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.

Physical inactivity, unhealthy diet, fast-paced lifestyle, as well as genetic predispositions lead to the appearance of diabetes mellitus, and with it many other complications, of which diabetic foot syndrome is very common. In order to avoid complications with the diabetic foot, one of the forms of prevention is wearing specially designed footwear that protects and reduces the pressure on the foot and thus the risk of ulcers. Insoles also play a big role in preventing complications. The paper will present a conceptual solution of a model of footwear for patients with diabetes mellitus and a prototype of an insole made of knitwear, which was previously printed with medical clay, honey and extracts of the plants Rosmarinus officinalis and Zingiber officinale. Samples of knitwear that were printed with a paste containing Rosmarinus officinalis extract showed exceptional antimicrobial activity against Staphylococcus aureus bacteria. Replaceable insoles for footwear are intended for the prevention of complications from Diabetes mellitus.

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.

This article describes the architecture life cycle effect analysis (ALCEA) method, a structured method for evaluating proposed new architectures for software-intensive systems. The method evaluates a proposed architecture by quantifying its effect on the performance of system life-cycle phases. The method is instantiated by identifying the relevant life-cycle phases of the system under investigation and a set of evaluation functions that capture, in terms of basic factors, the effect of different architectural decisions on key life-cycle PAs, such as revenue, operating resources, and investments. The method results in a transparent cost and revenue structure, documented in a tabular form, based on quantifiable factors from the developing organization. The results of the method can be used directly as part of a business case, and their robustness can be estimated by sensitivity analysis. The ALCEA method is designed for system-level architectural analysis, covering both software and hardware aspects. In this article, we introduce the ALCEA method and provide a detailed example of how to apply it in the evolution of embedded systems. Moreover, we share early experiences of using the method in large-scale industrial settings.

Large peak-to-average power ratio (PAPR) and carrier frequency offset (CFO) are dominant impairments of the orthogonal frequency-division multiplexing (OFDM) symbol transmission that is applied within the state-of-the-art wireless operator networks. In this work, we deal with consequences of the amplitude peak clipping that is commonly used at the transmitter to reduce the PAPR of the OFDM symbol, and thus prevent its non-linear distortion which would otherwise be imposed by the output high-power amplifier (HPA). Accordingly, regardless of the clipping generating mechanism at the transmitter being either inherent (related to the HPA) or deliberate (due to PAPR reduction), the clipped incoming OFDM symbol at the receiver may lead to degraded detection accuracy and transmission performance. However, the methods that have been applied so far at the receiver for compensating non-linear distortion due to clipping, are quite complex and computationally demanding. On the contrary, we propose effective mitigation of the problem to be performed at the receiver, by deriving the closed-form enhanced detection criterion, which requires common measurements of the mean and the rms values, as well as the autocorrelation of the received OFDM symbol comprising both un-clipped and clipped sections. Such improved detection was shown to significantly reduce the side effects of clipping, and restore satisfactory transmission performance – the bit error rate (BER) in particular. The proposed analytical model was preliminarily verified by versatile Monte-Carlo simulations and professional industry-standard vector signal analysis (VSA) test system, as well as by BER testing. The evident convergence of the three methods’ test results leads to the conclusion that the proposed clipped OFDM symbol detection method provides clear improvement with respect to the conventional one.

Every attempt to access to the Internet through a Web browser, email sent, VPN connection, VoIP call, instant message or other use of telecommunications systems involves cryptographic techniques. The most commonly applied technique is asymmetric cryptography, which is generally executed in the background without the user even being aware. It establishes a cryptographic code based on the computational complexity of mathematical problems. However, this type of cryptography, which is widely used in today’s telecommunications systems, is under threat as electronics and computing rapidly develop. The development of fifth-generation cellular networks (5G) is gaining momentum, and given its wide field of application, security requires special attention. This is especially true faced with the development of quantum computers. One solution to this security challenge is to use more advanced techniques to establish cryptographic keys that are not susceptible to attack. An essential part of quantum cryptography, Quantum Key Distribution (QKD) uses the principles of quantum physics to establish and distribute symmetric cryptographic keys between two geographically distant users. QKD establishes information-theoretically secure cryptographic keys that are resistant to eavesdropping when they are created. In this paper, we survey the security challenges and approaches in 5G networks concerning network protocols, interfaces and management organizations. We begin by examining the fundamentals of QKD and discuss the creation of QKD networks and their applications. We then outline QKD network architecture and its components and standards, following with a summary of QKD and post-quantum key distribution techniques and approaches for its integration into existing security frameworks such as VPNs (IPsec and MACsec). We also discuss the requirements, architecture and methods for implementing the FPGA-based encryptors needed to execute cryptographic algorithms with security keys. We discuss the performance and technologies of post-quantum cryptography, and finally, examine reported 5G demonstrations which have used quantum technologies, highlighting future research directions.

The optical time-domain reflectometer (OTDR) is a primary test and measurement instrument for detecting, localizing, and qualifying various fiber optic link events induced by breaks, splices, and connectors. However, in spite of a number of innovative enhancements of the OTDR capabilities proposed throughout decades of its use in the communications test application area, few reports can be found about extending the OTDR capabilities beyond detecting and qualifying refractive and reflective events of the fiber under test, to also include prediction of performance and impairments specifically related to the coherent optical orthogonal frequency-division multiplexing (CO-OFDM) symbol transmission over fiber link. As large enough OTDR dynamic range (DR) provides alike optical signal-to-noise-ratio (OSNR) even at the far end of the fiber, then the dominantly reflective OTDR trace pattern can be considered as the two-way power-delay profile (PDP) of the fiber. Furthermore, in this work, we also justifiably assume that the cyclic prefix (CP) is applied to guard the OFDM symbol against inter-symbol interference, as well as that the (formerly eventually large) peak-to-average power ratio (PAPR) is significantly reduced, e.g., by simple peak clipping at the transmitter. This finally retains the OFDM carrier frequency offset (CFO) as the major OFDM-inherent signal impairment to dominantly determine the bit error rate (BER) floor in this case. Accordingly, in our model, we abstracted the CFO by the additional delays added to the original OTDR trace pulses, which would produce an equal BER increase as the CFO does with the original trace. Inversely, this enables indirect estimation of CFO by simple BER testing, rather than by using dedicated and complex test instrumentation such as vector signal analyzer (VSA), not always at hand in field conditions.

This paper proposes an ac fault ride-through (FRT) method for high-voltage dc (HVDC) transmission systems that serve as an interconnector between the onshore ac grid and an islanded offshore ac grid. In conventional HVDC systems for offshore wind farms FRT is realized by consuming excess power with braking resistors. However, the same method cannot be applied if the offshore ac grid includes not only wind farms but also various loads, which are being considered for integration into multipurpose interconnectors or energy islands. In this article, a novel FRT method based on voltage control for HVDC interconnectors operating with bidirectional power flow is proposed. The proposed method curtails the ac voltage formed by the offshore converter according to the converter’s dc current and voltage. The effectiveness of the proposed FRT method is established through experiments on a mini model.

Background: Thyroid dysfunction includes hyper- and hypofunction of the thyroid gland (hyperthyroidism and hypothyroidism). The spectrum encompasses both subclinical and clinical disease presentation. The etiology is vast and varied, as are the risk factors and simptoms. Objective: The main aim of the research is to indicate the leading symptom for initial thyroid hormone status evaluation, as well as to identify the distribution of positive and negative test results, and specific disorders according to sex and age groups. Methods: The research is designed as a retrospective, clinical, descriptive study. There were 500 participants included, 355 female and 145 male. Patients were referred to the Department of endocrinology by their primary care physicians. The data was collected through patient documentation. Results: The study included 500 participants, 71% of diagnostic requests made were for women. 80% of subjects had normal thyroid hormone status, p<0.001. Most requests were made for the 41-60 age group, p<0.001. Women had similar number of positive and negative test outcomes, as well as men. When it comes to the age groups, outcomes were similar in all of them, 15-23% positive and 77-85% negative. There were significant differences in the type of symptom expressed in both men and women, as well as all the age groups. Men reported high blood pressure as the most common symptom (30.3%), while women reported weight gain (22.3%). In the 18-25 and 26-40 age groups most common symptom belongs to the category of other. Age group of 41-60 reported weight gain as the most common symptom, while in participants older than 60, high blood pressure is proven to be the most common. Hypothyroidism is the most common disorder in both men and women, as well as in all age groups. Conclusion: It is statistically proven that there were more requests made for women, and older age groups. Leading symptom for initial thyroid hormone status evaluation is high blood pressure. There is no statistically significant difference in distribution of thyroid disorders according to sex or age groups.

Consumption of fish has increased in last 50 years. Fish as a food is changing red meat because it has unsaturated fat and it is the best source of omega 3 fatty acids. Beside it is full of minerals, vitamins and it has high biological value of proteins.The content of heavy metals in the muscle tissue of fish is directly related to the pollution of the water they come from The analysis of the content of heavy metals was done by the Institute of Public Health of the Federation of Bosnia and Herzegovina.The content of lead (Pb) in the tested samples of fresh fish ranged from 0.0015 to 0.0381 mg/kg. The measured content of cadmium (Cd) in the examined samples was in the range of 3.3*10-5 to 0.0053 mg/kg. The content of arsenic (As) in the tested samples ranged from 0.0085 to 1.1668 mg/kg. The mercury (Hg) content in the tested samples of fresh fish ranged from 0.0033 to 0.0991 mg/kg, which is within the allowed values prescribed by the Rulebook. It has been statistically proven that there is a significant difference in the measured values of lead, arsenic and cadmium in the samples of sea and freshwater fish. Aim of this work was to establish do the samples of fresh fish contain concentration of heavy metals more than concentrations prescribed in Rule book about allowed amounts of certain contaminants in food. Thereby ten samples of fresh fish were tested, five samples of marine fish and five samples of freshwater fish. Results showed that all samples of fish satisfy allowed concentration of heavy metals according to the Rule book.

The concept of usufruct as an independent right, ius in re aliena, was not questioned in Justinian’s sources, while on the other hand, its systematisation, development, and legal nature in analyses of classical law were the subject of serious debates among Romance experts, mainly in Italian Romance studies from the beginning of the 20th century. Some experts in Romance studies understood usufruct as pars dominii, i.e. part of the property right that the owner retains for himself, thereby denying him the position of a special right. Such a concept originates from the glossator and post-glossator schools and, the paper analyses strong reflections of their teaching on contemporary legal doctrine. The paper deals with the concept and definition of usufruct and conducts analysis into the legal sources and reasons that led to differences in the understanding of the legal nature of the institute in the Roman legal tradition.

We use the Kolmogorov-Arnold-Moser (KAM) theory to investigate the stability of solutions of a system of difference equations, a certain class of a generalized May's host-parasitoid model. We show the existence of the extinction, interior, and boundary equilibrium points and examine their stability. When the rate of increase of hosts is less than one, the zero equilibrium is globally asymptotically stable, which means that both populations are extinct. We thoroughly describe the dynamics of 1:1 non-isolated resonance fixed points and have used the KAM theory to determine the stability of interior equilibrium point. Also, we have conducted several numerical simulations to support our findings by using the software package Mathematica.