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In this article, we study the application of NetworkX, a Python library for dealing with traffic networks, to the problem of signal optimization at a single intersection. We use the shortest-path algorithms such as Bellman-Ford (Dynamic Programming), A star (A*), and Dijkstra’s algorithm to compute an optimal solution to the problem. We consider both undersaturated and oversaturated traffic conditions. The results show that we find optimal results with short Central Processor Unit (CPU) time using all the applied algorithms, where Dijkstra’s algorithm slightly outperformed others. Moreover, we show that bee colony optimization can find the optimal solution for all tested problems with different degrees of computational complexity for less CPU time, which is a new contribution to knowledge in this field.

The paper investigates the evolution of air passenger profiles in terms of regulatory environment, competitive landscape, socio-economic and demographic trends. The research is supported by passenger surveys carried out since 2001. The surveys have been designed to provide objective and in-depth insights into the preferences and behaviors of air passengers in the Serbian market. The resulting passenger segments are categorized based on socioeconomic and travel purpose criteria, but the surveys conducted at Serbian airports reveal that competition triggered the service quality to become a major issue in the Serbian market, after the entrance of low-cost carriers. The research of future projections of air passengers in Serbia is based on the Delphi method for two-time horizons (2025 and 2035) and three future scenarios are proposed.

The paper investigates the evolution of air passenger profiles in terms of regulatory environment, competitive landscape, socio-economic and demographic trends. The research is supported by passenger surveys carried out since 2001. The surveys have been designed to provide objective and in-depth insights into the preferences and behaviors of air passengers in the Serbian market. The resulting passenger segments are categorized based on socioeconomic and travel purpose criteria, but the surveys conducted at Serbian airports reveal that competition triggered the service quality to become a major issue in the Serbian market, after the entrance of low-cost carriers. The research of future projections of air passengers in Serbia is based on the Delphi method for two-time horizons (2025 and 2035) and three future scenarios are proposed. [ABSTRACT FROM AUTHOR]

The notion of discriminantly separable polynomials of degree two in each of three variables has been recently introduced and related to a class of integrable dynamical systems. Explicit integration of such systems can be performed in a way similar to Kowalevski’s original integration of the Kowalevski top. Here we present the role of discriminantly separable polynomials in integration of yet another well known integrable system, the so-called generalized Kowalevski top - the motion of a heavy rigid body about a fixed point in a double constant field. We present a novel way to obtain the separation variables for this system, based on the discriminantly separable polynomials. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 174020]

From the moment when the concept of the orthogonal set appeared in 2017, it become an interesting topic for research. Many authors investigated the uniqueness of best proximal point results in different types of metric space (X, d) where X is an orthogonal set and d is a metric on X. Investigation of those results goes in two main directions. The first type of investigation direction deals with different metric spaces, such as standard metric space, b-metric spaces, metric-like spaces, b metric-like spaces, modular spaces, etc. The second direction deals with different types of contraction. Firstly, we present some necessary definitions with many examples for a better understanding of the concept of the orthogonal set. After that, we give an overview of some results in this field and open problems that could be considered. [ABSTRACT FROM AUTHOR]

In the recent paper, authors have considered a problem of controlling an oversaturated intersection in real time and developed a mathematical model based on fuzzy logic. The model was tested on an oversaturate “T” intersection and we obtained solutions with less control delay in comparison to the “fixed time” model. First, we will present the basic concepts of those results. In the rest of the paper, we apply a similar technique to develop a model for controlling a diverging diamond interchange – a type of diamond interchange in which the two directions of traffic on the non-freeway road cross to the opposite side on both sides of the bridge at the freeway. This type of interchange was developed in the 1970s in France but since 2009. it has been implemented in many different locations, above all in the USA.

In this paper we study the equations of motion of a rigid body around a fixed point in the case of Kovalevskaya. We give interpretation of the 'mysterious substitution of variables' in Sofia Kovalevskaya's paper. The present paper also connects integration procedure proposed by Golubov with the original equations obtained by S. Kovalevskaya.

In this paper we consider a problem of controling an oversaturated intersection in real time. We developed a mathematical model for solving the problem, based on fuzzy logic. The model can be applied to intersections characterized by oversaturated traffic flows. We compared this fuzzy logic approach to the ”fixed time” controling of the oversaturated intersection. By ”fixed time” we understood controlling based on the hystorical data about traffic flows. In the case of the oversaturated intersection considered in this paper, a classical approach of controlling in real time (”actuated time control”) gives the same solutions as ”fixed time” control. The criterion function for comparing solutions represents the control delay of all vehicles that pass through the intersection within a certain period of analysis. We tested these approaches on a ”T” intersection, where the suggested model based on fuzzy logic generated solutions with less control delay in comparison to the ”fixed time” model. [ABSTRACT FROM AUTHOR]

We classify the discriminantly separable polynomials of degree two in each of three variables, defined by a property that all the discriminants as polynomials of two variables are factorized as products of two polynomials of one variable each. Our classification is based on the study of structures of zeros of a polynomial component P of a discriminant. This classification is related to the classification of pencils of conics in a delicate way. We establish a relationship between our classification and the classification of integrable quad-equations which has been suggested recently by Adler, Bobenko, and Suris. [ABSTRACT FROM AUTHOR]