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Cardiovascular risk factors in middle-aged Lithuanian men: a comparative study of an apparently resistant hypertension group /
No full textBackground/Objectives: Hypertension (HTN) is a significant risk factor for cardiovascular disease (CVD), and a subset of patients exhibits apparently resistant hypertension (aRHTN), where blood pressure remains inadequately controlled despite treatment. This study aims to assess the prevalence of cardiovascular risk factors in middle-aged Lithuanian men with HTN and aRHTN, as well as to evaluate the effectiveness of hypertension management in these groups. Methods: Data from 52,012 men participating in the Lithuanian High Cardiovascular Risk Programme (LitHiR) between 2009 and 2019 were analysed. Participants were categorised into two groups: treated hypertension (HTN) and apparent resistant hypertension (aRHTN). Despite treatment, the aRHTN group included those who failed to achieve their target blood pressure. The prevalence of cardiovascular risk factors (dyslipidaemia, diabetes, metabolic syndrome, obesity, physical inactivity, and an unbalanced diet) was compared between the groups. Results: The overall prevalence of HTN was 47%, with 9.9% of treated hypertensive men having aRHTN. Dyslipidemia was both groups' most prevalent risk factor (94.1% in HTN vs. 95.5% in aRHTN, p < 0.001). Men with aRHTN exhibited higher rates of diabetes (25.9% vs. 18.5%, p < 0.001), metabolic syndrome (75.3% vs. 66.3%, p < 0.001), and left ventricular hypertrophy (59.4% vs. 43.1%, p < 0.001). Treatment success was significantly lower in the aRHTN group (7.57% vs. 28.4%, p < 0.001). Conclusions: Hypertension affects almost half of the studied population, with 10% of treated hypertensives exhibiting aRHTN. The aRHTN group had a higher number of additional cardiovascular risk factors and lower treatment success rates. Improved management of cardiovascular risk factors is crucial, especially in the aRHTN population, to reduce the burden of CVD
Patterns in heuristic optimization algorithms: a comprehensive analysis /
No full textHeuristic optimization algorithms have been widely used in solving complex optimization problems in various fields such as engineering, economics, and computer science. These algorithms are designed to find high-quality solutions efficiently by balancing exploration of the search space and exploitation of promising solutions. While heuristic optimization algorithms vary in their specific details, they often exhibit common patterns that are essential to their effectiveness. This paper aims to analyze and explore common patterns in heuristic optimization algorithms. Through a comprehensive review of the literature, we identify the patterns that are commonly observed in these algorithms, including initialization, local search, diversity maintenance, adaptation, and stochasticity. For each pattern, we describe the motivation behind it, its implementation, and its impact on the search process. To demonstrate the utility of our analysis, we identify these patterns in multiple heuristic optimization algorithms. For each case study, we analyze how the patterns are implemented in the algorithm and how they contribute to its performance. Through these case studies, we show how our analysis can be used to understand the behavior of heuristic optimization algorithms and guide the design of new algorithms. Our analysis reveals that patterns in heuristic optimization algorithms are essential to their effectiveness. By understanding and incorporating these patterns into the design of new algorithms, researchers can develop more efficient and effective optimization algorithms
Prediction of approaching trains based on H-ranks of track vibration signals /
No full textThis paper introduces a method for forecasting the arrival of trains by analyzing track vibration signals. The proposed algorithms, based on H-ranks of track vibration signals, can generate early alerts for approaching trains. These algorithms are robust to additive noise and environmental conditions. The theoretical foundation of the method involves the application of matrix operations to detect significant changes in vibration patterns, indicating an approaching train
From caged robots to high-fives in robotics: exploring the paradigm shift from human–robot interaction to human–robot teaming in human–machine interfaces /
No full textMulti-modal human–machine interfaces have recently undergone a remarkable transformation, progressing from simple human–robot interaction (HRI) to more advanced human–robot collaboration (HRC) and, ultimately, evolving into the concept of human–robot teaming (HRT). The aim of this work is to delineate a progressive path in this evolving transition. A structured, position-oriented review is proposed. Rather than aiming for an exhaustive survey, our objective is to propose a structured approach in a field that has seen diverse and sometimes divergent definitions of HRI/C/T in the literature. This conceptual review seeks to establish a unified and systematic framework for understanding these paradigms, offering clarity and coherence amidst their evolving complexities. We focus on integrating multiple sensory modalities — such as visual, aural, and tactile inputs — within human–machine interfaces. Central to our approach is a running use case of a warehouse workflow, which illustrates key aspects including modelling, control, communication, and technological integration. Additionally, we investigate recent advancements in machine learning and sensing technologies, emphasising robot perception, human intention recognition, and collaborative task engagement. Current challenges and future directions, including ethical considerations, user acceptance, and the need for explainable systems, are also addressed. By providing a structured pathway from HRI to HRT, this work aims to foster a deeper understanding and facilitate further advancements in human–machine interaction paradigms
Research of application possibilities of additive manufacturing technologies for producing plastic prototypes at company X.
No full textThis master's thesis evaluates the possibilities of applying additive manufacturing technology to produce plastic prototypes at company X. The project aims to investigate whether AM can be an effective alternative to the existing prototype production technology, which uses CNC milling machines HASS VF 3SS. The possibilities are assessed by production time, quality, design flexibility, production costs, and the efficiency of material use. The first part of the work includes a literature review, which examines the advantages and disadvantages of traditional manufacturing technologies and AM. The CNC milling technology used by company X is also evaluated. It was found that although prototypes produced using CNC technology meet high-quality requirements, they require high costs and flexibility. AM technology, such as FDM printing, offers an alternative that allows reducing material waste, speeding up processes, and maintaining quality at the same time. During the work, a sequence of technological operations of the AM process was created, and adapted to the production of plastic prototypes. This sequence includes the creation of a 3D model in a CAD environment, optimization of the model using PrusaSlicer software, and production using the Original Prusa Mini+ 3D printer. Various experimental studies used in the work have shown that AM technology can ensure sufficient quality of prototypes, and their production time and costs are significantly lower than when produced by CNC milling machines. In addition, the project provides a calculation of the overall efficiency of CNC milling equipment, using data from the last year, collected from available production data sources. The physical properties of parts produced by CNC milling and AM technology are also compared and different measurements are performed to determine the differences in surface roughness, contours, hardness, and surface deviation. The results of the economic assessment showed that it could be beneficial for company X to integrate AM technology into production processes, as this would allow optimizing prototype production and reducing costs. At the end of the work, 4 conclusions are presented, emphasizing the potential of AM technology to change traditional plastic prototype production practice at company X
Influence of Na2SO4 produced from phosphogypsum conversions on the basic properties of building gypsum /
No full textThis study comprises two distinct but interrelated parts. The first part involves optimizing the conditions for the conversion of phosphogypsum to a Ca(OH)2 and Na2SO4 solution. The second part focuses on enhancing the mechanical properties of gypsum through the use of a sodium sulphate additive derived from the conversion of phosphogypsum. An ultrasonic disperser was employed to accelerate the reaction between phosphogypsum and a sodium hydroxide solution. The mean dispersion time was found to be 0.2, 0.5, 1.0, and 2.0 min. The resulting product was a solution of calcium hydroxide and sodium sulfate. The impact of varying quantities of Na2SO4 on the compressive strength and density of building gypsum samples was investigated. An increase in the quantity of sodium sulphate from 0.2% to 2% resulted in a notable rise in the density of the building gypsum samples, from 1127 kg/m3 in the reference sample to 1264 kg/m3 in the sample containing 2% sodium sulphate. Therefore, in all instances, the utilization of the Na2SO4 additive in the gypsum samples resulted in elevated compressive strengths (4.8-8.6 MPa) in comparison to the reference sample devoid of this additive (1.6 MPa)
Comparative analysis of the efficiency of double skin metal faced insulating wall panels.
No full textThe construction sector faces increasingly stringent requirements for energy efficiency and structural stability, making multilayer wall panels one of the primary materials used in industrial buildings. These panels are valued for their lightness, structural efficiency, and excellent thermal insulation properties. This master’s thesis conducts a performance analysis of different multilayer wall panels using the TOPSIS multi-criteria evaluation method. The study aims to determine the most rational panel alternative based on structural stability, energy efficiency, resistance to mechanical loads, and other important criteria. The master’s thesis consists of an introduction, three chapters, conclusions and recommendations, a list of references, and appendices. The introduction discusses the relevance of the work, the research objectives, tasks, and methodology. The structure and content of the work are described in detail, and the research is based on a review of scientific literature. The first chapter examines scientific literature on the properties and applications of multilayer wall panels. The chapter reviews the thermal insulation, mechanical load resistance, and fire protection parameters of these panels. Information about European standards EN 14509 and EN 13501-2, which regulate the performance properties and requirements of panels, is provided. The second chapter describes the research methodology, detailing the TOPSIS multi-criteria evaluation method. It outlines the criteria selection basis and principles for determining their weights. The study uses the design software "Autodesk Revit," and data analysis is conducted using the "Design Tools – Traypan" software, which allows precise evaluation of structural characteristics. The third chapter presents the research results and their analysis. It compares the structural and operational performance of different types of multilayer panels. Based on the results, it was found that panels with mineral wool cores exhibit higher fire resistance, while polyurethane panels are more efficient in terms of thermal insulation. The TOPSIS method enabled the identification of the most rational choice based on the established criteria. The findings of this work emphasize the importance of multilayer panels in ensuring energy efficiency and structural stability. The provided recommendations could be applied in the design and construction processes to optimize the construction and operation of industrial buildings
Schumann resonances and the human body: questions about interactions, problems and prospects /
No full textFeatured Application: This review should strengthen the transdisciplinary dialogue between scientists for further studying the influence of the Earth’s magnetic field on the human body. This review should draw attention to the issue among biomedical scientists and physicians. (1) Background: The interaction between the human body and the Earth’s magnetic field at Schumann resonances (SRs) is one of the important fundamental questions of science that continues to be studied. The aim of this study was to create a working theoretical foundation for the interaction of the human body with SRs. (2) Methods: Extensive research was carried out in the literature with the aim of comprehensively presenting data on SRs and creating a working concept of their interaction with the human body. (3) Results: General data on SRs, a theoretical basis for justifying their interaction with the human body, possible mechanisms of influence and research results on the functioning of human internal organs were presented. (4) An interaction of the human body with SRs exists and has been scientifically proven. This interaction has been studied most significantly between SRs and the human nervous system. SRs affect functional indicators of the cardiovascular system: heart rate and blood pressure. Studying the influence of SRs on the course and pathogenesis of non-communicable diseases is a promising direction. Low-frequency SRs decrease the risk of developing acute myocardial infarction, and there is a tendency for them to promote cases of chronic kidney disease. SRs are an important external natural factor influencing the human body
A study on the assessment of sustainable materials in buildings.
No full textGlobal and international requirements due to poor environmental conditions and significant climate change are forcing the construction industry to use sustainable materials. Sustainable materials can also include organic materials, such as wood or mass wood products. The Ministry of Environment of the Republic of Lithuania has issued an order stating that from 2024. November 1 public buildings will have to be built using at least 50% of timber or other organic materials. It is important to provide a clear and logical methodology for the assessment, how and by what means the percentage of organic materials in a building can be estimated. One of the convenient ways is to use building information modeling tools and 3D modeling. Sustainable and unsustainable 3D models were designed for the study using the Autodesk Revit program package. The ontologies of the National Building Information Classifier were used to identify the building elements. Environmental product declarations submitted by manufacturers were used to assess the sustainability of buildings and project parameters were created for assessment. Based on the quantity worksheets of the designed structures, the total values of 7 main indicators of the environmental impact of materials were calculated and the sustainability of the structures was determined. The essential parameter “Organic material” was created, which allowed the authors to sort the structure into organic and inorganic. The formulas created by the authors required the volumes of organic and inorganic materials, which were used to assess the percentage of organic materials in the structures. The percentages of organic materials are calculated based on the authors' methodology and the methodologies proposed by the Ministry of the Environment of the Republic of Lithuania. It was determined that based on the authors' methodology, more accurate results were obtained, while based on the methodology of the Ministry of the Environment of the Republic of Lithuania, coarser results were obtained