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Jakob Axelsson, Damir Bilić, Daniel Brahneborg, Joakim Fröberg, Henrik Gustavsson, R. Jongeling, Daniel Sundmark

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.

Adriana Lipovac, Ante Mihaljević, V. Lipovac

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.

Miralem Mehic, Libor Michalek, Emir Dervisevic, Patrik Burdiak, Matej Plakalovic, J. Rozhon, Nerman Mahovac, Filip Richter et al.

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.

Šejla Cerić, E. Begić, B. Aziri, Nusret Salkica, Halil Čorović, selma Agić-Bilalagić, A. Begić

Two main types of cardiac amyloidosis (CA) exist, as a result of either aberrant plasma cell production of misfolded monoclonal light chains, known as immunoglobulin light chain amyloidosis (AL), or production of disintegrated and misfolded transthyretin (TTR) proteins by the liver, also called transthyretin amyloidosis (ATTR). Non-invasive diagnostics (cardiac uptake on diphosphonate scintigraphy, Perugini score 2 or 3) have gained prominence in modern cardiology in correlation with the negative findings of free light chains in serum and the results of negative immunofixation in serum and urine. Additionally, criteria related to echocardiography or cardiac magnetic resonance are necessary for establishing a diagnosis. A total of 3.063 99mTc-MDP bone scintigrams were analyzed between August 2018 and March 2023, of which Perugini score 1 was validated in 13 patients, Perugini score 2 in 10 patients and Perugini score 3 in 1 patient. From our experience, we could observe that cardiac uptake can be verified in daily clinical practice and that is meaningful for monitoring patients with ATTR-cardiomyopathy (ATTR-CM). Although the sample size is not large, the importance of the study lies in the fact that it involves patients whose findings have been incidentally verified. If patients are selected according to clinical characteristics, the number of positive findings may potentially increase. Our study aimes to raise awareness among physicians of various specialties about the significance of the diagnostic algorithm for infiltrative cardiomyopathies. This is to ensure early diagnosis of this problem and initiation of treatment in the earliest stages when the therapeutic effect is most optimal. Such an approach would yield benefits for both patients and the entire healthcare system. A meticulous diagnostic and therapeutic approach is therefore fundamental for improving clinical outcomes in patients with ATTR-CM, including careful attention to specific TTR genetic variants and long-term follow-up.

During vibrations, the structure passes through different behavior areas (elastic or inelastic). Different areas of behavior correspond to different approaches to analysis and design. Modeling vibrations as a phenomenon includes its presentation in the form of a mathematical model, with certain parameters specific to the system, which define and control the vibration process itself, namely mass, stiffness and damping. While mass and stiffness can be more accurately described mathematically, damping modeling involves the state and medium in which the system resides. Due to differences in understanding of the state variables that control damping forces, there is still no single accepted model of damping. The wrong selection of damping model in the dynamic analysis of structures can result in the response of the structure being underestimated, which can be the cause of the collapse of the structure. The paper analyzed the response of the bridge structure to pedestrian excitation, applying different numerical damping models and the damping determined experimentally. At the end of the paper, a comparative analysis with conclusions is given.

Ajla Bukva, Haris Memisevic

Fine motor skills are a good indicator of a child’s overall development. They underpin almost all everyday activities from self-care skills such as dressing to academic skills such as writing and drawing. In this study we examined the development of fine motor skills of early elementary school children. The sample for this study consisted of 175 children (93 boys, 82 girls, mean age= 120 months; SD = 10.7 months). attending 3rd, 4th, and 5th grades. We used Grooved Pegboard test for measuring fine motor skills. We found a medium, statistically significant, correlation between age and motor skills, with stronger correlation at younger age. In relation to child’s grade, there were statistically significant differences in motor skills between children attending 3rd and 4th grade, but no differences between children in 4th and 5th grade. As for the gender, there were no mean differences between boys and girls in the 3rd grade, but there were differences in 4th and 5th grade with girls achieving statistically significantly better scores on Grooved Pegboard test. Fine motor skills should routinely be examined in children and appropriate remediation programs should be set if a child falls behind in motor skills. We concluded a paper with several ways how elementary schools can include fine motor exercises in their curricula.

Mersiha Fazlic, Selma Poparic, Nina Čamdžić, Suada Vlahovljak, M. Babić, E. Halilović

Background: Basal cell carcinoma (BCC) is the most common nonmelanoma skin cancer. Although there has been a noticeable increase in incidence over the last decades, the exact incidence is difficult to establish, because data and cancer registries are heterogeneous among countries. Objective: The study aimed to analyze the recent clinical trends of basal cell carcinoma by reviewing a six-year single institution’s experience. Methods: A total number of 582 patients with histologically diagnosed BCC were included in the study. All relevant data were collected from medical records and patients, using short questionnaire. Results: BCC was slightly more common among the male population with female to male ratio of 1:1.24. At the time of diagnosis, male patients were statistically significantly older (70.47±11.9 years) compared to female patients (67.64±12.22 years) (p=0.005). The most common types of BCC were nodular (51.64%) and superficial (25.95%), affecting most commonly the head and neck region (71.2%). Relative risk (RR) for development of BCC is 2.79 times higher in sun-exposed skin areas (p<0.001). Conclusion: Sun exposure remains one of the most important risk factors for the development of BCC, with episodes of sunburns, occupational and recreational risks noted among the majority of patients. Although non-fatal disease, due to morbidity and high frequency, prevention and early diagnosis are important to prevent further increase in the incidence of BCC among the population.

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