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This issue of the RECENT journal was edited with the support of: ContentsSpur Gears with Curved Directrix: Diversity and Methods of Generation. A Patent Study
RECENT J. (2025), 75:005-017 https://doi.org/10.31926/RECENT.2025.75.005 Abstract Gear wheels and mechanisms deploying spur gears have been known since antiquity. Leonardo da Vinci's studies on gears are also exciting. Although there is no explicit information about how gears were cut in the ancient and medieval world, it is unanimously accepted that tooth profiles were not generated kinematically. The modern period is characterized by machines and movement, and gears are practically ubiquitous. Among the cylindrical gears, the most frequently used ones are those with straight directrix and those with helical cylindrical gears (cylindrical gears with inclined teeth), both types being rectifiable. Monographs or specialized treatises are rare that even mention that cylindrical gears can also have curved teeth, i.e. curved directrix to the associated reference rack. In the last five decades, and only sporadically before, explicit interests in and achievements emerged related to cylindrical gears with curved directrices, relevant in this sense being patents and doctoral theses. Most of the works mainly concern cylindrical teeth with involute and circular directrix, as well as methods and machines for their machining. At the limit, cambered teeth can also be considered cylindrical teeth with curved directrix. Cylindrical gears with poly-hypocycloid directrix and corresponding machining methods are a subject initiated by Professor Emil Botez and addressed exclusively by researchers from the Politehnica University of Bucharest. Romanian researchers are actively contributing to furthering knowledge about various cylindrical gear with curved directrices and their manufacturing methods. Keywords spur gear, curved directrix, methods of generation, specialized machine tools, patent A Research for the Textile and Composite Material Sectors. Part 1: Current Situation
RECENT J. (2025), 75:018-028 https://doi.org/10.31926/RECENT.2025.75.018 Abstract This journal paper provided an in-depth examination of Bursa's textile sector, focusing on technical textiles and composite materials. The study was conducted using a questionnaire survey to gather detailed responses from a wide range of textile companies in the region. The survey sought to collect comprehensive information about industry practices, technical advancements, and operational issues within the fields of composites and technical textiles. Key findings showed that 38% of surveyed enterprises primarily exported their products directly. Furthermore, 34% of enterprises used both direct and intermediary export routes, while only 4.3% relied solely on intermediaries. This distribution demonstrated a strong preference for direct export methods within the sector. Overall, the study provided a detailed view of past business practices and export initiatives, along with an assessment of the institutional support offered to the industry. The findings offered valuable insights into the evolving landscape of the textile industry, highlighting trends in material utilization, export techniques, and the effects of technological advancements on competitiveness and sustainability. Keywords technical textiles, composite materials, questionnaire survey, Bursa Laser Cladding of Ni-Based Powders on S355MC High-Strength Steel Substrate
RECENT J. (2025), 75:029-036 https://doi.org/10.31926/RECENT.2025.75.029 Abstract Laser cladding is a technology in the field of surface engineering. Its characteristics, like versatility, high density of the energy, the various possibilities in selection of the laser beam led to metallic coatings with high quality. This quality however is dependent on the laser cladding equipment, materials and process parameters. The research work aims to investigate the geometrical characteristics of the laser cladding coatings and the behavior regarding bonding with the substrate of four different Ni-based powders on the same base material, S355MC. The S355MC is chosen because of its versatility and high usage in industrial fields. The four Ni-based powders are Metco 12C, Metco 14E, Metco 16CNS and Metcoclad 718. The experimental set-up was formed from a Trumpf TruPulse 556 milliseconds pulsed laser and Precitec WC50 as cladding module. Keywords laser cladding, Ni-based powder, S355MC, pulsed laser Kinematic Requirements for Machining Cylindrical Surfaces Characterized by Straight Directrix and Circle Generatrix
RECENT J. (2025), 75:037-046 https://doi.org/10.31926/RECENT.2025.75.037 Abstract A workpiece is defined by one or more unit surfaces that are continuous with each other, each unit surface being characterized by a directrix curve and a generatrix curve. Each of these curves can be generated in six ways. Consequently, a unit surface can be obtained in 6x6 = 36 distinct ways using various processing methods (such as cutting, plastic deformation, or unconventional methods). Some of these methods are found in industrial practice, while others are possible but economically inefficient. Depending on the nature of the directrix and generatrix curves, certain theoretical methods for obtaining a unit surface are not yet known and require inventive effort to be revealed. This paper focuses on the methods for obtaining unit cylindrical surfaces where the directrix curve is a straight line described cinematically as the trajectory of a point and the generatrix curve is a circle. Keywords surface, directrix curve, generatrix curve, processing scheme, kinematic chain A Research for the Textile and Composite Material Sectors: Part 2: The Impact of Joint R&D and Prototyping Center on the Sectors
RECENT J. (2025), 75:047-056 https://doi.org/10.31926/RECENT.2025.75.047 Abstract This article provides a thorough examination of the textile industry in Bursa, with a focus on technological textiles and composite materials. Using a rigorous questionnaire survey, the study collected responses from a varied variety of textile enterprises in the region to investigate industry practices, technological breakthroughs, and operational problems connected to composites and advanced textiles. The study looked closely at the function of the Bursa Technology Coordination and R&D Centre (BUTEKOM), a crucial institutional participant in the sector's research, development, and innovation. The data show that 52.90% of enterprises rated the impact of the BUTEKOM initiative on their competitiveness as moderate, 29.40% as strong, and 11.80% as extremely low, demonstrating varying levels of gain from such institutional support. This study highlights the importance of BUTEKOM's initiatives in fostering innovation and competitiveness within Bursa's textile industry. Keywords technical textiles, composite materials, questionnaire survey, BUTEKOM, Bursa Integrating Sustainability in Business Administration - Benefits, Challenges, Future Perspectives
RECENT J. (2025), 75:057-064 https://doi.org/10.31926/RECENT.2025.75.057 Abstract The integration of sustainability into business administration entails the adoption of practices that prioritize economic profitability while also considering environmental and social responsibility. This concept is gaining prominence as businesses acknowledge their role in addressing global challenges, including climate change, resource depletion, and inequality. The aim of the paper is to emphasize the importance of sustainability practices for the development of the business administration sector focusing on benefits, challenges and future perspectives on the topic. The findings suggest that the adoption of sustainable practices by companies may result in certain benefits, including the enhancement of company image, the reduction of operational costs, and the attraction of new customers. However, it should be noted that this transition may present certain challenges, such as the need to balance immediate costs with long-term benefits. The study represents a reliable source of information for governments, scholars, and researchers. Keywords administration, business, challenges, future perspectives Green Transformation in Industry, Green Collar Professions and Adaptation Possibilities of Syrian Immigrants to This Process: A Case Study
RECENT J. (2025), 75:065-075 https://doi.org/10.31926/RECENT.2025.75.065 Abstract This study focuses on various aspects of the Green Transformation Process, including green transformation practices, industrial green transformation, the Green Deal, global developments, new jobs related to green transformation (green jobs), the Green Deal Action Plan, and evaluations of Bursa and Türkiye from a global perspective. It investigates and compiles information on the lives and employment processes of Syrian migrants under temporary protection in Bursa. Additionally, an action plan has been developed for the adaptation of individuals under temporary protection to the new jobs emerging from the green transformation process. For this purpose, the study first examines green transformation and green professions, followed by an analysis of the employment needs of Syrian migrants who have come to Türkiye. Research has been conducted on both the migration phenomenon and the processes of green transformation and green jobs. Keywords green transformation, green jobs, Syrian immigrants, need analysis
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