ABSTRACT
In this paper, we reported on the lattice distortion, surface morphologies, vacancy defects and electrochemical performance that had been observed in Na3V2(PO4)2F3 prepared at different annealing temperatures. X-ray diffraction indicated that all the samples were single phase materials with tetragonal structure and exhibited lattice distortion with the increase of annealing temperatures. A possible mechanism causing the strain-induced lattice distortion had been discussed. Moreover, scanning electron microscopy and positron annihilation techniques were used to study the grain size and vacancy defects as a function of annealing temperatures. The superior electrochemical performance of Na3V2(PO4)2F3 electrode was obtained at the annealing temperature of 350 degrees C with 167.73 F center dot g-1 specific capacitance and 85% capacitance retention. The better electrochemical performance was due to the synergistic effects of grain size and vacancy defect regulated by the annealing temperatures. These results could provide experimental basis for enhancing electrochemical performance of Na3V2(PO4)2F3 in sodium-ion battery area applications. (c) 2023 Elsevier B.V. All rights reserved.
ABSTRACT
Object detection is the task of classifying and finding certain objects including people, cars, handwritten text, and more. This is a growing field with application in several fields, identifying and locating cars, pedestrians and other objects for self-driving cars, monitoring objects such as crops, or the ball during sports, facial detection for protection and many more. Handwritten text recognition comprises character recognition and digit recognition. An effective CNN based model with high accuracy can help an OCR (Optical Character Recognition) system for accurate conversion of written text into digital text. In this work, we have explained a CNN based approach for recognizing hand written digits and predict the written numbers.
ABSTRACT
Games in any form have always been a part of human life. These play a very important part in socializing and competitive enhancement of human nature. With the invention of computer and various other portal electronic devices, video games came into picture. Advancement in computer technology in last few decades and accessibility of the same has exponentially increased the number of people playing video games. These video games in competitive form are called esports which stands for electronic sports. Nevertheless with the recent outburst because of COVID, the engagement on the same has peaked like never before. Further, these have some positive and some negative outcomes on the life of people.
ABSTRACT
51-year-old man (C.P.) had a diffuse-axonal-injury after falling from a 5-meter height, followed by a 22-minute anoxia due to a cardiac arrest. In the ICU, he tested positive to COVID-19, and needed intubation. After coronavirus infection, C.P. presented Guillain-Barre syndrome. 2months after discharge, he was admitted to rehabilitation. DTI tractography for evaluation of the structural integrity of white matter tracts revealed: i) Lesions in the basal ganglia;ii) Sequelary lesions in the right frontal, cortical, subcortical, temporal, parieto-occipital and cerebellar hemispheres;iii) Asymmetry of the corticospinal tracts - less fibers on the left;iv) Poor definition of the fibers of the right arcuate fasciculus;v)Asymmetrical thinning of the cortico-ponto-cerebellar tracts, worse on the left, and more discreetly in the spinocerebellar tracts. Based on this, C.P. underwent 4 different 30-session tDCS protocols consisting of twice-daily 20min 2mA sessions (10min interval), 5days/week (120sessions total), combined with physiotherapy, cognitive, swallowing and speech therapy. Montages: Pr1 (anode: Cz - 5x10cm;cathode: 10th Thoracic Vertebra - 5x7cm);Pr2 (1 - anode:C3;cathode:Fp2 / 2 - anode: Cerebellum;cathode:Fp2);Pr3 (anode:F3;cathode:Fp2) and Pr4 (anode:Cp5;cathode:Fp2). Except for Pr1, electrode size for all protocols were 5x7cm. We used the Coma Recovery Scale (CRS-R) and Rancho Los Amigos Scale (RLAS) for clinical assessments at the baseline and after every 10 sessions until the end of the intervention. At the baseline, C.P. presented a minimal responsive state of consciousness (CRS-R: 3;RLAS: Level 1) and tolerated well the tDCS interventions. CRS-R scores gradually improved in various domains during the treatment. At the end, RLAS score was level 5 and CRS-R, 19. Our preliminary results suggest DTI tractography may be a potential biomarker to guide more personalized tDCS interventions for complex cases of patients with acquired brain injuries. A second DTI tractography will be made in the future for comparison purposes. Research Category and Technology and Methods Clinical Research: 9. Transcranial Direct Current Stimulation (tDCS) Keywords: Acquired Brain Injury, Traumatic Brain Injury, COVID-19, Guillain Barre SyndromeCopyright © 2023
ABSTRACT
During the closure of K-12 schools and universities due to the COVID-19 pandemic, many educators turned to web conferencing tools such as Zoom and WebEx to deliver online lectures. For courses with labs, some teachers provide recorded videos of real labs. Watching recorded lab videos is a passive experience, as the procedures and point of view are fixed, and students do not have any control of the lab and thus miss the opportunity to explore different options, including making mistakes that is important part of the learning process. One approach that holds great potential to enhance laboratory experience for online education is the use of computer-based modeling and simulation tools. Simulation based virtual laboratories emulate lab equipment and configurations in highly realistic 3D environments and can provide very effective learning experiences. While there exist limited interactive lab computer simulations for various subjects, their presentations are still very primitive and often lack realism and complexity. This paper presents methodologies and preliminary findings on rapid development of advanced virtual labs using modeling and simulation for in-person and online education. The importance of modeling and simulation has long been recognized by the scientific community and agencies such as DoD and NSF. However, high-quality simulations are not commonplace, and simulations have not been widely employed in education. Existing simulations for education lack interoperability and compatibility. While there are sporadic uses of computer-based simulations in education that were developed in a piecemeal fashion, there was never systematic development at an industry level for such purposes. Virtual lab development usually require substantial amount of effort and lack of systematic research on rapid virtual lab development hinders their wide use in education. This paper proposes a wholistic and systematic approach for addressing the issues in rapid lab simulation development from several perspectives, including rapid generation of virtual environment, integration of state-of-the-art industry leading software tools, advanced software design techniques that enables large scale software reuse, and innovative user interface design that facilitate the configuration and use of virtual labs by instructors and students. This paper will implement a virtual circuit lab that emulates a circuit lab for the course PHYS 303 offered at Old Dominion University and will be used to elucidate the crucial methodologies for rapid virtual lab development. The virtual lab contains highly realistic visual renderings and accurate functional representations of sophisticated equipment, such as digital oscilloscopes, function generators, and digital multimeters, and authentic rendition of the lab space. The virtual lab allows analog and digital circuit simulation by integrating the de-facto industry standard circuit simulation engine SPICE and Xspice, supporting the circuit labs in course PHYS 303. The Unity game engine is used to develop the front end of the virtual lab. Advanced software development methodologies will be investigated to facilitate software reuse and rapid development, e.g., the same simulation code can be used to support equipment manufactured by different vendors. The paper will also investigate the impact of fidelity of the virtual lab, e.g., equipment and lab room, on student learning outcomes and efficacy. © American Society for Engineering Education, 2022.
ABSTRACT
Because of the Covid-19 Pandemic during academic year 2020-2021, many of the classes and laboratories in our undergraduate Electrical Engineering (EE) program were conducted remotely, making tremendous use of videoconferencing technologies such as Microsoft Teams, and simulation engines such as National Instruments' MultiSimTM. As we began to move back to “in person” learning for the Fall of 2021, our EE faculty observed some early weaknesses in student achievement of ABET EE student outcome #6 (an ability to develop and conduct appropriate experimentation, analyze and interpret data, and use engineering judgment to draw conclusions). We found that while students demonstrated excellent proficiency in using modern tools such as MATLABTM and MultiSimTM (which had been used extensively during remote classes), they appeared considerably weaker in making independent measurements using laboratory hardware such as oscilloscopes, dynamic signal analyzers (FFT analyzers), RF analyzers, and even commonly used voltage and current meters (which had not been used much during remote learning). Here we highlight specific student shortcomings we observed in laboratory skills as students began their in-person lab experiences during the Fall 2021 semester. We then discuss our approaches to remedy these shortcomings during the Fall 2021 semester to improve student confidence and proficiency in the use of laboratory instrumentation. We also highlight the improvements we saw in achievement of ABET student outcomes. While computer simulation has its place in undergraduate education, practical testing and measurement of electronic systems does require physical measurement and interaction using modern test equipment, and we identified some areas for timely improvement. Our focus in this paper is on improved student performance in using laboratory test equipment in Linear Circuits and Antennas courses. In the Linear Circuits course, students use the Oscilloscope and Dynamic Signal Analyzer to identify the characteristics of several op-amps and circuits (e.g, op-amp open-loop frequency response, gain-bandwidth product, slew rate, output impedance, closed-loop frequency response of an inverting amplifier), and in the in the Antennas course students use the RF analyzer to characterize the behavior of RF circuits, transmission lines and antennas. We show how our increased emphasis on lab skills for the Fall 2021 semester, coupled with unique assessment tools, significantly improved achievement of student outcome #6. More specifically we share the successes we experienced in using oral individual quizzes during lab meetings, group classroom quizzes, individual student observation of setup and measurement, and adding questions related to lab skills and experiences on hourly examinations. © American Society for Engineering Education, 2022
ABSTRACT
Summary In the novel coronavirus epidemic, Russia–Ukrainian war environment, oil, and other energy resources are in short supply. With the increase of oil prices, electric vehicles become mainstream vehicles. As the core component of electric vehicles, batteries have become an integral part of people's daily life. The development of high‐performance, pollution‐free batteries has become the focus of the world. Because of the advantages of high specific capacity, environmental friendliness and low cost, ternary cathode material have become a research hotspot of lithium‐ion batteries. This paper mainly selects high nickel ternary material as the research object, and from its working principle, composition structure, material preparation, reaction mechanism, existing problems, and modification method to six aspects of a more comprehensive overview, for future researchers to provide a beneficial reference. [ FROM AUTHOR] Copyright of International Journal of Energy Research is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)
ABSTRACT
A low-cost remote lab has been implemented to aid instructors in delivering an online electrical engineering introductory course in electric circuits during the COVID-19 pandemic. The main purpose of implementing the remote lab was to familiarize freshmen students with conventional equipment such as digital oscilloscope, function generators, power supply, multimeter and frequency counters. The integration of the remote devices in the online lectures was essential to enable students to operate the equipment and prepare them for a smooth transition upon their return to campus. The lab has also offered students the possibility of conducting basic online circuit experiments, both as part of the theoretical course and its associated lab, in a proof-of-concept paradigm or as a fully practical course. © 2022 IEEE.
ABSTRACT
Object detection is the task of classifying and finding certain objects including people, cars, handwritten text, and more. This is a growing field with application in several fields, identifying and locating cars, pedestrians and other objects for self-driving cars, monitoring objects such as crops, or the ball during sports, facial detection for protection and many more. Handwritten text recognition comprises character recognition and digit recognition. An effective CNN based model with high accuracy can help an OCR (Optical Character Recognition) system for accurate conversion of written text into digital text. In this work, we have explained a CNN based approach for recognizing hand written digits and predict the written numbers. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
ABSTRACT
Games in any form have always been a part of human life. These play a very important part in socializing and competitive enhancement of human nature. With the invention of computer and various other portal electronic devices, video games came into picture. Advancement in computer technology in last few decades and accessibility of the same has exponentially increased the number of people playing video games. These video games in competitive form are called esports which stands for electronic sports. Nevertheless with the recent outburst because of COVID, the engagement on the same has peaked like never before. Further, these have some positive and some negative outcomes on the life of people. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.