Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu最新文献

{"title":"Establishing the influence of the quarry depth on the indicators of cyclic flow technology during the development of non-ore deposits","authors":"B. Sobko, O. Lozhnikov, M. Chebanov, V. Kriachek","doi":"10.33271/nvngu/2024-1/005","DOIUrl":"https://doi.org/10.33271/nvngu/2024-1/005","url":null,"abstract":"Purpose. To determine the efficiency of the cyclic flow technology at the development of non-ore deposits depending on the location of haulage level, mobile crushing and sorting plants with variable productivity of the enterprise. Methodology. The research implemented the following methods: analytical method – to establish the dependence of the required number of dump trucks at the enterprise on the depth of non-ore quarry development at a given annual productivity; simulation modelling – to determine the influence of the mining depth of a non-ore quarry on the haulage distance of mining mass to the surface of the quarry. Findings. The performance indicators of the haulage system for the development of a non-ore quarry using dump trucks and conveyor transport in combination with a mobile crushing complex, as well as a mobile crushing and sorting plant on the haulage level, were determined. It was established that the use of cyclic flow technology with a mobile crushing complex on the haulage level allows reducing the haulage distance by 1.9 times at a quarry depth of 150 m. Originality. The dependence of the dump trucks productivity and their required number on the depth and production capacity of a non-ore quarry when using the haulage mining system was established. It was determined that an increase in the quarry depth from 50 to 150 m will lead to an increase in the number of dump trucks by 2.6 to 3.6 times, depending on the quarry productivity. At the same time, the use of cyclic flow technology with a mobile crushing complex in the quarry allows increasing the productivity of dump trucks by 2.1 times from 94.1 to 197.6 thousand tons/year due to the reduction of the haulage distance of dump trucks from 2525 to 575 m. Practical value. A methodology for determining the impact of the quarry depth on the parameters of the mining haulage complex has been developed when using the technique of cyclic and current action on non-ore raw material quarries, which takes into account the location of the mobile crushing and sorting plant, changes in the depth and annual productivity of the quarry, its area and parameters of the trenches. The indicators of the cyclical-flow mining technology, necessary for the further technical and economic assessment of the proposed solutions, have been established.","PeriodicalId":19101,"journal":{"name":"Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu","volume":"28 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140411847","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":"Investment policy of construction enterprises under the conditions of marital state","authors":"O. Iastremska, T. Ivanova, T. Ordukhanov, O. Denysiuk, M. Zinchenko","doi":"10.33271/nvngu/2024-1/197","DOIUrl":"https://doi.org/10.33271/nvngu/2024-1/197","url":null,"abstract":"Purpose. Studying the investment policy in construction in wartime conditions, namely: determining the general characteristics of the investment process in construction in wartime conditions; identification of factors affecting investment activity; analysis of the problems of investment activity in these conditions; development of recommendations for improvement of investment policy in construction in wartime conditions. Methodology. In the process of studying the investment policy of construction enterprises in the conditions of martial law, the following methods were used: expert assessment (allowed obtaining conclusions and recommendations regarding the possibilities of investing in construction projects in conditions of military conflict), scenario modeling (development of various scenarios investing in the construction sector made it possible to analyze the possible consequences and results of each of them), system analysis (taking into account the relationships between various aspects of the investment policy of construction enterprises and its impact on the economy and society as a whole) and marketing research (determining the needs and requirements of the market in relation to investments in the construction sector in the conditions of a military conflict). Findings. The authors indicated the main problems of construction financing: lack of long-term loans and investments for construction; high interest rates on loans; imperfect legislation in the field of construction; lack of transparency and efficiency in the management of public finances allocated for construction. It is proposed to take the following measures: to create conditions for attracting long-term loans and investments in construction; to reduce interest rates on loans; to improve legislation in the field of construction; to improve the transparency and efficiency of the management of public finances allocated for construction; to improve mechanisms of public-private partnership in the field of construction; to develop programs to stimulate housing construction for low-income citizens; to create conditions for the development of small and medium-sized enterprises in the field of construction. To form the investment attractiveness of the construction industry in Ukraine, the authors suggest creating a favorable investment climate that will guarantee investors the protection of their rights and interests; developing transparent and effective rules and procedures for regulation of construction; ensuring access to quality construction materials and equipment at competitive prices; improving the qualification and level of professional training of construction personnel. Originality. The article comprehensively researches the investment policy in construction in the conditions of war for the first time. The authors revealed new regularities in the development of the investment process in construction under martial law, developed recommendations for its improvement. Practical value","PeriodicalId":19101,"journal":{"name":"Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu","volume":"37 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140415393","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":"Advantages of using CONCRETE CANVAS materials in railway track construction","authors":"B. Eller, S. Szalai, M. Sysyn, D. Harrach, J. Liu","doi":"10.33271/nvngu/2024-1/050","DOIUrl":"https://doi.org/10.33271/nvngu/2024-1/050","url":null,"abstract":"Purpose. Justification of the feasibility of using new types of drainage materials, such as Concrete Canvas (CC), under the upper structure of the railway permanent way. Methodology. The tasks were solved by a complex research method, including analysis and generalization of literary and patent sources, analytical, experimental studies, using computer and mathematical modeling methods. Tests were conducted with and without the CC layer in a multi-level shear box. After the shear test, the specimens were also tested for load-bearing capa­city (E2, according to the Hungarian standard) and particle breakage. The contact surface between the bottom of the ballast and the CC was measured using a precision 3D laser scanner (GOM ATOS) and visualized graphically using AutoCAD software. Findings. Experimental testing of the vertical load during connection and analysis compared with the test results of geocomposite/geogrid structures, internal shear resistance, and other parameters proved the structure’s higher load-bearing capacity with the CC layer. Based on the results, the Concrete Canvas structure provides higher reinforcement than the average geogrid type. Originality. The advantages of using new Concrete Canvas materials in the structure of a railway track have been demonstrated for the first time to provide greater internal shear resistance than the average for geogrids. Practical value. These results may provide primary data for using Concrete Canvas in railway tracks and superstructures in the future.","PeriodicalId":19101,"journal":{"name":"Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu","volume":"6 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140410130","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":"Justification of geodetic monitoring methodology of the retaining walls on the example of the embankment in Kremenchuk","authors":"P. Mikhno, I. Shelkovska, V. Kozar, O. Kliuka, Y. Trehub","doi":"10.33271/nvngu/2024-1/076","DOIUrl":"https://doi.org/10.33271/nvngu/2024-1/076","url":null,"abstract":"Purpose. Development of a methodology for analyzing the results of geodetic measurements according to which it is possible to use the materials of past years for the needs of geodetic monitoring on the example of a retaining wall in the conditions of the city’s recreational area. Methodology. A technological scheme of geodetic monitoring of retaining walls has been developed with four main stages: analysis of initial data, design of geodetic monitoring, periodic observations, processing and analysis of geodetic monitoring results. The conditions of the recreational areas of the city determine the specifics of geodetic monitoring, limit the possibilities of choosing a scheme of the geodetic network and methods of measurements. In this regard, it is proposed to develop models of the development of deformation processes already at the first stage of geodetic monitoring, which will allow geodetic monitoring to be carried out with greater reliability in the future and avoid possible forecasting errors. Findings. The results of the analysis of geodetic measurements in the geodetic networks of Kremenchuk (coordinates and heights of wall signs) show the presence of horizontal and vertical displacements of the retaining wall. In the horizontal plane the retaining wall has shifted in the south-western direction, towards the Dnipro River. In the vertical plane, the retaining wall has subsided. The displacements of different parts of the retaining wall are uneven. The average annual rate of both horizontal and vertical displacements is equivalent and is approximately 1 mm/year. The values of absolute displacement vectors of wall signs in the horizontal plane exceed the accuracy of geodetic measurements and normative tolerances. Originality. Modeling of displacements of retaining walls in the conditions of recreational areas of the city is already underway, taking into account the analysis of the results of geodetic measurements of past years. Practical value. The data of the analysis of the results of geodetic measurements carried out in the geodetic densification networks of Kremenchuk indicate the presence of deformation processes and justify the need for their control through geodetic monitoring. The suggested models can be used as the comparative and combined analysis of future forecast changes based on previous and current results of measurements, which is a topic for another research.","PeriodicalId":19101,"journal":{"name":"Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu","volume":"14 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140410613","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":"Modeling pH changes and electrical conductivity in surface water as a result of mining activities","authors":"K. C. Aluwong, M. H. M. Hashim, S. Ismail, S. A. Shehu","doi":"10.33271/nvngu/2024-1/122","DOIUrl":"https://doi.org/10.33271/nvngu/2024-1/122","url":null,"abstract":"Purpose. To develop comprehensive models for predicting the pH and electrical conductivity of surface water in Maiganga coal mine and environs affected by mining activities. Methodology. The research utilizes a combination of in-situ measurement, laboratory analysis, modeling technique using Ansys Workbench and Linear Regression for predicting the content of pollutants. In-situ measurement/data collection in the upstream and downstream were carried out to evaluate the potential impact of mining activities on surface and ground water quality. Electrical conductivity and pH were measured on the samples that were collected using Oakton 5/6 pH meter and TDS/EC meter. Findings. According to the results, the regression statistics model of pH and electrical conductivity (EC) shows that the predicted values have a pH range of 4.7–7.05 and a mean pH value of 5.5. In contrast, while the EC ranges from 454.52 to 2,720.68 s/cm (EC) with a mean value of 905 µs/cm of the downstream flow which is completely dependent on the mine inlet (pH-in and EC-in). The findings show a direct correlation between surface water pH, electrical conductivity, and mining activities in the Maiganga coal mine area and their detrimental effects on the ecosystem and water quality. Originality. The results were obtained directly from the mine site during field visit and can be compared to data from active coal mine sites. Practical value. The detrimental effect of the results of mining activities can be controlled if monitoring sensors are introduced at mines’ effluent outlet to alert the mine management of possible danger in real time.","PeriodicalId":19101,"journal":{"name":"Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu","volume":"37 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140410943","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":"Modeling arithmetic systems of elliptic curve cryptography using Microsoft Excel VBA","authors":"I. Syamsuddin, S. Syafaruddin","doi":"10.33271/nvngu/2024-1/162","DOIUrl":"https://doi.org/10.33271/nvngu/2024-1/162","url":null,"abstract":"Purpose. This study aims to develop a new teaching module to illustrate the arithmetic systems of Elliptic Curve Cryptography, a powerful yet simple algorithm for information security, by exploring the capability of the Visual Basic Applications of Microsoft Excel in user friendly way. Methodology. The research is performed using research and development approach, which is divided into five steps utilizing VBA features of Microsoft Excel. It starts with modeling arithmetic in Microsoft Excel spreadsheet, then testing the validity through calculation and setup of the actual arithmetic of Elliptic Curve Cryptography using VBA Excel, before performing the test of the VBA application and finally visualizes the results in graphical mode. Findings. Novel teaching software based on of Microsoft Excel Visual Basic Applications is produced that is able to simulate arithmetic system behind Elliptic Curve Cryptography in an easy way for students. Originality. To the best of the authors’ knowledge, this is the first simulation based on Excel VBA to illustrate the arithmetic systems of Elliptic Curve Cryptography for teaching purposes. Practical value. In general, mastering cryptography will need a steep learning curve; however, using Microsoft Excel as a simulation platform will accelerate learning. The main practical value is the ease of Microsoft Excel, which will turn cryptography learning which was commonly very difficult for student to become easier and user friendly.","PeriodicalId":19101,"journal":{"name":"Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu","volume":"41 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140411559","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":"Improvement of the methodology for calculating the expected drilling speed with PDC chisels","authors":"B. Ratov, A. K. Sudakov, B. V. Fedorov, I. A. Ruslyakova-Kupriyanova, P. S. Sundetova","doi":"10.33271/nvngu/2024-1/026","DOIUrl":"https://doi.org/10.33271/nvngu/2024-1/026","url":null,"abstract":"Purpose. Determination of the dependence of the depth of penetration of the PDC cutter into the bottom hole rock, taking into account its geometric parameters and spatial placement in relation to the destroyed array. Methodology. The tasks were solved by a comprehensive research method, including analysis and generalization of literary and patent sources, conducting theoretical research, which consists in solving the theoretical problem of the impact of a superhard circular cutter on an elastically fragile mountain range, using computer and mathematical modeling methods. Findings. A simplified expression has been obtained that allows taking into account the features of the PDC cutter with sufficient accuracy for engineering calculations when determining the depth of its penetration into the bottom hole rock. A method is proposed for calculating the depth of fracture in one revolution of a diamond carbide cutter PDC into the rock of the bottom of the well. The patterns of destruction by the proposed diamond-hard-alloy PDC chisel of a rock mass at the bottom of the well from the parameters of the drilling regime and the hardness of the drilled rocks have been established. Originality. For the first time, the dependence has been obtained of the influence of the geometric parameters of the shape of a single diamond-carbide PDC cutter and its spatial placement in the body of the bit matrix on the magnitude of the technological parameters of drilling a well, and their effect on the nature of the destruction of the array PDC cutter. Practical value. A technique for determining the depth of penetration of a single PDC cutter is proposed, the use of which will allow predicting the mechanical speed, depending on the geological and technical conditions of drilling wells. And taking into account the abrasive properties of rocks, it is possible to reduce the wear of the bits, and therefore the amount of necessary rock-crushing tools for the entire volume of drilling operations during the construction of the well.","PeriodicalId":19101,"journal":{"name":"Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu","volume":"22 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140408919","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":"Method of controlling the volume of combustion products at different boiler loads","authors":"V. Kryvda, O. Brunetkin, K. Beglov, T. Markolenko, I. Lutsenko","doi":"10.33271/nvngu/2024-1/100","DOIUrl":"https://doi.org/10.33271/nvngu/2024-1/100","url":null,"abstract":"Purpose. Development of a method for controlling the volume of combustion products at different load of boiler equipment. Achieving the objective may allow controlling the flue gas temperature and, consequently, the efficiency to increase it. Methodology. Control of the flue gas volume value on the basis of determining the appropriate composition of the fuel gas mixture. Findings. The effect of flue gas temperature increase at use of fuel gases of lower calorific value and increase in ballast gases quantity is revealed. The latter can be the air used as an oxidising agent at its considerable excess. The mechanism of such an effect due to the increase in the quantity and velocity of flue gases is suggested. A parameter determining the volume of flue gases produced per unit calorific value of various fuel gases is proposed. On the basis of this parameter the method for calculating the composition of the mixture of different gases to ensure the constancy of the flue gas volume at variable load is proposed Originality. On the example of the results of verification thermal calculation the change in flue gas temperature and efficiency value is considered. The non-standard character of their change is revealed. In contrast to the case of using fuel gas of constant composition with increasing load, the temperature of flue gases remained close to constant, and the value of efficiency increased. Practical value. The obtained results indicate the possibility of controlling the flue gas temperature and boiler efficiency at a given load. This allows one, unlike the case of using fuel gas of constant composition, to increase the efficiency exactly at maximum load avoiding getting into the condensate mode at minimum load. There is a possibility to save fossil gas and, consequently, to reduce the greenhouse share in CO2 emissions.","PeriodicalId":19101,"journal":{"name":"Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140415334","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":"Stochastic models of work and rest schedules","authors":"A. Bochkovskyi","doi":"10.33271/nvngu/2024-1/114","DOIUrl":"https://doi.org/10.33271/nvngu/2024-1/114","url":null,"abstract":"Purpose. To develop stochastic models for determining the duration of work and rest schedules that ensure protection of workers from occupational hazards and a high level of labor productivity during a work shift. Methodology. Analysis of scientific literature was applied to determine the purpose and tasks of the research; methods of formalization – to describe the characteristics, dynamics and states of random processes of accumulation and elimination of the consequences of the negative impact of harmful production factors occurring in an worker within the work and rest schedules; methods of semi-Markov processes theory, theories of reliability and recovery – to build stochastic models of work and rest schedules, determine the conditions and probability of a stable mode of their operation. Findings. Stochastic models were developed to determine the duration of work schedules, at the end of which the level of accumulation of the consequences of the negative impact of harmful production factors in the worker will not exceed the set maximum permissible values with a high probability. And such durations of rest schedules, at the end of which this level will be equal to zero (also with a high probability). The condition for ensuring the stable operation of these schedules throughout the entire period of work experience at the workplace was determined by the author. Originality. For the first time an approach to the development of work and rest schedules at workplaces is proposed, which, contrary to others, is based on determining the probabilities of the levels of accumulation of the consequences of the negative impact of harmful production factors in the worker at the end of these schedules, given the actual random and dynamic characteristics of such impact. This, in turn, allows ensuring the protection of the worker both from accidents caused by the fatigue and from professional illness. Practical value. The proposed approach allows increasing the economic efficiency of the enterprise by ensuring a high level of labor productivity, which is achieved by simultaneous development of the maximum possible duration of work and the minimum possible duration of rest schedules, which exclude the worker’s development and occurrence of fatigue and professional illness with a high probability.","PeriodicalId":19101,"journal":{"name":"Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu","volume":"20 3","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140411061","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":"An overview of hydrogen production via reforming from natural gas","authors":"D. Le, Nguyen The Dzung","doi":"10.33271/nvngu/2024-1/092","DOIUrl":"https://doi.org/10.33271/nvngu/2024-1/092","url":null,"abstract":"Purpose. To provide an extensive analysis of hydrogen production and the major benefits as well as challenges in the hydrogen production from natural gas. Methodology. The systematic review approach was used in this study. The first stage in a holistic evaluation is to find related significant works and specific concepts, and then apply them to search phrases and syntax. A thorough search is implemented in the Web of Science, Google Scholar, Science Direct, and Scopus databases in the English language. Moreover, the publication time of the papers is also limited in the period from 2010 to September 2023. Findings. The literature review revealed that natural gas reforming is the most prevalent technique for producing hydrogen. The obtained results also showed that the approach based on automatic thermal reforming is less common than the one that uses natural gas to create hydrogen by steam reforming. Additionally, natural gas steam reforming has the most harmful environmental influences with regard to abiotic degradation, potential global warming, and other influence types. Originality. This analysis offers an in-depth overview of how hydrogen is produced from natural gas as well as the benefits and limitations of the reforming method for producing hydrogen. Practical value. From the literature review, it was found that the current preferred method for creating hydrogen is steam natural gas reforming. In addition, this review provides a comprehensive and useful resource for study, scientific advancement, and advancement in the disciplines of creating hydrogen.","PeriodicalId":19101,"journal":{"name":"Naukovyi Visnyk Natsionalnoho Hirnychoho Universytetu","volume":"700 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140416996","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}