Pub Date : 2019-10-01DOI: 10.1109/iestec46403.2019.00114
J. C. Castro, Martín Zhindón Mora, P. Neira
In Ecuador, the need to introduce electronic money has been seen as a way to lighten the use of cash and renew the current financial system; however, this implementation has not yielded the desired result and instead has caused much more distrust on the part of Ecuadorians regarding the management of funds by the State; that is why this research show the use of a proprietary cryptocurrency as a new means of payment, in the Ecuadorian economy, leaving aside the current banking system and ensuring that any person, regardless of their income, can access this new financial transactional network . In order to adapt this system in the best way and according to the reality of the country, the theory behind the blockchain and, of course, the cryptocurrency has been studied, the legal environment currently in force in Ecuador, and it has been taken as a reference to Latin American countries that have already introduced these new means of payment in their financial system, analyzing their form of implementation, performance characteristics and results obtained in their economy.
{"title":"Blockchain as Virtual Currency in Ecuador","authors":"J. C. Castro, Martín Zhindón Mora, P. Neira","doi":"10.1109/iestec46403.2019.00114","DOIUrl":"https://doi.org/10.1109/iestec46403.2019.00114","url":null,"abstract":"In Ecuador, the need to introduce electronic money has been seen as a way to lighten the use of cash and renew the current financial system; however, this implementation has not yielded the desired result and instead has caused much more distrust on the part of Ecuadorians regarding the management of funds by the State; that is why this research show the use of a proprietary cryptocurrency as a new means of payment, in the Ecuadorian economy, leaving aside the current banking system and ensuring that any person, regardless of their income, can access this new financial transactional network . In order to adapt this system in the best way and according to the reality of the country, the theory behind the blockchain and, of course, the cryptocurrency has been studied, the legal environment currently in force in Ecuador, and it has been taken as a reference to Latin American countries that have already introduced these new means of payment in their financial system, analyzing their form of implementation, performance characteristics and results obtained in their economy.","PeriodicalId":388062,"journal":{"name":"2019 7th International Engineering, Sciences and Technology Conference (IESTEC)","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134252170","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}
Pub Date : 2019-10-01DOI: 10.1109/IESTEC46403.2019.00-73
C. Hernández, J. Olmos, F. Vergara, Astrid Loré, L. Arza, Cenobio Cárdenas, Ildemán Abrego, Miguel Angel Hernández Espinosa
It presents the results of the microstructural and morphological characterization of a natural Zeolite from the province of Chiriqui, Panama. By X-ray diffraction and Rietveld refinement, the presence of Zeolite Natural Analcima is determined, but with other related minerals, from the point of view of their geological formation, such as: Albite, Diopside and Sanidine mainly. The use of the Fourier Transform Infrared Spectroscopy (FTIR) technique confirms the presence of the Analcima. Combining thermal treatments to the Zeolite and studying the variation of its FTIR spectra, it is inferred that Analcima (and its other constituents) is stable up to 600 °C, since its absorption spectrum does not change significantly, while at higher temperatures absorption bands related crystalline water bonds, progressively decrease up to 1000 °C, where they disappear. The evaluation of the Scanning Electron Microscopy Analcime reveals a mixed morphology, consisting of structures in the form of columns, sheets and polygonal particles, as well as cavities of approximately 5 micrometers in diameter. A particular detail is that with the heat treatment of the Zeolite up to 1000 ° C, the morphology does not change significantly, which suggests the microstructural stability of the Zeolite.
{"title":"Microstructural and Morphological Properties of an Analcima Natural Zeolite of Interest for Environmental Applications","authors":"C. Hernández, J. Olmos, F. Vergara, Astrid Loré, L. Arza, Cenobio Cárdenas, Ildemán Abrego, Miguel Angel Hernández Espinosa","doi":"10.1109/IESTEC46403.2019.00-73","DOIUrl":"https://doi.org/10.1109/IESTEC46403.2019.00-73","url":null,"abstract":"It presents the results of the microstructural and morphological characterization of a natural Zeolite from the province of Chiriqui, Panama. By X-ray diffraction and Rietveld refinement, the presence of Zeolite Natural Analcima is determined, but with other related minerals, from the point of view of their geological formation, such as: Albite, Diopside and Sanidine mainly. The use of the Fourier Transform Infrared Spectroscopy (FTIR) technique confirms the presence of the Analcima. Combining thermal treatments to the Zeolite and studying the variation of its FTIR spectra, it is inferred that Analcima (and its other constituents) is stable up to 600 °C, since its absorption spectrum does not change significantly, while at higher temperatures absorption bands related crystalline water bonds, progressively decrease up to 1000 °C, where they disappear. The evaluation of the Scanning Electron Microscopy Analcime reveals a mixed morphology, consisting of structures in the form of columns, sheets and polygonal particles, as well as cavities of approximately 5 micrometers in diameter. A particular detail is that with the heat treatment of the Zeolite up to 1000 ° C, the morphology does not change significantly, which suggests the microstructural stability of the Zeolite.","PeriodicalId":388062,"journal":{"name":"2019 7th International Engineering, Sciences and Technology Conference (IESTEC)","volume":"227 13","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133847859","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}
Pub Date : 2019-10-01DOI: 10.1109/IESTEC46403.2019.00-74
Jesús Araúz, D. Mora, M. C. Austin
With the purpose of giving recommendations about building construction techniques in Panama to reduce the energy consumption, this article presents the results obtained from thermal dynamic simulations carried out for a generic building inspired on the building structure implemented in the Technological University of Panama Campus. This before by considering its geographical location, meteorological data, and composition of walls, floors, ceilings and windows. This simulation aims to study the thermal behavior of the building depending merely on its envelope features, specifically, on the variation of "window to wall" ratio (WWR) and on the addition of internal and external insulation layers on the external walls. Results showed that one of the most relevant features of the envelope is the WWR, which improved the indoor conditions significantly if minimized. However, adding insulation layer does not improve the building indoor conditions.
{"title":"Impact of the Envelope Layout in the Thermal Behavior of Buildings in Panama: A Numerical Study","authors":"Jesús Araúz, D. Mora, M. C. Austin","doi":"10.1109/IESTEC46403.2019.00-74","DOIUrl":"https://doi.org/10.1109/IESTEC46403.2019.00-74","url":null,"abstract":"With the purpose of giving recommendations about building construction techniques in Panama to reduce the energy consumption, this article presents the results obtained from thermal dynamic simulations carried out for a generic building inspired on the building structure implemented in the Technological University of Panama Campus. This before by considering its geographical location, meteorological data, and composition of walls, floors, ceilings and windows. This simulation aims to study the thermal behavior of the building depending merely on its envelope features, specifically, on the variation of \"window to wall\" ratio (WWR) and on the addition of internal and external insulation layers on the external walls. Results showed that one of the most relevant features of the envelope is the WWR, which improved the indoor conditions significantly if minimized. However, adding insulation layer does not improve the building indoor conditions.","PeriodicalId":388062,"journal":{"name":"2019 7th International Engineering, Sciences and Technology Conference (IESTEC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130245072","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}
Pub Date : 2019-10-01DOI: 10.1109/IESTEC46403.2019.00-60
B. Fernández, Norma L. Miller
During 2017 and 2018, the Precalculus course at the Technological University of Panama was offered via an intelligent tutoring system (ITS). Analysis of the results show that student interaction with the ITS learning modules contributes to the levelling of knowledge and to improved performance in mathematics. As a by-product of this implementation, a proposal called "Remedial Action Program" (Spanish acronym, PAR), is presented in this article, the purpose of which is to take advantage of STI's to level students' mathematical knowledge, thereby improving their chances to be admitted to, and retained in, the UTP. This proposal is structured around three programs for students with different mathematics profiles.
{"title":"Proposal to Implement the Precalculus and Basic Mathematics Courses Using an Intelligent Tutoring System","authors":"B. Fernández, Norma L. Miller","doi":"10.1109/IESTEC46403.2019.00-60","DOIUrl":"https://doi.org/10.1109/IESTEC46403.2019.00-60","url":null,"abstract":"During 2017 and 2018, the Precalculus course at the Technological University of Panama was offered via an intelligent tutoring system (ITS). Analysis of the results show that student interaction with the ITS learning modules contributes to the levelling of knowledge and to improved performance in mathematics. As a by-product of this implementation, a proposal called \"Remedial Action Program\" (Spanish acronym, PAR), is presented in this article, the purpose of which is to take advantage of STI's to level students' mathematical knowledge, thereby improving their chances to be admitted to, and retained in, the UTP. This proposal is structured around three programs for students with different mathematics profiles.","PeriodicalId":388062,"journal":{"name":"2019 7th International Engineering, Sciences and Technology Conference (IESTEC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130495554","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}
Pub Date : 2019-10-01DOI: 10.1109/IESTEC46403.2019.00018
Ernesto Patricio Feijoo Calle, Cristian Andrés Flores Vera, B. Guevara
In this work the concept of "Granulometric Area" is introduced, which allows to establish a relationship between the granulometric curves and the compressive strength of the rock. After taking a series of rock samples, preparing them and executing crushing processes and evaluating the compressive strength of said materials, a relationship between these two parameters can be established and thus avoid permanently sending samples to the laboratory, allowing a significant savings in time and money. This relationship is presented in a graphic way, and easy to interpret in each study area, establishing the parameters for the identification of the rock treated and studied.
{"title":"The Concept of the Granulometric Area and Its Relation with the Resistance to the Simple Compression of Rocks","authors":"Ernesto Patricio Feijoo Calle, Cristian Andrés Flores Vera, B. Guevara","doi":"10.1109/IESTEC46403.2019.00018","DOIUrl":"https://doi.org/10.1109/IESTEC46403.2019.00018","url":null,"abstract":"In this work the concept of \"Granulometric Area\" is introduced, which allows to establish a relationship between the granulometric curves and the compressive strength of the rock. After taking a series of rock samples, preparing them and executing crushing processes and evaluating the compressive strength of said materials, a relationship between these two parameters can be established and thus avoid permanently sending samples to the laboratory, allowing a significant savings in time and money. This relationship is presented in a graphic way, and easy to interpret in each study area, establishing the parameters for the identification of the rock treated and studied.","PeriodicalId":388062,"journal":{"name":"2019 7th International Engineering, Sciences and Technology Conference (IESTEC)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128907260","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}
Pub Date : 2019-10-01DOI: 10.1109/IESTEC46403.2019.00-67
L. Paramo-Aguilera, Zoraya Pérez-Zelaya
This paper aims to determine the contribution of biotechnology to the graduate index in Chemical Engineering at the National University of Engineering and to analyze whether the number of subjects related to biotechnology in the current program of the Chemical Engineer, is sufficient in relation to the number of graduates obtained as an indirect measure of the demands of the student sector and the community of potential employers, considering that in most cases theses are chosen by students in relation to problems in the productive sector. For the realization of this work it was first defined a period of study between 1990 and 2018, gathering information on these carried out in that period, to finally determine in which areas of biotechnology these theses were being carried out and thus determine whether the career program was meeting the students' knowledge demands for the performance of these jobs. The results showed that, out of 322 thesis studies carried out, 59 of these have been on topics related to biotechnology (18.32 %) and have been carried out in areas of industrial biotechnology, environmental and bioengineering. This work showed the urgent need to make changes to the curriculum that will allow to equip the graduates with the biological tools they need to fulfill the expressed in the profile of the graduate of Chemical Engineering.
{"title":"Biotechnology and Development in Nicaragua: How Chemical Engineering Has Contributed to the Impulse for Biotechnology and Vice Versa","authors":"L. Paramo-Aguilera, Zoraya Pérez-Zelaya","doi":"10.1109/IESTEC46403.2019.00-67","DOIUrl":"https://doi.org/10.1109/IESTEC46403.2019.00-67","url":null,"abstract":"This paper aims to determine the contribution of biotechnology to the graduate index in Chemical Engineering at the National University of Engineering and to analyze whether the number of subjects related to biotechnology in the current program of the Chemical Engineer, is sufficient in relation to the number of graduates obtained as an indirect measure of the demands of the student sector and the community of potential employers, considering that in most cases theses are chosen by students in relation to problems in the productive sector. For the realization of this work it was first defined a period of study between 1990 and 2018, gathering information on these carried out in that period, to finally determine in which areas of biotechnology these theses were being carried out and thus determine whether the career program was meeting the students' knowledge demands for the performance of these jobs. The results showed that, out of 322 thesis studies carried out, 59 of these have been on topics related to biotechnology (18.32 %) and have been carried out in areas of industrial biotechnology, environmental and bioengineering. This work showed the urgent need to make changes to the curriculum that will allow to equip the graduates with the biological tools they need to fulfill the expressed in the profile of the graduate of Chemical Engineering.","PeriodicalId":388062,"journal":{"name":"2019 7th International Engineering, Sciences and Technology Conference (IESTEC)","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128841881","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}
Pub Date : 2019-10-01DOI: 10.1109/IESTEC46403.2019.00077
Milena Gómez-Cedeño, D. Ng
Panama is considered as a service country, in which the Panama Canal contributes with more than $1.5 million per year to the state. Known as a logistic hub, Panama's economy depends on service industries. This happens in most of the countries around the world, the service sector represents more than the 50% of the GDP, increasing the importance of an efficient supply chain mangament for service industries. However, to adapt the supply chain management to service companies it most be understanded all the facts around services and the possibility of adapting an existing supply chain model. On the other hand, Servitization is a term referring to the integration of services to a manufacturing company which increased the importance of managing services. This strategy implies changes in the supply chain of manufacturing companies that can be used as a foundation for the service supply chain. Having two different terms that converge in the servitized supply chain, leads the research to the comparison in a statistically way of "servitization" and "service supply chain". The comparison of both topics is done with a bibliometric analysis, using maps done with the Vosviewer software. The bibliometric maps are based on the results of a systematic search, obtaining 211 articles for servitization and 72 for the service supply chain. At the end of this paper a discussion of the results is given.
{"title":"Research Mappings: Service Supply Chain versus Servitization","authors":"Milena Gómez-Cedeño, D. Ng","doi":"10.1109/IESTEC46403.2019.00077","DOIUrl":"https://doi.org/10.1109/IESTEC46403.2019.00077","url":null,"abstract":"Panama is considered as a service country, in which the Panama Canal contributes with more than $1.5 million per year to the state. Known as a logistic hub, Panama's economy depends on service industries. This happens in most of the countries around the world, the service sector represents more than the 50% of the GDP, increasing the importance of an efficient supply chain mangament for service industries. However, to adapt the supply chain management to service companies it most be understanded all the facts around services and the possibility of adapting an existing supply chain model. On the other hand, Servitization is a term referring to the integration of services to a manufacturing company which increased the importance of managing services. This strategy implies changes in the supply chain of manufacturing companies that can be used as a foundation for the service supply chain. Having two different terms that converge in the servitized supply chain, leads the research to the comparison in a statistically way of \"servitization\" and \"service supply chain\". The comparison of both topics is done with a bibliometric analysis, using maps done with the Vosviewer software. The bibliometric maps are based on the results of a systematic search, obtaining 211 articles for servitization and 72 for the service supply chain. At the end of this paper a discussion of the results is given.","PeriodicalId":388062,"journal":{"name":"2019 7th International Engineering, Sciences and Technology Conference (IESTEC)","volume":"293 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115215265","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}
Pub Date : 2019-10-01DOI: 10.1109/IESTEC46403.2019.00-65
L. E. Jardón-Pérez, C. González-Rivera, M. Ramírez-Argáez
One of the most important parameters to define the performance of the steelmaking ladle furnace is the mixing time. The most popular method to determine the mixing time is through an immersed probe to measure changes in conductivity or pH in a single point. An alternative method to measure mixing time is through the experimental technique called Planar Laser-Induced Fluorescence (PLIF). This technique measures concentrations changes of a fluorescent tracer in a whole plane of the system in a non-intrusive way and it has not been reported before in the literature to measure mixing times in these systems. In this work, details on the use of PLIF in physical models of ladle furnaces are studied, such as the effect of the model scale and the effect of the kind of water employed to do the measurements.
{"title":"Effect of Model Size and Water Chemical Composition on Mixing Time Measurements Using PLIF in a Gas-Stirred Ladle","authors":"L. E. Jardón-Pérez, C. González-Rivera, M. Ramírez-Argáez","doi":"10.1109/IESTEC46403.2019.00-65","DOIUrl":"https://doi.org/10.1109/IESTEC46403.2019.00-65","url":null,"abstract":"One of the most important parameters to define the performance of the steelmaking ladle furnace is the mixing time. The most popular method to determine the mixing time is through an immersed probe to measure changes in conductivity or pH in a single point. An alternative method to measure mixing time is through the experimental technique called Planar Laser-Induced Fluorescence (PLIF). This technique measures concentrations changes of a fluorescent tracer in a whole plane of the system in a non-intrusive way and it has not been reported before in the literature to measure mixing times in these systems. In this work, details on the use of PLIF in physical models of ladle furnaces are studied, such as the effect of the model scale and the effect of the kind of water employed to do the measurements.","PeriodicalId":388062,"journal":{"name":"2019 7th International Engineering, Sciences and Technology Conference (IESTEC)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127720439","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}
Pub Date : 2019-10-01DOI: 10.1109/IESTEC46403.2019.00093
Andres Leonardo Puentes, M. Roa
Currently the function of collection of solid household waste presents considerable drawbacks, due to the deterioration of the state of the roads and the poor development of the Land Management Plan in the city of Villavicencio, especially in the neighborhoods of La Ceiba, Cedritos, La Desmotadora and Seis de Abril, where it is difficult for the collector vehicle to pass, causing a considerable increase in exercise time and dissatisfaction among the inhabitants of the sector. A modification was proposed in the micro route of collection that allowed to optimize the time of the activities making use of strategic points that have containers, where all the solid residues must be deposited, diminishing the distance covered by the vehicle. As a result of this optimization, of 8.86% of the costs reflected in $ 27,603,330 pesos per year.
目前，由于比亚维森西奥市的道路状况恶化和土地管理计划的发展不佳，特别是在La Ceiba、Cedritos、La Desmotadora和Seis de Abril等社区，收集固体家庭废物的功能存在相当大的缺陷，收集车辆难以通过，导致该地区居民的运动时间大大增加和不满。在收集的微路线上提出了一个修改，允许优化活动的时间，利用具有容器的战略点，所有固体残留物必须存放在那里，减少车辆覆盖的距离。由于这一优化，8.86%的成本反映在每年$ 27,603,330比索。
{"title":"Proposal for the Optimization of the Household Solid Waste Recollection System Case Study: Micro Ruta (Villavicencio, Colombia)","authors":"Andres Leonardo Puentes, M. Roa","doi":"10.1109/IESTEC46403.2019.00093","DOIUrl":"https://doi.org/10.1109/IESTEC46403.2019.00093","url":null,"abstract":"Currently the function of collection of solid household waste presents considerable drawbacks, due to the deterioration of the state of the roads and the poor development of the Land Management Plan in the city of Villavicencio, especially in the neighborhoods of La Ceiba, Cedritos, La Desmotadora and Seis de Abril, where it is difficult for the collector vehicle to pass, causing a considerable increase in exercise time and dissatisfaction among the inhabitants of the sector. A modification was proposed in the micro route of collection that allowed to optimize the time of the activities making use of strategic points that have containers, where all the solid residues must be deposited, diminishing the distance covered by the vehicle. As a result of this optimization, of 8.86% of the costs reflected in $ 27,603,330 pesos per year.","PeriodicalId":388062,"journal":{"name":"2019 7th International Engineering, Sciences and Technology Conference (IESTEC)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125445200","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}
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