Rooel Campos Rodríguez, Angéica Torres-Contreras, Ana Gabriela Castro-Brenes, Rubén Calderón-Cerdas
El aumento en la generación de residuos, como consecuencia del incremento poblacional, provoca la búsqueda de alternativas que permitan un manejo y disposición de los residuos. En esta investigación, se comparó la fertilización química y orgánica a partir de sustratos obtenidos de residuos sólidos de un centro educativo de secundaria para el cultivo de lechuga. Para la comparación de insumos químicos y orgánicos, se estableció un experimento segregados por tres tratamientos: orgánico, químico y un testigo sin fertilización. Durante un periodo de tiempo de siete semanas, se evaluó número de hojas, diámetro de la planta, diámetro del tallo altura de tallo, peso seco raíz, peso seco de lechuga, contenido relativo de agua (CRA) y el color. Como resultados, se obtuvo que ningún tratamiento presentó diferencias significativas (p>0,05) para cada una de las variables evaluadas. Sugiriendo ello, que un fertilizante orgánico aplicado a una dosis que contemple los niveles de elementos en suelo y de las necesidades del cultivo, puede ser igualmente productivo que un sistema químico. Esto con la subsecuente disminución de gases de efecto invernadero y contaminación del agua, suelo y aire.
{"title":"Capacidad productiva de un fertilizante orgánico elaborado a partir de residuos sólidos para el cultivo de lechuga","authors":"Rooel Campos Rodríguez, Angéica Torres-Contreras, Ana Gabriela Castro-Brenes, Rubén Calderón-Cerdas","doi":"10.18845/tm.v36i1.5823","DOIUrl":"https://doi.org/10.18845/tm.v36i1.5823","url":null,"abstract":"El aumento en la generación de residuos, como consecuencia del incremento poblacional, provoca la búsqueda de alternativas que permitan un manejo y disposición de los residuos. En esta investigación, se comparó la fertilización química y orgánica a partir de sustratos obtenidos de residuos sólidos de un centro educativo de secundaria para el cultivo de lechuga. Para la comparación de insumos químicos y orgánicos, se estableció un experimento segregados por tres tratamientos: orgánico, químico y un testigo sin fertilización. Durante un periodo de tiempo de siete semanas, se evaluó número de hojas, diámetro de la planta, diámetro del tallo altura de tallo, peso seco raíz, peso seco de lechuga, contenido relativo de agua (CRA) y el color. Como resultados, se obtuvo que ningún tratamiento presentó diferencias significativas (p>0,05) para cada una de las variables evaluadas. Sugiriendo ello, que un fertilizante orgánico aplicado a una dosis que contemple los niveles de elementos en suelo y de las necesidades del cultivo, puede ser igualmente productivo que un sistema químico. Esto con la subsecuente disminución de gases de efecto invernadero y contaminación del agua, suelo y aire.","PeriodicalId":42957,"journal":{"name":"Tecnologia en Marcha","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84167826","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}
Ronald Jimenez-Salas, Ronald Brenes-Brenes, J. Rodríguez-Yañéz, Jean Sanabria-Chinchilla
En esta investigación se estudió la afectación del ambiente sobre la corrosión del acero al bajo carbono, en una región tropical de la zona central de Costa Rica, con el objetivo de establecer la variación de la velocidad de corrosión en función del ángulo de exposición. Para tal fin se colocaron probetas a diferentes ángulos (0°,30°,45°,60° y 90°), en tres estaciones a lo largo del Valle Central; asimismo se midieron los parámetros medioambientes como humedad, tiempo de humectación, temperatura y la presencia de contaminantes atmosféricos, como los sulfatos y los cloruros. Como principales resultados se determinó que el acero presentó un aumento lineal de la corrosión con la disminución del ángulo con respecto a la horizontal, así mismo la corrosión es uniforme en ángulos menores a 60 grados, presentando corrosión parcial en ángulos elevados, en especial para caras protegidas. La corrosividad se ubica en un nivel urbano leve tipo C2, según la normativa ISO.
{"title":"Corrosión atmosférica del acero al bajo carbono, a diferentes ángulos de exposición, en un ambiente tropical","authors":"Ronald Jimenez-Salas, Ronald Brenes-Brenes, J. Rodríguez-Yañéz, Jean Sanabria-Chinchilla","doi":"10.18845/tm.v36i1.5845","DOIUrl":"https://doi.org/10.18845/tm.v36i1.5845","url":null,"abstract":"En esta investigación se estudió la afectación del ambiente sobre la corrosión del acero al bajo carbono, en una región tropical de la zona central de Costa Rica, con el objetivo de establecer la variación de la velocidad de corrosión en función del ángulo de exposición. Para tal fin se colocaron probetas a diferentes ángulos (0°,30°,45°,60° y 90°), en tres estaciones a lo largo del Valle Central; asimismo se midieron los parámetros medioambientes como humedad, tiempo de humectación, temperatura y la presencia de contaminantes atmosféricos, como los sulfatos y los cloruros. Como principales resultados se determinó que el acero presentó un aumento lineal de la corrosión con la disminución del ángulo con respecto a la horizontal, así mismo la corrosión es uniforme en ángulos menores a 60 grados, presentando corrosión parcial en ángulos elevados, en especial para caras protegidas. La corrosividad se ubica en un nivel urbano leve tipo C2, según la normativa ISO.","PeriodicalId":42957,"journal":{"name":"Tecnologia en Marcha","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72699318","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}
El objetivo del trabajo fue realizar observaciones en las protofilas de plántulas de tacaco. Se sembraron 50 semillas de tacaco, y se evaluaron las protofilas de las plántulas emergidas, hasta los 91 días después de siembra. Se encontraron protofilas con uno, dos, tres, cuatro, cinco, seis y siete lóbulos cada una. En la presente investigación se informa por primera vez sobre la existencia de heteroblastia (diferente número de lóbulos) en las protofilas de tacaco, lo que representa un hallazgo que puede ilustrar los cambios evolutivos recientes de esta especie.
{"title":"Primer informe sobre heteroblastia en protofilas de tacaco (Sechium tacaco)","authors":"J. E. Monge-Pérez, Michelle Loría-Coto","doi":"10.18845/tm.v36i1.5899","DOIUrl":"https://doi.org/10.18845/tm.v36i1.5899","url":null,"abstract":"El objetivo del trabajo fue realizar observaciones en las protofilas de plántulas de tacaco. Se sembraron 50 semillas de tacaco, y se evaluaron las protofilas de las plántulas emergidas, hasta los 91 días después de siembra. Se encontraron protofilas con uno, dos, tres, cuatro, cinco, seis y siete lóbulos cada una. En la presente investigación se informa por primera vez sobre la existencia de heteroblastia (diferente número de lóbulos) en las protofilas de tacaco, lo que representa un hallazgo que puede ilustrar los cambios evolutivos recientes de esta especie.","PeriodicalId":42957,"journal":{"name":"Tecnologia en Marcha","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-12-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89145621","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}
Juan Luis Crespo-Mariño, Mauricio Rodríguez-Calvo, Juan Esquivel-Rodríguez
{"title":"Contribuciones especiales a la Iniciativa de Desarrollo de Investigación de la Conferencia","authors":"Juan Luis Crespo-Mariño, Mauricio Rodríguez-Calvo, Juan Esquivel-Rodríguez","doi":"10.18845/tm.v35i9.6496","DOIUrl":"https://doi.org/10.18845/tm.v35i9.6496","url":null,"abstract":"","PeriodicalId":42957,"journal":{"name":"Tecnologia en Marcha","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80865897","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}
The development of projects related to the Internet of Things has generated a significant impact on the growth of the software industry. Although there are several alternatives to their development, users are limited by inherent factors, such as vendor lock-in, software development flexibility, and security. This article shows a platform design that provides a deployment and management system for IoT projects avoiding some of the limitations of the current tools, such as vendor lockin and limitations in the development technologies.
{"title":"Design of a microkernelbased services manager for IoT with isolated processing","authors":"Jose Antonio Ortega-González, Luis G. León-Vega","doi":"10.18845/tm.v35i9.6492","DOIUrl":"https://doi.org/10.18845/tm.v35i9.6492","url":null,"abstract":"The development of projects related to the Internet of Things has generated a significant impact on the growth of the software industry. Although there are several alternatives to their development, users are limited by inherent factors, such as vendor lock-in, software development flexibility, and security. This article shows a platform design that provides a deployment and management system for IoT projects avoiding some of the limitations of the current tools, such as vendor lockin and limitations in the development technologies.","PeriodicalId":42957,"journal":{"name":"Tecnologia en Marcha","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74998888","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}
Karen Dayana Tovar-Parra, Luis Alexander Calvo-Valverde, Ernesto Montero-Zeledón, Mac Arturo Murillo-Fernández, Jose Esteban Perez-Hidalgo, Dionisio Alberto Gutiérrez-Fallas
Melanoma is one of the most aggressive skin cancers, however, its early detection can significantly increase probabilities to cure it. Unfortunately, it is one of the most difficult skin cancers to detect, its detection relies mainly on the dermatologist’s expertise and experience with Melanoma. This research deals with targeting most of the common Melanoma stains or spots that could potentially evolve to Melanoma skin cancer. Region-based Convolutional Neural Networks were used as the model to detect and segment images of the skin area of interest. The neural network model is focused on providing instance segmentation rather than only a boxbounding object detection. The Mask R-CNN model was implemented to provide a solution for small trained datasets scenarios. Two pipelines were implemented, the first one was with only the Region-Based Convolutional Neural Network and the other one was a combined pipeline with a first stage using Mask R-CNN and then getting the result to use as feedback in a second stage implementing Grabcut, which is another segmentation method based on graphic cuts. Results demonstrated through Dice Similarity Coefficient and Jaccard Index that Mask R-CNN alone performed better in proper segmentation than Mask R-CNN + Grabcut model. In both models’ results, variation was very small when the training dataset size changed between 160, 100, and 50 images. In both of the pipelines, the models were capable of running the segmentation correctly, which illustrates that focalization of the zone is possible with very small datasets and the potential use of automatic segmentation to assist in Melanoma detection.
{"title":"Automatic image segmentation using Region-Based convolutional networks for Melanoma skin cancer detection","authors":"Karen Dayana Tovar-Parra, Luis Alexander Calvo-Valverde, Ernesto Montero-Zeledón, Mac Arturo Murillo-Fernández, Jose Esteban Perez-Hidalgo, Dionisio Alberto Gutiérrez-Fallas","doi":"10.18845/tm.v35i9.6479","DOIUrl":"https://doi.org/10.18845/tm.v35i9.6479","url":null,"abstract":"Melanoma is one of the most aggressive skin cancers, however, its early detection can significantly increase probabilities to cure it. Unfortunately, it is one of the most difficult skin cancers to detect, its detection relies mainly on the dermatologist’s expertise and experience with Melanoma. This research deals with targeting most of the common Melanoma stains or spots that could potentially evolve to Melanoma skin cancer. Region-based Convolutional Neural Networks were used as the model to detect and segment images of the skin area of interest. The neural network model is focused on providing instance segmentation rather than only a boxbounding object detection. The Mask R-CNN model was implemented to provide a solution for small trained datasets scenarios. Two pipelines were implemented, the first one was with only the Region-Based Convolutional Neural Network and the other one was a combined pipeline with a first stage using Mask R-CNN and then getting the result to use as feedback in a second stage implementing Grabcut, which is another segmentation method based on graphic cuts. Results demonstrated through Dice Similarity Coefficient and Jaccard Index that Mask R-CNN alone performed better in proper segmentation than Mask R-CNN + Grabcut model. In both models’ results, variation was very small when the training dataset size changed between 160, 100, and 50 images. In both of the pipelines, the models were capable of running the segmentation correctly, which illustrates that focalization of the zone is possible with very small datasets and the potential use of automatic segmentation to assist in Melanoma detection.","PeriodicalId":42957,"journal":{"name":"Tecnologia en Marcha","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74142789","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}
Nowadays, deep learning has become one of the most popular solutions for computer vision, and it has also included the Edge. It has influenced the System-on-Chip (SoC) vendors to integrate accelerators for inference tasks into their SoCs, including NVIDIA, NXP, and Texas Instruments embedded systems. This work explores the performance of the NXP i.MX8M Plus Neural Processing Unit (NPU) as one of the solutions for inference tasks. For measuring the performance, we propose an experiment that uses a GStreamer pipeline for inferring license plates, which is composed of two stages: license plate detection and character inference. The benchmark takes execution time and CPU usage samples within the metrics when running the inference serially and parallel. The results show that the key benefit of using the NPU is the CPU freeing for other tasks. After offloading the license plate detection to NPU, we lowered the overall CPU consumption by 10x. The performance obtained has an inference rate of 1 Hz, limited by the character inference.
{"title":"Benchmarking the NXP i.MX8M+ neural processing unit: smart parking case study","authors":"Edgar Chaves-González, Luis G. León-Vega","doi":"10.18845/tm.v35i9.6487","DOIUrl":"https://doi.org/10.18845/tm.v35i9.6487","url":null,"abstract":"Nowadays, deep learning has become one of the most popular solutions for computer vision, and it has also included the Edge. It has influenced the System-on-Chip (SoC) vendors to integrate accelerators for inference tasks into their SoCs, including NVIDIA, NXP, and Texas Instruments embedded systems. This work explores the performance of the NXP i.MX8M Plus Neural Processing Unit (NPU) as one of the solutions for inference tasks. For measuring the performance, we propose an experiment that uses a GStreamer pipeline for inferring license plates, which is composed of two stages: license plate detection and character inference. The benchmark takes execution time and CPU usage samples within the metrics when running the inference serially and parallel. The results show that the key benefit of using the NPU is the CPU freeing for other tasks. After offloading the license plate detection to NPU, we lowered the overall CPU consumption by 10x. The performance obtained has an inference rate of 1 Hz, limited by the character inference.","PeriodicalId":42957,"journal":{"name":"Tecnologia en Marcha","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79067105","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}
Daniel Amador, Carlos Gamboa-Venegas, Ernesto García, Andrés Segura-Castillo
Social media has modified the way that people access news and debate about public issues. Although access to a myriad of data sources can be considered an advantage, some new challenges have emerged, as issues about content legitimacy and veracity start to prevail among users. That transformation of the public sphere propels problematic situations, such as misinformation and fake news. To understand what type of information is being published, it is possible to categorize news automatically using computational tools. Thereby, this short paper presents a platform to retrieve and analyze news, along with promising results towards automatic news classification using a topic modeling approach, which should help audiences to identify news content easier and discusses possible routes to improve the situation in the near future.
{"title":"Automatic social media news classification: a topic modeling approach","authors":"Daniel Amador, Carlos Gamboa-Venegas, Ernesto García, Andrés Segura-Castillo","doi":"10.18845/tm.v35i9.6477","DOIUrl":"https://doi.org/10.18845/tm.v35i9.6477","url":null,"abstract":"Social media has modified the way that people access news and debate about public issues. Although access to a myriad of data sources can be considered an advantage, some new challenges have emerged, as issues about content legitimacy and veracity start to prevail among users. That transformation of the public sphere propels problematic situations, such as misinformation and fake news. To understand what type of information is being published, it is possible to categorize news automatically using computational tools. Thereby, this short paper presents a platform to retrieve and analyze news, along with promising results towards automatic news classification using a topic modeling approach, which should help audiences to identify news content easier and discusses possible routes to improve the situation in the near future.","PeriodicalId":42957,"journal":{"name":"Tecnologia en Marcha","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75065156","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}
María Fernanda Madriz-Ramírez, Kevin Alberto Solano-Núñez, Mauricio Rodríguez-Calvo
The cooling system is one of the most important parts of a robot, a correct design allows it to increase its capacity while reducing the chances of a malfunction. In general, cooling systems for humanoid robots require special characteristics to not interfere with the optimal operation; aspects such as weight, size, materials, and positioning of this system are crucial for maximum efficiency. The current problem in this design is that the cooling system needs to maintain its power to perform tasks when lifting heavy weights without consequences such as reduced mobility of the joint, and therefore decrease the robot’s efficiency. In this paper, we studied, analyzed, and discarded existing options of electric motor actuators. Once the viable options were obtained, so we proceed to make a proper design, then was made a computational fluid dynamics study (CFD) to get heat extraction measurements as well as fluid velocity, essential to make the final decision, solving the initial problem.
{"title":"Analysis of a cooling system for robotic joints using a computational fluid dynamics study","authors":"María Fernanda Madriz-Ramírez, Kevin Alberto Solano-Núñez, Mauricio Rodríguez-Calvo","doi":"10.18845/tm.v35i9.6488","DOIUrl":"https://doi.org/10.18845/tm.v35i9.6488","url":null,"abstract":"The cooling system is one of the most important parts of a robot, a correct design allows it to increase its capacity while reducing the chances of a malfunction. In general, cooling systems for humanoid robots require special characteristics to not interfere with the optimal operation; aspects such as weight, size, materials, and positioning of this system are crucial for maximum efficiency. The current problem in this design is that the cooling system needs to maintain its power to perform tasks when lifting heavy weights without consequences such as reduced mobility of the joint, and therefore decrease the robot’s efficiency. In this paper, we studied, analyzed, and discarded existing options of electric motor actuators. Once the viable options were obtained, so we proceed to make a proper design, then was made a computational fluid dynamics study (CFD) to get heat extraction measurements as well as fluid velocity, essential to make the final decision, solving the initial problem.","PeriodicalId":42957,"journal":{"name":"Tecnologia en Marcha","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75108312","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}
Luis Gerardo León-Vega, Eduardo Salazar-Villalobos, Jorge Castro-Godínez
Performing inference of complex machine learning (ML) algorithms at the edge is becoming important to unlink the system functionality from the cloud. However, the ML models increase complexity faster than the available hardware resources. This research aims to accelerate machine learning by offloading the computation to low-end FPGAs and using approximate computing techniques to optimise resource usage, taking advantage of the inaccurate nature of machine learning models. In this paper, we propose a generic matrix multiply-add processing element design, parameterised in datatype, matrix size, and data width. We evaluate the resource consumption and error behaviour while varying the matrix size and the data width given a fixed-point data type. We determine that the error scales with the matrix size, but it can be compensated by increasing the data width, posing a trade-off between data width and matrix size with respect to the error.
{"title":"Accelerating machine learning at the edge with approximate computing on FPGAs","authors":"Luis Gerardo León-Vega, Eduardo Salazar-Villalobos, Jorge Castro-Godínez","doi":"10.18845/tm.v35i9.6491","DOIUrl":"https://doi.org/10.18845/tm.v35i9.6491","url":null,"abstract":"Performing inference of complex machine learning (ML) algorithms at the edge is becoming important to unlink the system functionality from the cloud. However, the ML models increase complexity faster than the available hardware resources. This research aims to accelerate machine learning by offloading the computation to low-end FPGAs and using approximate computing techniques to optimise resource usage, taking advantage of the inaccurate nature of machine learning models. In this paper, we propose a generic matrix multiply-add processing element design, parameterised in datatype, matrix size, and data width. We evaluate the resource consumption and error behaviour while varying the matrix size and the data width given a fixed-point data type. We determine that the error scales with the matrix size, but it can be compensated by increasing the data width, posing a trade-off between data width and matrix size with respect to the error.","PeriodicalId":42957,"journal":{"name":"Tecnologia en Marcha","volume":null,"pages":null},"PeriodicalIF":0.1,"publicationDate":"2022-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85261687","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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