encompasses a conglomeration of devices, data, applications, and complex networks that can be hosted on-premises, in data centers or in cloud environments to support business functions. As a cybersecurity professional, you will be tasked to manage risks like cyber threats and data breaches in the workplace. The risks may emanate from the data that resides in the systems, like servers, computers or external drives and the physical assets themselves, like routers and switches. The onus is on preventing security events and limiting the damage or consequences of any event that might happen. Managing these risks in an organization can be achieved by implementing cyber security controls and countermeasures. Cyber security controls can be categorized into three distinct major groups: administrative control, physical control, and technological control. The administrative controls focus on security policies, guidelines, rules, procedures and standards designed by management to control access and utilization of confidential information. Physical control refers to a set of IT security controls deployed at the physical premise to prevent unauthorized physical access to data centres. Technical controls involve the use of systems and technical solutions to prevent security events in networks and cloud platforms. Additionally, when implementing security controls, the function of cyber security controls can be broadly divided into seven groups: directive, deterrent, preventive, compensating, corrective, detective, and recovery controls. Furthermore, security frameworks such as NIST, CIS controls COBIT, and ISO/IEC series form the cornerstone of cyber security controls and countermeasures. The aforementioned aspects will be discussed further in the later sections. For now, it is to provide a general picture of the cyber security controls and countermeasures. Keywords – Security Controls, Countermeasures, Frameworks, Information Systems, Risk

FEATURES AND EXPERIENCE OF CONVERTING GAS-OIL BOILERS OF INDUSTRIAL CHP PLANTS TO BURNING BIOMASS AND SUB-BITUMINOUS COAL

The paper examines the features of biomass as a fuel and substantiates that for agrobiomass waste with a high content of alkali metal oxides and slag properties of ash, it is more appropriate to burn it in a dense bed in the form of pellets, which ensures a temperature at the exit from the furnace of no more than 900 °C, a low part of fly ash and low content of unburned carbon in it, and so eliminates the risk of smoldering deposits with their melting and slagging. Technical solutions are given and the experience is presented of gas and oil boilers of CHP plants of sugar factories reconstruction with their transfer to the burning of biomass and/or coal in a dense bed on a direct-flow grate with the replacement of the air heater with air-water heater, with the addition of stages of the boiling economizer to compensate for the decrease in the heat perception of the furnace screens, maintaining the overall height of the boiler and the plane of the boiler cell. The reconstruction of boilers according to the developed technical solutions is possible to perform in the interval between production seasons, its implementation on boilers BKZ-75 GMA of Radekhiv and Chortkiv sugar factories allowed to achieve acceptable technical, economic and environmental indicators and ensured payback due to the difference in commercial prices of gas and of agrobiomass pellets. It is proposed to replicate the positive experience in the creation of decentralized regulating thermal generation capacities of the country. Bibl. 30, Fig. 3, Tab. 4.

ANALYSIS OF THE ENERGY EFFICIENCY OF TECHNICAL SOLUTIONS OF THE HEAT-DRIVEN SHIP EJECTOR REFRIGERATION MACHINE FOR OBTAINING SUB-ZERO TEMPERATURES

Marine refrigeration machines are responsible for large amounts of electricity consumption, as well as direct emissions of high global warming potential (GWP) refrigerants, so they need to be gradually upgraded. The possibility of using a ship ejector refrigeration machine with two-stage compression, consuming waste heat, as well as a cascade compression-ejector refrigeration machine to obtain the temperatures of minus 28–27 °C was analyzed. It was shown that the traditional indicator of the efficiency of heat-driven refrigeration machines COPtherm ot be recommended for the selection of energy-efficient modes of operation of ejector refrigeration machines that consume waste heat. As a criterion for the energy efficiency of ejector refrigeration machines that consume waste heat, it is proposed to analyze COPmechTot, which takes into account the electric power of pumps, fans, as well as units that provide “feeding” the refrigeration machine with waste heat. A two-stage ejector refrigeration machine that consumes waste heat with a temperature of 95–45 °C and is intended for the operation of a ship ice generator (boiling temperature — 28 °C) loses to a traditional vapor compression refrigeration machine in terms of energy consumption: COPmechTot = 1.266 vs. COPmechTot = 1.52. A cascade vapor compression ejector refrigeration machine that consumes waste heat with a temperature of 85–95 °C and is designed to provide refrigeration (boiling temperature — 27 °C) of ship provision chambers is more attractive than a traditional vapor compression one: COPmechTot = 2.37 vs. COPmechTot = 1.82. An alternative technical solution for the production of sub-zero temperatures on ships, which the authors plan to consider in further research, is a refrigeration machine with two-stage compression. It uses a compressor in the first stage and an ejector in the second stage. Bibl. 26, Fig. 7, Tab. 1.