THE IMPACT OF ACTIVE LEARNING WITH ADAPTIVE LEARNING SYSTEMS IN GENERAL EDUCATION INFORMATION TECHNOLOGY COURSES

An adaptive learning system is an effective educational tool that meets the individual needs of students, but it is limited in fostering student learning by itself. With active engagement, students learn better than with adaptive learning systems alone. In this study, we investigate the impact of an adaptive learning system with active learning projects on student learning in general education information technology courses. We believe that today\u27s classroom calls for adaptive learning to serve the needs of diverse student populations. Active learning through real-life hands-on learning activities can enhance student learning by allowing them to apply their knowledge to authentic projects. In the classroom, we often find that learning computing with authentic hands-on activities is not only useful, but it contributes to improving student motivation and confidence

Communication-Efficient On-Device Machine Learning: Federated Distillation and Augmentation under Non-IID Private Data

On-device machine learning (ML) enables the training process to exploit a massive amount of user-generated private data samples. To enjoy this benefit, inter-device communication overhead should be minimized. With this end, we propose federated distillation (FD), a distributed model training algorithm whose communication payload size is much smaller than a benchmark scheme, federated learning (FL), particularly when the model size is large. Moreover, user-generated data samples are likely to become non-IID across devices, which commonly degrades the performance compared to the case with an IID dataset. To cope with this, we propose federated augmentation (FAug), where each device collectively trains a generative model, and thereby augments its local data towards yielding an IID dataset. Empirical studies demonstrate that FD with FAug yields around 26x less communication overhead while achieving 95-98% test accuracy compared to FL.Comment: presented at the 32nd Conference on Neural Information Processing Systems (NIPS 2018), 2nd Workshop on Machine Learning on the Phone and other Consumer Devices (MLPCD 2), Montr\'eal, Canad

Unveiling the Direct Correlation between the CVD-Grown Graphene and the Growth Template

Chemical vapor deposition (CVD) is known to produce continuous, large-area graphene sheet with decent physical properties. In the CVD process, catalytic metal substrates are typically used as the growth template, and copper has been adopted as the representative material platform due to its low carbon solubility and resulting monolayer graphene growth capability. For the widespread industrial applications of graphene, achieving the high-quality is essential. Several factors affect the qualities of CVD-grown graphene, such as pressure, temperature, carbon precursors, or growth template. In this work, we provide detailed analysis on the direct relation between the metallic growth substrate (copper) and overall properties of the resulting CVD-grown graphene. The surface morphology of copper substrate was modulated via simple chemical treatments, and its effect on physical, optical, and electrical properties of graphene was analyzed. Based on these results, we propose a simple synthesis route to produce high-quality, continuous, monolayer graphene sheet, which can facilitate the commercialization of CVD graphene into realit

Electronic Payment Systems – Payment Gateways and Data Security Standards

The use of mobile applications has allowed electronic transactions to be made anytime, anywhere, and by anyone. The Internet has made it possible for businesses to expand their reach across the globe. As a guiding agent for purchasing decisions, social media’s proliferation has expanded businesses’ ability to generate revenue [1]. In short, e-commerce has become a mainstay in the way consumers shop. The findings related to this study are three-fold. First, a systematic and rigorous approach is applied to research the importance of Payment Gateways and the Payment Card Industry Data Security Standards in today’s electronic marketplace. Next, a quantitative survey was administered to college-level students to validate the need to expand the course curriculum. Lastly, suggestions for future studies are provided to help bridge the gap between academia and the corporate world. When combined, this information will equip students with the needed knowledge to succeed when they enter the e-commerce workforce. Keywords: Payment Gateways, Data Security Standards, Electronic Payment Systems DOI: 10.7176/JEP/12-3-21 Publication date: January 31st 2021

Stepwise heating in Stille polycondensation toward no batch-to-batch variations in polymer solar cell performance

For a given ??-conjugated polymer, the batch-to-batch variations in molecular weight (Mw) and polydispersity index (??) can lead to inconsistent process-dependent material properties and consequent performance variations in the device application. Using a stepwise-heating protocol in the Stille polycondensation in conjunction with optimized processing, we obtained an ultrahigh-quality PTB7 polymer having high Mw and very narrow ??. The resulting ultrahigh-quality polymer-based solar cells demonstrate up to 9.97% power conversion efficiencies (PCEs), which is over 24% enhancement from the control devices fabricated with commercially available PTB7. Moreover, we observe almost negligible batch-to-batch variations in the overall PCE values from ultrahigh-quality polymer-based devices. The proposed stepwise polymerization demonstrates a facile and effective strategy for synthesizing high-quality semiconducting polymers that can significantly improve device yield in polymer-based solar cells, an important factor for the commercialization of organic solar cells, by mitigating device-to-device variations

Interface engineering of graphene for universal applications as both anode and cathode in organic photovoltaics

The high transparency of graphene, together with its good electrical conductivity and mechanical robustness, enable its use as transparent electrodes in optoelectronic devices such as solar cells. While initial demonstrations of graphene-based organic photovoltaics (OPV) have been promising, realization of scalable technologies remains challenging due to their performance and, critically, poor device reproducibility and yield. In this work, we demonstrate by engineering the interface between graphene and organic layers, device performance and yield become close to devices using indium tin oxide. Our study confirms that the key issue leading to the poor performance or irreproducibility in graphene-based OPV originates from the graphene interface, and can be addressed by a simple interface modification method introduced in this work. We also show similar approach allows graphene to be used as cathode in inverted OPV geometry, thereby demonstrating the universal application of graphene as transparent conductors for both the anode and cathode.open11

Electronic Payment Systems: Payment Gateways and Data Security Standards

The use of smartphones, tablets, and laptops allow electronic transactions to be made anytime, anywhere, and by anyone. This version of commerce, known as e-commerce or digital commerce, has become a mainstay in the way consumers shop. Online payments have essentially made cash payment systems virtually obsolete. Also, the Internet has made it possible for businesses to expand their reach across the globe. More importantly, due to the proliferation of social media as a guiding agent for purchasing decisions, e-commerce has evolved into one of the most significant driving forces into how businesses generate revenue (Wong 2018). According to the U.S. Census Bureau (2019), the year’s retail e-commerce sales reached 154.7 billion, and the data indicated that sales would continue to grow. Coexisting with the steady rise of sales is the need for skilled and knowledgeable workers. Torpey (2018) shared a Bureau of Labor and Statistics report which revealed that e-commerce employment is expected to reach approximately 450,000 by 2026. Many of these jobs require advanced knowledge of credit card standards and acceptance procedures. Aligned to these expectations, the purpose of this project was to garner an understanding of payment gateways (PGs) and Payment Card Industry Data Security Standards (PCI-DSS) to develop material to enhance an undergraduate e-commerce curriculum. The outcome of this research will be three-fold. First, it will offer qualitative outcomes on how students and teachers collaborated on gathering appropriate learning material to be used in the classroom. Second, the results of a quantitative student survey, administered near the end of the semester, will provide supporting evidence of the need to add this material into the curriculum. Third, using a scholarly practitioner model, the outcomes will bridge the gap between academia and real-world applications to equip students with the necessary knowledge to enter the workforce

Fabrication of microfluidic devices for artificial respiration

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2007.Includes bibliographical references (p. 101-108).We are developing elastomeric polydimethylsiloxane (PDMS) microfluidic devices incorporated with photoactive thin films to create an implantable artificial respiration platform. Whereas state-of-the-art respiration support machines deliver oxygen gas directly to the blood via external macroscale devices, our technique utilizes a biomimetic photocatalytic process to generate energy from light and thus produce dissolved oxygen from water which is already present in the blood. Blood oxygenation will be achieved by the interaction between the photoactivated metal oxide film and blood in the setting of a molded microfluidic conduit, providing a stable and implantable oxygenation platform. As a basic, scalable building block, we developed a noble "network" design which was structurally similar to the native pulmonary capillary network. The interconnected channel geometry was designed in such a way to minimize shear stress and reduce hemolysis and thrombosis inside the microchannel. It allowed alternative flow pathways in the event of single channel occlusion while minimizing the establishment of detrimental pressure gradients. The hemocompatibility analysis demonstrated that the network construct showed acceptable levels of hemolysis rate (< 8%) and thrombus formation.(cont.) Critical to the success of this project is the understanding of the manufacture parameters for microfluidic devices molded from elastomeric materials like PDMS. In the initial development of our work, we performed the following three tasks to generate manufacture protocols for elastomeric microfluidic devices that will be ultimately used for biological applications: 1) Curing schedules of the heat-cure PDMS elastomers under various fabrication parameters were characterized. 2) The interlayer bonding chemistry of the double layer PDMS device was analyzed followed by subsequent mechanical analysis. 3) The efficacy of various surface treatment techniques on hydrophobic PDMS surfaces was investigated using fluorescently tagged bacteria (E. Coli) flowed through microchannels as reporter particles to measure non-specific adhesion, which will provide useful information in minimizing channel fouling for biological applications.by Hyesung Park.S.M