Queueing System with Potential for Recruiting Secondary Servers

In this paper, we consider a single server queueing system in which the arrivals occur according to a Markovian arrival process (MAP). The served customers may be recruited (or opted from those customers’ point of view) to act as secondary servers to provide services to the waiting customers. Such customers who are recruited to be servers are referred to as secondary servers. The service times of the main as well as that of the secondary servers are assumed to be exponentially distributed possibly with different parameters. Assuming that at most there can only be one secondary server at any given time and that the secondary server will leave after serving its assigned group of customers, the model is studied as a QBD-type queue. However, one can also study this model as a G I/M/1-type queue. The model is analyzed in steady state, and a few illustrative numerical examples are presented

Analysis of Single-Server Queue with Phase-Type Service and Energy Harvesting

We propose a queueing model suitable, for example, for modelling operation of nodes of sensor networks. The sensor node senses a random field and generates packets to be transmitted to the central node. The sensor node has a battery of a finite capacity and harvests energy during its operation from outside (using solar cells, wind turbines, piezoelectric cells, etc.). We assume that, generally speaking, service (transmission) of a packet consists of a random number of phases and implementation of each phase requires a unit of energy. If the battery becomes empty, transmission is failed. To reduce the probability of forced transmission termination, we suggest that the packet can be accepted for transmission only when the number of energy units is greater than or equal to some threshold. Under quite general assumptions about the pattern of the arrival processes of packets and energy, we compute the stationary distributions of the system states and the waiting time of a packet in the system and numerically analyze performance measures of the system as functions of the threshold. Validity of Little’s formula and its counterpart is verified

Analysis of the “sustainable development” concept

The article presents the results of the study of the essence and specificity of the term "sustainable development", as well as the development of its author's vision in modern realities. Currently, sustainable development is one of the key trends in the development of the world. At the same time, it affects almost all aspects of society and the state. It is explained by the fact that it is based on three important areas: economic, environmental and social. However, there are both opponents and supporters of the concept of sustainable development. The greatest success in implementation in practice and scientific results have been achieved by researchers in developed foreign countries: Europe, USA, Japan, etc. At the same time, there is no unified position in the essence and peculiarities of such a complex interdisciplinary category. The purpose of this work was to develop an adequate approach to assessing the modern interpretation of the term "sustainable development". The study is based on the work of many domestic and foreign authors. The main method of work is analytical. The results obtained -a detailed analysis of the development of approaches to the studied terminology, allowed us to formulate the author's current approach to this concept

A model for improving the efficiency of forest industry enterprises in the context of rational environmental management

The development of the forest industry is one of the important goals of state policy. The purpose of the work was to study certain aspects of the efficiency of Russian forest industry enterprises in the context of rational environmental management and to develop a graphical model for its improvement. The main research methods are analytical, modeling, and statistical data processing. As a result, information was obtained on the current level of efficiency of production of forest industry key products by regions of the country. The development of the model was based on the general hypothesis of the study, that expanding the depth of wood biomass processing while reducing the negative impact on the environment leads to increased efficiency and sustainable development of enterprises in the forest industry. The proposed model demonstrates certain aspects of the interaction of forest industry enterprises with the environment. The most important elements of this model are waste-free production and the deep processing production, based, among other things, on the use of waste from the main production. To increase the efficiency of forest industry enterprises, it is extremely important to develop and implement environmental management measures

Thermal calculations of underground oil pipelines

Operation of oil pipelines in the frozen soil causes heat exchange between the pipeline and the soil and formation of a melt zone which leads to deformation of pipelines. Terms of construction and operation of oil pipelines are greatly related to their temperature conditions. In this regard it is necessary to know the laws of formation of thawing halos around oil pipelines. Thus, elucidation of laws of formation of thawing halos around oil pipelines and determination of optimal conditions for their installation during construction in areas of permafrost in the north of Tyumen region is a very urgent task. The authors developed an algorithm and a computer program for construction of the temperature field of the frozen soil. Some problems have been solved basing on the obtained dependences and graphs of the dependence were constructed. Research and calculations made on the underground oil pipeline construction allowed the authors to give recommendations aimed at increasing the reliability of oil pipelines

SCINTILLATION SPECTROMETER SBL-1 FOR THE X-RAY DENSITOMETER OF RADIOACTIVE TECHNOLOGICAL SOLUTIONS

Results of property study of the developed high-acting scintillation spectrometer to be used in x-ray densitometer of radioactive solutions with 241Am "transmitting" radiant are presented. Fast crystals YAlO3:Ce (Æ25x0.4 and Æ25x1.0 mm) are used as scintillators. Strong energy resolution dependence of the spectrometer with thin scintillators at crystal illumination (from 16.3 to 20.3 % for a g-line 59.5 keV) is revealed. The spectrometer input count-rate is over 5·105 1/s, and spectrum accumulation speed is not lower than 2·105 1/s. Due to the conversion gain program stabilization the relative shift and the peak broadening Eγ = 59.5 keV do not exceed 0.25 % and 7.5 %, accordingly.Keywords: YAlO3:Ce, x-ray scintillation spectrometer, thin crystal, 241Am, radioactive solutions, program stabilization, high count-rate, energy resolution.DOI: http://dx.doi.org/10.15826/analitika.2013.17.1.003 M.P. Belousov1, M.A. Gorbunov2, S.V. Dudin1, O.V. Ignatyev1,S.G. Morozov2, A.A. Pulin2 1Ural Federal University named after the first President of Russia B.N. Yeltsin, Ekaterinburg, Russian Federation2 ATOM Electronics Ltd, Ekaterinburg, Russian Federation Results of property study of the developed high-acting scintillation spectrometer to be used in x-ray densitometer of radioactive solutions with 241Am "transmitting" radiant are presented. Fast crystals YAlO3:Ce (Æ25x0.4 and Æ25x1.0 mm) are used as scintillators. Strong energy resolution dependence of the spectrometer with thin scintillators at crystal illumination (from 16.3 to 20.3 % for a g-line 59.5 keV) is revealed. The spectrometer input count-rate is over 5·105 1/s, and spectrum accumulation speed is not lower than 2·105 1/s. Due to the conversion gain program stabilization the relative shift and the peak broadening Eγ = 59.5 keV do not exceed 0.25 % and 7.5 %, accordingly.Keywords: YAlO3:Ce, x-ray scintillation spectrometer, thin crystal, 241Am, radioactive solutions, program stabilization, high count-rate, energy resolution.DOI: http://dx.doi.org/10.15826/analitika.2013.17.1.00

Provision of Global Economic and Energy Security in the Context of the Development of the Arctic Resource Base by Industrialized Countries

Some issues related to the problems of development of the Arctic and subarctic areas, which according to various expert estimates contain between 15% and 25% of the world reserves of primary energy resources, are presented and disclosed in this article. The purpose of this article is to develop a system of global economic and energy security provision in the context of advanced deposits developments in the Arctic. The goals set were consistently achieved, in particular: the general trends of the energy development of civilization were examined, the legal issues concerning the status of the subarctic and Arctic regions were considered, and the basic global trends of world energy development and the system of global energy security provision were defined. The following fundamental findings were obtained: Firstly, the subarctic and Arctic areas represent world heritage, so the development of deposits therein should be in the interests of the world community on a non-discriminatory basis. Secondly, civilization's future energy supplies will be based on the harmony of traditional and renewable energy sources, which determines the need to rationalize the consumption of energy resources at present. Thirdly, the environmental issues of prospective development of the Arctic and subarctic areas are sufficiently acute and debatable that non-aggressive technologies of primary energy resource extraction from the Arctic fields should be used. Significant reserves of hydrocarbon resources in the Arctic shelf allow estimation of a significant global rental potential, despite the territorial remoteness and difficult climatic conditions that greatly increase the cost of development in these areas. Therefore, the planning and management of the Arctic and subarctic areas should be considered as a strategic reserve of sustainable global socio-economic development. Keywords: Energy Security; arctic; industrialized countries; economic security; resources JEL Classifications: Q41; Q47; Q5

Financial Crisis in Greece: Challenges and Threats for the Global Economy

This article is devoted to the research of the reasons behind the occurrence of the crisis in Greece and challenges and opportunities that arise both for the global economy and the economy of the European Union (EU). The theme of the article is rather urgent by reason of incomplete understanding of the nature of the crisis in Greece, its suddenness and impossibility to predict its consequences for the global economic relations. The main goal of stating the materials in this article is to analyze the reasons of the crisis in Greece in terms of economy, history, sociology, and other scientific areas. Basic tasks include the following: To reveal a complex of all aspects of the economic crisis in Greece, to analyze its deep (historical) reasons, and to reveal challenges for the world economy and economy of the EU and Russia related to the Greek crisis. The flowing basic conclusions were made within the article: (1) The crisis in Greece has not only economic but also political reasons. However, at the same time the Greek crisis cannot be solved only in terms of economy. It is necessary to take systematic measures to solve the occurred problems, (2) the economic crisis is only a visible part of structural problems of the Greek economy. At the present time a great number of social, technological, and humanitarian problems have been hidden behind the mass revealing of economic crisis tendencies, (3) the basic reason of the economic crisis is in the incompliance of social and economic model of the Greece development with the EU based on the West-European logics of functioning. Practical application of the results of this work by scientists and economists will allow to objectively reconsider the essence of the Greek crisis, and make conclusions that will contribute to the development of recommendations aiming at preventing the crisis in other countries. Keywords: Greece, Economic Crisis, European Union, Global Economy JEL Classifications: G01, N24, F6

ВЛИЯНИЕ ВНЕШНЕСРЕДОВЫХ АСПЕКТОВ НА ПОВЫШЕНИЕ ИННОВАЦИОННОЙ АКТИВНОСТИ ЛОГИСТИЧЕСКИХ ОПЕРАТОРОВ ХОЗЯЙСТВУЮЩИХ СУБЪЕКТОВ

This article aims to consideration of exogenous aspects that affect the innovation activity of logistic operators and determine the main directions of innovation in the logistics market. The presentation materials on the subject of the article allows to generate the following key findings obtained in the course of the work: the global logistics market is actively developed and is currently undergoing a phase of high-quality update that is associated with a change in the role of logistics operators in the provision of services to its customers (the transition from the hierarchical form of interaction to an affiliate); with the organizational and economic point of view, the global logistics market is formed by two key segments (b-2-b business-to-business and b-2-c business-to-customer), within which operate three key types of logistics operators; Innovation in the field of logistics is considered as a key factor in the creation of high value-added logistics services, and as a basis for the formation of these high-value services to customers; a set of innovations designed to improve the value-added logistics services and their value to the customer, must be considered both in terms of the organization managing the logistics fl ow and in terms of the physical organization of the movement of material values of goods in space.Данная статья имеет своей целью рассмотрение внешнесредовых аспектов, которые влияют на инновационную активность логистических операторов и определяют основные направления инноваций на логистическом рынке. Изложение материалов по теме статьи позволяет сформировать следующие основные выводы, полученные в ходе работы: мировой логистический рынок активно развивается и в настоящее время проходит этап качественного обновления, что связано с изменением роли логистических операторов при оказании ими услуг своим клиентам (переход от иерархической к партнерской форме взаимодействия); с организационно-экономической точки зрения мировой логистический рынок образован двумя ключевыми сегментами (b-2-b business-to-business и b-2-c business-to-customer), в рамках которых осуществляют свою деятельность три ключевых типа логистических операторов; инновации в логистической сфере стоит рассматривать и как ключевой фактор создания высокой добавленной стоимости логистических услуг, и как основу формирования высокой ценности этих услуг для клиентов; совокупность инноваций, призванных повышать добавленную стоимость в логистических услугах и их ценности для клиентов, необходимо рассматривать как с точки зрения организации управления логистическим потоком, так и с точки зрения физической организации движения грузов материальных ценностей в пространстве