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We consider a multi-server queueing system with a visible queue and an arrival flow that is dynamically dependent on the system's rating. This rating reflects the level of customer satisfaction with the quality and price of the provided service. A higher rating implies a higher arrival rate, which motivates the service provider to increase the price of the service. A steady-state analysis of this system using the proposed mechanism for changing the rating and a threshold strategy for changing the price is performed. This is carried out via the consideration of a suitably constructed multidimensional Markov chain. The impact of the variation in the threshold defining the strategy for changing the price on the key performance indicators is numerically illustrated. The results can be used to make managerial decisions, leading to an increase in the effectiveness of system operations. [ABSTRACT FROM AUTHOR]

In this paper, we analyze a multi-server queueing system with a marked Markov arrival process of two types of customers and a phase-type distribution of service time depending on the type of customer. Customers of both types are assumed to be impatient and renege from the buffers after an exponentially distributed number of times. The strategy of flexible provisioning of priorities is analyzed. It assumes a randomized choice of the customers from the buffers, with probabilities dependent on the relation between the number of customers in a priority finite buffer and the fixed threshold value. To simplify the construction of the underlying Markov chain and the derivation of the explicit form of its generator, we use the so-called generalized phase-type distribution. It is shown that the created Markov chain fits the category of asymptotically quasi-Toeplitz Markov chains. Using this fact, we show that the considered Markov chain is ergodic for any value of the system parameters and compute its stationary distribution. Expressions for key performance measures are presented. Numerical results that show how the parameters of the control strategy affect the system's performance measurements are given. It is shown that the results can be used for managerial purposes and that it is crucial to take correlation in the arrival process into account. [ABSTRACT FROM AUTHOR]

Explores the state of the college student community in Moscow (Russia). Focuses on the changes in the social structure, the comparison of the material condition of college students and other social groups, and the problem of students' learning activity, in particular their value orientations and the quality of educational services. (CMK)

A problem of the optimal choice of the number of lanes and admission control in the road that is shared by the local and transit vehicles is considered. The operation of a road is modelled by the M M A P / M / 1 type queue with two types of customers. The service of type-2 (local) customers is mandatory. Type-1 (transit) customers can use alternative routes and, therefore, abandon or interrupt service in the considered system. All admitted customers are serviced simultaneously. A customer receives a constant part of a server bandwidth if the number of customers does not exceed a predefined in advance threshold and the reduced part, otherwise. The stability condition is derive and the stationary distribution of the system states is computed. A potential application for optimizing the number of lanes in the road is numerically illustrated. [ABSTRACT FROM AUTHOR]

A new type of tandem queueing systems with heterogeneous customers is analysed. Tandem consists of two stations each of which is modelled by a multi-server queueing system. Type-1 customers need service at station 1. After service at this station, a type-1 customer spends a random amount of time in the so-called pre-service area and then moves for service at station 2. Type-2 customers need service only at station 2 and have lower priority. A strategy of their admission depending on the current number of customers in the pre-service area and station 2 is offered. This strategy is defined by three integers (thresholds). Cost criterion, which defines the quality of the system operation, is the weighted sum of the mean numbers of lost customers from the pre-service area and type-2 customers per unit of time. The most difficult part of solving the problem of minimizing the cost criterion consists of computation of the stationary distribution of the system states under the fixed set of the thresholds. Numerical results are presented. Results can be used for optimization of various real-world systems such as manufacturing, transportation and health-care systems as well as for optimization of booking systems in HORECA (hotel/restaurant/cafe), museums, etc. [ABSTRACT FROM AUTHOR]

In the paper, optimal control problems with discontinuous right-hand side are considered. The main attention is paid to situations when there are intervals where optimal trajectory lies on a switching surface. It is shown that for such a situation the known optimality conditions degenerate: they are satisfied for any feasible control. Hence such conditions are not informative. New non-degenerate necessary optimality conditions in a form of Maximum principle are formulated and proved. Comparison of the obtained optimality conditions with ones known from the literature is presented. [ABSTRACT FROM AUTHOR]

Transnational corporations (TNCs) are one of the most important actors in both the international and national economies, particularly in the Russian Federation. This paper examines how socio-economic internationalization is realized by increasing the development of transnational corporations, the significance of the role played by transnational corporations in the current economic turmoil in the face of sanctions to ensure sustainable economic growth in the economy and boost global economic competitiveness. The challenge lies in figuring out the proper involvement of TNCs in the national environment, along with the possible risks and benefits for specific economies and other stakeholders. These initiatives should contribute to sustainable socio-economic development and a better quality of life in the current state of the Russian economy. Transnational corporations (TNCs) are one of the driving forces behind the internationalization of international production, the liberalization of international trade, and, ultimately, the development of the national economy. As the scientific and technological revolution progresses, TNCs are becoming one of the most important and dominant phenomena, respectively, and the subjects of the current fundamental economic processes.

A single-server queueing system with a marked Markovian arrival process of heterogeneous customers is considered. Type-1 customers have limited preemptive priority over type-2 customers. There is an infinite buffer for type-2 customers and no buffer for type-1 customers. There is also a finite buffer (stock) for consumable additional items (semi-products, half-stocks, etc.) which arrive according to the Markovian arrival process. Service of a customer requires a fixed number of consumable additional items depending on the type of the customer. The service time has a phase-type distribution depending on the type of the customer. Customers in the buffer are impatient and may leave the system without service after an exponentially distributed amount of waiting time. Aiming to minimize the loss probability of type-1 customers and maximize throughput of the system, a threshold strategy of admission to service of type-2 customers is offered. Service of type-2 customer can start only if the server is idle and the number of consumable additional items in the stock exceeds the fixed threshold. Stationary distributions of the system states and the waiting time are computed. In the numerical example, we show some interesting effects and illustrate a possibility of application of the presented results for solution of optimization problems.

Currently, the use of cash payments in the economy is an undesirable element since it is the basis for the shadow economy development. The willingness of the Russian Federation Government to switch to non-cash payments has reason. The implementation of many state programs depends on the non-cash payments development, especially in developing regions. Non-cash payments allow to take control of the movement of funds, as well as assess its origin. Moreover, they contribute to the growth of tax revenues to the budget. The purpose of the article is to analyze the payment system development of the Russian Federation, the development level of non-cash payments in the territory of the Russian Federation in the context of the regions, to identify the main reasons that impede the payment infrastructure development. Much attention is paid to the regions, since it is here that the entering of banking services leaves much to be desired. The goals set by the authors - to carry out a comparative analysis, horizontal and vertical analysis, to identify the main indicators of the level of «non-cash» settlements. Accordingly, build hypotheses and draw conclusions and recommendations. It is necessary to transfer as many transactions as possible to non-cash payments, and this depends on the interest of consumers in settlements with bank cards and other non-cash instruments.

A multi-server queueing system with two types of customers and an infinite buffer operating in a random environment as a model of a contact center is investigated. The arrival flow of customers is described by a marked Markovian arrival process. Type 1 customers have a non-preemptive priority over type 2 customers and can leave the buffer due to a lack of service. The service times of different type customers have a phase-type distribution with different parameters. To facilitate the investigation of the system we use a generalized phase-type service time distribution. The criterion of ergodicity for a multi-dimensional Markov chain describing the behavior of the system and the algorithm for computation of its steady-state distribution are outlined. Some key performance measures are calculated. The Laplace-Stieltjes transforms of the sojourn and waiting time distributions of priority and non-priority customers are derived. A numerical example illustrating the importance of taking into account the correlation in the arrival process is presented