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B. Marković, Vidak Čajević, A. Đurić, Srđan Samardžić

The paper presents the method of using the solution selection method in developing a new concept of the BOBCAT E62 excavator control handle, with the aim of implementing a lightweight design. The lightweight design concept is used in various industries, including the design, i.e. construction of construction machinery, where the use of modern materials and design methods can lead to an optimal solution, while maintaining load-bearing capacity and functionality. The modified handle design solution aims to reduce weight, without major changes to other parts of the assembly of which it is a component. Two methods were used to assess the concept selection, as an integral part of the product development process, i.e. the solution selection phase. The selected concept solution should contribute to improvements in terms of durability, compactness and reduced energy consumption.

D. Klobčar, U. Trdan, Mirza Imširović, D. Bračun, Mohammad REZA GHAVI, T. Vuherer, Marek Polański, A. Đurić et al.

Directed Energy Deposition (DED) processes offer the advantage of producing larger parts with higher deposition rates compared to Powder Bed Fusion (PBF) additive manufacturing (AM). However, DED typically results in simpler geometries and lower resolution. When using Wire and Arc- based DED, even larger components can be manufactured at an accelerated rate, but the higher heat input may lead to undesirable microstructures, adversely affecting mechanical properties. To ensure defect-free depositions, precise process control is essential, including optimizing deposition paths, regulating inter-layer temperature, and maintaining a consistent nozzle-to-layer distance. One effective approach to improving material integrity is the application of in-situ vibrations during deposition. This technique helps reduce porosity and grain size while also enhancing surface waviness and mitigating residual stress buildup. Further refinement of material properties can be achieved through appropriate thermo-mechanical processing, leading to mechanical characteristics comparable to conventionally produced steel. This paper explores the impact of in-situ vibrations and heat treatment through case studies, analysing their effects on surface waviness, residual stress distribution, porosity, microstructure, grain size, mechanical properties, and fracture toughness. The findings demonstrate the significant benefits of these process enhancements in improving the mechanical performance of DED- fabricated components.

A. Đurić, B. Marković, Srđan Samardžić, D. Milčić, D. Klobčar, M. Milčić

Nanostructured adhesives represent a paradigm shift in bonding technology, leveraging the unique physicochemical properties of nanoscale materials to enhance adhesive performance. This review examines the fundamental principles underlying nanostructured adhesive design, focusing on the role of nanoparticles, nanofillers, and nanocrystals in improving mechanical properties. Furthermore, this paper will explore the diverse applications of nanostructured adhesives across industries, including aerospace, automotive, electronics, and biomedicine, highlighting the potential for tailored adhesive solutions.

Srđan Samardžić, D. Klobčar, A. Đurić, B. Marković

Additive manufacturing enables the production of parts with complex geometries that would be difficult or impossible to produce with conventional manufacturing technologies – and with minimal waste. A more massive use of additive technologies makes it possible to shorten supply chains and reduce the need to store parts. Fixtures are essential production aids that position, hold and support workpieces, ensuring positioning accuracy, repeatability and operator safety during assembly and bonding. This paper presents how the Fused Deposition Modeling (FDM) process can provide such fixtures for the adhesive bonding of metal parts in rail vehicle composite structures. By adapting geometry, surface properties and ergonomics to the bonding task at hand, FDM fixtures improve alignment accuracy and simplify handling.

E. Hukić, M. Kašanin-Grubin, M. Subašić, Tomislav B Tosti, Svetlana Djogo-Mracevic, S. Štrbac, S. Stojadinović

This study investigates the impact of drying-rewetting and freezing-rewetting events on soil leachate ion composition across two contrasting geochemical settings through a series of controlled laboratory experiments. Dissolution of ions (Na?, K?, Ca??, Mg??, Al??, Fe??, Mn??, F?, Cl?, NO??, SO???, NO??, PO???) in soil leachate was analyzed following rewetting cycles after drying and freezing treatments. Results indicate that variations in leachate ion concentrations are primarily influenced by bedrock type, while drying-rewetting and freezing-rewetting treatments did not significantly impact overall variance. However, some inconsistent differences were observed: higher K? concentrations in calcareous soils and Al??, Fe?? and Mn?? in acidic soils after drying, higher anion concentrations in calcareous soils in both treatment leachates compared to controls. Findings highlight that the effects of drying, freezing, and rewetting are inherently linked to treatment type, ion characteristics, and geochemical conditions.

Hamidović Dostović, F. Skokić, S. Muratović, Asja Terzić

Background: Maternal anaemia is one of the most common complications of pregnancy and is associated with adverse outcomes such as preterm delivery, impaired fetal development, and increased risks of morbidity and mortality in the perinatal period. The high prevalence of anaemia in pregnancy and its impact on fetal development represents a significant public health issue. The aim of this study was to analyze the influence of maternal anaemia on neonatal outcomes. Patients and Methods: In a two-year prospective study conducted at the Clinic of Gynecology and Obstetrics and the Clinic of Children's Diseases of the University Clinical Center Tuzla, 177 newborns and their mothers were analyzed-127 in the experimental group (mothers with anaemia) and 50 in the control group (without anaemia). Sociodemographic and clinical data of the mothers and newborns were collected. Data were processed using conventional statistical techniques. Ethical approval was obtained from the relevant institutional review board. Results: Of the 120 (70.58%) mothers with anaemia included in the study, 106 (88.3%) were between 18 and 35 years of age. Working mothers had lower odds of anaemia (p = 0.025), while mothers who did not use supplements during pregnancy had higher odds (p = 0.001). Maternal anaemia was significantly associated with smoking or tobacco use (p = 0.015). Mothers living outside of marriage were more likely to be anaemic. A higher percentage of vaginal bleeding (p = 0.0001), uncontrolled pregnancies (p = 0.011), and caesarean section as the mode of delivery (p = 0.000) were recorded among anaemic mothers. Babies born to anaemic mothers had lower birth weight compared to those born to non-anaemic mothers (p = 0.004). Maternal anaemia significantly affected gestational age (p = 0.024) and Apgar scores in the 1st (p = 0.006) and 5th minutes (p = 0.0031). In this study, maternal anaemia during pregnancy had a statistically significant impact on perinatal outcomes including perinatal asphyxia, respiratory distress syndrome, neonatal infections, icterus neonatorum, intracranial hemorrhage, and hypoxic-ischemic encephalopathy. Conclusion: In developing countries, current strategies for the prevention of anaemia in pregnancy have had limited success. Programs for careful monitoring and management of anaemia during pregnancy need to be developed in order to prevent poor perinatal outcomes.

Aleksandar Tomović, Remzo Dedic, A. Vučina, N. Rašović, R. Tomović, Milanko Damjanovic

This paper analyzes the development of an above-knee prosthesis based on hydraulic actuators, which was initiated at the Faculty of Mechanical Engineering, Computing and Electrical Engineering at the University of Mostar, and has continued since 2023 in collaboration with the Faculty of Mechanical Engineering of the University of Montenegro. The evolutionary trajectory of the prosthetic design is presented, from the initial models with a single hydraulic cylinder in the knee joint, through the integration of an additional actuator in the ankle joint and modifications to the prosthetic foot, to modern solutions featuring double-acting cylinders and separate hydraulic power units. Experimental testing has confirmed significant improvements in user stability, functionality, and natural gait, especially when ascending stairs. The paper also emphasizes future development directions, including the implementation of servo valves in the hydraulic system to achieve more precise fluid control, smoother movements, and automatic adaptation of the prosthesis to varying walking conditions. The research results indicate that hydraulic systems represent a significant technological advancement in modern prosthetics, enabling transfemoral amputees greater independence, comfort, and quality of life.

Faisal Hassan, Eldar Šaljić, Ema Kraktus

Climate change is one of the main challenges facing the population around the world. The consequences of these changes have been manifested for decades in various ways, creating disasters that threaten the lives of an increasing number of people. This paper analyses the consequences of the floods that hit the United Arab Emirates on April 16, 2024. After any natural disaster, this flood also calls into question the approach, preparedness and response to this challenge, questioning the success of managing critical infrastructure. This is an important question given that in the last two decades the United Arab Emirates has encountered several floods of a more serious scale. In line with the further development of the consequences of climate change and in response to the challenges they bring with them when it comes to the United Arab Emirates, the authors also propose specific guidelines for the relevant institutions as a way of improving critical infrastructure. A significant area would be to focus on the latest technology in creating superior public-private partnerships that would become modern, national-integrated emergency management systems. The authors used the Risk Management Theory, suggesting ways in which preventive responses can be made. The authors also used content analysis, as well as the observation method.

Introduction: The mechanisms of pulmonary embolism in patients with metabolic syndrome has not been fully investigated. The aim of the study was to determine the connection between metabolic syndrome and pulmonary embolism and to evaluate the values of the glucolipid profile in patients with pulmonary embolism in metabolic syndrome. Methods: A cohort study included 305 patients with pulmonary embolism, divided into two groups: the first group with metabolic syndrome (n=165) and the control group without metabolic syndrome (n=140). The data was collected from May 2019 to May 2023. Demographic, anthropometric and laboratory parameters (glucose, total cholesterol, HDL cholesterol, LDL cholesterol, triglycerides) were analyzed in all patients with confirmed pulmonary embolism. Results: Patients with pulmonary embolism in metabolic syndrome had statistically significantly higher values of glucose, total cholesterol, LDL cholesterol, triglycerides and lower values of HDL cholesterol compared to patients with pulmonary embolism without metabolic syndrome (p<0.05). Discussion: The results of our research indicate a strong need for a broad evaluation of metabolic abnormalities with special highlight on comorbidities and the need for a multidisciplinary approach to patients with metabolic syndrome. Assessing the risk of pulmonary embolism should become imperative in the treatment of patients with metabolic syndrome. Conclusion: Metabolic syndrome may play a key role in the pathogenesis of pulmonary embolism and may be a link between venous thrombosis, atherosclerosis and pulmonary embolism. Due to the complex relationship between hyperglycemia, dyslipidemia and pulmonary embolism, additional research is necessary to answer the question why people with metabolic syndrome have a higher risk of pulmonary embolism, as well as to determine appropriate preventive strategies.

Branka Ružičić, D. Grujić, Aleksandar Savić, L. Topalić-Trivunović, Ana Velemir, Blanka Škipina, S. Dedijer, M. Prica

The growing need to reduce the negative impact on the environment and human health, as well as to meet the growing demand for eco-friendly textiles, has led to the development of environmentally friendly printing techniques and the use of natural dyes in the textile industry. Grape pomace is important waste material in winemaking, and has been extensively studied for its potential as a source of compounds with biological properties, especially anthocyanins, pigments responsible for the red, purple, and blue colors in grapes. The aim of this paper was to examine the potential use of natural dye extracted from grape pomace of domestic cultivar crna Mirisavka (GPCM) in preparation of printing paste with alginate, citric acid, and tannic acid for printing on cotton fabric. Special focus was placed to achieve process color magenta, by adjusting the pH value of the extract obtained. The natural dye from GPCM was extracted using maceration with 80% methanol, followed by sonication to enhance the yield of bioactive compounds. GPCM extract demonstrated significant antioxidant activity measured by FRAP, DPPH, and ABTS+ tests, and moderate antibacterial activity against Staphylococcus aureus and Escherichia coli. The pH-dependent stability of anthocyanins in GPCM extract was examined, demonstrating a magenta tone at acidic pH (pH 2-4) and color degradation at higher pH values. Cotton fabric printed with two different concentrations of GPCM extract (100 mg/L and 50 mg/L) showed good antioxidant and antibacterial activity. Based on the obtained results, it can be concluded that GPCM extract can be an environmentally friendly solution for the development of antibacterial and antioxidant textiles, with potential application in the production of protective clothing in healthcare institutions, as well as for the production of decorative home textiles, for the production of children's toys and textiles for packaging.

Short-wave infrared radiation allows for efficient heating of a body (target) with minimal thermal interaction with the gaseous medium through which it passes. The mutual geometric relationship between the infrared heating source and the target impacts the spatial resistances of radiation heat transfer. Therefore, a significant portion of the short-wave infrared radiation emitted by the heat source does not reach the target, thereby reducing its efficiency. To maximize the use of thermal radiation, this study analyzes a profiled nanofluid collector on which a heated target is placed. Nanofluid with Al2O3 nanoparticles flows through internal arrays of round nozzles and a profiled housing, being heated by the inner surface of the collector. The paper establishes a methodology based on the thermal irreversibility of the heat source, collector and nanofluid. The established methodology allows for minimizing thermal entropy in order to optimize the geometric and process parameters of the described system. The results of the conducted analysis are based on the cross-influence of the Reynolds number of the nanofluid, target and collector emissivity, short-wave heating time and nanoparticle volumetric ratio. The results obtained indicate that as the target emissivity, heater temperature and heating time increase, the thermal entropy of the mutual interaction between the heater and the target also increases significantly. Similarly, the thermal entropy of the mutual interaction between the collector and the nanofluid is greatly influenced by factors such as the Reynolds number (from 2000 to 4000), volumetric ratio (3% and 5%) and type of nanoparticles used (Al2O3, TiO2, and CuO). In this way, the specially designed collector allows for the utilization of captured heat, while the established methodology offers the opportunity to optimize the process-geometric parameters of the heating system being analyzed.

Vera Karličić, Merima Makaš, Milica Ćopić, Iva Atanasković, I. Kljujev, Monika Stojanova, Blažo Lalević

Sewage sludge is a by-product of wastewater treatment. Sewage sludge is a desirable material for application in agriculture production as a fertilizer or soil conditioner, as it is characterized by a high content of organic matter and nutrients such as nitrogen, phosphorus and potassium. However, sewage sludge tends to concentrate trace metals, organic pollutants and pathogenic organisms due to the initial pollutant load of the treated wastewater and the treatment processes. Although various chemical methods can be used to remove trace metals from sewage sludge, the use of microbes is considered a more cost-effective and environmentally friendly approach compared to chemical treatments. This review examines the risks of trace metals in the application of sewage sludge and demonstrates the efficiency of their removal using physical, chemical and biological methods.

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