bluuebunny/crossref_metadata_2025 huggingface dataset:
TERMINOLOGIA DA MATEMÁTICA EM LÍNGUA DE SINAIS BRASILEIRA: PROPOSTA DE GLOSSÁRIO BILÍNGUE LIBRAS PORTUGUÊS
Authors: Rodolpho Pinheiro D’ Azevedo
Published: December 2024

O tema desta dissertação se insere na linha de pesquisa Léxico e Terminologia, desenvolvida no Centro de Estudos Lexicais e Terminológicos (Centro Lexterm) e no Laboratório de Língua de Sinais Brasileira (LabLibras) da Universidade de Brasília. Oobjeto de estudo é constituído pelos termos matemáticos relacionados ao campo conceitual equações, tendo como públicoalvo os alunos Surdos, bem como os professores e intérpretes educacionais atuantes na Educação Básica. O objetivo é criar glossário terminológico bilíngue Libras-Português de termos matemáticos deste campo conceitual. Para tanto, registramos os termos e sinais-termo seguindo o modelo de ficha terminográfica de Faulstich (2010), para a Língua Portuguesa – LP, e o modelo de ficha terminográfica em Libras de Tuxi (2017). O método empregado na pesquisa foi o analítico-descritivo. Como procedimentos metodológicos, adotamos os seguintes percursos: i) coleta dos termos e das definições em LP; ii) reformulação das definições em LP; iii) preenchimento das fichas terminográficas em LP; iv) coleta dos sinais-termo em Libras; v) criação dos sinais-termo; vi) validação dos sinais-termo; vii) preenchimento das fichas de análise de sinal-termo; viii) criação das definições em Libras e ix) preenchimento das fichas terminográficas em Libras. Para o preenchimento das fichas de análise de sinal-termo e das fichas terminográficas em Libras utilizamos QR Code (TUXI, 2017) para disponibilizar a visualização dos sinais-termo, definições, variantes, equivalentes e remissivas por meio de vídeos. Realizamos, ainda, a análise de sete obras terminológicas da matemática com base no roteiro para avaliação de dicionários e glossários científicos e técnicos de Faulstich  (2011). Dentre as obras avaliadas, as línguas contempladas foram português, inglês, Libras, ASL, BSL e LSF. Além disso, analisamos as definições matemáticas contidasnos livros didáticos aprovados pelo PNLD utilizados do 6° Ano do Ensino Fundamental ao Ensino Médio. Essa análise revelou a necessidade de reformulação das definições em língua portuguesa. Como resultado dessa pesquisa, apresentamos o glossário bilíngue Libras – Português da matemática, o qual se baseou na proposta de organização de glossário bilíngue de Tuxi (2017). No glossário bilíngue Libras – Português de matemática são apresentados os 30 verbetes no formato bilíngue Libras – Português de 30 termos e sinais-termo do campo conceitual equação. Ainda, apresentamos a proposta de registro de sinais-termo equivalentes em outras línguas de sinais, além da possibilidade de direcionamento a remissivas, tanto em LP quanto em Libras, por meio de hiperlinks. A contribuição da pesquisa é disponibilizar obra de consulta, direcionada aos alunos Surdos, professores e intérpretes educacionais. Além disso, o modelo de glossário apresentado pode servir para ser aplicado em outros campos conceituais ou a outros domínios do saber.
Change management and employee engagement as a possible turn around strategy
Authors: Khonjelwayo Mthunzi , Ellenson Thandeka
Published: December 2024

The purpose of this study is to explore the concept of change management, and employee engagement as a possible organisational turnaround strategy. This is owing to Organisations exist to deliver their strategic goal and objectives, this would amongst others ensure both technical and tactical strategical success. When organisations strategy is in shape there is a high rate of employee retention and recruitment of the best talent in the market. However, the organisations always faces a conundrum of having to tap in their organisational turnaround strategy which in most cases is marred with resistance from the employees. This study seeks to establish the extent to which change management and employee engagement can be adopted as key organisational turnaround strategy. The study adopts an interpretive qualitative design, and thematic analysis to organize dataset into relevant themes. Study recommends employer consultation and employee participation, facilitation, negotiation and agreement, and manipulation and coercion as a blended approach to effective organizational turnaround strategy. The value of the study is how a simultaneous use of change management and employee engagement can be used by global organizations for effective turnaround strategies.
Influence of inspirational motivation on employee engagement in parastatals in the energy sector in Kenya
Authors: Change Doris
Published: December 2024

The purpose of this study was to investigate the influence of inspirational motivation on employee engagement in parastatals in the energy sector in Kenya. The article was guided by three objectives: the influence of visionary leadership on employee engagement, the influence of communication on employee engagement, and the influence of job autonomy on employee engagement. The target of the study was the 10 parastatals based within the energy sector in Kenya having a population of 315 middle-level managers. The study adopted a positivist research philosophy to examine the influence of inspirational motivation on employee engagement. The data was collected by using structured questionnaires. This study conducted correlational research to determine the strength of the relationship between the parameters of inspirational motivation and employee engagement. The findings of this study showed that employee engagement has a significant statistical relationship with visionary leadership, r(166) = 0.360, p < 0.01; communication, r(166) = 0.387, p < 0.01 and job autonomy, r(166) = 0.439, p < 0.01. Multiple linear regression analysis revealed that inspirational motivation positively and significantly influences employee engagement, R2= .258, F(3, 162) = 18.804, p < .01; ? = 0.428, p < .01. The findings concluded that visionary leadership, communication, and job autonomy positively and significantly influence employee engagement
Corporate social responsibility communication strategies through social media and their influence on e-reputation in Nigeria
Authors: Ekpebu Eneye Ebiweni
Published: December 2024

This study investigates the influence of Corporate Social Responsibility (CSR) communication strategies via social media on corporate e-reputation in Nigeria. In an era where online platforms shape brand perception and consumer behavior, CSR communications have emerged as a vital tool for companies to engage with stakeholders, enhance transparency, and foster trust. The research employs an abductive methodology and systematic literature review (SLR), exploring CSR awareness, consumer responses, and behavioral shifts driven by CSR initiatives communicated on social media. Using online polls and Q&A sessions for data collection, the study analyzes the effectiveness of CSR strategies and their impact on consumer trust, loyalty, and purchasing decisions. Findings reveal that CSR communication through social media significantly enhances e-reputation, positively influencing brand loyalty and consumer perception. The study underscores the importance of transparent and engaging CSR communication in building a strong online reputation, and highlights how visual content, storytelling, and real-time updates can amplify CSR efforts. This research contributes to the understanding of the role of digital communication in shaping corporate e-reputation in Nigeria.
Assessment of users’ skills in managing electronic records management system at Workers Compensation Fund (WCF) Dar Es Salaam, Tanzania
Authors: Maturo Bertha
Published: December 2024

This study assessed users' skill in operating the electronic records management system, specifically concerning the Workers Compensation Fund (WCF). The study specifically examined the training for the electronic records management system, encompassing the types of training offered, their frequency, and the relevance and effectiveness of the training delivered. The study population consisted of all employees at WCF. The study deployed a descriptive research design in conjunction with qualitative and quantitative methodologies. The sample size consisted of 115 respondents. Data were gathered by questionnaires, interviews, and observational methods. Additionally, qualitative data were quantitatively evaluated using IBM-SPSS version 20, along with Microsoft Word and Excel, to ascertain the frequency and percentage of respondents' replies in relation to the study findings. Findings indicated that WCF offers operational training for ERMS, while security and technical training for ERMS staff is conducted annually to enhance employees' abilities and expertise in administering ERMS.  The study indicates that the management of WCF should continue to empower the ICT team to provide comprehensive in-house support. Additionally, negotiate with EGA for a dedicated desk to address their technical difficulties.
Cultural forces shaping social influences: the role of power distance, uncertainty avoidance, and individualism
Authors: Chabika RC , Van Schalkwyk JH , Jansen van Rensburg LR , Muller Re-an
Published: December 2024

The purpose of this paper is to investigate the influence of cultural forces that shape social influence with a look at Hofstede’s cultural dimensions of power distance, uncertainty avoidance, and individualism. The direct effect of these cultural dimensions on social influence is investigated. To measure social influence, this paper relies on the dimensions of Hofstede. A multiple regression analysis is applied to answer the hypotheses. The research design adopted for the research was quantitative, and the method used to collect data was an online survey. A self-administered questionnaire was developed and distributed to the targeted respondents for obtaining primary data.The respondents involved were 340 SMEs in the urban area of Harare province in Zimbabwe. A nonprobability convenience sampling method was used for the study. Hofstede’s cultural factors of power distance, individualism, and uncertainty avoidance were used as the independent variables that moderate social influence.
Critical components enhancing the functionality and performance of contact centre operations
Authors: Mabotja Semakaleng , Mkhomazi Sibongile Sharol
Published: December 2024

Contact centre operations are essential for providing customer support and managing client enquiries. A contact centre, akin to any other business, necessitates numerous essential components. A significant number of these components directly influence the business. Recognising and improving these elements can assist a contact centre in achieving its overarching objectives. The report seeks to analyse the essential elements that improve the efficiency and effectiveness of contact centre operations. The emphasis is on technology, personnel, and processes as the essential elements that enhance the efficient and effective operation of contact centres. The efficacy and efficiency of a contact centre environment encompass personnel, procedures, and technology across all organisational levels. These components must not be considered in isolation, as they influence the success or failure of a contact centre environment. Consequently, comprehending the interaction between these components is of paramount importance.Quantitative data were evaluated with the Statistical Package for the Social Sciences (SPSS). The convenience sample approach was deemed suitable for sampling contact centre agents, team leaders, and managers at the Department of Home Affairs. The study's principal findings indicate that both the literature research and the results highlighted the significance of components in facilitating the functioning and performance of contact centre operations. The data corroborate the idea that numerous contact centre failures stem from the absence of essential components necessary for its operation. The inclusion of suitable components in the contact centre has revolutionised management's oversight of these facilities. The analysis indicates that an effective team inside the company facilitates the management of contact centres. The report advocates for the implementation of integrated technological solutions to expedite customer interactions and improve operational efficiency in contact centres. It is advisable to invest in frequent employee training to ensure that staff are equipped to handle complex enquiries and effectively utilise advanced systems. Optimised process enhancement initiatives, including workflow simplification and decrease of call handling duration, are deemed essential for augmenting functionality.
Function, representativeness and spatial implications of form modelling in Le Corbusier’s architecture
Authors: Gómez-García Alejandro
Published: December 2024

Le Corbusier's design process is structured into two distinct phases when the functional programme is somewhat complex: the first, in which simple volumes capable of housing the building's various uses are chosen, as well as the connections that must be established between them, and the second, of a more intuitive and emotional nature, in which some of them are modelled to achieve artistic and singular forms, with curved geometry, which stand out among those with an orthogonal matrix. In this way, a kind of duality is established, which we could call rationalist-intuitive, which would be added to other already well-known pairings such as, for example, masculinefeminine (Fernández Galiano) or public-private (Colomina).The origin of these artistic forms is in the first villas of La Chaux-de-Fonds where, still with a simple character and clearly indebted to certain episodes in the history of architecture, they appear next to a single main box. From here, in accordance with the successive changes in Le Corbusier's interests, both pictorial and architectural, we see them evolve and take on new meanings and increasingly complex roles in the development of the designs. The influence of cubism and his determined commitment to industry, first and foremost, and then to nature, enabled him to explore the possibilities of a particular formal language with which to compose his works based on this duality of cubic and artistic forms.Following a temporal order, this article studies some of the artistic forms used by Le Corbusier in his architecture, analysing both their functional, spatial, perceptual and representative implications, as well as the way and timing in which they appear, either at the beginning or in an intermediate phase of the ideation process.
HISTÓRIA E MEMÓRIA DA COLONIZAÇÃO DIRIGIDA: OS TRABALHADORES RURAIS E SUAS IDENTIDADES
Authors: Menezes Soares Filipe
Published: December 2024

O artigo a seguir é fruto de pesquisa realizada na Amazônia desde 2015, entre os trabalhos de dissertação e tese. Aqui investiga-se a política de colonização dirigida na Amazônia desde o ano de 1970. Serão analisados depoimentos de antigos colonos que ocuparam as margens da rodovia Transamazônica durante aquele período. São estudos de memória que pretendem demonstrar a importância do tempo presente na conformação dos relatos. Parte importante é intender a situação dos trabalhadores rurais, antigos colonos, nos arredores da cidade de Altamira. Dito de outro modo, recuperar os depoimentos desse conjunto de pessoas é apelar para uma “história vista de baixo”. Contudo, têm-se ciência de que não sou eu quem lhes dá a voz necessária à crítica da política em questão. Ora, são os próprios trabalhadores que optaram por ocupar seu lugar de fala, se posicionando como autoridades quando o assunto é a ditadura na Amazônia. Por fim, pretendo trazer a importância da memória para a conformação de classe dos antigos pioneiros, suas distintas identidades, desembocando na configuração social do território que representa as margens da Transamazônica na contemporaneidade.
MEMÓRIAS, NARRATIVAS E ANCESTRALIDADE DO QUILOMBO SAMBAQUIM
Authors: Xavier Filho José  Luiz
Published: December 2024

O Quilombo Sambaquim, localizado no município de Cupira, pequena cidade do agreste pernambucano, como muitas das comunidades quilombolas da região, sofre com descasos públicos, como por exemplo, a falta de recursos e a desvalorização cultural. Os diálogos aqui inseridos são muito mais valiosos do que mera descrição. São registros históricos de um povo, que por muito tempo foi silenciado pela sociedade da qual faz parte. Nossa função como historiador é levar adiante a pesquisa, tecendo a trajetória histórica dessa comunidade, através de suas memórias, tradições e oralidades. Analisar a comunidade quilombola é fazer uma viagem e se aventurar em suas narrativas, pois, é a através da tradição oral que são preservados os saberes dos seus ancestrais. Logo, o nosso objetivo é construir a história do Quilombo Sambaquim, através da valorização e da apropriação das narrativas contadas pelos membros da comunidade assim como seu legado histórico, fazendo uma analogia entre o seu passado escravista, a história sobre seus antepassados, e o tempo presente da comunidade, tendo em vista as contribuições estabelecidas na construção da identidade e ancestralidade de seus moradores. Entendemos que as tradições são de suma importância para a preservação dos saberes da comunidade, por isso, nesse ponto, ela foi essencial por ser uma base única e que vem direto da nossa maior fonte de pesquisa: as informações cedidas pelos quilombolas.
ENQUANTO SUA MAGESTADE NÃO MANDAR O CONTRÁRIO”: DIRETÓRIO DOS ÍNDIOS, CARTAS RÉGIAS E A VIOLÊNCIA INDIGENISTA (1757-1809)
Authors: CAROLINE DE OLIVEIRA JESSICA
Published: December 2024

Este artigo tem por objetivo apresentar os princípios que orientaram o Diretório dos Índios e das Cartas Régias enquanto projetos indigenistas entre os anos de 1757 e 1808, bem como, a maneira como estes mecanismos cotejaram formas específicas de violência no tocante à questão indígena. Para o aporte teórico será utilizado Silva (2012), Cancela (2012), Foucault (1986), Fanon (2005), entre outros.
COVID-19, MULHERES RURAIS E ABANDONO
Authors: MACEDO REGO JULYANA , Maria Martins de Paula Helga
Published: December 2024

O presente trabalho tem como objetivo analisar os impactos da pandemia da COVID-19 sobre as mulheres rurais, destacando de que forma esse grupo foi afetado. Para tal, foi adotado o método de revisão bibliográfica, com enfoque em teses, dissertações, obras e artigos que versam sobre o tema proposto. O caminho percorrido para alcançar o objetivo indicado passa por uma breve exposição sobre o Coronavírus, para, na sequência, a partir da análise de dados estatísticos, ser possível evidenciar alguns impactos sociais do período pandêmico. Na terceira seção, o foco é analisar os desdobramentos sobre as mulheres rurais. Ao final, é possível concluir que a crise instalada tem raça, gênero e classe, demonstrando que não se trata de uma crise do Coronavírus, mas de uma crise do sistema neoliberal, e, justamente por isso, os sujeitos são afetados de forma distinta, oportunizando o enriquecimento de alguns, sobre a morte de outros.
FENOMENO DAS DIGITAL INFLUENCERS NOVAS FORMAS DE EXPLORACAO DOS CORPOS FEMININOS NA SEGUNDA DECADA DO SÉCULO XXI
Authors: Nascimento Palha Ana Luiza , Dos Prazeres Silva Adriane
Published: December 2024

Com o advento das novas tecnologias digitais, a sociedade passou por muitas transformações, principalmente no mundo do trabalho. Diante disso, essa pesquisa discute a relação entre trabalho, tecnologia e capitalismo em um recorte de gênero, abordando o trabalho das digitais influencers – mulheres engajadas no Instagram que são capazes de influenciar pessoas através da sua produção de conteúdo. O objetivo desse trabalho é entender como o sistema capitalista, dentro de uma nova roupagem, a das novas tecnologias, utiliza do espaço virtual para perpetuar um sistema baseado na exploração dos corpos femininos. Para entender como todos esses mecanismos se relacionam foram utilizadas fontes digitais: sites e blogs de empresas, publicação do Instagram e vídeos do YouTube. A coleta, organização e avaliação crítica dessas fontes possibilitaram estudar o mundo do trabalho que está se tornando cada vez mais digital. Portanto, um estudo de gênero, em pleno século XXI, na era da informação e comunicação, onde tudo ocorre rapidamente, em um contínuo fluxo de mudanças, devemos notar, é importante não só para a história das mulheres, mas também para a história do tempo presente.
Evaluating Machine Learning Algorithms for Modeling Forest Characteristics in Romania Using Remote Sensing Data
Authors: Keskes Mohamed Islam , Mohamed Aya Hamed , Borz Stelian Alexandru , Niţă Mihai Daniel
Published: December 2024

Forest attributes such as the standing stock, diameter at the breast height, tree height, and basal area, are essential in forest management. Conventional estimation methods, which are still largely used in many parts of the world, are typically resource intensive. Machine learning algorithms working with remotely sensed data trained by ground measurements may provide a promising, more efficient alternative. This study evaluates the performance of three machine learning algo-rithms, namely Random Forest, Classification and Regression Trees, and Gradient Boosting Tree Algorithm in estimating these forest attributes. Ground truth data was sourced by measurements carried out in relevant forests from Romania and by an independent dataset from Brasov County. The predictive ability of the tested algorithms was examined by considering several spatial resolu-tions. The results showed varying degrees of performance. Random Forest was the best performer, with RMSE and R2 values over 0.8 for all attributes. GBTA excelled in predicting the standing stock, achieving R2 values over 0.9. The validation based on the independent dataset has confirmed higher performance for both RF and GBTA. In contrast, CART excelled in predicting the basal area, but struggled with breast height diameter, standing stock, and tree height. A sensitivity analysis that concerned the spatial resolution revealed high degrees of discrepancy. Random Forest and Gradient Boosting Tree Algorithm were more consistent when estimating the standing stock, but they have shown inconsistency for breast height diameter and tree height, while CART showed important variations. These results provide useful insights into the strengths and weaknesses of these algo-rithms, and provide the information required to select the best option when aiming to use similar solutions for estimation.
Aortic Valve Replacement in the Current Era
Authors: Parness Shannon , Womble Jack T. , Hester Tori E. , Tasoudis Panagiotis , Merlo Aurelie E.
Published: December 2024

Aortic valve disease (AVD) is a highly prevalent condition worldwide. Aortic valve replacement (AVR) is the surgical treatment for those with severe disease. Common etiologies of AVD include aortic stenosis (AS), aortic insufficiency (AI), endocarditis, and congenital diseases. Shared decision making plays a large role in the treatment methodology chosen for each patient. Selection of valve type and surgical intervention require strong considerations to age and compatibility with vitamin K antagonists (VKAs) to ensure optimal post-operative outcomes. Due to the development of novel surgical techniques, including transcatheter AVR (TAVR) and placement of sutureless valves, patients who previously had limited access to AVD surgical options can now be considered for AVR. Further research into therapeutic development is imperative to improve patient short- and long-term outcomes as well as widening surgical candidacy for those seeking AVR for management of AVD. Overall, AVR will continue to hold its prominent role in the treatment of AVD.
Control of Multiple Mobile Robots Based on Data Fusion from Proprioceptive and Actuated Exteroceptive Onboard Sensors
Authors: Joon Arpit , Kowalczyk Wojciech , Herman Przemyslaw
Published: December 2024

This paper introduces a team of Automated Guided Vehicles (AGVs) equipped with open-source, perception-enhancing rotating devices. Each device has set of ArUco markers, employed to compute the relative pose of other AGVs. These markers also serve as landmarks, delineating a path for the robots to follow. The authors combined various control methodologies to track the ArUco markers on another rotating device mounted on the AGVs. Behavior trees are implemented to facilitate task-switching or to respond to sudden disturbances, such as environmental obstacles. The Robot Operating System (ROS) is installed on the AGVs to manage high-level controls. The efficacy of the proposed solution is confirmed through a real experiment. This research contributes to the advancement of AGV technology and its potential applications in various fields.
Image Selection Method from Image Sequence to Improve Computational Efficiency of 3D Reconstruction: Application of Fixed Threshold to Remove Redundant Images
Authors: Hanari Toshihide , Nakamura Keita , Imabuchi Takashi , Kawabata Kuniaki
Published: December 2024

This paper describes three-dimensional (3D) reconstruction processes introducing an image selection method to efficiently generate a 3D model from an image sequence. To obtain suitable images for efficient 3D reconstruction, we applied the image selection method to remove redundant images in an image sequence. The proposed method can select suitable images from an image sequence based on optical flow measures and a fixed threshold. As a result, it can reduce the computational cost for 3D reconstruction processes based on the image sequence acquired by a camera. We confirmed that the computational cost of 3D reconstruction processes can be reduced while maintaining the 3D reconstruction accuracy at a constant level.
Toilet Floor Trash Detection System for Unidentified Solid Waste
Authors: Wiyagi Rama Okta , Wada Kazuyoshi
Published: December 2024

The maintenance of public toilets, such as those found in convenience stores, presents challenges in the era of limited human resources. Consequently, the development of an automatic toilet cleaning system is necessary. The detection of trash on the toilet floor is an essential component of the automatic toilet cleaning system. However, this process presents its own set of challenges, including the unpredictability of the types and locations of the trash that may be present. This study proposes a system for detecting solid waste on the toilet floor by applying the structure and feature similarity index method of image. The difference in the structure and features of the reference and actual images can indicate the trash that appears on the toilet floor. This study also proposes a method for determining the threshold value of similarity feature measurement. The experimental results demonstrate that the proposed detection system is able to produce a detection success rate of up to 96.5%. Additionally, the system proves capable of detecting small objects, such as human hair, under specific conditions. This method offers a resource-efficient solution to the challenges faced in maintaining public toilet cleanliness.
ANALYSIS OF FINITE-DIFFERENCE APPROXIMATION OF CODE “FLOW” IN PERFORMING DESIGN CALCULATIONS OF PARAMETERS IN THE PRIMARY AND SECONDARY CIRCUITS OF VVER REACTOR PLANT
Authors: Lys Stepan , Yurasova Oksana , Galyanchuk Igor
Published: December 2024

In code package “FLOW” energy and coolant hydrodynamics equations, neutron kinetics equations and equations of heat conduction in metalwork and fuel rods are solved together. Processes described by these equations are characterized by different time constants and during calculation different degree of time and space discretization is required. The objective of the work was demonstration of stability of numerical schemes used in “FLOW” program and its modules, assessment of error of numerical solution for nodalization. Initial differential equations in partial derivative of the law of conservation of mass, energy and momentum are reduced to the system of usual differential equations on the basis of spatial approximation with the use of integro-interpolation method. Approximation was performed by integrating the initial differential equations in partial derivatives within the limits of each elemental volume of division by spatial coordinate. The usage of integro-interpolation method provides fulfilment of laws of conservation on computational mesh as a whole and the second order of approximation by spatial coordinate. The usage of integro-interpolation method provides fulfilment of laws of conservation on computational mesh as a whole (conservatism of approximation method) and the second order of approximation by spatial coordinate. Effect of limiting error of integration in “FLOW” code on pressure values at the core outlet and mass discharge from the leak is not practically distinguished. Effect of these errors on the values of coolant flow rates at the core inlet and outlet becomes more noticeable. Still, maximum value of these differences doesn’t exceed 7 % for flow rate at the core inlet. More substantial differences (of the order of 10–15 %) are observed in the course of calculated temperature of fuel rod cladding.
AN EXAMPLE OF THE SYNERGY OF THE APPROACHES OF GREEN CHEMISTRY AND GREEN ENERGY
Authors: Petrov Serhii , Danylchenko Dmytro , Kutsenko Serhii , Falalieieva Tetiana , Petrova Yuliia , Minakova Kseniia
Published: December 2024

The current challenges of the modern world related to climate change, environmental pollution, depletion of natural resources, and growing energy needs are examined. New approaches to the production, use and disposal of chemical products and energy that would be sustainable, efficient, safe and competitive are proposed. Green chemistry and green energy are two important areas that are aimed at minimizing or eliminating the use and generation of hazardous substances, the use of renewable energy sources, the improvement of energy efficiency and recovery, as well as the creation of products that would be compatible with the principles of a circular economy and sustainable development The article focuses on the fact that green chemistry and green energy cannot be considered as isolated areas, but must be integrated in a synergistic way to achieve greater efficiency and sustainability. The article consists of three substantive sections: the first section is devoted to green chemistry, the second section - on green energy, and the third section - considers an example of the synergy of green chemistry and green energy approaches in industry. In the work, one of the options for the synergy of the approaches of green chemistry and green energy is investigated, using the example of a simultaneous solution to the problem of clogging the cooling pond of the power plant with algae and the use of these algae as an alternative, economically profitable raw material for the production of biologically active additives and dyes. In this article, on the example of the proposed production, the main principles, directions and examples of synergy of green chemistry and green energy approaches in industry were investigated, as well as an assessment of the advantages, challenges and prospects of such synergy was made. The assessment of advantages and disadvantages proved that a synergistic approach to green chemistry and energy is effective because it allows to achieve greater savings of resources, reduction of emissions and waste, improvement of product quality and increase of competitiveness. This approach also contributes to the creation of innovative solutions that take into account the needs of sustainable development and the circular economy. As a result of the work, it was found that the integration of green chemistry and green energy approaches in industry requires additional scientific research and development to solve a number of problems and challenges. Therefore, the work emphasizes the need to intensify scientific, educational, state and public activities aimed at supporting and developing the synergy of green chemistry and green energy approaches in industry, as one of the key factors of sustainable development of Ukraine.
IMPROVEMENT OF THE STRUCTURE OF THE PARAMETERIC CONTROL SYSTEM OF AN ACTIVE RECTIFIER WITH A FIXED MODULATION FREQUENCY FOR OPERATION IN BIDIRECTIONAL ENERGY FLOW MODE
Authors: Krylov Denis , Kholod Olga
Published: December 2024

The objective need for energy saving and the strengthening of requirements for the quality of consumed electricity forces manufacturers of converting equipment to look for new circuit solutions and to improve the control algorithms of converters. This fully applies to low- and medium-power frequency electric drives. Its base is a structure made on the basis of an autonomous voltage inverter with pulse width modulation, the scheme of which involves the use of a diode uncontrolled rectifier as a source of constant voltage. It has significant disadvantages that can be completely eliminated by an active controlled rectifier - voltage source (AVDN), a parametric control system of which provides a set voltage level in the direct current circuit and a zero value of reactive power with a current form close to a sinusoid on the side of the power network. But it also has certain shortcomings in the mode of changing the direction of the energy flow and needs improvement. Therefore, the improvement of the parametric AVDN control system with a fixed modulation frequency for operation in the mode of bidirectional energy flow between the power network and the load was considered and its simulation was carried out. A solution that ensures stable operation of the converter with an updated control system in all operating modes is proposed. An updated algorithm for the phase correction of the offset angle of the first harmonic of the mains current relative to the voltage of the power source is proposed, and the algorithm for obtaining it has been improved, and the operation of the output voltage regulator of the AVDN circuit has been improved. The simulation results showed that the improved parametric AVDN control system is able to ensure the operation of the power circuit of the converter with a current close to a sinusoid and zero reactive power on the network side in the entire range of changes in the power that consumes or generates the load, maintaining the set value of the output voltage in a stable mode of operation at permissible deviations in transient modes of operation.
CALCULATION OF THREE-PHASE INSTANTANEOUS LINE CURRENTS AT UNBALANCED VOLTAGES
Authors: Demianenko Roman
Published: December 2024

The problem of optimizing the operation of three-phase electrical systems with an isolated neutral used in subways and other critical infrastructure facilities is considered. The various aspects of asymmetric loads that can cause serious disturbances in the operation of the entire power grid, including a decrease in its stability and reliability are analyzed. It is confirmed that traditional methods of analysis often do not take into account real operating conditions, which leads to errors in the design and operation of systems, and the need to develop new, more accurate methods of analysis is emphasised. The approaches to modelling asymmetric modes in networks with an isolated neutral and shows how changes in phase currents affect the stability of the system are considered. It is found that the use of specialized sensors for monitoring currents can significantly increase the system response time to abnormal situations, in particular, during voltage sags in the network. The peculiarity of the proposed calculation method lies in its ability to identify instantaneous changes in line currents very quickly, which play a key role in diagnosing the state of the system and identifying potential failures in its operation. Considering the system of equations of currents in nodes, a significant voltage instability in the subway electrical network during an asymmetric voltage dip was recorded, which indicates the need for further research and problem solving to ensure the reliability and safety of the subway service. The results of the study demonstrate the effectiveness of the proposed method for analyzing and optimizing the operation of three-phase systems with isolated neutral, in particular, by determining and adjusting the critical parameters of the operation of metro traction substations. The methods proposed in this paper will help improve the performance, energy efficiency and reliability of electrical systems, especially in industry and large-scale infrastructure facilities, ensuring a more stable and secure supply of electricity.
THE IMPACT OF CUTTING STRATEGY ON THE GEOMETRY OF THE UNDEFORMED CHIP DURING THE CUTTING-IN STAGE IN THE PROCESSING OF EXTERNAL GEAR USING THE POWER SKIVING METHOD
Authors: Slipchuk Andrii , Dzhura Danylo
Published: December 2024

The kinematics of gear cutting and the modeling algorithm for the cutting-in of the cutting tool into the workpiece is described. This important stage of the cutting process is one of the most dangerous not only in gear turning, but in any machining process, and therefore requires careful study. Analyzing the results of research in this area, and taking into account the rapid development of a relatively new method of gear cutting, we can conclude that there are still a large number of unsolved problems during machining. This is primarily due to the complex kinematics of the process and the associated difficulties in reproducing the cut. In describing the kinematics of gear cutting, we have presented methods for creating a gear cutting simulation model, as well as the coordinate systems required to convert the tool profile coordinate system into the workpiece profile coordinate system. Using the CAD environment, the solid models involved in the process reproduce the cutting process with the best accuracy available. For each of these positions, the exact position of the cutter and the intermediate position of the workpiece at that time were determined. In a specific example, the algorithm was used to generate undeformed cutting profiles for external spur gears with different cutting strategies. In addition, an analytical method was applied to calculate the position of the transition surface and the maximum chip thickness and area were determined and confirmed by simulation for various process parameters, namely depth of cut and number of working transitions. The comparison between the analytically calculated maximum chip thickness and the simulated maximum chip thickness shows a good agreement. The obtained chip thicknesses and cut areas can be used as indicators to control the cutting process and to optimize the process. The nature of the change in chip geometry for different strategies and transitions was determined. With complete information on the geometric values of undeformed chips, it is also possible to determine the qualitative characteristics of the process.
MODIFICATION OF FRICTIONAL SURFACES OF BEARINGS BY ADDITION OF NANOPARTICLE COMPOSITIONS TO LUBRICANTS
Authors: Lyubchenko Olena , Gapochenko Svitlana
Published: December 2024

The results of a study of the effect of additives to lubricating oils on changes in the structure of the friction surface and, as a consequence, the tribological characteristics of the "steel to steel" friction pair are presented. The experiments were conducted using a standard "disk-disk" scheme on a friction machine with double cycles of step loading. The material of the disks was bearing steel ШХ-15 with a hardness of 61-63 HRC. Changes in the surface structure were monitored using a binocular microscope. A detailed study of the friction surfaces was carried out using a scanning electron microscope. The microhardness of the friction surfaces was also measured before and after loading. Quantitative changes in the surface relief were determined using a profilometer. The study of the friction surface, conducted using X-ray fluorescence analysis, revealed changes in the composition of the surface layer, which can be explained by the formation of a surface servovite film, which includes elements from the used additive to lubricant (silicon, magnesium, manganese, aluminum, sulfur). The increase in the microhardness of the friction surface when working with the additive from 4.1 GPa to 6.6 GPa, which has a positive effect on the tribological characteristics, is also explained by the formation of a servovite film, which can significantly improve the friction conditions, as well as reduce damage and wear of surfaces. Using scanning electron microscopy, surface waviness oriented at large angles (close to the normal) to the direction of deformation during friction was revealed. It was assumed that the reason for the formation of such a surface relief is microplastic deformation under the action of bias stresses arising in the surface layers of the friction pair. The structural changes observed during friction with the use of a lubricant additive support the assumption of the formation of a ceramic (servovite) film, which has a significantly greater reserve of plasticity compared to a surface with an oxide film, usually present on the surface during friction with a lubricant without an additive.
PHASE-PULSE FERROELECTRIC PROBE FOR MAGNETIC FIELD MEASUREMENT
Authors: Krykun Vadym , Khomyak Yuri , Korniev Ivan
Published: December 2024

The article deals with a promising direction of development of measuring devices based on the phase-pulse principle. The results of studies of a single-rod ferroelectric probe operating on the basis of the phase-pulse principle of magnetic field measurement are presented. The main purpose of the work was to conduct mathematical studies to optimize the parameters of the ferroelectric probe and determine its performance characteristics under different magnetic fields. The applied mathematical models made it possible to analyze in depth the processes that occur inside the ferroelectric probe during measurements, providing an integrated approach to studying its operation. Particular attention was paid to the influence of external factors, such as temperature fluctuations, the presence of extraneous magnetic fields and other interferences, on the measurement accuracy. This made it possible to identify the conditions under which the accuracy and stability of the ferroelectric probe remain at a high level. Experimental studies have confirmed the effectiveness of the phase-pulse measurement principle, revealing the high sensitivity and speed of the single-rod ferroelectric probe. These characteristics make it promising for use in various scientific and technical fields where accurate magnetic field measurements are required. The article also describes in detail the design features of the ferroelectric probe, the methodology for conducting experimental studies, and the algorithms for processing the data obtained. The obtained results open up new opportunities for the further development of high-precision measuring devices based on the phase-pulse approach, which can be used in a wide range of tasks of modern science and technology. A comparison of the obtained results with other measurement methods was made, which allowed to determine the advantages and disadvantages of the phase-pulse principle. Prospects for further improvement of the ferroprobes design with the aim of increasing their accuracy, reliability and reducing the influence of external factors have been identified.
ENERGY AND OPERATIONAL ANALYSIS OF CONTINUOUS SURVEILLANCE SYSTEMS BASED ON MULTIROTOR UAVS
Authors: Los Andrii , Veligorskyi Oleksandr
Published: December 2024

Drones are used in many applications, including continuous surveillance and monitoring. They can be used in cases, when the deployment time of surveillance system should be as fast as possible, or when a centralized electric grid is not available: accompanying fire extinguishing and liquidation of emergencies, 24/7 surveillance of the border area, monitoring of open-air events. They also can be used as stationary cameras, carrier of means of radio-electronic intelligence, weather conditions intelligence in airport areas, monitoring of crops, etc. The optimal solution for surveillance of large areas, such as critical infrastructure facilities (nuclear power plants, dams), and military facilities (field bases, ammunition warehouses), is the utilization of a group of drones when a single drone will observe his sector. The development of such systems and analysis of conditions for continuous surveillance taking into account the limitations of drone batteries require deep studies of drone energy consumption in various operation modes. The paper proposes a comprehensive investigation of operation modes of continuous surveillance systems, based on drones with electric-supplied propulsion systems, and optimization of its parameters. In the study, a comprehensive analysis of drones’ energy demands was done and conditions for continuous surveillance were found. Based on the parameters of DJI Mavic 2 Enterprise drone and with the use of regression analysis, the optimal flight profile was introduced, for which the maximal achievable distance to the observing point was calculated for the “ideal” case. The case of increasing the drone number for extension of achievable distance to the observation point was investigated and the optimal number of drones for each distance was found. A set of experiments with drone flights was conducted to update and improve the prediction of the drone’s energy consumption during the flight. Finally, the conclusion was set that external parameters, such as wind speed and direction, can significantly decrease the achievable distance to the observing point.
Proyecto Water2REturn: caso práctico del modelo de economía circular en mataderos
Authors: Lorenzo López Antonia María , Zapata Aranda Pilar , Caballero Hernández Alejandro
Published: December 2024

La escasez de agua y la recuperación de recursos son importantes retos globales, y existe una demanda creciente de soluciones circulares que permitan reutilizar el agua y recuperar recursos. Estas soluciones se vuelven imprescindibles cuando se trata de sectores industriales como los mataderos, una industria altamente consumidora de agua y que genera aguas residuales con alta concentración de materia orgánica, una valiosa fuente de nutrientes para la agricultura si se recuperan adecuadamente.
El uso de productos manufacturados a partir de recursos no renovables, como los fertilizantes químicos, se está revisando para encontrar otras opciones más respetuosas con el medio ambiente y evitar posibles problemas de contaminación de las aguas, y su eutrofización.
Water2Return, proyecto financiado por el H2020 de la Comisión Europea, promueve la simbiosis industrial convirtiendo las instalaciones de tratamiento de aguas residuales de los mataderos en biorrefinerías, siguiendo los principios de la Economía Circular, abordando la escasez de agua y la recuperación recursos valiosos, y contribuyendo a la sostenibilidad de los sistemas agroalimentarios. Se llevó a cabo un caso práctico en “Matadero del Sur” en Sevilla (España) tratando 50m3 aguas residuales/día, produciendo agua regenerada, energía y materias primas secundarias para la formulación de productos agrícolas de alto valor añadido.