16168 research outputs found
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Development and research of control algorithm for selective non-catalytic reduction of nitrogen oxides.
No full textThe final master's project investigated the control of the SNCR process in an industrial biomass fuel boiler. The fuel used in this boiler is wood pellets and bagasse - sugarcane waste. A mathematical model of the process was created in the Ovation DCS distributed control system, including the formation of nitrogen oxides from burning fuel and thermal, SNCR reduction, ammonia reagent injection and ammonia slip processes. The main goal of the study is to create a SNCR control method that would replace the existing one and would respond to fuel moisture. For this, a fuzzy logic control system with Smith predictor was used that replaced the existing prescription control. The inputs to the designed controller are the temperature of the boiler reaction zone, steam flow (steam load) and biofuel moisture. The signal output of the controller is urea flow. This urea, reacting with nitrogen oxide, reduces them and thus reduces the amount of pollutants entering the atmosphere to the required limit
Developing and researching a Python programming fundamentals tutorial.
No full textThe main goal of the master's thesis is to create an intuitive and innovative distance learning system for beginner programmers to learn programming. The results of the conducted research showed that there is a problem that it is too difficult to start learning programming without initial knowledge and skills, that is, by retraining, or to gain qualifications and competence in a new field. To solve the problem, it is important to consider the survey results and use an intuitive and easy-to- understand programming environment that does not require additional time to learn. It is crucial to design programming tasks appropriately so that they are not overly complex and each task provides value in the learning process. The tasks should motivate and encourage the learner, therefore they need to be engaging and non-repetitive. The virtual learning environment should allow learners to choose their workload based on their abilities, progress, and motivation
Comparison of the pilling resistance of linen and hemp woven fabrics /
No full textGood comfort properties and biodegradability are characteristic of linen fabrics. However, hemp fabrics also have high comfort properties, but hemp has been rarely used for textile manufacturing for a long time due to myths about its opiate effect. Today, a special species of hemp which does not have the above-mentioned effect has started to be cultivated again. Hemp fiber from these plants is being used for textile production. Therefore, it is very important to study the properties of hemp fabrics and compare them with those of other known cellulosic fibers such as linen. The aim of this study was to investigate the pilling resistance of linen, hemp, and linen/hemp woven fabrics before and after anti-pilling finishing. Linen, hemp and linen/hemp woven fabrics of plain weave from linen and hemp spun yarns of 28 tex linear density in the warp and weft directions before and after anti-pilling treatment with enzyme BEIZYM UL were investigated. A Martindale pilling and abrasion tester MESDAN-LAB, Code 2561E was used for pilling tests in accordance with the standard LST EN ISO 12945-2:2000. The pilling grades for blended linen and hemp fabric decreased from 0.5 grade after 125 cycles to 1.5 grade after 2000 cycles, whereas they remained constant at 1.0 grade after 2000 cycles for linen fabrics. The use of BEIZYM UL enzymes in additional fabric treatments increased the pilling resistance to 1.0 grade for linen fabric and 0.5 grade for hemp and blended linen/hemp fabrics. In conclusion, hemp fabric is the most resistant to pilling. Thus, a linen-hemp blend can significantly enhance linen fabric pilling resistance. The finishing process improves the pilling performance of fabrics of all raw materials. The finishing has the greatest influence on linen fabric pilling resistance and the least on hemp fabric pilling resistance because the usual finishing improves the pilling performance of hemp fabric more than the additional enzymatic treatment
Investigation of energy storage device application for provision of system services.
No full textThis paper analyses the application of battery energy storage systems (BESS) in electricity markets to assess their economic potential and technical applicability. The literature analysis has shown that among the different technologies, lithium-ion batteries currently have the highest practical potential and are able to operate efficiently in both arbitrage and frequency support markets. Based on data from the Finnish electricity market, an optimisation model has been developed that allows planning the operation of the BESS taking into account technical constraints and price dynamics. An economic evaluation based on the model showed that BESS can be a financially attractive investment, especially in more flexible market conditions. At the same time, it was found that the appropriate choice of operating scenarios and charging costs are crucial for the profitability of a storage system, which has a significant impact on the efficiency of the system
The impact of sensor application site on continuous noninvasive haemoglobin trends /
No full textPurpose: This prospective observational clinical study investigated discrepancy between noninvasive continuous haemoglobin (SpHb, Masimo Corp., Irvine, CA) measurements with sensors placed on three fingertips during elective cardiac surgery. Materials and methods: The study included 12 adult patients who underwent elective coronary artery bypass grafting (CABG) under cardiopulmonary bypass (CPB). Three identical versions of SpHb sensors were placed on the fingers of the same hand and connected to dedicated Masimo Radical-7 monitors. Data were continuously recorded throughout the surgery. Multiple group comparison tests—Kruskal–Wallis and Alexander–Govern tests—were used to compare three sets of SpHb data (trends). Bland–Altman and Giavarina plots were used to compare the SpHb data with invasive arterial haemoglobin (Lab-Hb) data obtained at clinically relevant time points chosen at the discretion of the cardiac anaesthesiologist, who was blinded to the study protocol. Results: There was a good correlation between the time-matched SpHb data from the three sensors at 253 time points (r = 0.86–0.95), but there was a significant difference between the SpHb values obtained from each sensor and the average SpHb value of all 3 sensors (p < 0.05) at each time point. The absolute difference between the SpHb value obtained from each sensor and the average SpHb value was 0.69 g/dl g/dl (SD 1.49 g/dl). The accuracy and precision of the average SpHb for estimating Lab-Hb was higher compared to the SpHb values obtained from two out of three individual sensors (sn1 and sn3) and very similar compared to values obtained from sensor sn2. Conclusion: The sensor placement site can impact the SpHb measurement causing discrepancy between SpHb measured in different fingers. The average SpHb from three fingertips appears to be more accurate and precise in estimating Lab-Hb. However, more advanced sensors are needed
The expression of leadership styles among managers in the Lithuanian healthcare sector.
No full textThe article presents a study on leadership styles applied in the Lithuanian personal healthcare sector. This sector faces numerous challenges, including a shortage of specialists, heavy workloads, increasing employee mobility, and widespread burnout syndrome. These problems are further exacerbated by ongoing healthcare reforms and a complex healthcare institution management system. Leadership in this sector is critically important, and its effectiveness is largely determined by the leadership style adopted by managers, which can directly influence institutional outcomes, employee motivation, commitment, and organizational culture. The aim of this study is to identify the leadership styles applied by managers in the healthcare sector. To achieve this, a quantitative study was conducted, surveying 422 respondents working in healthcare institutions. The results revealed that the dominant leadership style among Lithuanian healthcare managers is passive leadership, characterized by limited managerial involvement, delegation of autonomy, and promotion of employee independence. The study also identified commonalities and differences in leadership styles between managers in the public and private sectors of healthcare institutions. Although passive leadership is prevalent across all types of healthcare institutions, transformational leadership is more strongly expressed in public institutions, suggesting that public sector leaders are more focused on building authority, motivating employees, providing support, and fostering development
Development and validation of a simplified system for upper limb motion analysis and rehabilitation biofeedback /
No full textEmpowering industry 5.0: a multicriteria framework for energy sustainability in industrial companies /
No full textIndustry 5.0 introduces a transformative vision for manufacturing by emphasizing human-centricity, sustainability, and resilience in tandem with advanced technologies. While Industry 4.0 focused on automation and connectivity, Industry 5.0 shifts the paradigm toward enhancing human involvement, environmental responsibility, and adaptive capacity. Despite growing interest, there remains a lack of standardized metrics for evaluating Industry 5.0 implementation within companies. This paper proposes a comprehensive multicriteria evaluation framework to assess a company’s alignment with Industry 5.0 principles across ten key criteria from the human-centricity, sustainability and resilience sectors. A structured scoring system—ranging from A (full alignment) to E (no alignment)—was developed to quantify implementation maturity. The framework was applied to a medium-sized Lithuanian manufacturing company specializing in furniture components, providing a real-world case study to validate the method. The company received a low Industry 5.0 score, indicating poor alignment; however, targeted recommendations were proposed that could improve the score by nearly 70%, moving the company toward a well-aligned status. This study offers a practical tool for evaluating and guiding Industry 5.0 transitions in manufacturing contexts
Synthesis and biological evaluation of alkylated 2-mercaptoimidazoles bearing a benzenesulfonamide moiety /
No full textBenzenesulfonamides are widely explored due to their wide range of potential pharmaceutical uses as anticancer, antibacterial drugs [1]. As well as functionalized 2-mercaptoimidazoles which present potent anticancer activity [2]. In this present study, α-aminoketone 2 was obtained by reacting the primary amine 1 with bromoacetophenone, which in turn was reacted with potassium thiocyanate in the presence of hydrochloric acid to obtain 2-mercaptoimidazole 3. Compounds 4-13 were synthesized by alkylating 2-mercaptoimidazole 3 with a corresponding bromoacetophenones in methanol at reflux, using sodium bicarbonate as a weak base. Similarly, compound 14 was yielded by performing an alkylation with 4-nitrochlorobenzene in dimethylformamide using potassium hydroxide as a strong base, as well as potassium carbonate. Ester 15 was obtained by alkylating 2-mercaptoimidazole 3 with methyl bromoacetate in ethanol in presence of potassium carbonate and in turn was hydrolyzed with a sodium hydroxide solution to obtain carboxylic acid 16. Benzimidazoles 17, 18 were prepared by condensing corresponding benzenediamines with an ester in presence of hydrochloric acid. The structure of the synthesized compounds was characterized by spectral data (IR, NMR spectra, and elemental analysis)