82129 research outputs found
Sort by
Quantitative investment analysis and portfolio management: an optimization perspective
Full text linkUsing mathematical models for maximizing returns and minimizing risk, this paper explores the process of dynamic portfolio optimization in the Republic of Serbia. The main focus is on the application of quantitative methods, including Markowitz’s model and the fundamental principles of portfolio theory, adapted to real market data. Through a practical example of a portfolio consisting of domestic company stocks and government bonds, it is demonstrated how investors can make rational decisions under changing market conditions. The paper emphasizes the importance of a dynamic approach, where the portfolio is periodically adjusted based on shifts in the market and economic environment. Furthermore, the presented results highlight the significance of diversification and quantitative risk control for investors in small open markets. The use of real data from the Belgrade Stock Exchange and the inclusion of government bonds in the analysis provide a specific contribution to the study. The obtained findings can serve as a foundation for investment decision-making and the improvement of portfolio strategies in the contemporary business conditions
Sequential extracellular organic matter-treatment boosts bioremediation efficiency : [abstract]
Full text linkA note on the stability of periodic orbits of planar Lotka-Volterra systems
Full text linkIn this paper we revisit previous results in the literature dealing with the stability of periodic solutions of periodic predator–prey Lotka–Volterra systems. These results provide stability criteria for the periodic orbits based on boundaries for the average of the coexistence states. In the way it was presented, these boundaries are independent of each other and thus provide a very practical sufficient condition for asymptotic stability. In this note we prove that this independent boundaries can be refined into an intertwined boundary, providing a more sharp sufficient condition
A bifurcation analysis on a nonlocal overdetermined problem
Full text linkIn this paper, we study an overdetermined problem with Kirchhoff type nonlocal terms related to the celebrated work by Serrin. We obtain the precise number of solutions according to the value of the bifurcation parameter and study asymptotics of bifurcation curves of solutions when the bifurcation parameter is large in some cases
A systematic method for complete stability problem of a class of delayed neural networks in parameter space
Full text linkThis paper presents a systematic method to address the complete stability problem of delayed neural networks with heterogeneous free parameters. First, we adopt an algebraic method to investigate the complete stability problem with respect to the free delay parameter τ. Then, the stability analysis is extended to the scenario with additional free system parameters, denoted by a vector X. We can investigate the complete root classification for the auxiliary characteristic equation in the entire (X, τ)- space. As a result, we can analytically calculate the number of stability τ-intervals and characterize all classifications of stability property over the whole (X, τ)-space. Finally, we will give a systematic method for determining the stability set in the whole (X, τ)- space. Some representative examples show the effectiveness of the approach
A Schweidel József-szobor sorsa a két világháború között
Full text linkThe monuments in the territories annexed by the Treaty of Trianon are often referred to as having been destroyed by the invading Serb/Romanian/Czechs. This is also the case with the Schweidel statue in Zombor, erected in 1905, and the statue of Ferenc Rákóczi II. According to my research, these were removed overnight in January 1920. In the early 1920s, these monuments were located in the yard of the Zombor fire barracks. It was Dr. Lőrinc Fehér, a lawyer from Baja, former mayor of Zombor, who first took the initiative to acquire the statues. The City of Baja, with the help of Dr. György Nikolics, a lawyer from Zombor, made several attempts to purchase the statues. The county of Bács-Bodrog also attempted to acquire the statues. In my paper, I will present these attempts on the basis of the documents of the Baja archives and the contemporary press. Jenő Borsay, the first director of the Baja museum, collected the documents concerning the acquisition of the statues. Jenő Borsay discovered that József Schweidel’s father was buried in Baja. He tried to build up a Schweidel cult in Baja. An interesting chapter in the shared history of the two Bácska towns in the years following 1921 can be seen. The memory of Schweidel’s statue continues to live on in the memory of the people of Zombor, thanks to literature and especially to János Herceg. According to the information that has been discovered, the statues were melted after 1931
