Odesa National Maritime University

This article addresses the critical challenge of optimizing ship machinery maintenance systems by integrating digital strategies. It examines adaptive maintenance approaches that consider real-time equipment condition, predictive analytics, and cost efficiency. A comparative analysis of existing methodologies is presented, highlighting their advantages and limitations. The study introduces an enhanced framework that incorporates machine learning models, sensor-based monitoring, and an improved decision-making process for maintenance scheduling. Experimental results demonstrate the effectiveness of adaptive strategies in minimizing downtime, reducing operational costs, and extending the lifespan of ship machinery. Practical applications and long-term implications for maritime industry stakeholders are also discussed. Additionally, the article explores the economic and operational impacts of changes in technical conditions, emphasizing cost-effectiveness and time optimization in servicing practices. The findings advocate for adaptive maintenance approaches that ensure efficient ship operation, reduce downtime, and enhance the overall productivity of maritime transport.

Shaft misalignment is considered as a defect which forms additional forces and reaction moments in the cage area creating a preload on the shaft and bearing and also changing the spectral structure of the vibration signal. These structural changes were analyzed, and typical diagnostic features for assessing the development of damage in the bearing by the methods of periodically non-stationary random processes were summarized. The results of processing and analysis of vibration acceleration signals obtained during laboratory tests on a vibrating stand of the BBC-R 6205 2RS/P6 bearings at different angular misalignment values were presented.

We continued our analysis of the O-C diagram of the EW-type eclipsing binary V405 Dra using recently available data. We refined the orbital parameters of the third body responsible for the short-period oscillations in the O-C curve, obtaining P_3=513.12(20) d, a_12sin i_3=0.3862(15) AU, and e_3=0.1690(48). Assuming a total mass of 1.56 M_⊙ for the eclipsing binary, the minimum mass of the third body is estimated to be about 0.5 M_⊙. We also investigated the complex long-term O-C trend and found that it may be partially explained by the light-time effect caused by a possible fourth body, with a characteristic period of about 23.5 yr and a minimum mass of about 0.9 M_⊙. However, the fourth-body model cannot fully reproduce the observed long-term variation, particularly the earliest data, and the nature of part of the long-term trend remains unexplained.

In the current conditions of economic integration and development of transport corridors, systematic optimization of the business activities of resource suppliers, product manufacturers, and resource and product transporters within a single production and transport holding company that supplies consumer markets with products is becoming highly relevant.A large number of recent publications, mainly descriptive in nature, are devoted to these logistical issues. Publications using economic and mathematical tools examine production and transport systems that include only manufacturers, transporters, and consumers of products; the supply of resources used to manufacture the final product is ignored. Therefore, the purpose of this article is to construct and analyze economic and mathematical models of a generalized system of entrepreneurial activity of a production and transport holding, taking into account not only products but also resources.Due to the existence of goods that replace or complement each other, the price of each type of product depends not only on the volume of that product, but on the volume of all types of products on the market. The types of dependencies between the costs of resource extraction, product manufacturing, and transportation are determined.An economic-mathematical model of the task of maximizing the holding's profit as the difference between revenues in all markets and total costs of production and transportation of resources and products has been constructed. The conditions for theoptimality of the plan have been found and interpreted.A change in any of the system's characteristics causes a change in the optimal plan not only for the corresponding component, but also affects the entire optimal plan. Market demand parameters for products affect optimal production volumes and resource transportation, etc.We note the possibility of market decentralization of the studied production and transportation system, when it is no longer a single optimization problem for the entire system that is being solved, but each of the system participants (suppliers and transporters of resources and products) maximizes only their own profit, using as their control parameter the vector volume of their own production or transportation – at certain prices for resources and products and transportation tariffs.

Automatic Identification System Aids to Navigation (AIS AtoNs) represent a transformative technology for inland water transport, increasing navigation safety and operational efficiency. This paper focuses on the deployment and performance of AIS AtoNs on a selected section of the Danube River. The paper evaluates the benefits, challenges, and results of a pilot testing and offers insights into the practical application of AIS AtoNs in real-world conditions. The results show improvements in navigation safety, operational efficiency, and environmental sustainability, while addressing issues such as energy consumption and reliability during adverse conditions. Additionally, the study identifies the need for standardized anchoring systems and advanced energy management solutions to enhance buoy stability and operational continuity. These findings provide a foundation for future advancements in AIS AtoNs integration, emphasizing their potential for global adoption in inland navigation systems.