检索结果-南通市图书馆

Optimization Problem for the Integral Model of Developing systems

在线全文

学校读者我要写书评

暂无评论

Journal of the Operations Research Society of China 2022年第4期10卷 817-833页

作者： Evgeniia Markova Inna Sidler Victor Trufanov melentiev energy systems institute of siberian branch of the russian academy of sciences Irkutsk664033Russia

This paper addresses an integral model of development a large electric power system using the example of the Unified energy System of Russia.The model takes account of the age structure of the plants main equipment.Besides,generating equipment is divided into components depending on the types of energy resources used.The mathematical model is presented by a system of nonclassical Volterra integral equations of the first kind.One of the equations describes the balance between the total available capacity of the electric power system,commissioning of new equipment,and dismantling of obsolete one.The other equations define the shares of different types of power plants in the total composition of the electric power system equipment.Based on the considered model,we set a problem that searches the optimal lifetimes of electric power system capacities for a given demand for electricity.The optimality criterion is a functional reflecting cost of commissioning and operating the capacities.The specifics of the optimization problem are that the optimization parameter is in the lower limit of integration.An algorithm for solving of this optimal control problem numerically is developed.The influence of economic indices on the solution to the optimal control problem is studied.Calculations of the optimal development of the Unified energy System of Russia until 2050 are carried out using real-life data.

关键词： Optimization problem Integral model Lifetime

Environmental performance assessments of different methods of coal preparation for use in small-capacity boilers: experiment and theory

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Coal Science & Technology 2023年第5期10卷 57-71页

作者： A.N.Kozlov E.P.Maysyuk I.Yu.Ivanova melentiev energy systems institute of siberian branch of the russian academy of sciences Irkutsk130Lermontov664033Russia

The purpose of this article is to receive environmental assessments of combustion of different types of coal fuel depending on the preparation(unscreened,size-graded,briquetted and heat-treated)in automated boilers and boilers with manual load-ing.The assessments were made on the basis of data obtained from experimental methods of coal preparation and calculated methods of determining the amount of pollutant and greenhouse gas emissions,as well as the mass of ash and slag waste.The main pollutants from coal combustion are calculated:particulate matter,benz(a)pyrene,nitrogen oxides,sulfur dioxide,carbon monoxide.Of the greenhouse gases carbon dioxide is calculated.As a result of conducted research it is shown that the simplest preliminary preparation(size-graded)of coal significantly improves combustion efficiency and environmental performance:emissions are reduced by 13%for hard coal and up to 20%for brown coal.The introduction of automated boil-ers with heat-treated coal in small boiler facilities allows to reduce emissions and ash and slag waste by 2-3 times.The best environmental indicators correspond to heat-treated lignite,which is characterized by the absence of sulfur dioxide emissions.

关键词： Coal preparation Automated and hand-fed coal boilers Environmental performance metrics

Development of a methodology for assessing the adequacy of electric power systems

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Global energy Interconnection 2022年第5期5卷 543-550页

作者： Dmitry S.Krupenev Denis A.Boyarkin Dmitrii V.Iakubovskii melentiev energy systems institute of siberian branch of the russian academy of sciences Lermontov str.130Irkutsk664033Russia

This study presents the results of a research into the developing a methodology for assessing the adequacy of advanced electric power systems characterized by the integration of various innovative technologies,which complicates their analysis.The methodology development is aimed at solving two main problems:(1)increase the adequacy of modeling the processes that occur in the electric power system and (2)enhance the computational efficiency of the adequacy assessment methodology.This study proposes a new mathematical model to minimize the power shortage and enhance the adequacy of modeling the processes.The model considers quadratic power transmission losses and network coefficients.The computational efficiency of the adequacy assessment methodology is enhanced using efficient random-number generators to form the calculated states of electric power systems and machine learning methods to assess power shortages and other reliability characteristics in the calculated states.

关键词： Electric power systems Adequacy Power shortage minimization Pseudo-and quasi-random number generation Machine learning methods.

Caspian energy Ring: Prospective vision

在线全文

学校读者我要写书评

暂无评论

Global energy Interconnection 2022年第5期5卷 461-471页

作者： Sergei Podkovalnikov Lyudmila Chudinova Ivan L.Trofimov Leonid Trofimov melentiev energy systems institute of siberian branch of the russian academy of sciences 130Lermontov Str.Irkutsk664033Russia

This paper presents the results of a technical and economic optimization study of the prospects of the Caspian energy Ring(CER),connecting power systems of Russia,countries of the Caucasus,Central Asia,and South Asia.The CER,belonging partly to the emerging Asian Supergrid and partly to the existing European Supergrid,will become a bridge connecting these supergrids,laying the foundation for forming a global energy interconnection in the long term.The expansion of carbon-free renewable and nuclear facilities,low-carbon gas-fired power plants,and traditional thermal and hydro energy sources within the CER were considered in this study.The positive economic benefits of the creation of the CER are presented.Preliminary characteristics of the potential CER were also estimated.

关键词： Caspian energy Ring Interstate electric power grids Transmission lines Installed capacity Power generation Economic viability.

Corporate governance in generating companies of the russian electric power industry in the context of ESG agenda

在线全文

学校读者我要写书评

暂无评论

Global energy Interconnection 2022年第5期5卷 512-523页

作者： Galina I.Sheveleva melentiev energy systems institute of siberian branch of the russian academy of sciences 130 Lermontov St.Irkutsk 664033Russia

To address the issues of investment appeal in the russian electric power industry,this study analyzes the dynamics of corporate governance,including permanent redistribution of property and compliance with the russian Corporate Governance Code,in wholesale and territorial-generating companies.The increasing concentration of property in the hands of the state and its implications for investors are also noted.This study reveals the violations of essential principles,and the substantial differences in corporate governance practices,in the best-and worst-performing companies.Additional standards for better corporate governance practices to benefit the investors in the context of the current Environmental,Social,and corporate Governance(ESG)agenda are proposed.This study provides a new insight at the development of corporate governance in russian power generating companies through property redistribution and compliance with corporate governance principles.

关键词： Corporate governance russian power generating companies ESG agenda

Medium-term scheduling of operating states in electric power systems

在线全文

学校读者我要写书评

暂无评论

Global energy Interconnection 2022年第5期5卷 472-483页

作者： Aizenberg N. Palamarchuk S. melentiev energy systems institute Siberian Branch of the Russian Academy of Sciences664033130 Lermontov st.IrkutskRussia

This article presents a mathematical model for the medium-term scheduling of the operating states of electric power systems.The scheduling period is divided into several time intervals.The model can be used to determine the equilibrium state in which each supplier earns maximum profit from supplying electricity to the wholesale market.We estimated the maximum value of public welfare,which indicates the total financial gains of suppliers and consumers,to determine the prices at the nodes of the power system.This was done by considering the balance constraints at the nodes of the power system and constraints on the allowable values of generation,power flows,and volumes of energy resources consumed over several time intervals.This problem belongs to the class of bi-level Stackelberg game-theoretic models with several leaders.The market equilibrium is modeled simultaneously in several intervals,given the multiplicity and duration of interactions.We considered two approaches for solving the multi-interval equilibrium state problem.The first approach involved directly solving a system of joint optimality conditions for electricity suppliers and consumers.The second approach involved iterative searches until the equilibrium state was reached.This article presents the results of medium-term scheduling using a case study of a simplified real-world power system.

关键词： Scheduling Mathematical model Optimality conditions Imperfect competition Equilibrium state Nodal prices.

The evolution of interstate power grid formation

在线全文

学校读者我要写书评

暂无评论

Global energy Interconnection 2021年第4期4卷 335-353页

作者： Nikolai Voropai Sergei Podkovalnikov Lyudmila Chudinova melentiev energy systems institute of siberian branch of the russian academy of sciences 130Lermontov Str.Irkutsk 664033Russia

This study analyzes the process of electric power system integration in various regions worldwide.This process is implemented by creating both interstate electric ties and power grids.The analysis is comprehensive and examines the system,spatial,technical,organizational,and market aspects of the integration.Various countries,including developed countries such as Europe and North America,as well as economically developing countries such as Central America and Africa,are involved in this process.However,the rates and scales of electric power integration differ across various regions worldwide.The analysis shows that the process of electric power integration,which has decades of history,is still ongoing,despite the growth of other trends,such as the development of distributed generation.Further electricity integration is expected to lead to the formation of a global power interconnection in the long term.

关键词： Interstate electric power grids/interconnections Interstate electric ties

Evaluation of the energy efficiency of rotary percussive drilling using dimensionless energy index

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2022年第5期14卷 1486-1500页

作者： V.N.Oparin V.N.Karpov V.V.Timonin A.I.Konurin Chinakal institute of Mining Siberian BranchRussian Academy of SciencesKrasnyi Prospect 54Novosibirsk630091Russia

This paper sets forth a geomechanics framework for assessing the energy efficiency of rotary percussive drilling using the energy criterion, which has been proposed by Victor Oparin for volumetric destruction of high-stress rocks having nonuniform physico-mechanical properties. We review the long-term research and development in the specified area of science and technology, including research and development projects implemented at the institute of Mining, siberian branch of the russian academy of sciences. A new modified expression of Oparin’s dimensionless energy criterion of volumetric rock destruction k is introduced. The range of in situ values is determined for the energy criterion of volumetric rock destruction at the optimized energy efficiency of rotary percussive drilling. The temporospatial intervals of geotechnical monitoring are found to control pneumatic drilling energy efficiency at subsoil use objects in Russia. The integrated experimental, theoretical and geotechnical approach to the comprehensive investigation of real-time processes of rock fracture in rotary percussive drilling using the energy concept possesses the necessary geomechanical performance-and-technology potential to create the next level geotechnical monitoring of drilling systems for various purposes, including determination of physico-mechanical properties and the stress-strain analysis of rock mass in full-scale drilling.

关键词： Rotary percussive drilling Geotechnical monitoring Drilling machine energy criterion energy efficiency

Factors associated with trabecular bone score in postmenopausal women with type 2 diabetes and normal bone mineral density

在线全文

学校读者我要写书评

暂无评论

World Journal of Diabetes 2022年第7期13卷 553-565页

作者： Olga N Fazullina Anton I Korbut Vadim V Klimontov Laboratory of Endocrinology Research Institute of Clinical and Experimental Lymphology-Branch of the Institute of Cytology and GeneticsSiberian Branch of Russian Academy of SciencesNovosibirsk 630060Russia

BACKGROUND Osteoporosis and type 2 diabetes(T2D)have been recognized as a widespread comorbidity leading to excess mortality and an enormous healthcare burden.In T2D,bone mineral density(BMD)may underestimate the risk of low-energy fractures as bone quality is reduced.It was hypothesized that a decrease in the trabecular bone score(TBS),a parameter assessing bone microarchitecture,may be an early marker of impaired bone health in women with T2D.AIM To identify clinical and body composition parameters that affect TBS in postmenopausal women with T2D and normal BMD.METHODS A non-interventional cross-sectional comparative study was conducted.Potentially eligible subjects were screened at tertiary referral center.Postmenopausal women with T2D,aged 50-75 years,with no established risk factors for secondary osteoporosis,were included.BMD,TBS and body composition parameters were assessed by dual-energy X-ray absorptiometry.In women with normal BMD,a wide range of anthropometric,general and diabetes-related clinical and laboratory parameters were evaluated as risk factors for TBS decrease using univariate and multivariate regression analysis and analysis of receiver operating characteristic(ROC)curves.RESULTS Three hundred twelve women were initially screened,176 of them met the inclusion criteria and underwent dual X-ray absorptiometry.Those with reduced BMD were subsequently excluded;96 women with normal BMD were included in final analysis.Among them,43 women(44.8%)showed decreased TBS values(≤1.31).Women with TBS≤1.31 were taller and had a lower body mass index(BMI)when compared to those with normal TBS(Р=0.008 and P=0.007 respectively).No significant differences in HbA1c,renal function,calcium,phosphorus,alkaline phosphatase,PTH and 25(ОН)D levels were found.In a model of multivariate linear regression analysis,TBS was positively associated with gynoid fat mass,whereas the height and androgen fat mass were associated negatively(all P<0.001).In a multiple logistic regression,TBS≤1.31 was associated with lower gynoid f

关键词： Diabetes Osteoporosis Bone mineral density Trabecular bone score Obesity Body composition