Purpose: This article aims to analyze and summarize the practical experience of deploying and integrating platforms for open journals, conferences, and repositories with support for the Open Archives Initiative Protocol for Metadata Harvesting (OAI-PMH). It highlights the errors and challenges that journal and repository managers and administrators, as well as conference organizers, may encounter and offers recommendations to prevent and avoid these issues. Design / Method / Approach: The research is based on the analysis of real cases of deploying platforms (...) for open science, including the analysis of errors and difficulties encountered during this process. The methodology includes the analysis of real-world cases, applying methods such as testing, validating the OAI-PMH protocol, observation, and studying regulatory and technical documents. Findings: Key errors and difficulties that organizers may face when creating open journals, conferences, and repositories with OAI-PMH support have been identified. Specific solutions are proposed to ensure the reliable operation of the metadata harvesting protocol (PMH), initial setup, and further integration of these platforms. Theoretical Implications: The study extends the understanding of the problems and challenges in the field of open science, particularly concerning the organizational and technical aspects of platforms with OAI-PMH support. Practical Implications: Practical recommendations are provided for administrators and managers of open journals, conferences, and repositories to avoid common mistakes and effectively use OAI-PMH to ensure data interoperability and accessibility. Originality / Value: The article presents an original analysis of real cases of implementing and integrating platforms with OAI-PMH support, making it a valuable resource for practitioners in the context of deploying platforms for open science. Research Limitations / Future Research: The study is limited to the analysis of specific cases and does not cover all possible aspects of deploying and integrating web applications with OAI-PMH support. Future research may focus on the quantitative analysis of the effectiveness of implementing these platforms and their long-term impact on open science. Paper Type: Case Study / Practitioner Paper. (shrink)

Today, the space industry is undergoing a period of significant technological advancement. Continuous progress in additive manufacturing technologies and the adoption of modern materials for 3D printing are driving this transformation. This trend has intensified competition among various space companies—both state-owned and private—each striving to introduce innovative and unique solutions. FlightControl Propulsion, a private space company in Ukraine, is one such example. This study focuses on the design of the power frame for a low-thrust liquid rocket engine. Power frames in (...) rocket engines must withstand significant mechanical loads. The application of topology optimization and high-strength steels enables the development of compact and efficient power frames that are substantially lighter than traditional designs. Additive manufacturing not only significantly reduces the production time of various parts and assemblies but also offers nearly unlimited possibilities for creating complex geometric shapes. What was previously challenging or even impossible to manufacture using conventional methods has now become feasible. This work examines a component fabricated using Selective Laser Melting (SLM) technology. A structured algorithm for topology optimization is described, along with the fundamental principle of the SIMP (Solid Isotropic Material with Penalization) topology optimization method. Numerical modeling of the stress-strain state for the initial design variant is performed using the finite element method (FEM) in a computer-aided engineering (CAE) environment. A computational finite element mesh is generated, and the safety margins of the design are evaluated. Following topology optimization, the final design variant is determined, and numerical modeling of the stress-strain state is repeated for the optimized design. The final design is then prepared for manufacturing and subsequent experimental testing. (shrink)

High-manganese steel is characterized by a stable austenitic structure over a wide temperature range and the ability to strengthen during mechanical deformation. However, factors such as unstable mechanical properties in the initial state, susceptibility to thermal embrittlement, and poor machinability hinder its widespread use. This study investigates the effect of temperature-time parameters on the structure and properties of 9Г28Ю9МВБ steel. It was found that during slow cooling from temperatures of hot deformation, a large number of coarse phase particles of gray-blue (...) color are precipitated in the steel, leading to a sharp decrease in impact toughness. It has been established that in the temperature range of 500-800 °C, the decomposition of the solid solution occurs with the precipitation of particles of the strengthening K-phase - (Fe,Mn)3AL,Cx. Simultaneous decrease in hardness and impact toughness in the temperature range of 750-950 °C contributes significantly to improved machinability. The lowest values of mechanical properties are achieved during aging at 700 °C, with the maximum improvement in machinability compared to other aging temperatures. For example, with an increase in the temperature of isothermal holding at 650 °C for 35 hours, the machinability improves by almost 1.7 times, and at the same duration at 700 °C - by 2.4 times. With an increase in the holding temperature to 950 °C for 35 hours, the machinability of the steel increases only by 1.6 times, which is due to less intensive decomposition of the supersaturated solid solution. Studies of the effect of annealing temperature on the uniformity of austenitic steel allowed to develop a heat treatment regimen for 9Г28Ю9МВБ austenitic steel, which includes heating to 1250°C, holding for 2 hours at this temperature, and subsequent cooling in water to fix a homogeneous supersaturated solid solution. After such heat treatment, the stripe-like microchemical inhomogeneity is significantly reduced, and the anisotropy coefficient does not exceed 1.1 units for all types of steel products. (shrink)

The “Challenges and Issues of Modern Science” collection comprises scientific research on relevant topics related to the latest advancements in various fields of science. Emphasis is placed on developing aerospace technology, thermodynamics and energy, mechanical engineering, materials science and technologies, automation, electronics and telecommunications, information technology, project management, ecology, and industrial and environmental safety. It can be helpful for professionals in the respective fields, scientists, educators, and students. The presented material will help readers expand their knowledge of diverse approaches to (...) solving current scientific and practical issues. The papers are published in the author's edition. До збірника «Виклики та проблеми сучасної науки» увійшли наукові праці з актуальних тем, що пов’язані з найновішими досягненнями в різних галузях науки. Акцентується увага на розвитку аерокосмічної техніки, термодинаміки та енергетики, машинобудування, матеріалознавства та технологій, автоматизації, електроніки та телекомунікацій, інформаційних технологій, управління проектами, екології, промислової та екологічної безпеки. Може бути корисним для фахівців у відповідних галузях, науковців, викладачів та студентів. Поданий матеріал допоможе читачам розширити знання про різноманітні підходи до розв’язання актуальних науково-практичних задач. Матеріали публікуються в авторській редакції. (shrink)

"Challenges and Issues of Modern Science" serve as an in-depth exploration of contemporary trends, sustainable development initiatives, and global concerns within the realm of scientific inquiry. The papers represent a collaborative effort by experts, researchers, and practitioners from various disciplines to address the multifaceted challenges facing modern science. Through in-depth analysis, empirical studies, and theoretical frameworks, the contributions in these proceedings aim to shed light on emerging trends, propose innovative solutions, and foster dialogue on critical issues shaping the future of (...) science and technology. By encapsulating the latest research findings and insights, the proceedings serve as a valuable resource for scholars, policymakers, and industry professionals, contributing to the advancement of knowledge and the sustainable development of our global community. Scope covers a wide range of topics and disciplines related to modern science. It includes but is not limited to Aerospace Vehicles, Engines, Energy, and Thermotechnics, Innovative Technologies in Mechanical Engineering, Structural and Functional Materials, Integrated Automation Technologies and Robotics, Control Systems, Telecommunications and Navigation, Information Technology and Cybersecurity, Project Management and Leadership, and Ecology, industrial, and environmental safety. The journal welcomes empirical studies, theoretical frameworks, and practical applications that contribute to the understanding and resolution of challenges in contemporary science. (shrink)