A QKD network provides an additional security layer for IT-secure cryptographic key distribution that is added to existing conventional networks. Thus, QKD network components must be resilient to security challenges from conventional network environments. This paper provided a novel solution for designing a Key Management System resistant to DoS attacks. Our solution allows applications to function securely in environments with fewer keys. In addition, we have provided approaches for allocating and managing QKD resources to avoid malicious key reservations. Simulation experiments verified the proposed solutions.

In GMAW welding, there are several types of metal transfer that are primarily determined by the primary welding parameters. Different metal transfers in an electric arc are characteristic of different applications. In this paper, a detailed characterization of the pulse transfer of metals in an electric arc is performed, including the characterization of parameters and criteria for their selection on the used power source for welding Welbee. For a given Welbee device, the choice of parameters in steel welding is shown, as well as the synergy function that is characteristic of these devices. Welding was performed on structural steels, with previously adopted parameters, accompanied by recording the dynamic characteristics of current and voltage with an oscilloscope. Based on the available literature sources, the existing models for heat input calculation in GMAW pulse welding were analysed in detail. Heat input calculation for welded steel sheets was performed by using one of them, with current and voltage profiles recorded with an oscilloscope. After the experiment, the obtained results were elaborated, and general comments were given regarding influence of parameters on the quality of welded joints.

In this letter, we study the trade-off between exploration and exploitation for linear quadratic adaptive control. This trade-off can be expressed as a function of the exploration and exploitation costs, called cumulative regret. It has been shown over the years that the optimal asymptotic rate of the cumulative regret is in many instances $\mathcal {O}(\sqrt {T})$ . In particular, this rate can be obtained by adding a white noise external excitation, with a variance decaying as $\mathcal {O}(1/\sqrt {T})$ . As the amount of excitation is pre-determined, such approaches can be viewed as open loop control of the external excitation. In this contribution, we approach the problem of designing the external excitation from a feedback perspective leveraging the well known benefits of feedback control for decreasing sensitivity to external disturbances and system-model mismatch, as compared to open loop strategies. We base the feedback on the Fisher information matrix which is a measure of the accuracy of the model. Specifically, the amplitude of the exploration signal is seen as the control input while the minimum eigenvalue of the Fisher matrix is the variable to be controlled. We call such exploration strategies Fisher Feedback Exploration (F2E). We propose one explicit F2E design, called Inverse Fisher Feedback Exploration (IF2E), and argue that this design guarantees the optimal asymptotic rate for the cumulative regret. We provide theoretical support for IF2E and in a numerical example we illustrate benefits of IF2E and compare it with the open loop approach as well as a method based on Thompson sampling.

Bosnia and Herzegovina is a country with a very high risk of floods, which is documented in Vulnerability assessment, where it is defined that "floods represent the greatest danger for community and its population". Due to climate changes in recent decades, floods have become one of the most serious forms of threat to the population and material assets. After signing the Stabilization and Association Agreement with the EU in 2008, BiH accepted obligation to harmonize its legislation with the EU acquis communautaire, which also includes water legislation. The complex constitutional arrangement and unfavorable socio-economic situation make it difficult to fulfill assumed obligations, as well as protection and rescue system normal functioning on state territory. This research subject is protection and rescue system analysis, assessment of the adequacy of existing measures and current flood risk management techniques in BiH through a comparative analysis with practice of flood risk management in the EU.

Nowadays, when operating in an unstable market, organizations in Bosnia and Herzegovina (BiH) are also facing a continuous outflow of qualified employees to the countries of the European Union. In order to properly respond to the challenges from the environment, the organizations in BiH are forced to take adequate measures so as to become competitive in the market, which may prove to be difficult if they do not retain skilled workforce. This paper attempts to show that by implementing appropriate human resource management (HRM) practices and policies, organizations in BiH can affect employee organizational commitment, which will result not only in market survival but also in increased competitiveness, as the experience of the organizations in the surrounding countries shows that human resources is what gives these companies a competitive advantage. The paper aimed at examining the impact of characteristics, organizational characteristics, and HRM practices focused on performance appraisal, job security, employee participation, and career planning on employee organizational commitment in BiH companies with more than 50 employees in four sectors. The empirical research was conducted on a sample of 128 companies. The results show that when it comes to employee organizational commitment, HRM practices and policies bear more importance than demographic and organizational characteristics and that there is a statistically significant positive impact of HRM practices and policies on employee organizational commitment.