AI-driven data analysis methods have garnered attention in enhancing the performance of wireless networks. One such application is the prediction of downlink throughput in mobile cellular networks. Accurate throughput predictions have demonstrated significant application benefits, such as improving the quality of experience in adaptive video streaming. However, the high degree of variability in cellular link behaviour, coupled with device mobility and diverse traffic demands, presents a complex problem. Numerous published studies have explored the application of machine learning to address this problem, displaying potential when trained and evaluated with traffic traces collected from operational networks. The focus of this paper is an empirical investigation of machine learning-based throughput prediction that runs in real-time on a smartphone, and its evaluation with video streaming in a range of real-world cellular network settings. We report on a number of key challenges that arise when performing prediction “in the wild”, dealing with practical issues one encounters with online data (not traces) and the limitations of real smartphones. These include data sampling, distribution shift, and data labelling. We describe our current solutions to these issues and quantify their efficacy, drawing lessons that we believe will be valuable to network practitioners planning to use such methodologies in operational cellular networks.
The additive technologies such as 3D printing are an important part of all branches of industry, primarily due to the possibility of production parts with complex geometries. The aim of the research presented in this paper is the analyze of joining 3D printed polymer parts with adhesive. Furthermore, the aim of this research is to analyze the strength of lap adhesive joints under different loads. FDM technology, PLA materials and two-component epoxy adhesive were used to fabricate the testing specimens.
This paper aims to present the effects of the MIG welding on the mechanical properties of a buttwelded joint of dissimilar aluminium alloys 2024-T351 and AA 6082-T6. Aluminium alloy 6082 T6 is well weldable by classical fusion welding processes (MIG and TIG), while aluminium alloy 2024-T351 is almost non-weldable. For the welding of these two Al alloys, the MIG welding was used on an 8 mm thick sheet using filler material 4043A (AlSi5) and a mixture of argon and helium as a shielding gas. The influence of MIG welding on the obtained structure and mechanical properties of the welded joint was analyzed. The assessment of the mechanical properties of the welded joint of dissimilar Al alloys was performed by Vickers hardness testing, tensile and bending tests of the welded samples.
In this paper, the variability of morphological (stem height, stem basal diameter, proportion of pith, wood and bark) and wood anatomical characteristics (fiber length, fiber diameter, fiber lumen diamater, double cell-wall thickness, vessel diameter, wood rays width and height) of three Salix alba clones (B-44, 347 and NS 73/6) and one Salix viminalis clone both in the control plot and in the site contaminated with a mixture of heavy metals (As, Cd, Cr, Cu, Ni, Pb) was investigated. The observed results showed that individuals of all four clones had significantly higher average values of stem height and stem basal diameter at the control plot compared to the polluted site. As for the proportion of pith, bark and wood, heavy metals caused an increase in the share of pith and a decrease in the share of bark and wood in all clones with the exception of clone NS 73/6. The analysis of wood fiber dimensions showed that the values of all parameters were higher at the control site with the exception of fiber lumen diameter where higher values were observed for clones B-44 and NS 73/6 at the polluted site. Higher values of vessel diameter were recorded for all clones at the control plot, while wood rays width of all individuals was greater at the contaminated site. Regarding the wood rays height, only Salix viminalis showed higher value at the polluted site. These results confirmed that pollution-induced heavy metal stress significantly altered the morphological and wood anatomical characteristics of all researched clones and that it may affect their utility properties.
We study the significance of the common trusted relay assumption in quantum networks. While most practical implementations of quantum networks rely on trusted devices, the question of security without this assumption has been rarely addressed. Device independent security attempts to minimize the assumptions made on the quantum hardware, entanglement based methods try to avoid relays to the extent possible, and multipath transmission improves robustness and security by enforcing the attacker to conquer more than just a single intermediate node. Common to all these past studies is their focus on the physical layer and direct connections. We describe an attack from the networking and routing layer. Assuming at least one node that is not perfectly tamper-proof, meaning that an attacker has established a foothold to read traffic from the inside, we show how to exploit the eavesdropping detection mechanisms of the quantum key distribution (QKD) devices to cause traffic redirection over the vulnerable node, thus defeating security under the trusted node assumption. We experimentally demonstrate how the attack works on networks of different size and topology, and thereby further substantiate the significance of the trust assumptions for end-to-end security of QKD networks.
The application of conventional electric arc welding in argon protection (TIG welding process) has limited possibilities. These limitations are primarily related to the thickness of the welded material and the need to prepare the groove for their welding. Overcoming these limitations in TIG welding was done by using activating flux, so the procedure was named ATIG (A-TIG) welding. The paper presents the results of research into the application of activating fluxes in welding austenitic stainless steel 316L with a thickness of 6 mm. By using the BC-31 and QuickTIG melters of different chemical bases, we compare the mechanical properties of the welded joints, as well as with the welded joints of the same material obtained using the conventional TIG procedure. The results show that the best mechanical properties are possessed by welded joints realized by the ATIG process using a mixture of activating fluxes BC - 31 (50%) and QuickTIG (50%) (green + white flux).
With its nominal GDP USD 177.3 billion in 2022, the Hungarian economy is roughly equivalent to the economies of Serbia, Croatia and Slovenia, combined. Yet, these three countries are among the five most important Bosnia and Herzegovina's (B&H) trading partners in exports and imports, while Hungary only ranks eighth among B&H's most significant trading partners. By applying the gravity model, it was found that the basic gravity model (which takes into account only the size of the economy and the distance) is insufficient to explain the volume of trade between Bosnia and Herzegovina and Hungary. Actually, the fact that Bosnia and Herzegovina was once a member state of the Former Yugoslavia still has a significant impact on explaining the international trade of Bosnia and Herzegovina, simultaneously indicating the importance of historical, cultural, and political ties between the countries. The results obtained in this research study pertaining to the ten most significant trading partners of Bosnia and Herzegovina also suggest that the distance between the major cities more strongly influences exports than imports. Taking into consideration the size of the Hungarian economy and the distance, these results suggest that the trade volume between Bosnia and Herzegovina and Hungary is far below the expected level.
The application of circular economy principles in water supply systems has been increasingly studied recently. Concrete experiments and practical implementations in the industry are being carried out with the aim of cost savings, energy production, and material and energy recovery from wastewater treatment processes. In this context, the aim of this paper is to identify some measures that water utilities can take to enhance sustainability and reduce environmental impact. The paper provides a brief overview of the opportunities for water utilities to act on water, materials, and energy.
The analyzes carried out in this research were performed on meadow and mountain honey samples from Bosnia and Herzegovina. The geographical origin of the analyzed honey samples is the area of Mount Majevica in the Tuzla Canton and the area of Livno, Canton 10, Sarajevo, Sarajevo Canton and Vlašić, Central Bosnia Canton. Honey samples were collected from 8 different localities. During the analysis, all honey samples were up to one year old. With the aim of testing the antioxidant capacity of honey, the polyphenol content and total antioxidant capacity were determined. The total antioxidant capacity of honey was determined by the indirect FRAP (Ferric Reducing Antioxidant Power) method, and the polyphenol content by the Folin-Ciocalteu method. The results showed that there is a significant correlation between the antioxidant capacity of the analyzed honey samples and the content of polyphenols in them. In order to compare the antioxidant activity and polyphenol content of pure honey samples (without additives) with honey mixtures (additions: ginger, garlic, sweet wormwood, propolis), mixtures were prepared for all samples, namely 5 mixtures of honey and ginger; 5 mixtures of honey and garlic, 5 mixtures of honey and sweet wormwood and 3 mixtures of honey and propolis. Analyzing the results, a comparative analysis of the polyphenol content and total antioxidant capacity in honey samples before and after the addition of wormwood, ginger, garlic and propolis was performed, and the influence of the mixture's standing time on the tested parameters was also examined. The results of these analyzes showed that additives to honey significantly affect its antioxidant activity and polyphenol content, and that standing the prepared mixtures can lead to an additional increase or decrease of the tested parameters.
Adhesive bonding is a well-established technique for joining materials. This article deals with the challenges of bonding metals, such as aluminium alloy EN AW-5754. To improve the strength of bonded joints, suitable surface preparation prior to bonding is essential. In this work, the surface of the aluminium alloy using three different epoxy adhesives was subjected to two different methods of surface preparation, such as laser cleaning and sanding by hand with sandpaper. The adhesion properties of the bonded surface were determined by measuring the surface roughness parameters (Ra and Rz) for different surface preparations as well as the mechanical property (tensile lap-shear strength). It was found that the bond strength of the aluminium alloy changed depending on the surface preparation and adhesive used, indicating that using the same adhesive and material with different preparation methods can lead to significant variations in bond strength. Therefore, choosing an appropriate surface preparation method that is suitable for the parts to be bonded and their surface roughness is crucial as it increases the strength of the bonded joints.
Background: The organizational climate is defined as the perception of events within the work environment (relationships, values, actions) among organization members that are psychologically meaningful. It also includes the influence of the surroundings on employee motivation and behavior. This concept is studied within the field of industrial and organizational psychology, particularly focusing on healthcare institutions. Objective: The study aims to explain the concept, definition, and history of organizational climate, with a specific focus on healthcare institutions. It also aims to examine the factors influencing the work environment and the extent to which they can improve it. Methods: The research utilizes both quantitative and qualitative methods. The quantitative approach is presented through a non-standardized survey method. Qualitative research was conducted using case studies of healthcare institutions in Sarajevo Canton. The integration of these methods allowed for a comprehensive examination of the organizational climate. Results: The survey provided detailed insights into the organizational climate within healthcare institutions in Sarajevo Canton. It identified key factors that influence the work environment and highlighted areas for potential improvement. Discussion: The findings underscore the importance of strategic management of human resources and potential in creating a positive organizational climate. The study suggests that improving organizational climate is a long-term, multi-layered process involving doctors, managers, and all organizational members working towards common goals. Further research is needed to explore specific interventions that can enhance organizational climate in healthcare settings. Conclusion: This underscores the need for healthcare institutions to focus on fostering a supportive organizational climate and nurturing positive interpersonal interactions to enhance overall job satisfaction among employees.
In this study, the selection of suppliers within an alternative food supply network for fruits and vegetables, specifically Box Schemes, was conducted using multi-criteria decision-making methods. The Entropy-MABAC method was used as the multi-criteria decision-making approach, and the research focused on five suppliers from the city of Novi Sad. Eleven socioeconomic criteria were chosen for the research to identify the most favourable supplier. The results indicate that the criterion "product character," i.e., whether the final agricultural product is organic or conventional, was rated the highest, and the first supplier was selected as the most favourable. These results provide a solid foundation for future research, which should focus on further examining the impact of supply methods on end consumers of agricultural products within the alternative food network and developing new methods to aid in selecting the most favourable supplier.
Nema pronađenih rezultata, molimo da izmjenite uslove pretrage i pokušate ponovo!
Ova stranica koristi kolačiće da bi vam pružila najbolje iskustvo
Saznaj više