Repositorio Institucional Digital de la Universidad Nacional Arturo Jauretche - RID-UNAJ

¡Bienvenido al RID UNAJ! Aquí encontrarás tesis de grado y posgrado, artículos científicos, libros y más, todo en formato digital.

El RID UNAJ reúne toda la producción científica y académica de los estudiantes, docentes, nodocentes, investigadores y becarios de la universidad con la intención de garantizar el Acceso Abierto a la información.

Communities in RID-UNAJ

Select a community to browse its collections.

Now showing 1 - 5 of 10

Recent Submissions

Novel automatic scorpion-detection and -recognition system based on machine-learning techniques
(2021-02-26) Giambelluca, Francisco Luis; Osio, Jorge Rafael; Giambelluca, Luis A.; Cappelletti, Marcelo
All species of scorpions can inject venom, some of them even with the possibility of killing a human. Therefore, early detection and identification are essential to minimize scorpion stings. In this paper, we propose a novel automatic system for the detection and recognition of scorpions using computer vision and machine learning (ML) approaches. Two complementary image-processing techniques were used for the proposed detection method to accurately and reliably detect the presence of scorpions. The first is based on the fluorescent characteristics of scorpions when exposed to ultraviolet light, and the second on the shape features of the scorpions. Also, three models based on ML algorithms for the image recognition and classification of scorpions are compared. In particular, the three species of scorpions found in La Plata city (Argentina): Bothriurus bonariensis (of no sanitary importance), Tityus trivittatus, and Tityus confluence (both of sanitary importance) have been researched using a local binary-pattern histogram algorithm and deep neural networks with transfer learning (DNNs with TL) and data augmentation (DNNs with TL and DA) approaches. A confusion matrix and a receiver operating characteristic curve were used to evaluate the quality of these models. The results obtained show that the model of DNN with TL and DA is the most efficient at simultaneously differentiating between Tityus and Bothriurus (for health security) and between T. trivittatus and T. confluence (for biological research purposes).
Scorpion Detection and Classification Systems Based on Computer Vision as a Prevention Tool
(2022) Giambelluca, Francisco Luis; Osio, Jorge Rafael; Giambelluca, Luis; Cappelletti, Marcelo
In this paper, automatic and real-time systems were developed to detect and classify two different genera of scorpions using computer vision and deep learning techniques, with the purpose of providing a prevention tool. The images of scorpions were obtained from an arachnology laboratory in Argentina. YOLO (you only look once) and MobileNet models were implemented. The data augmentation technique was applied to significantly increase the amount of training data. High accuracy and recall values have been achieved for both models, which guarantees that they can early and successfully detect scorpions. In addition, the MobileNet model has shown to have excellent performance to detect scorpions within an uncontrolled environment, to carry out multiple detections, and to recognize their danger in case of accidents. Finally, a comparison has been made with other different machine learning-based models used to identify scorpions.
Optimization of Inverted All-Inorganic CsPbI3 and CsPbI2Br Perovskite Solar Cells by SCAPS-1D Simulation
(2022-12-09) Pinzón, Carlos; Martínez, Nahuel; Casas, Guillermo; Alvira, Fernando C.; Denon, Nicole; Brusasco, Gastón; Medina Chanduví, Hugo; Gil Rebaza, Arles V.; Cappelletti, Marcelo A.
Perovskite solar cells (PSCs) have substantially increased their power conversion efﬁciency (PCE) to more than 25% in recent years. However, the instability of these devices is still a strong obstacle for their commercial applications. Recently, all-inorganic PSCs based on CsPbI3 and CsPbI2Br as the perovskite layer have shown enhanced long-term stability, which makes them potential candidates for commercialization. Currently, all-inorganic PSCs with inverted p-i-n conﬁguration have not yet reached the high efﬁciency achieved in the normal n-i-p structure. However, the inverted p-i-n architecture has recently drawn attention of researchers because it is more suitable to prepare tandem solar cells. In this work, a theoretical study of inverted p-i-n all-inorganic PSCs based on CsPbI3 and CsPbI2Br as the perovskite layer was carried out using SCAPS-1D software (ver. 3.3.09). The performance of different architectures of PSC was examined and compared by means of numerical simulations using various inorganic materials as the hole transport layer (HTL) and the electron transport layer (ETL). The results reveal that CuI and ZnO are the most suitable as HTL and ETL, respectively. In addition, the performance of the devices was signiﬁcantly improved by optimizing the hole mobility in CuI as well as the thickness, doping density, and defect density in the absorber layer. Maximum efﬁciencies of 26.5% and 20.6% were obtained under optimized conditions for the inverted all-inorganic CsPbI3- and CsPbI2Br-based PSCs, respectively. These results indicate that further improvements in the performance of such devices are still possible.
An Approach to the Modeling and Simulation of Intra-Hospital Diseases
(2021-10) Maccallini, Lucas; Encinas, Diego; Romero, Fernando
This publication presents an approach to a simulator to recreate a large number of scenarios and to make agile decisions in the planning of a real emergency room system. A modeling and simulation focused on the point prevalence of intrahospital infections in an emergency room and how it is affected by different factors related to hospital management. To carry out the simulator modeling, the Agent-based Modeling and Simulation (ABMS) paradigm was used. Thus, different intervening agents in the emergency room environment — patients and doctors, among others— were classiﬁed. The user belonging to the health system has different data to conﬁgure the simulation, such as the number of patients, the number of available beds, etc. Based on the tests carried out and the measurements obtained, it is concluded that the disease propagation model relative to the time and contact area of the patients has greater precision than the purely statistical model of the intensive care unit.
Bibliometric Analysis of Research on Scientific Literacy between 2018 and 2022 : Science Education Subject
(2022-12) Wirzal, Mohd Dzul Hakim; Nordin, Nik Abdul Hadi Md; Bustam, Mohamad Azmi; Joselevich, Maria
This study presents the results of a bibliometric scientific literacy analysis on science education subjects. The main objectives of this study are to analyze trends in scientific publications on scientific literacy in science education subjects; identification of networks between authors, institutions, and countries; and to understand the structure and focus of research and teaching themes of scientific literacy on science education subject. This research uses 451 published documents from 2018-2022 from the SCOPUS database. VosViewer software is used to analyze and visualize research data. The results of the research show scientific publications on the topic of scientific literacy in science education subject have increased significantly in the last five years; research results on this topic are published in reputable scientific journals (ranked Q1 and Q2); United States is the country with the highest number of documents, citations, and institutions; and there are six groups of keywords used, namely scientific literacy, science education, nature of science, students, education, and teacher education. This study recommends that research at the primary and secondary education levels by taking into account aspects of SL traits can be carried out in future research.