bluuebunny/crossref_metadata_2025 huggingface dataset:
Couette flow of micropolar fluid in a channel filled with anisotropic porous medium
Authors: Verma Vineet Kumar , Ansari Abdul Faiz
Published: October 2024

This paper presents a mathematical model for the flow of micropolar fluid in a horizontal channel filled with an anisotropic porous medium, bounded by two parallel plates—where the upper plate is stationary, and the lower plate moves at a constant velocity. The flow, driven by both a constant pressure gradient and the movement of the lower plate, is governed by the Darcy-Brinkman equation. Using no-slip and no-spin boundary conditions, we analytically derive expressions for the velocity, microrotational velocity, and stress distributions. The study provides a graphical analysis of the flow behavior influenced by key parameters such as the Darcy number, porous medium anisotropy, anisotropy angle, and the micropolar fluid’s material parameters. Furthermore, the effects of the material parameters and Darcy number on shear stress and couple stress are thoroughly investigated. The findings have applications in modeling fluid flow in striated or fractured rock formations.
Changes in ruminal fermentation and rumen bacteria population in feedlot cattle during a high lipid diet adaptation
Authors: Vesga Daniela A. , Granja-Salcedo Yury T. , Costa Rayanne V. , Gomes Kenia L. , Alves Carvalho , Narvaez Hector J. , Berchielli Telma T.
Published: October 2024

This study aimed to investigate changes in feed intake and ruminal environmental parameters during a high-lipid diet transition in cattle. Eight Nellore steers were fed a control diet composed of 30% hay and 70% concentrate for 21 days, followed by the inclusion of 60 g/kg dry matter of soybean oil for 21 days. The DM intake expressed as a percentage of BW 21 days after lipid inclusion was lower (1.75% BW) than that observed during the control diet feeding (1.81% BW) (P<0.01). Steers fed the control diet had a lower pH than the ruminal pH recorded on days 7, 14, and 21 after lipid inclusion (P=0.034). Lower total short-chain fatty acid production in the rumen and lower microbial nitrogen synthesis were observed on day 7 after lipid inclusion compared to values found when steers were fed the control diet and on days 14 and 21 after lipid inclusion (P=0.041). Lipid inclusion in the diet decreased the population of protozoa on days 7, 14, and 21 (P<0.001). The abundances of R. albus and F. succinogenes were higher when steers were fed the control diet than the abundance observed on days 7, 14, and 21 after lipid inclusion in the diet (P<0.05). The first seven days of lipid diet inclusion are considered the most critical for ruminal adaptation, involving reductions in fibrolytic bacteria and changes in fermentation parameters. After 14 days the rumen showed signs of recovery and adaptation.
Development of selected performance, dressing and meat quality traits of Pekin ducks in relation to genotype and phytogenic feed additives
Authors: Lewko Lidia , Gornowicz Ewa , Kryza Artur , Adamski Marek
Published: October 2024

The aim of this study was to determine the effect of the genetic origin of ducks and the use of phytogenic additives in their feeding on performance indices, slaughter value and dressing percentage, as well as meat quality. The experimental material consisted of three genetic groups of Pekin ducks: Polish Pekin P-33 (P), Dworka D-11 (D) and Star 53 H.Y. (S). A 7-week experimental rearing of 216 commercial hybrids (3 × 72 animals) was carried out. Within each genetic line, three feeding groups were established, differing in the use of plant-based additives in the feed mixture (5% herb mixture or 5% black cumin seed). To assess slaughter value and meat quality of the ducks, 18 birds from each group were selected, including 9 males and 9 females. It was shown that the basic performance and slaughter value traits of Pekin ducks depend (p≤0.05) on their genetic origin. The most favourable (p≤0.05) rearing efficiency and slaughter value (body, carcass and meat weight) were found for commercial Star 53 HY ducks. Their breast muscles were characterized by higher (p≤0.05) cooking loss and lower (p≤0.05) collagen content. The genetic origin of the ducks was shown to influence (p≤0.05) economic efficiency of rearing, dressing percentage and chemical indicators of meat (except for water content in breast muscles) and some physical characteristics (pH24, cooking loss, colour lightness of leg muscles and electrical conductivity in breast muscles). Supplementation of the standard diet of ducks with phytogenic additives (mixture of herbs, black cumin seeds) at a level of 5% had (p≤0.05) a negative effect on body, carcass and meat weight, and a positive effect on the physical characteristics of meat related to water loss (pH24 and cooking loss).
Effect of the competitive exclusion culture on the growth, blood parameters, leg health, and innate immunity of broiler chickens
Authors: Żbikowski Artur , Michalczuk Monika , Pawłowski Karol , Adamczyk Krzysztof , Szafraniec Gustaw , Witkowska-Piłaszewicz Olga , Bień Damian , Damaziak Krzysztof , Łukasiewicz-Mierzejewska Monika , Dolka Beata , Kaukonen Eija , Szeleszczuk Piotr
Published: October 2024

The primary aim of poultry production is to obtain a high yield and quality end product. To reduce the risk of disease, many direct-fed microbial products have been developed. That appears to be an excellent tool for disease prevention.

We evaluated the influence of the commercial, competitive exclusion (CE) product, Broilact®, on the growth rate, hematology, serum biochemistry, and innate immunity in male ROSS-308 chickens, randomly divided into two groups (Broilact® treatment and control) raised for 42 days.

The birds’ body weight was determined at 1, 7, 14, 28, 35, and 42 days, and the blood samples were collected at days 22 and 42 of life. We observed lower mortality, better gait score, and higher final body weight in the Broilact® group. At day 22, birds from the treated group presented higher white blood cells counts (WBC) and T cytotoxic lymphocyte (CD8+) counts, higher total protein (TP) (fraction globulin and albumin), and lower triglyceride (TAG) and Ca2+ plasma concentrations. No differences were found in acute phase proteins (APPs). At day 42, only the K+ and Na+ concentrations were higher, while the IL-10 was lower in treated birds’ blood serum.

Our results indicate that treatment with one dose of the Broilact® product at day one of life has a beneficial influence, which improves the chickens’ performance, leg health and some serum enzymes activity, maintains electrolyte homeostasis, and influences leukocyte count with the rise of T CD8+ subpopulations.
Emotional fuctioning of people who experienced COVID-19 infection - the moderating role of gender
Authors: Gradowska Aleksandra , Szyls Patryk , Zadka Katarzyna , Ziora-Jakutowicz Karolina , Ławiński Michał
Published: October 2024

The COVID-19 pandemic had a significant impact on people’s psychological functioning, altering emotional lives by increasing anxiety and lowering mood. The purpose of the present study was to analyze the impact of COVID-19 infection on anxiety and mood, and to examine the role of gender and the significance of the number of infections. The study was based on a questionnaire and involved 210 participants (n = 101 who contracted COVID-19 and n = 109 who never experienced the disease). The Anxiety and Depression Scale (HADS), a tool with good psychometric properties, was used for assessment.

Gender differences were observed in levels of anxiety and depression. Men reported higher levels of anxiety and depression compared to women. Interestingly, those who had not experienced COVID-19 reported higher levels of depression. The study indicated a moderating role of gender in the relationship between anxiety, depression, and the number of infections. Experiencing an infection may reduce tension and possibly increase feelings of better coping and greater self-confidence, which is particularly significant for men, given the persistence of stereotypical attitudes towards male and female roles in society.

The individual experience of COVID-19 infection, coupled with the unpredictability of the body’s response, may foster a sense of uncertainty, exacerbating negative emotions. However, participants who had contracted the disease learned to cope with it and developed some immunity, which might explain the observed differences. This conclusion is important in the context of potential subsequent waves of the epidemic.
Unveiling the Subterranean Heritage: A Case Study of the Underground City of Kukës, Albania
Authors: Dobjani Etleva , Kristo Saimir
Published: October 2024

This paper investigates the viability of conserving and repurposing Kukës’ underground city, which was built as a system of civil defence tunnels during the communist era in Albania. Beneath contemporary Kukës, the underground complex, which houses administrative offices and hospitals, is an important but underutilized historical and architectural asset. This study assesses the architectural elements, historical value, and present state of the tunnels using an extensive methodology that includes expert interviews, public consultations, on-site inspections, and archival research. Results highlight the site’s dual significance as a historical landmark and a possible center for innovation and tourism.

The research offers strategic proposals for reviving the tunnels to strengthen the local economy, maintain cultural identity, and increase tourist attraction, drawing on foreign case studies. By promoting the inclusion of Kukës’ underground city in larger regional development projects and considering both community goals and pragmatic concerns, the article adds to the current conversations in urban planning and cultural preservation.

Sustaining and repurposing Kukës’ underground city has various benefits, including enhanced cultural tourism and economic resurgence that encourage sustainable growth, the paper points out. Still, challenges like deteriorating infrastructure, security concerns, and accessibility issues must be overcome. Urban planners and politicians can apply the research’s practical implications by using it to develop a model for cultural preservation that aligns with modern social and economic goals.

A sense of shared identity and legacy among the local community’s members is fostered by the initiative, which has significant social implications as well. The study has some drawbacks, including the need for significant funding and the potential for opposition from groups who do not recognize the advantages of these kinds of initiatives. To summarise, this research highlights the potential of adaptive reuse to bolster the sustainability and resilience of urban ecosystems by offering useful guidance and strategies that may be used to comparable initiatives worldwide.
Access to justice in Albania and EU policies
Authors: Kasaj Arjana Llano
Published: October 2024

Access to justice is a fundamental element of the rule of law and a cornerstone of justice. Access to justice is the constitutional guarantee that enables individuals to have their violated rights protected. Governments must guarantee the right of every individual to address the court or other bodies of public administration. The right of access to the court in order to oppose an act of the public administration bodies is an autonomous fundamental right and an element of due process. This principle closely relates to another principle guaranteeing justice and democracy in society, which is the principle of the rule of law. Albania has not yet adopted a law that provides for the vital minimum; calculation of financial insufficiency threshold by considering only the income of a person rather than the necessary and obligatory living costs that really need free legal aid. National and international acts provide for Access to Justice, and the onus remains on the government to provide this right to its citizens. In 2022, the number of courts in Albania dropped significantly with the new judicial map, which significantly reduced the access of citizens. Why reduce the number of courts? This led to the increase in the stock of court files and the failure of judges to try cases within the legal deadlines. Albania should reflect without further delay and increase the number of courts, taking an example from other developed European countries, so that citizens may easily go to the courts
Climate Change Perceptions: A Study With Portuguese University Social Education Students
Authors: Ramos Ricardo , Vaz Paula , Rodrigues Maria José , Rodrigues Isilda
Published: October 2024

Climate change (CC) is one of the most urgent problems to solve in this century, the effects of which cover a wide range of disciplines that go beyond the environmental component, becoming a social and economic problem as well. Social educators are professionals who must ensure that the quality of life in socially vulnerable societies is improved. In order to mitigate the problem of climate change, it is necessary for all professionals in the most varied areas to have climate literacy, so that they can adopt behaviors that comply with the objectives of sustainable development. Recognizing the importance of the social educator in the context of contemporary societies, we intended to find out the university students’ perceptions on the social education course. With this in mind, we set out to carry out this study, which was based on the application of a questionnaire using a Likert scale. The respondents were 161 social education students at a higher education institution in Portugal. In order to carry out the inferential analysis, we took care to meet the necessary criteria for carrying out parametric tests. The results showed that a majority (72.6 %) of students were concerned about climate change. They (54.7 %) also stated that they would like their course to deal more with climate change, as 74 % acknowledged that they did not have the skills to deal with climate change as a future professional. The results also showed that the students were incapable of correctly listing a consequence of climate change. The data collected and analyzed in this study allowed us to conclude that Environmental Education played a fundamental role in the academic training of social educators, suggesting the need for its reinforcement and inclusion in their training plans. We also found that greater efforts were needed to improve students’ climate literacy.
High-Impact Educational Practices (HIEPs) in Educational Media: Towards a Proposed Vision for the Sustainability of Egyptian Specifiic Education
Authors: Zaghloul Hisham Saad
Published: October 2024

Sustainable education and teaching excellence in Egypt remain significant challenges due to the persistent reliance on conventional and theoretical curricula, highlighting the dire importance of innovative practices for educators. Specific education should be encouraged at higher education levels, particularly in educational media. However, its adoption remains challenging due to unclear objectives and ineffective practices. High-impact educational practices (HIEPs) would provide an incentive for improved learning among the students. Thus, the current study focuses on the high impact of educational practices in exploring the importance of HIEPs in higher education in general and the educational media for specific education at Mansoura University in particular. Fifty faculty members in the field of educational media from specific educational colleges across various Egyptian universities participated in the survey. The study identifies the government’s focus on quantity over quality, poor teaching standards, and social inequalities as critical factors necessitating the implementation of HIEPs. In turn, all these practices add to deriving improved engagement, delivery of transferable and elementary skills, or synthesizing learning from related courses. The study concluded that it is important for the Department of Educational Media and its sub-specialties, including Drama, Educational Theatre, Radio, Television, and Educational Journalism, to integrate HIEPs and foster innovative practices in theatre education, in light of the 21st-century skills, skills gaps, ICT implementation, and support of teachers to increase the sustainability, particularly in educational media.
Opinions of Pre-Service Preschool Teachers About Purposefulness: Sustainability Aspect
Authors: Jurgena Inese , Cēdere Dagnija , Keviša Ingrīda
Published: October 2024

The contradictions of human development nowadays are related to the educational environment, which is characterized by changes induced by globalization and modern technologies; therefore, the activation of the potential of personality is becoming increasingly important, which is impossible without the training of purposeful and motivated teachers at the institutions of higher education. The aim of the article is to analyze the opinions of students, pre-service preschool teachers, about teacher purposefulness in the context of sustainability. The research methodology includes the theoretical method – the analysis of theoretical literature and the empirical method – a survey of 271 pre-service teachers, i.e., 1st-year part-time students at the University of Latvia. The results of the study show that future preschool teachers’ understanding of purposefulness is related to their life experiences and is formed in relation to the development of personal goals.
A Teachers’ Coaching Approach to Sustainable Professional Development
Authors: Manal Raoui , Mohamed Droui , Fatima-Zahra Guerss
Published: October 2024

The value of coaching teachers by professional coaches in their school context is recognized to provide them with sustainable professional development (SPD). However, little is known about the coaching process promoting SPD and the variables that can explain its quality. Three objectives were pursued: 1) to describe the quality of the coaching process; 2) to determine the characteristics of the coach, and 3) to identify the characteristics of the school context that can explain quality to promote SPD. An Embedded Multiple-Case Study Design was conducted at two different schools. Results describe that the quality of the coaching process was clear in its orientation to precise goals, its complexity, and its dynamism. The coaches’ characteristics that can explain the quality of the coaching process to promote SPD are their perceptions of the context and their conceptions. The most important characteristic of the context that can reveal the quality of coaching enacted is the leadership of the school principal and the teachers’ culture of collaboration.
Education for Sustainability Through Field Activities and Game-Based Tasks
Authors: Saraiva Elisa , Faria Fábio , Ferreira Célia , Azevedo Maria Manuel
Published: October 2024

There is a consensus that the content of education for sustainability should be integrated into the curriculum, engaging students in activities that promote awareness and practice of sustainability. To achieve this goal, it is essential to adopt a student-centered approach that involves creative, stimulating, and challenging activities. This research reports a case study in which 8th grade students had the opportunity to develop these types of activities. Field activities were conducted on a local river combined with a game-based task focused on the role of benthic macroinvertebrates in ecosystems. These activities enabled collaborative learning and the social construction of knowledge, which are pivotal for more sustainable education. It should be noted that students learned how to collect, observe, describe, organize, and classify species to make inferences about water quality. The main issue we intended to address was how to improve and integrate scientific activities into the students’ curriculum to foster a more sustainable education. The specific research questions were put forward: a) Do the implemented activities instigate collaboration for a more sustainable education? b) Do the implemented activities increase scientific curiosity and develop critical thinking and attitudes? c) Do the implemented activities increase students’ knowledge concerning aquatic resources, such as benthic invertebrates? The results confirmed the important role of student-centred activities, in this particular case fieldwork and game-based tasks, in the development of knowledge and scientific thinking skills, which could be scaffolded through feedback, rewards and flow states. This study provides a more holistic perception of local river ecosystems, their role in improving environmental attitudes, and promoting a more sustainable science education.
Global Competence and Sustainable Development in Teacher Training: Preparing for a Changing World
Authors: Bilbokaitė Renata , Bilbokaitė-Skiauterienė Ieva , Fjodorova Ilona , Kravale-Pauliņa Mārīte , Oļehnoviča Eridiana , Szplit Agnieszka , Zbróg Zuzanna
Published: October 2024

This cross-cultural study examines the inclusion of global competences (GCs) in the curriculum of teacher education programs across three Baltic Sea countries: Latvia, Lithuania, and Poland. Using van den Akker’s (2003) substantive approach to curriculum analysis, the researchers analyzed official documents and course descriptions of Daugavpils University (Latvia), Vilnius University Šiauliai Academy (Lithuania), and Jan Kochanowski University of Kielce (Poland). Employing Rapley’s (2007) document analysis method, the study focused on both explicit content and implicit gaps to assess how well GCs are integrated into teacher training programs for primary and preschool education. The research involved a detailed examination of 262 syllabi, comprising 63 from Latvia, 61 from Lithuania, and 138 from Poland. The researchers used a template based on the PISA 2018 Global Competence Framework to identify which competences and sub-competences were included in the syllabi. The study aimed to answer the question: How are all the dimensions of global competences included in the syllabi of courses taught at the primary and preschool education levels in three Baltic Sea countries? The findings reveal that the Lithuanian curriculum includes the most GC-focused courses (92 courses, 276 ECTS), followed by Poland (44 courses, 99 ECTS), and Latvia (30 courses, 161 ECTS). The analysis was conducted in four steps: comparing the total number of courses and ECTS credits, ranking the development level of each GC dimension, characterizing the development of each dimension, and analyzing the general approach towards incorporating GCs into the curricula. The results indicate a significant variation in how GCs are integrated across the three countries, with Lithuania demonstrating the most comprehensive incorporation. The study highlights the need for a more sustainable, systematic and consistent inclusion of global competences in teacher education to better prepare educators for a globalized world.
On I -Statistically Cauchy Sequences & the Class of I -Statistically Concurrent Sequences
Authors: Rakshit Debjani , Bal Prasenjit , Debnath Shyamal
Published: October 2024

In this article, we present the ideas of I-statistically Cauchy criteria and I

∗
-statistically Cauchy criteria, which are the generalizations of I-Cauchy and I

∗
-Cauchy criterion, respectively. To grasp the differences, we compare this I-statistically Cauchy criterion with a few other Cauchy criteria. Also, we investigate a few characteristics of I

∗
-statistically Cauchy sequences and I-statistically Cauchy sequences and demonstrate their equivalence under the condition that the ideal I satisfies the property (AP). Furthermore, a relation is defined on the set SX
of all sequences in a metric space, which comes out to be an equivalence relation. Finally, we show that if two sequences belong to the same equivalence class, then either both of them are I-statistically Cauchy or none of them are.
On O’malley Lower Porouscontinuous Functions
Authors: Bilski Jakub , Kamińska Anna , Kowalczyk Stanisław , Turowska Małgorzata
Published: October 2024

In 2014, J. Borsík and J. Holos defined porouscontinuous functions. Using the notion of density in the sense of O’Malley, new definitions of porouscontinuity were introduced in 2021, namely ℳ𝒪
r
and 𝒮𝒪
r
-continuity. These kinds of porouscontinuity used upper porosity. We consider lower porous-continuity in the sense of O’Malley, where lower porosity is used instead of standard (upper) porosity.
Neutrosophic Fuzzy Tribonacci ℐ-Lacunary Statistical Convergent Sequence Spaces
Authors: Khan Vakeel A. , Kişi Ömer , Choudhury Chiranjib
Published: October 2024

The aim of this paper is to introduce and investigate some neutrosophic fuzzy tribonacci ℐ-lacunary statistical convergent sequence spaces by utilizing the domain of regular tribonacci matrix A = (ajk
). Morever, we also put forward various algebraic and topological features of these convergent sequence spaces and establish several interesting inclusion relations.
A Fixed Point Approach to the Stability of a Quadratic Functional Equation in Modular Spaces Without Δ2-Conditions
Authors: Saha Parbati , Kayal Nabin C. , Choudhury Binayak S. , Dutta Santu , Mondal Sankar Prasad
Published: October 2024

In this paper, we investigate the Hyers-Ulam-Rassias stability property of a quadratic functional equation. The even and odd cases for the corresponding function are treated separately before combining them into a single stability result. The study is undertaken in a relatively new structure of modular spaces. The theorems are deduced without using the familiar Δ2-property of that space. This complicated the proofs. In the proofs, a fixed point methodology is used for which a modular space version of Banach contraction mapping principle is utilized. Several corollaries and an illustrative example are provided.
RETRACTED: Sharp and Weighted Boundedness for Multilinear Integral Operators
Authors: Xia Xiuyun , Chen Huatao , Tian Hao , Wang Ye , Shi Yadan
Published: October 2024

In this paper, the weighted boundedness for some multilinear operators related to the Littlewood-Paley operator and Marcinkiewicz operator on the generalized Morrey spaces are obtained by using the sharp estimates of the multilinear operators.
Sustainability and Strategic Positioning in Hydroponic Production
Authors: Vieira Vera Lúcia Fernandes , Norato Hélida Mara Gomes , Duarte Anderson Ribeiro
Published: October 2024

Objective: This study analyzes the strategic positioning of a family farming company, exploring intersections in support of the certification process for the organic production of leafy vegetables.
 
Theoretical Framework: We adopt a qualitative approach to achieve the objective through a case study on a farm in Minas Gerais/Brazil. We present details on hydroponics, the sustainability tripod, and strategic planning.
 
Method: We presented an analysis of strategic planning. We applied case studies and bibliographic research. We employed a qualitative approach based on information obtained through interviews and in-loco observations.
 
Results and Discussion: The results present the analysis of the SWOT matrix that compares the internal conditions of the organization with market conditions. The results highlighted the potential of the company under investigation. The offensive capacity demonstrates excellent conditions for taking advantage of opportunities. The defensive capacity reported the vulnerability to repel threats.
 
Research Implications: This case study highlights the potential of analyzing strategic positioning. By applying the SWOT matrix and calculating strategic positioning, a significant positive value that attests to the offensive capacity in relation to the external environment was observed.
 
Originality/Value: This study discusses the applicability of strategic positioning analysis for hydroponic companie sthrough sustainability actions. The interest in this product is widely known and highlights the relevance of studies to foster the evolution of strategic management in this segment.
Homenagem a Juliano Moreira: sinônimo de representatividade e vanguardismo
Authors: Sousa Eduardo Morales , Fischer Audrey Ribeiro
Published: October 2024

Por meio de homenagens, podemos resgatar histórias de personalidades ilustres e ressaltar marcos do passado, seu impacto no presente e torná-los como inspiração para o futuro. Neste sentido, Juliano Moreira se destaca como um dos expoentes que jamais deve cair no ostracismo: responsável por alicerces da psiquiatria brasileira, seu engajamento e pioneirismo foram feitos em uma época ainda mais hostil do que os tempos atuais. Sendo a medicina um curso historicamente elitizado, pessoas de origem socioeconômica humilde e até mesmo negros tiveram seu acesso dificultado, não tendo as mesmas oportunidades que os demais. Indo além, Juliano não só traz uma necessária representatividade, mas sua bagagem e história refutando o racismo científico que, à época, pregava uma “inferioridade biológica” a raças humanas. Passados mais de 90 anos de sua morte, observamos diversos avanços em nossa sociedade e na própria psiquiatria, sustentados em grande parte na luta de agentes como Juliano – pioneiro na reforma psiquiátrica brasileira e no combate à discriminação, sendo esta responsável, por exemplo pelo tratamento diferenciado empregado à época a pessoas abastadas quando comparadas a pacientes sem posses.
Support Vector Machine Framework for Detecting Ambiguous Contours of Space Debris Cloud
Authors: Morimoto Daisuke , Takahashi Hikaru , Sugiyama Yoshihiro , Otsuka Keisuke , Ohtani Kiyonobu , Hasegawa Sunao , Makihara Kanjuro
Published: October 2024

Operational spacecraft are prepared for collisions with space debris by installing protective walls (bumpers). A group of vaporized and liquefied microparticles generated by debris collisions is called a debris cloud. To evaluate the protective performance of bumpers, it is important to measure the spread velocity and angle of the debris cloud. However, debris cloud images exhibit ambiguous contours of debris clouds. Consequently, measurement errors in the spread velocity and spread angles occur because of the observer’s subjectivity. Commonly used derivative-based methods can detect steep contours; however, they cannot detect ambiguous contours such as those of debris clouds. In this study, a method for uniquely detecting the ambiguous contours of a debris cloud based on supervised machine learning and a continuous wavelet transform (CWT) is proposed. Feature points that indicate candidate points of the debris cloud contour are extracted using a method based on CWT. Four types of specific features for debris cloud contours were assigned to the feature points. Supervised machine learning using a support vector machine can detect the debris cloud contours. The proposed method enables the evaluation of the ambiguous contours of a debris cloud and the protection performance of a bumper without observer subjectivity.
Neural-Rendezvous: Provably Robust Guidance and Control to Encounter Interstellar Objects
Authors: Tsukamoto Hiroyasu , Chung Soon-Jo , Nakka Yashwanth Kumar , Donitz Benjamin , Mages Declan , Ingham Michel
Published: October 2024

Interstellar objects (ISOs) are likely representatives of primitive materials invaluable in understanding exoplanetary star systems. Due to their poorly constrained orbits with generally high inclinations and relative velocities, however, exploring ISOs with conventional human-in-the-loop approaches is significantly challenging. This paper presents Neural-Rendezvous—a deep-learning-based guidance and control framework for encountering fast-moving objects, including ISOs, robustly, accurately, and autonomously in real time. It uses pointwise minimum norm tracking control on top of a guidance policy modeled by a spectrally normalized deep neural network, where its hyperparameters are tuned with a loss function directly penalizing the model predictive control state trajectory tracking error. We show that Neural-Rendezvous provides a high probability exponential bound on the expected spacecraft delivery error, the proof of which leverages stochastic incremental stability analysis. In particular, it is used to construct a non-negative function with a supermartingale property, explicitly accounting for the ISO state uncertainty and the local nature of nonlinear state estimation guarantees. In numerical simulations, Neural-Rendezvous is demonstrated to satisfy the expected error bound for 100 ISO candidates. This performance is also empirically validated using our spacecraft simulator and in high-conflict and distributed unmanned aerial vehicle swarm reconfiguration with up to 20 unmanned aerial vehicles.
Low-Thrust Fuel-Optimal Guidance with Automatic Control Sequence Detection and Separation
Authors: Evans Adam , Armellin Roberto , Pirovano Laura
Published: October 2024

This paper develops a novel fuel-optimal guidance scheme using differential algebraic techniques that is capable of handling changes in the optimal thrust sequence, in addition to a large domain of uncertainty. Taylor polynomials of the solution flow exhibit large approximation errors when the control sequence changes within the domain of operation. This property is leveraged through automatic domain splitting, a technique that tracks the approximation error and splits the domain into smaller subdomains when high errors are observed. After multiple splits, the domain is autonomously separated along the boundaries between different optimal control sequences. Crucially, each resulting subdomain encompasses only a single control sequence, ensuring that any guidance updates obtained from the final polynomial map provide the corresponding optimal control sequence. To ensure high accuracy of the guidance updates, this work also develops an efficient and iterative-less differential-algebra-based refinement algorithm, which is applied to the outputs of the polynomial map. The overall guidance scheme provides highly accurate guidance updates in response to large trajectory deviations, including new optimal control sequences, as demonstrated in an Earth–Psyche transfer.
Accuracy and Computational Cost Comparison of Numerical Flight Dynamics Reduced-Order Models
Authors: Isnard Baptiste , Tanguy Geoffrey , Farcy Dominique , Dugeai Alain , Garnier Eric , Foucaut Jean-Marc
Published: October 2024

This paper compares several approaches to model the unsteady and nonlinear longitudinal aerodynamics of a generic unmanned combat air vehicle configuration based on computational fluid dynamics (CFD). Three different reduced-order models (ROMs) are implemented through unsteady simulations to predict the evolution of forces and moments during prescribed trajectories carried out at [Formula: see text]. The first model investigates a linear quasi-steady model based on a first-order Taylor series expansion of the aerodynamic coefficients. The second one picks up the mathematical formulation of the first model but adds a dynamic coefficient in order to take into account the unsteady effect of rotation rate variations. Finally, the third model is built on indicial functions computed from positive step changes in the angle of attack or pitch rate. The unknown parameters of the first two models and the unknown indicial functions of the third one are obtained, respectively, from the study of forced oscillations and step motions. These prescribed trajectories are performed using unsteady Reynolds-averaged Navier–Stokes simulations coupled with a grid displacement tool. Two different methods are tested and compared to carry out the CFD mesh motions: an overset method and a full moving grid (FMG) method. The indicial functions obtained using the FMG method give results equivalent to those found in the literature in half the time of the overset method. To reduce the computational costs to set up the ROMs, the FMG method is preferred to the overset method. ROMs are then applied, and their predictions are compared with CFD simulations for prescribed trajectories with different angular rates and angles of attack. A study of instantaneous and overall accuracy associated with the implementation cost of the ROMs has allowed to show their strengths and their weaknesses. Similar results are observed at low angles of attack for the ROMs studied, while a major modeling advantage of the indicial method has been identified for higher angles of attack in the nonlinear domain.
Interferometric Rayleigh Scattering for Flow Temperature and Velocity Analysis
Authors: Kurek Igor , Lecomte Pierre , Castelain Thomas , Jondeau Emmanuel , Bailly Christophe
Published: October 2024

A new processing method is developed to analyze images from a Fabry–Pérot interferometer in order to extract point measurements of temperature and velocity within a gas flow, using Rayleigh scattering. Two types of interferograms are generated from a Fabry–Pérot model combined with a simulated light source. The first type is obtained from a diffuse coherent light source, namely, a laser beam on a diffuser. The interferometer characteristics, defined by only two independent parameters, are retrieved within 0.1% accuracy. The knowledge of these parameters is mandatory to analyze interferograms from Rayleigh scattered light. The second type corresponds to Rayleigh scattered light from a small volume under flow conditions, lighted with a focused laser beam and captured with long exposure time. Several flow parameters are chosen to generate these interferograms. The relative errors on the temperature and velocity estimates are found to be weak. Noise is also added to assess the robustness of the processing method. The error induced by the estimates of the instrument function is found to be of second order compared to the error induced by the image analysis.
Parameter-Free Data Reduction for Short-Time Hypersonic Heat Flux Measurements
Authors: Frankel J. I. , Shu F. , Gross A.
Published: October 2024

High-speed flows associated with hypersonics require significant, diverse, and successful ground-test campaigns before engaging in a flight test program. The present investigation focuses on demonstrating a new data reduction pathway for estimating the source heat flux using an elegant, though fragile, thin-film temperature gauge. The rapid response time of such sensors makes them well-suited for shock tunnel experiments. In such experiments, contaminated flow, composed of diaphragm debris, can often damage the sensing element. For the moment, the existence of an ideal coating (or even a hardened sensing element) is presumed that preserves the sensor’s survivability and accuracy over several test runs. A dynamic, physics-based data reduction methodology is proposed that accounts for the protective coating and that is applicable to millisecond testing times. This paper addresses three critical issues for acquiring the best estimate of the source heat flux. These issues include a) the formation of a baseline data reduction view that accounts for thin coatings; b) the development of a dynamic calibration method that removes the need for specifying thermophysical or geometrical properties; and c) the introduction of a time-scaling that allows for calibration to be performed in alternative and convenient time frames. This last point demonstrates the concept of the dimensionless time map and its novel consequences. The procedure is demonstrated on a reduced formulation, illustrating the merit of the concepts.
Elaboração e validação de um caso ficcional sobre a influência do estilo de vida na acne
Authors: Guimarães Emmanuel Sousa , Cadena Marilia Ribeiro Sales
Published: October 2024

Objetivo: Elaborar e validar um caso ficcional a fim de fornecer aos estudantes e professores do ensino médio um recurso com informações precisas para compreensão da acne e a relação da doença com a alimentação e exercício físico (estilo de vida). Métodos: Trata-se de um estudo metodológico descritivo para validação de um caso ficcional. O caso foi elaborado após revisão bibliográfica considerando os preceitos para um bom caso e os critérios de validação de produtos de ensino. A versão final do caso foi avaliada por 8 docentes (juízes) a partir de questionário de validação. As assertivas do questionário se apresentavam em escala Likert para cálculo do índice de validade de conteúdo (IVC). Resultados: O caso foi validado pelos juízes com IVC global de 0,95. O IVC foi o mesmo para os itens que se referem aos critérios para um bom caso e para os itens que se referem à validação como produto de ensino. Conclusão: Ressaltamos que as discordâncias apresentadas pelos juízes são vistas como sugestões de melhoria e formas de adaptar o caso para as necessidades do profissional que utilizará esta ferramenta.
Gender Dysphoria in Turner Syndrome
Authors: Pinheiro Tayana Leandro , Lima Junior David Nunes De , Fontenele Eveline Gadelha Pereira , Campos Eugênio de Moura , Grangeiro Carlos Henrique Paiva , Macêdo Danielle , Furtado Cristiana Libardi Miranda , Sales Sarah Leyenne Alves , Sanders Lia Lira Olivier
Published: October 2024

Objectives: To report a case of a patient with Turner Syndrome (TS) experiencing gender dysphoria (GD), which refers to the psychological distress (lasting at least six months) that may result from an incongruence between the given and the experienced gender. Case Details: At sixteen, the patient realized she wanted to belong to the opposite gender, wishing to eliminate female secondary sexual characteristics. The patient developed a fleeting consideration of suicide and engaged in non-suicidal self-injury. Her mood symptoms worsened at nineteen, and she became more socially isolated as her academic performance declined. At 21, she did not present GD and did not want to transition gender anymore. Final Considerations: To the best of our knowledge, this is the first report of GD in a patient with the syndrome. It aligns with the understanding that gender identity is not only a social process but also a unique, individual construction. This case report highlights the importance of caution in transitional procedures since patients may need time to build their gender identity.
Robust Controller Design Ensuring the Desired Aperiodic Stability Degree of a Control System with Affine Uncertainty
Authors: S.A. Gayvoronskiy , I.V. Khozhaev , A.V. Sobol
Published: October 2024

This paper considers a system whose characteristic polynomial coefficients are linear combinations of the interval parameters of a plant forming a parametric polytope. A linear robust controller is parametrically designed to place a dominant pole of the system within the desired interval of the negative real semi-axis and ensure an aperiodic transient in the system. The parametric design procedure involves a low-order controller with dependent and free parameters: the former serve to place the dominant pole within the desired interval on the complex plane whereas the latter to shift the other poles to some localization regions beyond a given bound (to the left of the dominant pole to satisfy the pole dominance principle). To evaluate the dependent parameters of the controller, the originals of the interval bounds of the dominant pole are determined for the plant’s parametric polytope based on a corresponding theorem (see below). The free parameters of the controller are chosen using the robust vertex or edge D-partition method, depending on the boundary edge branches of the localization regions of the free poles. A numerical example of the parametric design procedure is provided: a PID controller is built to ensure an acceptable aperiodic transient time in a load-lifting mechanism with interval values of cable length and load weight.
Design of Self–Checking Digital Devices with Boolean Signals Correction Using Weight-Based Bose–Lin Codes
Authors: D.V. Efanov , Y.I. Yelina
Published: October 2024

This paper proposes a method for designing self-checking digital devices with Boolean signals correction and weight-based Bose–Lin codes. Unlike previous studies, the method involves Boolean signals correction (BSC) in the concurrent error-detection (CED) circuit for those functions describing the outputs of source devices that participate in the formation of data symbols of weight-based Bose–Lin codes. In such codes, as in the absolute majority of uniform separable codes, several data vectors correspond to the same check vector; therefore, it is possible to choose a method for determining BSC functions. We describe an algorithm for determining their values for each input combination, considering the testability of the checker and transformation elements in the CED circuit. The method involves the so-called “base” structure for monitoring multi-output devices by output groups. With this method, the designer of a self-checking device has high variability in choosing the design method and can regulate important indicators (structure redundancy, controllability, energy consumption, and others). Experiments with combinational benchmarks from MCNC Benchmarks were carried out. According to the experimental data, the method has high efficiency in terms of structure redundancy compared to the duplication method widespread in practice. The method can be effective when designing real devices with fault detection used in all areas of technology, including critical application systems in industry and transport.
ИСПЫТАНИЯ ИНЕРЦИОННЫХ ДАТЧИКОВ ДЛЯ КРЕНОВАНИЯ В СТАТИКЕ
Authors: В. АРТЕМЬЕВ А , А. ГОРШКОВ А , А. ОСЬКИН Д , С. ГРОМАШЕВА О , Х. ХАЙДАРОВ З
Published: October 2024

В статье обзор конструкций цифровых датчиков угла наклона, выбор датчиков, и экспериментальная проверка (стендовые испытания) соответствия заявленных характеристик датчика с его реальными возможностями. По результатам работы определены критерии точности измерительных приборов необходимых для надежного определения углов крена судна, учитывая характер движения порожнего судна на воде.

The article provides a review of the structures of digital tilt angle sensors, the choice of sensors, and an experimental testing (bench tests) of the compliance the declared characteristics of the sensor with its real capabilities. Based on the results of the work, the criteria for the accuracy of measuring instruments necessary for reliable determination of the ship's roll angles, taking into account the nature of the movement of an empty vessel on the water, are determined.
ОСОБЕННОСТИ ОРГАНИЗАЦИИ ОБМЕНА ДАННЫМИ ДЛЯ АВТОМАТИЗИРОВАННОГО ЛАБОРАТОРНОГО РОСТОВОГО КОМПЛЕКСА «RUBITEK»
Authors: А. ЮСИМ В , Э. САРКИСОВ С , В. ЧАУСОВА О , Е. ТРУБИН А , А. БУЛАНОВА Т , А. БУЛАНОВ В , Г. ГОЛУБЕВ В
Published: October 2024

Исследованы особенности использования промышленных протоколов передачи данных на примере эксплуатации автоматизированного ростового комплекса «RUBITEK». Проведен системный анализ основных современных протоколов промышленной автоматизации -Modbus RTU/TCP, ОВЕН, PROFIBUS/NET и др. Определены наиболее подходящие протоколы для использования в ростовом комплексе, исходя из задач автоматизации. Рассмотрены вопросы обеспечения реализации выбранных промышленных протоколов в рамках комплекса.

Within the framework of this publication, the process of developing software for the laboratory growth complex "Rubitek" is considered, in the initial stage of product deployment. The "Kanban" project management methodology has been selected and described. The choice of IDEs for software development is justified, and the choice of programming languages is also justified. The implementation of the Kanban methodology in the process of creating software for the growth complex is shown.