System Research in Energy最新文献

{"title":"Estimation of the potential of low grade heat sources for heat pump plants in district heating systems","authors":"V. Derii, I. Sokolovska, O. Teslenko","doi":"10.15407/srenergy2022.01.004","DOIUrl":"https://doi.org/10.15407/srenergy2022.01.004","url":null,"abstract":"Methodology and calculation formulas are proposed for estimating the thermal potential and its distribution by the regions of Ukraine for natural and artificial (anthropogenic) low-grade heat sources: ambient air, ventilation emissions of buildings connected to district heating systems, soils and groundwater, large rivers, wastewater, waste heat of boilers and CHPs, and industrial waste heat. The availability of thermal potential of these sources for heat pump plants of district heating systems has been determined. Annual heat potential and average annual capacity were estimated for each of these sources. It is shown that the annual heat potential and average annual capacity available for heat pump plants in district heating systems are: 9,735 thous. Gcal and 905 MW for ambient air; 25,655 thous. Gcal and 1,871 MW for ventilation emissions of buildings; 2,628 thous. Gcal and 87 MW for soil and groundwater; 3,212 thous. Gcal and 299 MW for large rivers; 4,545 thous. Gcal and 338 MW for wastewater; 2,459 thous. Gcal and 724 MW for waste heat of boilers and CHPs; 7,661 thous. Gcal and 214 MW for industrial waste heat, respectively. The total thermal potential of the above-mentioned sources is 4.97 GW which enables the use of heat pump plants in district heating systems with a total capacity of about 7.5 GW. In the case of heat pump plants using low grade heat sources of natural origin, it must be taken into account that their intensive use can lead to their rapid thermal exhaustion and a significant impact on the environment. Therefore, it is necessary to maintain such level of energy use of natural low grade heat sources that would enable their exploitation without harming the environment. In the conditions of densely built-up cities of Ukraine, the use of heat of the soil and groundwater for heat pump plants will be limited due to the shortage of free land plots. It will also be problematic to use powerful air heat pump plants in populated areas due to their high noise level. Keywords: heat pump plant, district heating systems, low grade heat source, thermal potential","PeriodicalId":307644,"journal":{"name":"System Research in Energy","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125666353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Overview of trends and prospects of electric transport development in the EU and assessment of economic / «climate» efficiency of electromob operation","authors":"N. Ivanenko","doi":"10.15407/srenergy2022.02.013","DOIUrl":"https://doi.org/10.15407/srenergy2022.02.013","url":null,"abstract":"The share of electric vehicles in the world's total vehicle fleet is growing rapidly, given the urgency of global climate change and the limited resources of fossil fuels. Another important aspect is the impact of the electric vehicles use on the functioning of power systems, for example for voltage regulation, which is important for the functioning of the UES of Ukraine against the background of declining electricity consumption. It should be noted that important feature of EV is the opportunity to change charging consumption during the day. It is possible to remove charging consumption to the night time due to different regulatory and/or stipulating measures. Certain advantages and disadvantages of EV are identified, which allows making an informed choice. In particular, the biggest advantages are the economic and «climatic» efficiency of their operation, and the biggest disadvantages are the high cost of EV and batteries, as well as the limited infrastructure of charging stations. Given technological progress, many shortcomings are becoming less significant. The aim of the article is to analyze the state and prospects of development of the electric car fleet in the EU, as well as to assess the environmental and «climatic» efficiency of EV operation per 1 km. A method for assessing the environmental and «climatic» efficiency of operation of electric vehicles per 1 km is proposed, which allows to determine in which countries these indicators are more favorable for the development of electric transport, and in which it is necessary to use stimulating legislative measures. An assessment of the environmental and «climatic» efficiency of electric vehicles in the EU are given. It is determined that the environmental efficiency of EV operation in Europe is from 9 to 18 eurocents per 1 km. «Climatic» efficiency of EV operation in Europe is from 5 to 20 g of CO2 per 1 km. For comparison, these figures in Ukraine are 15 eurocents per 1 km and 20 g of CO2 per 1 km. Keywords: sustainable transportation development, electric vehicles, energy efficiency, «climate» efficiency","PeriodicalId":307644,"journal":{"name":"System Research in Energy","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115987286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coatings properties Cr-Si-B-MgC2 in high conditions temperatures Language: Ukrainian","authors":"V. Shchepetov, S. Kovtun, S. Kharchenko","doi":"10.15407/srenergy2022.01.046","DOIUrl":"https://doi.org/10.15407/srenergy2022.01.046","url":null,"abstract":"Heat resistance, as well as friction and wear of composite coatings Cr–Si–B–MgC2 under conditions of elevated temperatures implemented in friction pairs, were investigated. The selection of the Cr–Si–B–MgC2 composition and its optimal composition for spraying wear-resistant coatings loaded with friction at high temperatures are substantiated. Indicated the main influence on the properties, structure, and stability of heterogeneous coatings is exerted by alloying elements at certain concentrations, as well as technological parameters of coating application. It has been established that silicon and boron contribute to the formation of complex-alloyed high-temperature formations with increased wear resistance. The microhardness of coatings correction is realized due to the silicon percentage content, while the mechanical properties of the material are increased by additional doping with boron and magnesium carbide. The parameters of sputtering of coatings are also important, on which the formation of a heat-resistant layer directly depends. It was experimentally established that the ratio of consumption of acetylene and oxygen ~20/25 l/min ensures the stability of technological parameters of sputtering, homogeneity of the chemical composition and constancy of coating properties. At a load of up to 5.0 MPa, a sliding speed of up to 1.2 m/s and a temperature of up to 700С, the coatings of the Cr–Si–B–MgC2 system show stable structural adaptability, which ensures the minimization of friction and wear parameters. Metallographic analysis and profilography of the samples indicate that there are no visible damages on the friction surfaces, and individual sticking points are localized in thin film surface layers. It was established that the dependence of the microhardness of the surface structures on the temperature is monotonic, but jumps are also observed if polymorphic transformations or transformations of metastable states into more stable and stable ones during heating and cooling occur. Microhardness indicators are uniform because particles of inclusions and impurities are dissolved in the oxide structures, which significantly affect the microhardness, and therefore, the properties of oxides of both simple and complex compositions. Keywords: protective coatings, surface layer, resistance to oxidation, wear resistance, heat resistance","PeriodicalId":307644,"journal":{"name":"System Research in Energy","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131006725","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Review of the state of air pollution by energy objects in Ukraine","authors":"Artur O. Zaporozhets, V. Babak, A. Sverdlova, L. Shcherbak, Y. Kuts","doi":"10.15407/srenergy2022.02.042","DOIUrl":"https://doi.org/10.15407/srenergy2022.02.042","url":null,"abstract":"Objective information about the state of air pollution is the basis for implementing measures to ensure conditions for the safe living of the population and improve the environmental pollution monitoring network. The purpose of the work is to study the impact of energy facilities (enterprises consuming different types of fuels) on atmospheric air pollution and its spatial and temporal distribution in cities and regions of Ukraine. The relevance of the work is confirmed by the fact that Ukraine, according to the World Health Organization, has the highest mortality rate from diseases caused by polluted air. The article considers general approaches to the functioning of the air pollution monitoring system in Ukraine and the features of the formation of the local air pollution index. The article discusses the most common pollutants generated at energy-intensive enterprises in Ukraine, in particular benzo(a)pyrene (C20H12), sulfur dioxide (SO2), dust, carbon monoxide (CO), nitrogen oxides (NxOy), hydrogen sulfide (H2S), carbon disulfide (CS2), hydrogen fluoride (HF), ammonia (NH3), phenol (C6H6O) and others. Statistical information about emissions of pollutants (CO2, SO2, NO2, CO, PM10, PM2,5, PAHs, Zn, Pb, Cu, Cr, Ni, As) into the air from stationary sources of pollution for the period 1990-2018 was analyzed and visualized. The dynamics of chemical air pollution in different cities and regions of Ukraine are analyzed in detail. For some cities (Kyiv, Dnipro, Odesa, Kharkiv), energy-intensive enterprises and types of pollutants emitted into the air have been identified. It is shown that among the most polluted cities are Mariupol, Dnipro, Odesa, Kamianske, Kyiv, Kryvyi Rih, Lutsk, Lysychansk, Mykolaiv, Sloviansk, Kramatorsk, Rubizhne, Lviv, Zaporizhzhia, Lysychansk, Kherson, Kremenchuk, and among the most polluting regions are Donetsk, Dnipropetrovsk, Ivano-Frankivsk, Zaporizhzhya, Lviv, Vinnytsia, Kyiv, Cherkasy, Poltava. These regions need priority implementation of modern air pollution monitoring systems. Keywords: air pollution, chemical pollution, stationary sources, energy objects, pollution dynamics, maximum permissible concentration","PeriodicalId":307644,"journal":{"name":"System Research in Energy","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121713083","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Review of passive loop systems for normalization of high-voltage cable line magnetic field","authors":"V. Grinchenko, O. Tkachenko, Tetyana Bilan","doi":"10.15407/srenergy2022.02.073","DOIUrl":"https://doi.org/10.15407/srenergy2022.02.073","url":null,"abstract":"The paper is devoted to the review of known passive loop systems that can be used to normalize the high-voltage cable line magnetic field. The purpose is to identify the most promising systems. We review the most cited scientific papers and patents about the reduction of the power line magnetic field. We identify the top research groups engaged in the design of passive loop systems. The two groups are from Italy, the one each is from Spain and Ukraine. The passive loop systems developed by each group have their own features. We classify the systems according to the following characteristics: the number of passive loops in the shielding system, the shape of passive loops used in the shielding system, and the way to increase the shielding efficiency of cable line magnetic field. According to the number of passive loops, the systems can be divided into three types: single-element, double-element and multi-element. According to the shape of passive loops, two types of shielding systems can be distinguished, namely, the systems using rectangular passive loops and the systems using passive loops made of three cables connected in parallel. According to the method of the shielding efficiency increasing, the system can be divided into four types: the first use ferromagnetic cores covering power and shield cables, the second use additional capacitors connected to shield cables, the third use a unique arrangement of loops between the cable line and the shielding area, the fourth use an increase in the cross-section of shield cables, respectively, an increase in the quantity of metal. The review shows the most promising passive loop systems for normalizing the high-voltage cable line magnetic field are single-element systems with additional cores, namely «High Magnetic Coupling Passive Loop» and «Single-loop shield with ferromagnetic cores and asymmetric magnetic coupling». Keywords: magnetic field, shielding, cable line, reference level, power frequency","PeriodicalId":307644,"journal":{"name":"System Research in Energy","volume":"125 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121027313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a methodology for managing the load regime of the unified energy system of ukraine, using new principles of regulating the generating capacities of nuclear, solar and wind power plants","authors":"E.A. Lenchevsky, O. Godun","doi":"10.15407/srenergy2022.02.022","DOIUrl":"https://doi.org/10.15407/srenergy2022.02.022","url":null,"abstract":"The article considers promising directions for the construction of new systems for regulating the generating capacity of nuclear, solar and wind power plants, capable of changing and improving the processes of managing the load regime of the unified energy system of Ukraine. Conducted studies have shown that with the implementation of new systems, there is a real opportunity to abandon modern but too expensive means of maneuverable generation, such as reserve stations with highly maneuverable TPPs, as well as frequency control support systems (FCS) using powerful storage batteries. In contrast to this, it is offered in the processes of managing the regime of the unified energy system of Ukraine, applying the new principles and means of regulating the generating capacities of NPPs, as well as WPPs and SPPs. For this, it will be necessary to create reserves from the automatically controlled load of powerful EC electric boilers in the OESU. At the same time, only the automated dispatching control system (ADСS) will perform the load regulation processes of powerful ECs. It is assumed that the information data on the current load regulation parameters of the ECs complexes will be sent to the ADСS from specialized tools built on the basis of the use of information and measurement technologies (IMT) developed at the Institute of General Energy on NAS of Ukraine. The result of the conducted research is the development of methodical approaches to the management of the OES regime, using new principles of regulation of generating capacities both in the power grid of NPPs and in the cities where WPPs and SES are installed. Keywords: power system, electric heat generators, load schedule, control system","PeriodicalId":307644,"journal":{"name":"System Research in Energy","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122128057","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mathematical model for forecasting hydrocarbon production based on time dependences of development periods of oil and natural gas fields","authors":"M. Kaplin, Tetyana Bilan, V. Makarov, M. Perov","doi":"10.15407/srenergy2022.01.029","DOIUrl":"https://doi.org/10.15407/srenergy2022.01.029","url":null,"abstract":"An optimization model for forecasting hydrocarbon production in uncertain information conditions regarding the prospects for the development of natural gas and oil resources and reserves is proposed. The model is based on the presentation of options for the development of active fields with approximate dependences of the volume of potential annual production on the implemented measures and technologies for increasing the efficiency of gas extraction, as well as statistical information on the distribution of new fields by the reserves and depths volume of occurrence with the corresponding costs for the field’s development. In order to take into account the characteristic patterns of exploitation of natural gas and oil fields in the objective of forecasting the development of the relevant sectors of the country's economy, approximate time dependences of the production volume of a hydrocarbon field during a limited period of its development are proposed. The method of using sets of binary variables to represent the non-smooth and non-linear dependences of hydrocarbon resource extraction volumes on time during the periods of field development is presented. The optimization approach basis to the problem of forecasting the development of the oil and gas production industry regarding the substantiation of the expedient terms of putting new natural gas and oil fields into operation, taking into account the possibilities of intensifying the production of existing fields, is proposed. The optimization model for forecasting hydrocarbon production can be considered as a methodical tool for developing programs for the development of oil and gas production in the country in the context of solving applied planning problems. The calculations result of forecast volumes of natural gas production, obtained using the developed software and information support of the model, are presented. The implemented algorithms of non-linear optimization made it possible to form a volume forecast of natural gas production in Ukraine for the period until 2040, which takes into account the types of natural gas deposits available in the country and the possibility assessment of their development over time. Keywords: gas industry, forecasting, mining, technology, production forecasting model","PeriodicalId":307644,"journal":{"name":"System Research in Energy","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125101221","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Review of the current state and development perspectives of the solar energy in Ukraine","authors":"A. Sverdlova","doi":"10.15407/srenergy2022.01.019","DOIUrl":"https://doi.org/10.15407/srenergy2022.01.019","url":null,"abstract":"This paper analyzes the prospects for developing solar power generation systems and the economic feasibility of further industry development. The state of global solar energy, its expansion potential, and Ukraine's position in the total statistics are examined. The rate of increase in the introduction of alternative types of energy has been determined. Statistical data on the number of commissioned power plants and the electricity they produced were analyzed. Solar energy is one of the most promising and powerful renewable energy sources. As a result of the analysis, it was concluded that Ukraine is gradually taking essential steps to expand the use of solar energy, developing a regulatory and legislative basis for the service, implementation, optimization, and stimulation of households to implement and build solar power plants. The relevance and expediency of the use of solar energy in connection with the constant growth of the cost of electricity and the future forecast of the increase of public investments in the industry at the global level are characterized. According to the analysis of statistical data and forthcoming plans for solar energy development, high rates of its growth in Ukraine have been determined. The consequences the war has on the solar energy industry are described. It is explained that, due to the war, half of the renewable energy objects are under threat of complete or partial destruction, in particular, 47% of solar power plants are located in regions where active fighting continues. The general trend of post-war development will be an increase in the share of solar energy in the overall energy balance. This will be facilitated by eliminating financial and legislative restrictions on the development of renewable energy, expanding opportunities for the export of electricity from renewable energy sources, and considering the green course, which is focused on clean energy. Keywords: alternative energy, renewable energy sources, solar power plants, electric energy","PeriodicalId":307644,"journal":{"name":"System Research in Energy","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128878327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Overview of materials and coatings emission coefficient control methods","authors":"O. Dekusha, Svitlana Kovtun, Z. Burova","doi":"10.15407/srenergy2022.02.053","DOIUrl":"https://doi.org/10.15407/srenergy2022.02.053","url":null,"abstract":"The emissivity of a coating and materials determines the intensity of radiation heat exchange on the surface of the object under study. Therefore experimental determination is important to ensure the necessary thermal protection characteristics of structures. The article considers methods of emissivity control, which are currently regulated by the main standards ASTM E408-13, ISO 9050:2003, C835-06, C1371-15. The methods of experimental determination of the emissivity can be divided into two large groups: optical and thermal. Spectrometric is the most widespread optical method. The technique of spectrometric research in determining the curve of specular reflection, measured in a wide range of wavelengths at an angle of incidence of the radiation close to normal. Based on the obtained results, the average value of the normal and hemispherical emissivity of the surface is calculated. Among the thermal methods of experimental determination of the emissivity the following have become widespread: radiation, calorimetric, regular mode method, and the method of continuous heating at a constant rate. The stationary systems with a wide range of research temperatures and portable express devices for control at temperatures close to room temperature are used to measure the emissivity. In stationary systems for measuring the emissivity, which apply thermal methods, heat fluxes between the object under investigation and some emitter, as well as the temperature of the structure elements, are usually determined. But these methods cannot be used in the control of products. Therefore, it is promising to develop a method for measuring the emissivity which will non-destructive and in same do not require additional standard samples for comparations. Keywords: express control, emissivity, emissometers, spectrophotometers, reflectometers","PeriodicalId":307644,"journal":{"name":"System Research in Energy","volume":"166 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132067921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A stochastic and dynamic approach in simulating spread processess of malwareof automated energy facilities and their systems","authors":"V. Khaidurov","doi":"10.15407/srenergy2022.01.053","DOIUrl":"https://doi.org/10.15407/srenergy2022.01.053","url":null,"abstract":"The rapid development of information technologies in today's conditions makes it possible to control and automate processes and enterprises, institutions to ensure the correct and efficient operation of various energy systems. The mathematical apparatus used in the software for such objects and systems makes it possible to manage their states in various regular conditions. Sometimes unpredictable factors arise in the operation of energy facilities, which can lead to global catastrophes not only for a particular region, but also for all of humanity is the deliberate damage to the logic of the software that controls all the processes of the power system is one of these factors, for the purpose of terror or other malicious purposes. Such factors require the construction of models with which it is possible to predict the scale of risk and extent of damage, as well as to obtain a general estimate of the costs of protecting power system software against such malicious actions. An optimization mathematical model and a corresponding description of the implementation of a complex software tool for modeling the spread of malicious software (malware) in modern energy facilities and systems is the result of the work. The developed optimization mathematical model is based on the use of methods of optimization of functions and functionals with restrictions in the form of systems of ordinary differential equations with given corresponding initial conditions. To develop process simulation software modules based on the PSIDR mathematical model, stochastic population methods, models and algorithms were used to determine the control parameter at each time step. The use of such optimization methods and algorithms makes it possible to solve more complex tasks. It requires a procedure for predicting the spread of processes of various origins in general. The developed mathematical model consists in the minimization of costs for the purchase of antiviruses for the protection of relevant systems in energy facilities and systems. Keywords: malware, prediction, optimization, stochastic model, deterministic model, cellular automaton, energy objects","PeriodicalId":307644,"journal":{"name":"System Research in Energy","volume":"PP 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-12-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126443186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}