Pub Date : 2022-11-09DOI: 10.1109/concapan48024.2022.9997724
C. Ospina
This paper documents the consequences that occur in the absence of a diagnosis in Medium Voltage networks and cables in renewable energy applications (wind, photovoltaic), the lack or “savings” in prevention can lead to large economic losses and great disappointment in network users. In a scenario of digitalization, decarbonization and decentralization, the reliability and security of energy systems require prevention and diagnosis tools that allow achieving greater performance in the face of current challenges. Losses in power generation and losses due to repairs (corrective maintenance) are enormous and could directly and constantly affect the continuity of electrical systems.
{"title":"Reliability in Medium Voltage Distribution Systems in Renewable Energy Applications","authors":"C. Ospina","doi":"10.1109/concapan48024.2022.9997724","DOIUrl":"https://doi.org/10.1109/concapan48024.2022.9997724","url":null,"abstract":"This paper documents the consequences that occur in the absence of a diagnosis in Medium Voltage networks and cables in renewable energy applications (wind, photovoltaic), the lack or “savings” in prevention can lead to large economic losses and great disappointment in network users. In a scenario of digitalization, decarbonization and decentralization, the reliability and security of energy systems require prevention and diagnosis tools that allow achieving greater performance in the face of current challenges. Losses in power generation and losses due to repairs (corrective maintenance) are enormous and could directly and constantly affect the continuity of electrical systems.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122629479","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997670
F. Osorio, R. Barazarte
This paper explains the automation process of a deliverability study performed using a 2000-bus synthetic grid on the footprint of Texas [1]. The project algorithm aims to streamline the study process using PTDF analysis and Python scripting automation. The proposed algorithm will simplify the re-dispatch process of available generation during a large-scale N-1 simulation.
{"title":"Generation Re-dispatch and Deliverability Analysis using Power Transfer Distribution Factors","authors":"F. Osorio, R. Barazarte","doi":"10.1109/CONCAPAN48024.2022.9997670","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997670","url":null,"abstract":"This paper explains the automation process of a deliverability study performed using a 2000-bus synthetic grid on the footprint of Texas [1]. The project algorithm aims to streamline the study process using PTDF analysis and Python scripting automation. The proposed algorithm will simplify the re-dispatch process of available generation during a large-scale N-1 simulation.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125416674","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997694
Álvaro Zavala, Leonel Maye
Currently in El Salvador, efforts are being made to implement the digital signature and as part of this technology, a Public Key Infrastructure (PKI) is required, which must validate Certificate Authorities (CA). For a CA, it is necessary to implement the software that allows it to manage digital certificates and perform security procedures for the execution of cryptographic operations, such as encryption, digital signatures, and non-repudiation of electronic transactions. The present work makes a proposal for a digital certificate management system according to the Digital Signature Law of El Salvador and secure cryptography standards. Additionally, a security discussion is accomplished.
{"title":"Application to manage digital certificates as a Certificate Authority (CA) according to the Digital Signature Law of El Salvador","authors":"Álvaro Zavala, Leonel Maye","doi":"10.1109/CONCAPAN48024.2022.9997694","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997694","url":null,"abstract":"Currently in El Salvador, efforts are being made to implement the digital signature and as part of this technology, a Public Key Infrastructure (PKI) is required, which must validate Certificate Authorities (CA). For a CA, it is necessary to implement the software that allows it to manage digital certificates and perform security procedures for the execution of cryptographic operations, such as encryption, digital signatures, and non-repudiation of electronic transactions. The present work makes a proposal for a digital certificate management system according to the Digital Signature Law of El Salvador and secure cryptography standards. Additionally, a security discussion is accomplished.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130967239","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997636
Jesús O. Ponce, C. Gutiérrez, F. Castillo-Soria
This paper presents an experimental analysis of the depolarization effects that multipath propagation produces on radio-frequency (RF) signals. The analysis is based on the results of a measurement campaign conducted in a suburban scenario in the city of San Luis Potosí, México. Such a campaign collected empirical data of the instantaneous power and Doppler power spectrum (DPS) of an infrastructure-to-vehicle (I2V) channel at 2.45 GHz. The measured data were used to compute three different cross-polarization discriminators (XPD). One of such discriminators has been widely used in the literature to assess the power ratio between co-polarized and cross-polarized signals. The other two discriminators, which are based on the Doppler shift ratio and Doppler spread ratio, are introduced in this paper as new figures of merit to measure the impact of multipath depolarization on the frequency-dispersion characteristics of vehicular RF channels. The results demonstrate that the cross-polarized multipath components of the I2V channel response produce a Doppler frequency dispersion similar to that of the co-polarized components.
{"title":"Experimental Analysis of Depolarization Effects of Infrastructure-to-Vehicle Radio Channels","authors":"Jesús O. Ponce, C. Gutiérrez, F. Castillo-Soria","doi":"10.1109/CONCAPAN48024.2022.9997636","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997636","url":null,"abstract":"This paper presents an experimental analysis of the depolarization effects that multipath propagation produces on radio-frequency (RF) signals. The analysis is based on the results of a measurement campaign conducted in a suburban scenario in the city of San Luis Potosí, México. Such a campaign collected empirical data of the instantaneous power and Doppler power spectrum (DPS) of an infrastructure-to-vehicle (I2V) channel at 2.45 GHz. The measured data were used to compute three different cross-polarization discriminators (XPD). One of such discriminators has been widely used in the literature to assess the power ratio between co-polarized and cross-polarized signals. The other two discriminators, which are based on the Doppler shift ratio and Doppler spread ratio, are introduced in this paper as new figures of merit to measure the impact of multipath depolarization on the frequency-dispersion characteristics of vehicular RF channels. The results demonstrate that the cross-polarized multipath components of the I2V channel response produce a Doppler frequency dispersion similar to that of the co-polarized components.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128856579","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997796
R. Hernandez, Benjamin Hancock, M. Salmeron
This work is a compilation of lessons learned from the analysis of power transformer failures occurred in North and South America based on data collected by Doble Engineering Company over the last ten years. The paper includes annual failure rates and related reports based on voltage rating, failure cause, manufacturing decade, age distribution, among other parameters.
{"title":"Lessons Learned from Analysis of Power Transformer Failure Rates","authors":"R. Hernandez, Benjamin Hancock, M. Salmeron","doi":"10.1109/CONCAPAN48024.2022.9997796","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997796","url":null,"abstract":"This work is a compilation of lessons learned from the analysis of power transformer failures occurred in North and South America based on data collected by Doble Engineering Company over the last ten years. The paper includes annual failure rates and related reports based on voltage rating, failure cause, manufacturing decade, age distribution, among other parameters.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"06 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127252564","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997707
Jaiber Evelio Cardona Aristizábal, J. Gutiérrez
In order to teach automation and control, they must organize laboratory practices that complement the theoretical items. In this sense, automation and control laboratories are expensive and they have reduced access hours. In this work, we show a remote laboratory that is being used by students of the Electronic Engineering career at the University of Quindío. The remote laboratory permits the access to three systems: a neumatic levitator, a 2D robot, and a fly-cutting system. The remote laboratory is offered twenty fourth hours a day, seven days a week. The students can schedule dates and hours for the development of practices, including at night, weekends, or holydays.
{"title":"A remote laboratory platform for teaching automation and control","authors":"Jaiber Evelio Cardona Aristizábal, J. Gutiérrez","doi":"10.1109/CONCAPAN48024.2022.9997707","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997707","url":null,"abstract":"In order to teach automation and control, they must organize laboratory practices that complement the theoretical items. In this sense, automation and control laboratories are expensive and they have reduced access hours. In this work, we show a remote laboratory that is being used by students of the Electronic Engineering career at the University of Quindío. The remote laboratory permits the access to three systems: a neumatic levitator, a 2D robot, and a fly-cutting system. The remote laboratory is offered twenty fourth hours a day, seven days a week. The students can schedule dates and hours for the development of practices, including at night, weekends, or holydays.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128196255","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997741
Andony Reyes Sánchez, Sandro Chavarría Condega
This document presents the functionality of a Simulator Prototype that allows load flows studies, and optimal power flows studies to be carried out in alternating current power systems. The program was developed using the C# and C++ languages with Microsoft Visual Studio. The Newton-Raphson method is used to solve the load flow problem, and a Non-Interior Point method is used to solve the optimal power flow problem. Performance tests were carried out on the prototype from multiple cases of power systems, and satisfactory results were obtained.
{"title":"Study of Load Flows and Optimal Power Flows using a simulator prototype","authors":"Andony Reyes Sánchez, Sandro Chavarría Condega","doi":"10.1109/CONCAPAN48024.2022.9997741","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997741","url":null,"abstract":"This document presents the functionality of a Simulator Prototype that allows load flows studies, and optimal power flows studies to be carried out in alternating current power systems. The program was developed using the C# and C++ languages with Microsoft Visual Studio. The Newton-Raphson method is used to solve the load flow problem, and a Non-Interior Point method is used to solve the optimal power flow problem. Performance tests were carried out on the prototype from multiple cases of power systems, and satisfactory results were obtained.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129969777","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997599
Omar Rivera-Caballero, Alberto Cogley, M. Rios, Jenifer González, Carlos Boya-Lara
In recent years, the use of energy storage systems to provide flexibility to renewable technologies has been identified as a key point to increase the effectiveness of clean technologies and reduce greenhouse gas emissions. In particular, the introduction of energy storage systems with batteries to supply consumers with self-consumption photovoltaic installations has proven to be a viable solution that can present additional benefits. One of these additional benefits can be a positive effect on the distribution network. In this paper, we analyze the potential impacts on the demand side that the integration of battery systems would have on distribution networks with photovoltaic penetration, specifically, the ability to perform peak shaving through battery systems is considered. To validate the potential of the battery system, a distribution system was simulated with real data, and a control strategy was also used to perform the peak shaving task. The results of the simulations indicate that the integration of battery systems can considerably improve peak load reduction by up to 0.2 MW in each phase on the distribution system.
{"title":"Potential Impacts of Demand-side Battery Storage on Distribution Networks with PV Penetration","authors":"Omar Rivera-Caballero, Alberto Cogley, M. Rios, Jenifer González, Carlos Boya-Lara","doi":"10.1109/CONCAPAN48024.2022.9997599","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997599","url":null,"abstract":"In recent years, the use of energy storage systems to provide flexibility to renewable technologies has been identified as a key point to increase the effectiveness of clean technologies and reduce greenhouse gas emissions. In particular, the introduction of energy storage systems with batteries to supply consumers with self-consumption photovoltaic installations has proven to be a viable solution that can present additional benefits. One of these additional benefits can be a positive effect on the distribution network. In this paper, we analyze the potential impacts on the demand side that the integration of battery systems would have on distribution networks with photovoltaic penetration, specifically, the ability to perform peak shaving through battery systems is considered. To validate the potential of the battery system, a distribution system was simulated with real data, and a control strategy was also used to perform the peak shaving task. The results of the simulations indicate that the integration of battery systems can considerably improve peak load reduction by up to 0.2 MW in each phase on the distribution system.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128554313","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997621
A. Suazo
The problem studied was centered on the people in Tegucigalpa, who are currently buying reprocessed products that contains large amounts of carbohydrates and sugars. The general objective is to design a list of dairy products and wheat flours that complies with the dietary restrictions for a person with diabetes, through operational research tools. The specific objectives are to design a mathematical model to select the products, define a minimum budget, identify the product’s quality and price ratio, as well as validating the results with experts. This research has a quantitative approach with a correlational scope, containing a sample of 52 dairy products and wheat flours. As a result, 7 equations where defined. Differences in cost were identified based on the week of the month as well as the gender of the participants. For the first week of the month the male participant needs a minimum budget of L.213.90, while the female participant needs L.196.60. The rest of the weeks in the month require a lower budget, with a minimum of L.114.00 per week. Dairy products are the same for both genders, which are Delactomy semi-fat lactose-free milk, Leyde’s pasteurized cream, Lactolac’s cream cheese. Wheat products for men: Suli bread, Monarca’s flour tortillas, and Bimbo’s double fiber toast. Wheat products for women: Artisan’s bread, Monarca’s flour tortillas, and Hawit’s hot dog bread. The proposed mathematical model is intended to serve as a basis for the design of other engineering tools that help diabetic consumers to choose their daily products.
{"title":"Allocation of Dairy Products and Wheat Flours through Mathematical Modeling in Tegucigalpa","authors":"A. Suazo","doi":"10.1109/CONCAPAN48024.2022.9997621","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997621","url":null,"abstract":"The problem studied was centered on the people in Tegucigalpa, who are currently buying reprocessed products that contains large amounts of carbohydrates and sugars. The general objective is to design a list of dairy products and wheat flours that complies with the dietary restrictions for a person with diabetes, through operational research tools. The specific objectives are to design a mathematical model to select the products, define a minimum budget, identify the product’s quality and price ratio, as well as validating the results with experts. This research has a quantitative approach with a correlational scope, containing a sample of 52 dairy products and wheat flours. As a result, 7 equations where defined. Differences in cost were identified based on the week of the month as well as the gender of the participants. For the first week of the month the male participant needs a minimum budget of L.213.90, while the female participant needs L.196.60. The rest of the weeks in the month require a lower budget, with a minimum of L.114.00 per week. Dairy products are the same for both genders, which are Delactomy semi-fat lactose-free milk, Leyde’s pasteurized cream, Lactolac’s cream cheese. Wheat products for men: Suli bread, Monarca’s flour tortillas, and Bimbo’s double fiber toast. Wheat products for women: Artisan’s bread, Monarca’s flour tortillas, and Hawit’s hot dog bread. The proposed mathematical model is intended to serve as a basis for the design of other engineering tools that help diabetic consumers to choose their daily products.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120848897","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 : 2022-11-09DOI: 10.1109/CONCAPAN48024.2022.9997696
J. P. S. H. Moreno, Ana. R. Fischer-Meza, Alfredo. Mejía-Torres, Miguel A. Arellano-Serrano, P. Rodrigo, H. E. Gilardi-Velázquez
Atmospheric research impacts various sectors such as commercial aviation activities, maritime transport, climatological analysis, and space research, among others. Knowing the atmospheric density of the ionosphere is useful in space research because is the principal perturbation in aircrafts to follow a pure geodesic orbit. Nowadays, there are models to estimate atmospheric density, such as the Jacchia-Bowman model. However, there are very few measurements of this parameter in situ. On the other hand, currently, there is great interest in the space industry for the development and deployment of nanosatellites as low-cost instruments that can be used to carry out scientific research and validation of new developments. In this work, the necessary requirements for the design of a nanosatellite as a tool for the study of the ionosphere are analyzed and determined, as well as its limitations and the necessary processes to carry out a mission that provides useful information. Said contributions include the contribution of information for the improvement of the different atmospheric models such as the Jacchia-Bowman that will help us with the nanosatellite mission.
{"title":"Determining the accuracy and feasibility of measuring atmospheric density in the ionosphere through a nanosatellite","authors":"J. P. S. H. Moreno, Ana. R. Fischer-Meza, Alfredo. Mejía-Torres, Miguel A. Arellano-Serrano, P. Rodrigo, H. E. Gilardi-Velázquez","doi":"10.1109/CONCAPAN48024.2022.9997696","DOIUrl":"https://doi.org/10.1109/CONCAPAN48024.2022.9997696","url":null,"abstract":"Atmospheric research impacts various sectors such as commercial aviation activities, maritime transport, climatological analysis, and space research, among others. Knowing the atmospheric density of the ionosphere is useful in space research because is the principal perturbation in aircrafts to follow a pure geodesic orbit. Nowadays, there are models to estimate atmospheric density, such as the Jacchia-Bowman model. However, there are very few measurements of this parameter in situ. On the other hand, currently, there is great interest in the space industry for the development and deployment of nanosatellites as low-cost instruments that can be used to carry out scientific research and validation of new developments. In this work, the necessary requirements for the design of a nanosatellite as a tool for the study of the ionosphere are analyzed and determined, as well as its limitations and the necessary processes to carry out a mission that provides useful information. Said contributions include the contribution of information for the improvement of the different atmospheric models such as the Jacchia-Bowman that will help us with the nanosatellite mission.","PeriodicalId":138415,"journal":{"name":"2022 IEEE 40th Central America and Panama Convention (CONCAPAN)","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-11-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123063222","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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