bluuebunny/crossref_metadata_2025 huggingface dataset:
A Study on Changes in Maritime Traffic Due to the Pandemic using AIS Big Data and Density Analysis
Authors: Kim Chae-Eun , Chi Junhwa , Kim Tae-Hoon , Lee Jeong-Seok
Published: December 2024

Maritime transportation is one of the most economically efficient methods of transporting large volumes of cargo and serves as a crucial vehicle for global trade, accounting for about 80% of worldwide commerce. In particular, since Korea is surrounded by sea on three sides, more than 90% of its import and export cargo heavily relies on maritime transportation. However, the COVID-19 pandemic that began in late 2019 has brought about changes in maritime traffic patterns due to global border controls and changes in economic activity. In particular, for Korea, which is highly dependent on maritime logistics, it is important to understand how the pandemic has affected maritime traffic density and the changes by vessel type. In this study, the changes in maritime traffic density in Korea during the first year of the pandemic, starting from March 11, 2020, are examined. Korea's sea area was divided into grid cells, and the length of ship trajectories within each grid cell was calculated to analyze changes in maritime traffic density. Maritime traffic density changes were analyzed for cargo ships, tanker ships, and passenger ships based on specific operating patterns, and traffic density within major ports was also examined. As a result, an increase in traffic density was observed for both cargo and tanker ships. The purpose of this study is to quantitatively analyze changes in maritime traffic density before and during the COVID-19 pandemic, thereby providing basic data for predicting maritime traffic patterns and developing response strategies in similar global crisis situations in the future.
COMPRESSION OF ENGLISH TECHNICAL TEXTS IN THE FIELD OF AEROSPACE ENGINEERING
Authors: Vashchylo Olha , Roman Yevheniia
Published: December 2024

The article explores compression in English scientific and technical texts, defining it as the process of reducing linguistic elements without sacrificing essential information. Compression is a key feature of this genre, where high accuracy, conciseness, and informational density are paramount. Various linguistic levels of compression are analyzed: phonetic, morphological, lexical, and syntactic. At the phonetic level, compression is achieved through reduction, assimilation, dissimilation, elision, and accommodation, enhancing linguistic economy and speeding up information transmission. Morphologically, the main tools include univerbation, abbreviation, compounding, telescoping, and truncation, all of which reduce linguistic elements while preserving informativeness. Lexical compression employs abbreviations, acronyms, specialized terms, compounding, and borrowings, allowing clarity for specialists by eliminating unnecessary explanations. At the syntactic level, compression uses ellipsis, asyndetic constructions, infinitives, participial and gerundial constructions, and syntactic incompleteness to remove redundancies while maintaining semantic integrity. These techniques contribute to efficient language use and increase informational density, essential for conveying complex technical data. The article also outlines various methods for translating compressed syntactic structures, using examples from English scientific and technical texts in the field of aviation engineering. Compression in the translation of English scientific and technical texts into Ukrainian is examined.
ENGLISH MEDICAL METAPHORS DENOTING MENTAL DISORDERS AND THEIR RENDERING IN UKRAINIAN
Authors: Rudenko Kateryna
Published: December 2024

The article examines the concept and classification of metaphors in medical terminology, substantiating the features of using medical metaphors to denote mental disorders. The study aims to clarify the role of metaphors in shaping public perception of mental disorders and to analyze the sources and methods of collecting English medical metaphors, further identifying typical English metaphorical expressions related to mental disorders. The functions of English medical metaphors and their impact on the sociocultural context are revealed, and the influence of translating such metaphors on the Ukrainian public perception of mental disorders is established. The scientific novelty of the work lies in the systematic study of English medical metaphors and the specificity of their rendering in Ukrainian. This research represents the first comprehensive analysis of translation strategies for conveying mental health metaphors, considering cultural and linguistic differences between English and Ukrainian. The study’s findings contribute to a deeper understanding of cultural influences on the translation process of medical texts and can be used to improve training methods for medical translators. The practical significance of the work lies in the applicability of the results for improving medical translation practices in mental health. The developed recommendations may be useful for professional translators, educators, students, and medical practitioners working with English-language texts. Furthermore, the research findings may enhance communication between healthcare providers and patients from diverse cultural backgrounds, ensuring a more accurate and comprehensible delivery of medical information.
RENDERING THE SEMANTICS OF AMERICAN SLANG VOCABULARY INTO UKRAINIAN
Authors: Gudmanian Artur , Yushkov Ihor , Baklan Iryna
Published: December 2024

The article focuses on the problem of reproduction of American slang lexemes in the Ukrainian language. The authors analyze various definitions of the term “slang”, emphasizing American slang vocabulary. The major translation methods and approaches used to convey the meaning of American slang vocabulary adequately in the Ukrainian language are identified. The challenges that a translator faces in the process of conveying the semantics of slang vocabulary are considered. The examples of reproduction of American slang vocabulary in Ukrainian are analyzed. As a result of the study, recommendations are offered on the most appropriate methods and approaches to translating slang lexemes, which will improve understanding between speakers of different language cultures. The importance of slang as a means of communication within the social environment is emphasized. In order to reproduce American slang vocabulary accurately in translation, it is necessary to take into account not only linguistic aspects but also the cultural contexts of the original text, which allows maintaining the communicative value and accuracy in the process of transferring the meaning. The article reveals how changes occur in the process of translation not only at the lexical but also at the grammatical level, which allows maintaining the emotional coloring and communicative function of the source text. The article presents statistical data that highlights the frequency of application of methods and approaches for slang vocabulary translating. The results of the study are presented in the form of an English-Ukrainian glossary of American slang.
Some features satellite attitude control using quaternions
Authors: Meleshko Vladyslav , Tarnavskyi Sergii
Published: December 2024

Algorithms using the kinematics equations in quaternions are widely used in the attitude control systems of modern spacecraft, primarily microsatellites. They ensure large-angle rotations and avoidance of singularity points characteristic of Euler-Krylov angles. However, the specificity of single quaternions as attitude representation parameters can create an "unwinding effect" in the control system, when turning the spacecraft to a desirable position is not performed by the shortest path and increases the electricity consumption, that is limited on board. This work, summarizing known publications, illustrates the causes of this effect and demonstrates a simple algorithm for its prevention. The effectiveness of this approach is shown on the MATLAB platform numerical simulation examples of the microsatellite control system with reaction wheels and a PD controller.
Часопис «Руслан» як джерело вивчення української еміграції до Бразилії наприкінці ХІХ — на початку ХХ ст.
Authors: Кліш А. , Ігнатенко Н.
Published: December 2024

Дана наукова стаття присвячена аналізу часопису «Руслан» як важливого джерела для вивчення української еміграції до Бразилії наприкінці XIX — на початку XX ст. Часопис «Руслан» був унікальним форумом для спілкування та обміну інформацією між українською громадою в Бразилії та Галичиною. Через свої статті, листи читачів, аналітичні матеріали та інші рубрики «Руслан» надавав можливість отримати унікальний погляд на соціальний, культурний та економічний контекст, у якому функціонувала українська діаспора.
У статті розглядаються такі аспекти, як мотивації еміграції українців до Бразилії, адаптація до нового середовища, проблеми та виклики, з якими вони стикалися, а також їхній внесок у розвиток бразильського суспільства. Автори аналізують різноманітні аспекти життя української громади, зокрема їхню участь у громадських та політичних процесах, збереження культурної спадщини, створення соціальних і освітніх установ, а також взаємодію з іншими етнічними групами.
У часописі описані конфлікти та непорозуміння між різними етнічними та релігійними групами в поселеннях емігрантів у Бразилії наприкінці XIX — на початку XX ст. Зокрема, українські емігранти зазнавали дискримінації та переслідувань з боку польської спільноти. Польське католицьке духовенство та чиновники виявляли ворожість до українців, застосовуючи різні методи, такі як фізичне насильство, ідеологічна пропаганда та заборона будівництва українських церков і шкіл. Українські священики стикалися з неприязню польських духовних лідерів.
Українська громада демонструвала рішучість і вміння відстоювати свої права та інтереси. Вони активно будували церкви та організовували релігійні обряди, навіть без дозволу місцевої влади. Це свідчить про сильну віру та національну свідомість українських емігрантів, які залишали батьківщину в пошуках кращого життя в інших країнах.
МІЖНАРОДНА АКТИВНІСТЬ СЛОВАЦЬКОЇ ПОЛІТИЧНОЇ ЕМІГРАЦІЇ НА ЗАХОДІ (1945 — ЛЮТИЙ 1947 рр.)
Authors: Боровець І.
Published: December 2024

Ліквідація 1945 р. Словацької держави зумовила еміграцію на Захід її очільників та активістів. Спираючись на принцип національного самовизначення, вони обґрунтовували право збереження незалежної Словаччини шляхом вільного плебісциту, зверталися до міжнародних організацій та західних політиків, підтримували ідею інтеграції Центрально-Східної Європи зі Словаччиною як рівноправним членом.
АФГАНСЬКА ВІЙНА СРСР (1979–1989) НА СТОРІНКАХ ПЕРІОДИЧНИХ ВИДАНЬ ОРГАНІЗАЦІЇ УКРАЇНСЬКИХ НАЦІОНАЛІСТІВ (РЕВОЛЮЦІЙНОЇ)
Authors: Ковальков О. , Куценко О.
Published: December 2024

У статті досліджено висвітлення війни СРСР в Афганістані на сторінках газети «Шлях перемоги» й журналу «Визвольний шлях», а також використання афганського питання з боку європейських осередків Організації Українських Націоналістів (революційної) в політичній антирадянській діяльності. Джерельну базу дослідження становили публікації в газеті «Шлях перемоги» та журналі «Визвольний шлях», які датуються 1980–1989 рр. й були присвячені різним аспектам афганської війни або висвітлювали практичну діяльність ОУН (р) і Антибільшовистського Блоку Народів у зв’язку з нею.
З’ясовано, що звернення до афганської війни на сторінках періодичних видань організацій української політичної еміграції було цілком логічним з погляду на їхню націоналістичну і водночас антирадянську спрямованість. Численніші публікації в «Шляху перемоги» на афганську тематику можна умовно поділити на три групи: 1) інформаційні повідомлення, переважно невеликі за обсягом, про війну в Афганістані; 2) різні за обсягом матеріали, які висвітлювали використання афганського чинника в політичній діяльності ОУН (р) та АБН; 3) аналітичні публікації, зазвичай великі за обсягом, присвячені різним аспектам тієї війни. До останньої групи можна віднести статті у «Визвольному шляху». В цих публікаціях Афганістан тлумачився як черговий злочин Кремля, афганці — так само підневільний Москві народ, як українці в СРСР, і перемога афганських повстанців мала наблизити крах «імперії зла», а з нею — незалежність України. Попри заідеологізованість публікацій, їх емоційний і ворожий щодо СРСР стиль слід констатувати високий фаховий рівень української еміграційної журналістики. Більшість наведених у проаналізованих публікаціях фактів відповідають сучасним даним, а теоретичні й аналітичні висновки — адекватні тогочасним оцінкам західних експертів і науковців. Тож «Шлях перемоги» та «Визвольний шлях» транслювали тодішній західний погляд на афганську проблему, проте використовували її в інтересах українського визвольного руху.
The influence of sunflower nanocellulose on the quality indicators of moisture-resistant packaging cardboard
Authors: Barbash Valerii , Yakymenko Olha , Berezovskyi Hlib , Yaschenko Olga
Published: December 2024

There is a steady trend in the world to increase the production of packaging cardboard and paper materials, in particular moisture-resistant container cardboard, which is intended for packaging chilled and frozen products. At the same time, the technology for producing moisture-resistant container cardboard uses chemical additives (CDA), which are usually synthesized from exhaustible energy sources (oil, gas, coal), which pollute the environment and harm human health. An alternative to environmentally harmful CDA are natural biodegradable materials, which include nanocellulose (NC). NC has unique properties and great potential for application in various industries, in particular for improving the performance of paper and cardboard. The paper presents the results of research into the processes of obtaining cellulose and nanocellulose from sunflower stems and the influence of nanocellulose on the quality indicators of moisture-resistant cardboard. The chemical composition and morphological structure of the woody part and parenchyma of sunflower stems were determined. Changes in the yield, residual lignin content and mineral substances in cellulose during the thermochemical treatment of sunflower stalks by extraction with alkali and peracetic solution are presented. The influence of technological parameters of the process of hydrolysis of organosolvent sunflower cellulose on the quality indicators of nanocellulose (NC) is studied. It was established that sunflower NC particles have a transverse size of 6–20 nm, a length of tens of micrometers, the NC suspension has a density of up to 1.51 g/cm³, and NC films have a tensile strength of up to 65.4 MPa, transparency of up to 83%, a crystallinity index of up to 78.4% and a lateral order index of up to 1.83. The influence of sunflower NC on the quality indicators of moisture-resistant container cardboard is studied. It has been established that increasing the consumption of NC in the range from 1 to 5 kg/t of cardboard has a positive effect on its quality indicators, in particular on mechanical strength and water resistance. The use of sunflower NC in the composition of moisture-resistant cardboard allows replacing 50% of environmentally harmful synthetic chemical auxiliary substances used in the production of paper and cardboard.
Evaluation of the efficiency of inhibitor protection of metal surfaces in aggressive water and oil environments
Authors: Kosmyna Mykola , Nosachova Yuliia , Shabliy Tetyana
Published: December 2024

The article analyzes the problems associated with the occurrence of corrosion processes of equipment during oil and gas production. The main anti-corrosion methods and means used in modern conditions are considered.
In the vast majority of cases, the corrosion of industrial equipment proceeds by an electrochemical mechanism when the metal is in contact with an aqueous mineralized environment, therefore it is advisable to use the inhibitory protection of the equipment against corrosion processes. It is known that corrosion inhibitors are substances, the introduction of which in relatively small quantities into an aggressive environment causes a noticeable slowing down of metal corrosion. In fact, it is a substance that inhibits the corrosion process due to competitive adsorption with particles of activators and the formation of protective adsorption or phase films on the metal surface, sometimes with barrier properties. Corrosion inhibitors affect the kinetics of electrode processes that occur during corrosion, and are also characterized by the ability to form oxide, hydroxide or other films on the metal and transfer the metal to a passive state.
Taking into account the mechanism and conditions of corrosion processes during the extraction and transportation of oil-containing products and gas condensate, a chemical method of equipment protection was chosen for research.
Known inhibitors based on phosphonic acids, as well as synthesized substances based on sulfonates, imidazolines, and diamines, were used as chemical agents in the research.
As a result of the research, the effectiveness of protecting metals from corrosion was evaluated depending on the composition of the highly mineralized environment, the type of metal, the type of inhibitor and its concentration, and the effectiveness of the developed scale stabilizer (sodium nitrile dimethyl sulfonate) was evaluated in comparison with known reagents.
It is shown that the effectiveness of protecting metals from corrosion in water-oil mixtures using alkylimidazoline inhibitors and inhibitors developed on the basis of sunflower oil and polyalkylene polyamine (AC-1), ethylenediamine (AC-2) reaches 90% in doses of 5 - 50 mg/dm3.
Neural network model for autonomous navigation of a water drone
Authors: Chekmezov Hlib , Molchanov Oleksii
Published: December 2024

Water drones have significant potential for use in environmental monitoring, search and rescue operations, and marine infrastructure inspection, but the specific conditions of the water environment make it difficult to implement stable autonomous navigation.
The object of research presented in this paper is the machine learning process for autonomous navigation of a water drone model in a simulated water environment. The purpose of the study is to implement a neural network model for autonomous navigation of a water drone using a reinforcement learning method that provides improved obstacle avoidance and adaptation to water currents.
To achieve this purpose, a new neural network model for autonomous drone navigation in the water environment based on the reinforcement learning method is proposed, which differs from the existing ones in that it uses an improved drone control algorithm that takes into account the speed and direction of the water current, which makes it possible to stabilize the process of generating neural network coefficients.
To ensure an effective learning process and optimization of the model, a simulation training environment was developed using the USVSim simulator, which contains various factors that interfere with the drone's movement, such as water current and the presence of other objects. The water drone, acting as an agent, gradually learns to choose the most effective actions to maximize positive rewards through trial and error, interacting with the environment and adapting to changing conditions. This process takes place through the use of a Deep Q-Network: the drone provides the value of its current state to a deep neural network; the neural network processes the data, predicts the value of the most effective action, and gives it to the agent. The current state of the drone is information in the form of a set of sensor readings measuring the distance to the nearest obstacles, drone’s heading and current distance to goal. The value of the effective action received from the neural network is converted into a command for the rudder that the drone can understand. The value of the drone's thruster power is calculated by separate formulas using trigonometric functions.
The results of the study showed that the use of the proposed model allows the drone to make decisions in a dynamic water environment when rapid adaptation to changes is required. The model successfully adapted its strategy based on feedback from the environment, so it can be concluded that the implemented model shows significant potential for further research and applications in the field of autonomous water drones, especially in changing and unpredictable environments.
Dynamic mathematical model for resource management and scheduling in cloud computing environments
Authors: Kovalenko Vladyslav , Zhdanova Olena
Published: December 2024

The object of the research is resource management and scheduling in Kubernetes clusters, in particular, data centers. It was determined that in many publications dedicated to optimization models of scheduling for Kubernetes, mathematical models either do not include constraints at all, or only have the constraints determined on the high level only. The purpose of the research is the creation of a dynamic low-level mathematical optimization model for resource management and scheduling in cloud computing environments that utilize Kubernetes. Examples of such environments include the data centers where the customers can rent both dedicated servers and resources of shared hosting servers that are allocated on demand. The suggested model was created using the principles of creation of mathematical models of discrete (combinatorial) optimization, and was given the name “dynamic” because it takes the time parameter into account.
The model receives data about individual servers in the cluster and individual pods that should be launched as an input. The model aims to regulate not only individual assignments of pods to nodes, but also turning on and off the servers. The model has objectives of: minimization of the average number of shared hosting servers running; maximization of the average resource utilization coefficient on such servers; minimization of the number of occasions when the servers are turned on and off; minimization of resource utilization by the pods that are running on shared hosting servers but created by the customers renting the dedicated servers. The model considers resource constraints, among other limitations.
A method and software for license plate recognition
Authors: Yakovlev Anton , Lisovychenko Oleh
Published: December 2024

В статті представлений метод розпізнавання номерних знаків із використанням сегментації шляхом використання системи детектування YOLO у поєднанні із завдання-орієнтованим підходом до процесу навчання та використанням масивів варіативних даних реального світу.
Розвиток мегаполісів і постійне збільшення кількості транспортних засобів на дорогах призвели до нового рівня вимог до систем безпеки дорожнього руху. Автоматизація, без перебільшення, є найбільш пріоритетним напрямком розвитку цих систем. Лише за допомогою автоматизації системи безпеки дорожнього руху можуть обробляти величезну кількість інформації, що генерується на дорогах щодня. Крім того, автоматизація дозволяє поступово зменшувати участь людини в задачах, які обчислювальні системи можуть виконувати з еквівалентною або більшою точністю. Ці досягнення спрямовані на мінімізацію впливу людського фактору, а також на зниження експлуатаційних витрат. Це особливо важливо для мегаполісів, але також стосується транспортної системи в цілому.
Метою дослідження є розробка методу автоматизованого розпізнавання номерних знаків для підвищення точності систем забезпечення дорожньої безпеки шляхом зниження рівня помилок, мінімізації надмірного використання обчислювальних ресурсів у процесі виявлення та здешевлення таких систем. Об’єктом дослідження є процес розробки автоматизованих програмних систем для забезпечення дорожньої безпеки з інтеграцією функціоналу ідентифікації транспортних засобів.
Для досягнення поставленої мети були визначені такі завдання: розробити метод розпізнавання номерних знаків із застосуванням цілеспрямованого підходу до навчання у поєднанні з системою виявлення YOLO; оцінити вплив попередньої сегментації номерних знаків із використанням спеціально навченої системи YOLO на рівень помилок і часові витрати, а також провести експерименти із застосуванням запропонованого методу навчання на реальних зображеннях із варіативним довкіллям для підтвердження його адекватності.
Порівняльний аналіз використання завдання-орієнтованого методу навчання системи детектування на базі YOLO v5 лише з загальноприйнятим методом оптичного розпізнавання символів (Optical Character Recognition, OCR) підтвердив переваги завданняорієнтованого методу при вирішенні завдання з розпізнавання номерних знаків. Також було досліджено вплив розмиття на результати детектування із використанням OCR методу.
Результати практичних досліджень підтверджують правильність обраних методів для підвищення ефективності розпізнавання номерних знаків.
Depth-Width type criteria approbation for tree shape control for the Monte Carlo Tree search method
Authors: Marchenko Oleksandr , Marchenko Oleksii
Published: December 2024

This paper is devoted to the scientific problem of improvements of the Monte Carlo Tree Search (MCTS) method. The object of research is the process of performing a tree search using the MCTS. The subject of research is the MCST improvement technique with control of the search tree shape by usage of the previously proposed be the authors DWC (Depth/Width Criterion) and WDC (Width/Depth Criterion) criteria. This technique was named Monte Carlo Tree Search with Tree Shape Control (MCTS-TSC). The research methods are based on the theory of data structures and analysis methods.
The aim of the study is to conduct extended study of the previously proposed MCTS-TSC technique for improvement of the MCTS method. In particular, the aim is to approve that the DWC and WDC tree shape control criteria ensure the better move selection and increasing player strength compared to the standard Monte Carlo Tree Search with Upper Confidence bounds applied to Trees (MCTS-UCT) technique.
To achieve the aim, the following tasks were set: to conduct a set of experiments according to the developed approbation methodology to approve that the WDC criterion of the MCTS-TSC technique is able to improve the MCTS method; to conduct a set of experiments according to the developed approbation methodology to approve that the DWC criterion of the MCTS-TSC technique is able to improve the MCTS method.
Both WDC and DWC criteria of the MCTS-TSC technique were tested on a series of games of Connect Four between a player, which used the MCTS-TSC technique, and a player which used the MCTS-UCT technique. Different parameters for tuning the formulas of the WDC and DWC criteria of the MCTS-TSC technique were used in the experiments.
The paper describes the methodology of the approbation of the MCTS-TSC technique with usage of the WDC and DWC criteria compared to the MCTS-UCT technique and conducts comparative analysis of the results of the experiments. The MCTS-TSC player won from 30% to 70% more games than the MCTS-UCT player for some search tree shapes, when WDC criterion was used, and from 19% to 52% more games, when DWC criterion was used. So, ability of the proposedMCTS-TSC technique to improve the MCTS method was approved for both criteria, WDC and DWC.
Key words: depth-width type criteria, Monte Carlo tree search method, MCTS, MCTS-UCT, MCTS-TSC, search tree shape control.
The Role of Urban Design in Facilitating a Circular Economy: From Linear to Regenerative Cities
Authors: Munonye Williams Chibueze , Ajonye George Oche
Published: December 2024

The increasing urbanization of cities worldwide has driven a parallel rise in resource consumption, waste generation, and environmental degradation. The transition to a circular economy (C.E.) offers a sustainable alternative, shifting from traditional linear resource use and disposal systems to regenerative systems prioritizing material reuse, resource efficiency, and ecological restoration. Urban design and planning are essential in facilitating this shift by creating the physical and regulatory infrastructure necessary to implement C.E. principles in cities. This paper explores the role of urban design in promoting circular economy strategies, focusing on adaptive reuse of buildings, green architecture, and integrating nature-based solutions (NBS) into urban environments. Through detailed analysis of these strategies and case studies from cities worldwide, this paper demonstrates that regenerative design is essential for closing material and resource loops and creating more sustainable, resilient cities.
Deep Learning and Reinforcement Learning for Assessing and Enhancing Academic Performance in University Students. A Scoping Review
Authors: Stasolla Fabrizio , Zullo Antonio , Maniglio Roberto , Passaro Anna , Di Gioia Mariacarla , Curcio Enza , Martini Elvira
Published: December 2024

Background: University students may encounter challenges throughout their academic careers, with an increased risk of academic drop-out.Among new technologies, those based on Artificial Intelligence (AI), such as Deep Learning (DL) and Reinforcement Learning (RL) strategies, have emerged as valuable resources to assess and enhance academic performance.
Objectives: To evaluate the effects DL and RL AI-based strategies for assessing and enhancing academic performance in university students.
Method: A scoping review on the use of DL and RL AI-based strategies for assessing and enhancing academic performance was carried out. A literature overview on the newest empirical studies was conducted.
Results: Recent studies were reviewed. Data were encouraging and promising. Strengths and weaknesses of DL and RL AI-based strategies in were critically discussed.
Conclusions: DL and RL AI-based strategies are effective for assessing and improving academic performance. The limitations of the analyzed studies were examined, and some useful insights for future research were highlighted.
Molecular Dynamics Simulation Study on the Influence of Twin Spacing and Temperature on the Deformation Behavior of Nanotwinned AgPd Alloy
Authors: Zhang Wanxuan , Zhao Kangkang , Shan Shuang , Chen Fuyi
Published: December 2024

The effect of twin spacing and temperature on the mechanical behavior and deformation mechanism of nanotwinned AgPd alloy is investigated by molecular dynamics simulation. It is found that the nanotwinned AgPd alloy with small grain size shows a strengthening-softening transition with the reduction of twin spacing, which is attributed to the transition of dislocation from inclined to twin boundaries (TBs) to parallel to TBs. However, the nanotwinned AgPd alloy with large grain size shows a continuous strengthening with the decrease of twin spacing. It originates from the strain localization in grain boundaries and few dislocations are activated in the tensile processes. Lower temperatures increase the stability of preset twins and the formation of new twins, while higher temperatures promote atomic motion and migration of grain and twin boundaries, further exacerbating "detwinning."
Research on Simulation Optimization of MEMS Microfluidic Structures at the Microscale
Authors: Wang Changhu , Meng Weiyun
Published: December 2024

Abstract: Microfluidic systems have become a hot topic in Micro-Electro-Mechanical System (MEMS) research, with micropumps serving as a key element due to their role in determining structural and flow dynamics within these systems. This study aims to analyze the influence of different structural obstacles within microfluidics on micropump efficiency and to offer guidance for improving microfluidic system designs. In this context, a MEMS-based micropump valve structure was developed, and simulations were conducted to examine the effects of the valve on microfluidic oscillations. The research explored various configurations, including valve positions and quantities, yielding valuable insights for optimizing microfluidic transport mechanisms at the microscale.
Environmental, Social and Governance (ESG) Score and Corporate financial performance: Evidence from the Nigerian Market
Authors: Oyegunle-Esimaje Cynthia
Published: December 2024

This study investigated the impact of ESG score on the Corporate financial performance of non-financial firms (NFFs) listed in the Nigerian exchange group. In this study disclosure of ESG is considered and quantified using sentence counting (ESG Score) and financial performance is measured by Return on Assets (ROA), Return on Equity (ROE) and Book Value to Equity (BTE) which is a combination of accounting and market-based variables.Findings of the study revealed that the relationship between ESG score and Corporate financial performance in Nigerian’s non-financial firms (NFFs) has a wide landscape. The positive correlations observed between ESG score and ROA/ROE signified the potential for favorable financial outcomes associated with heightened ESG engagement. However, the unexpected negative association between ESG score and BTE introduced complexity to the relationship, indicating a potential trade-off with financial leverage. The implication of these findings is that Nigerian’s non-financial firms need to navigate the incorporation of ESG initiatives judiciously. While reaping potential benefits in terms of ROA and ROE, NFFs should carefully consider the impact it has on financial leverage. This necessitates a strategic approach that balances the social responsibility agenda with the optimization of financial structures. The study recommends NFFs to establish mechanisms for continuous monitoring and evaluation of the impact of ESG practices on various financial indicators. This involves regularly assessing the outcomes of ESG initiatives and making adjustments to ensure they are not mere diversion of companies’ resources.
Could Renal Vascular Variations Be Associated with Resistant Hypertension: A Single-Center Study
Authors: Naydenov Stefan Naydenov , Jekova Margarita , Manov Emil , Runev Nikolay
Published: December 2024

Background: Anatomical variations in renal vessels are common in humans. However, the clinical significance of these congenital vascular abnormalities remains incompletely understood. This study aimed to assess the prevalence and characteristics of renal vascular variants in patients with arterial hypertension (HTN) and their association with the development of resistant HTN. Methods: We screened 3,762 consecutive hypertensive patients hospitalized in our clinic and identified 128 (3.4%) with resistant HTN. These patients were matched with 128 hospitalized patients with controlled HTN. All participants underwent contrast-enhanced computed tomography imaging of the kidneys, including renovasography. Results: Anatomical renal vascular variations were identified in 64 (25%) of the 256 participants: 49 (38.3%) of the 128 patients with resistant HTN and 15 (11.7%) of the 128 patients with controlled HTN (p < 0.001). Among patients with renal vascular abnormalities, 76.6% had resistant HTN, while 23.4% had controlled HTN (p < 0.001). Regression analysis demonstrated a strong association between the presence of renal vascular variants and the development of resistant HTN, with an odds ratio of 4.67. Conclusions: Anatomical renal vascular variations were found to be common among hypertensive patients in this study and were strongly associated with the development of treatmentresistant HTN.
Technologies for Fabricating Large Aperture Diffraction Gratings
Authors: Shao Changfeng , Li Xinghui
Published: December 2024

Large diffraction gratings have played an important role in modern scientific fields such as inertial confinement fusion, large-aperture astronomical telescopes, and high-precision immersion lithography machines with long-stroke displacement stages. However, due to the large size and high accuracy requirements of gratings, and considering the high efficiency and low cost, the fabrication of large gratings is extremely difficult. This paper reviews the fabrication technologies for large diffraction gratings, including the grating tiling technology, the grating ruling technology, the single exposure lithography, the optical mosaic grating technology, and the scanning beam interference lithography. It introduces the basic principles, representative research, and research progress of these technologies, analyzes their advantages and current problems, and provides reference for the development and optimization of the fabrication technologies of large diffraction gratings.
Impact of Emission Standards on PM2.5 Toxicity: A Long-Term Analysis in Los Angeles
Authors: Badami Mohammad Mahdi , Aghaei Yashar , Sioutas Constantinos
Published: December 2024

This study investigates long-term trends in fine particulate matter (PM2.5) composition and oxidative potential in Los Angeles. While regulatory interventions have reduced PM2.5 mass concentration and primary combustion-related components (e.g., organic carbon (OC) and elemental carbon (EC)), our findings reveal a more complex PM2.5 toxicity pattern. From 2001–2008, PM2.5 oxidative potential, measured via the dithiothreitol (DTT) assay, declined from ~0.84 to ~0.16 nmol/min/m3, coinciding with stringent tailpipe emission controls. However, after this initial decline, PM2.5 DTT stabilized and gradually rose from ~0.35 in 2012 to ~0.97 nmol/min/m3 by 2024, reflecting a shift in PM2.5 composition toward non-tailpipe emissions’ tracers, and the growing importance of their sources, such as brake/tire wear. Metals and trace elements, such as iron (Fe, ~150 ng/m3) and zinc (Zn, ~10 ng/m3), remained relatively stable as OC and EC declined, resulting in non-tailpipe contributions dominating PM2.5 toxicity. Although PM2.5 mass concentrations were effectively reduced, the growing contribution of non-tailpipe emissions (e.g., brake/tire wear and secondary organic aerosols) to PM2.5 toxicity underscores the limitations of mass-based standards and tailpipe-focused strategies. Our findings emphasize the need to broaden regulatory strategies, targeting emerging sources that shape PM2.5 composition and toxicity, and ensuring more meaningful improvements in public health outcomes.
Techno-Economic Optimization of Hydrogen-Based Hybrid Renewable Energy Systems for Rural Electrification in Sub-Saharan Africa: Case Study of a Photovoltaic/Wind/Hydrogen System in Dargalla, Cameroon
Authors: Yimen Nasser , Mondoue Bouodo Thierry Roger , Biboum Alain Christian , Nzotcha Urbain , Musa Bashir , Djomi Rolland , Sani Salisu
Published: December 2024

Hybrid renewable energy systems (HRESs) are an effective tool for addressing the challenges of rural electrification in sub-Saharan Africa (SSA). However, their viability is limited by the lifespan, environmental impacts, high costs, and inefficiency of conventional energy storage technologies (battery and pumped-hydro). This study examines a hydrogen-based energy storage system, combined with photovoltaic (PV) and wind energy, for the electrification of Dargalla, a village in northern Cameroon. The goal is to meet community and agricultural electricity needs while optimising the system. The analysis utilised HOMER software to simulate, model, and optimise the system. The optimal architecture included a 50-kW PV array, a 10-kW wind turbine, a 1-kW fuel cell, a 30-kW electrolyser, a 25-kg hydrogen tank, and a 10-kW converter. The optimised system's net present cost and cost of energy were assessed at USD 138,202 and USD 0.443/kWh, respectively. Sensitivity analysis results showed that areas with high wind speeds would be mainly suitable for the proposed system. Moreover, with the upcoming decrease in the costs of fuel cells and PV components, such systems are expected to become more economically viable in the future, leading to the conclusion that integration of hydrogen-based energy storage technology in HRESs in SSA can effectively address the United Nations Sustainable Development Goals (UNSDG) and the historic Paris Climate Agreement (HCA).
Desafios pedagógicos e estruturais para o ensino do conceito de fronteira na educação básica
Authors: Tonin Juliana , Rocha Marcelo Augusto
Published: December 2024

Investigou-se as práticas e saberes docentes de um grupo de professores de geografia do ensino fundamental que lecionam na fronteira trinacional, entre Brasil, Paraguai e Argentina, na região de Foz do Iguaçu - Paraná. Buscou-se analisar ainda, como esses professores trabalham o conceito de fronteira com seus alunos, identificando, quais estratégias e recursos didáticos empregam em suas aulas para este fim. Ao buscar compreender as relações que permeiam o ensino do conceito de fronteira, a pesquisa procurou dialogar com a visão e a experiência dos professores entrevistados que residem e vivenciam a fronteira trinacional. A aplicação do questionário se deu por meio Google Formulários, a partir da técnica de coleta de dados conhecida como “Bola de Neve”. Entre os resultados alcançados, destaca-se haver certa polissemia acerca do entendimento e da profundidade do conceito de fronteira entre os professores entrevistados. O material didático mais utilizado é o mapa, seguido de perto pelo livro didático. Entre o uso das mídias digitais, destacam-se vídeos do Youtube, apresentações de Power Point e documentários.
Role of Growth Regulators and Plant Media on Growth and Yields of Mint
Authors: Sulandjari Sulandjari , Pujiasmanto Bambang , Supriyono Supriyono , Harsono Puji , Fajrin Nurin Adyanisa
Published: December 2024

There is a significant industrial demand for products produced by the mint plant (Mentha piperita L.), yet Indonesia cannot meet all of that need. One of the efforts to increase mint plant production is using manure and atonic growth regulators in the right concentration. The method used was a Factorial Randomized Complete Block Design (RCBD) with two factors. The first factor was the composition of the planting media (soil: husk charcoal, soil: husk charcoal; cow manure, soil: husk charcoal: goat manure, soil: husk charcoal: chicken manure, with a ratio of 1: each: 1:1). The second factor was the atonic concentration (0, 1, 2, 3 mL.L-1). The results showed that using chicken manure gave the best results for growth and yield. Atonic administration with a concentration of 2.05 mL.L-1 gave optimum results on the fresh weight of roots, and a concentration of 2,06 mL.L-1 gave optimum results on the dry weight of roots. The combination of the two treatments did not significantly affect the observed variables.
Persentase Keberhasilan Persilangan Full Diallel beberapa Genotipe Cabai Rawit (Capsicum frutescens) dan Keragaman Fenotipe Karakter Buahnya
Authors: Zulfahmi Zulfahmi , Gusrinaldi Gusrinaldi , Mirdhayati Irdha , Rosmaina Rosmaina
Published: December 2024

Genetic expansion of plants can be done by crossing between plant genotypes. This research aims to determine the percentage of successful chili crosses using the full diallel method and determine the level of phenotypic diversity resulting from the crosses. This research used five cayenne pepper genotypes, viz. UIN-041, UIN-048, UIN-050, UIN-062, and UIN-063. The crossing of the five genotypes was carried out using the full diallel method. The parameters observed consisted of the percentage of successful crossing, fruit weight, fruit diameter, fruit length, and number of seeds. The data obtained were subjected to analysis of variance and calculation of the phenotypic diversity coefficient for each character. The results of this study showed that the percentage of successful crossing ranged from 15.00 - 43.30%. The highest value was observed in crossing UIN-041 x UIN-050 and the lowest in UIN-062 x UIN-048. The low successful percentage of crossing is influenced by the pollen condition of the male parents and the level of cross-compatibility. The phenotypic variability value of the fruit weight and fruit length characters was 0.48 and 1.50, respectively, and that was classified as narrow variability, while the fruit diameter and fruit number characters were 5.23 and 120.34, respectively, and classified as broad variability.
Calculation of the winding data of the on and off coils of a bistable polarized electromagnet for a vacuum medium voltage contactor
Authors: Leliuk Mykola , Sereda Oleksandr , Sereda Olena , Lytvynenko Victoriia
Published: December 2024

Medium voltage vacuum contactors consist of switching and drive modules. When developing or improving the designs of contactors, the switching module must meet the requirements set forth by their manufacturers. In accordance with these requirements, a drive module is being developed, which consists of a mechanical system and an electromagnet. The operation of the mechanical system of the contactor depends on correctly selected contact springs, and the operation of the electromagnet depends on traction forces during switching operations. The design of a vacuum contactor with a bistable polarized electromagnet with two ON and OFF coils is considered in the article. The counteracting characteristic of the mechanical system of the contactor is constructed and the forces acting on the electromagnet in the ON and OFF positions of the contactor are determined. The FEMM model of a bistable polarized electromagnet was developed and the minimum MMF value of the ON and OFF windings was determined. The resulting traction characteristic of a bistable polarized electromagnet is constructed at the minimum MMF value of the ON and OFF winding sand the working gap. It was determined that when performing the switching operation and using the ON and OFF winding at the same time, it was possible to reduce the MMF of the electromagnet operation. The winding data of the ON and OFF coils were calculated at different values of the nominal diameter of the wire and the voltage of the power supply network, and, in accordance with this, the minimum value of the MMF of the windings was determined
The importance of the concept of sustainable development in the activities of energy companies
Authors: Pantielieieva Iryna , Varshamova Iryna , Lytvynenko Victoriia
Published: December 2024

Sustainable development of energy enterprises is aimed at consistent transformations that ensure effective and sustainable development of the country's energy sector. It covers sustainable changes in industries and enterprises of the fuel and energy complex, which plays a key systemic role. The article analyzes the activities of energy sector enterprises and identifies their specifics in the context of achieving sustainable development goals. The purpose of this article is to study the essence of sustainable development of the energy sector and analyze methodological approaches to its assessment. The concept of "sustainable energy development" is considered at three levels: state, sectoral and at the level of energy enterprises. The authors offer their own vision of sustainable energy development for each of these levels. The article also analyzes methodological approaches used in world practice to assess sustainable energy development, focusing exclusively on the state level. The following methods were used in the study: analysis and synthesis - for a detailed study of the basic principles of the functioning of the energy sector; induction and deduction - for an in-depth analysis of the features of its activities in the context of achieving sustainable development goals. In addition, a graphical method was used, which allows us to clearly present the results obtained and demonstrate the key conclusions of the study. The combination of these approaches ensures the complexity and structure of the analysis. It was found that sustainability is inherent in such systems that, under the influence of external and internal factors, retain their basic characteristics and properties. To eliminate imbalances in development and achieve proportionality, the structure of the system must be flexible, adaptive and have the potential for continuous improvement. An important role in ensuring the sustainability and integrity of the energy system is played by the integration and interdependence of its elements, as well as their ability to effectively self-regulate.