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Learner Action Patterns in the Problem-Solving Process Related to program Code Composition Based on Tracking System Activities

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Learner Action Patterns in the Problem-Solving Process Relat...

International Conference on Informatics and Computing (ICIC)

作者： Aulia Akhrian Syahidi Ahmad Afif Supianto Tsukasa Hirashima Yutaka Watanobe Smart City Information System Applied Undergraduate Program Politeknik Negeri Banjarmasin Banjarmasin City Indonesia Research Center for Data and Information Sciences National Research and Innovation Agency (BRIN) Bandung City Indonesia Learning Engineering Laboratory Graduate School of Advanced Science and Engineering Hiroshima University Kagamiyama Higashihiroshima Japan Department of Computer Science and Engineering Division of Information Systems University of Aizu Aizu-Wakamatsu City Fukushima Japan

ISBN: (纸本)9798350345728

Learning activities are an indicator of the learner's desire to learn during the learning process. The pattern of learner action is related to learning activities. In this case, in extracting the learning process, it is necessary to collect a lot of data through analysis of the learning process. The purpose of this study is to recommend and report the performance of an activity tracking system equipped with visual artifacts as an educational data mining approach to analyze action patterns when learners complete the arrangement of program code lines in each programming problem. In this study, data were taken from activity recordings when learners used interactive learning media for a basic programming subject called TOLSYASUPI-EduMed which had problem-solving learning models embedded in their interactions. Learning Analytics is used as a method of this research and data relationships from learner actions during the learning process using the “if-then” rule. Log data is used for recording and detecting activities carried out by learners. We confirm that the results of the study are based on the findings of the data relationship that if the lines of program code are too long (more than five lines) then almost all learners experience a bottleneck condition. The completion time of each question and the number of iterations in completing the program code lines for each question have also been recorded and have a pattern of connection between the data. The information that has been obtained is then forwarded to teachers or stakeholders as key information to make appropriate feedback to learners based on the results as a means of analyzing and evaluating the programming learning process.

关键词： Visualization Codes Media Data models Recording Data mining Problem-solving

Synergistic engineering of hole transport materials in perovskite solar cells

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InfoMat 2020年第5期2卷 928-941页

作者： Sally Mabrouk Behzad Bahrami Hytham Elbohy Khan Mamun Reza Ashim Gurung Mao Liang Fan Wu Mingtai Wang Shangfeng Yang Qiquan Qiao Center for Advanced Photovoltaics Department of Electrical Engineering and Computer ScienceSouth Dakota State UniversityBrookingsSouth Dakota Physics Department Damietta UniversityNew Damietta CityEgypt Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion Department of Applied ChemistryTianjin University of TechnologyTianjinChina Key Lab of Optoelectronic Materials and Devices School of ScienceHuzhou UniversityHuzhouChina Institute of Applied Technology Hefei Institutes of Physical ScienceChinese Academy of SciencesHefeiChina Hefei National Laboratory for Physical Sciences at Microscale CAS Key Laboratory of Materials for Energy ConversionDepartment of Materials Science and EngineeringSynergetic Innovation Center of Quantum Information and Quantum PhysicsUniversity of Science and Technology of ChinaHefeiChina

In this work,methylammonium lead triiodide(CH3NH3PbI3)perovskite solar cells with efficiencies higher than 18%were achieved using a new nanocomposite hole transport layer(HTL)by doping poly(ethylenedioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)with a mixed dopant of polyaniline(PANI)and graphene oxide(GO).A synergistic engineering between GO,PANI,and PEDOT:PSS was accomplished to introduce additional energy levels between perovskite and PEDOT:PSS and increase the conductivity of PEDOT:*** probe force microscope results confirmed that adding GO to PEDOT:PSS/PANI composite significantly reduced the average surface *** increased the open circuit voltage(Voc)to 1.05 V for the GO/PEDOT:PSS/PANI nanocomposite perovskite solar cells from the pristine PEDOT:PSS(Voc=0.95 V)and PEDOT:PSS/PANI(Voc=0.99 V).In addition,adding PANI to the HTLs substantially enhanced short circuit current density(Jsc).This was supported by the current sensing-atomic force microscopy(CS-AFM)and conductivity *** PANI doped films showed superior electrical conductivity compared with those without PANI as indicated by CS-AFM *** can fill the gaps between the microflakes of GO and give rise to more compact hole transport material(HTM)*** led to a higher Jsc after doping with PANI,which was consistent with the incident photon-to-current efficiency and electrochemical impedance spectroscopy *** results of X-ray diffraction(XRD)and AFM indicated the GO/PANI doped HTMs significantly improved the crystallinity,topography,and crystal size of the perovskite film grown on their surface.A higher efficiency of 18.12%for p-i-n perovskite solar cells has been obtained by adding the mixed dopant of GO,PANI,and PEDOT:PSS,demonstrating better stability than the pristine PEDOT:PSS cell.

关键词： composite hole transport material perovskite solar cell polyaniline and graphene oxide

Constraining the global heliospheric transport of galactic cosmic rays in solar cycles 23 and 24

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arXiv 2023年

作者： Corti, Claudio Sadowski, Peter Nikonov, Nikolay Potgieter, Marius Bindi, Veronica University of Hawaii at Manoa Physics and Astronomy Department 2505 Correa Road HonoluluHI United States NASA Goddard Space Flight Center CCMC 8800 Greenbelt Road GreenbeltMD United States University of Hawaii at Manoa Information and Computer Science Department 1680 East-West Road HonoluluHI United States Christian-Albrecths University Institute for Experimental and Applied Physics Leibniztraße 11-19 Kiel Germany

Galactic cosmic rays (GCRs) are affected by solar modulation while they propagate through the heliosphere. The study of the time variation of GCR spectra observed at Earth can shed light on the underlying physical processes, specifically diffusion and particle drifts. We combine a state-of-the art 3D numerical model of GCR transport in the heliosphere with a neural-network-accelerated Markov chain Monte Carlo to constrain the rigidity and time dependence of the global transport coefficients, using precise GCR data from the PAMELA and AMS-02 experiments between 2006 and 2019. Copyright © 2023, The Authors. All rights reserved.

关键词： Cosmology

Elementary Radial Electric Dipole Excitation of Graphene Spherical Disk on Dielectric Sphere

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Elementary Radial Electric Dipole Excitation of Graphene Sph...

Ukrainian Microwave Week (UkrMW), IEEE

作者： Iryna Mikhailikova Sergii V. Dukhopelnykov Department of Applied Mathematics V. N Karazin Kharkiv National University Kharkiv Ukraine Department of Information Engineering Computer Science and Mathematics University of L'Aquila L'Aquila Italy Department of Applied Mathematics V.N. Karazin Kharkiv National University Laboratory of Micro and Nano Optics and Institute of Radio-Physics and Electronics NASU Kharkiv Ukraine

ISBN: (纸本)9798350331530

We consider the antenna shaped as a spherical dielectric lens with a conformal graphene disk on its surface, fed with elementary source. The latter is a radial electric dipole placed on the lens rotation axis. The electrical properties of graphene are characterized with the aid of the Kubo formulas, which are based on the quantum-theory description. First, we cast the wave-scattering problem to the dual series equations for the field expansion in terms of the spherical harmonics. Then, using the static part analytical inversion with the aid of the Abel integral transform, we reduce the dual series equations to an infinite matrix equation of the Fredholm type with elements depending on the elementary functions. This procedure guarantees the convergence and enables us to accurately characterize the considered lens antenna performance, in particular, its radiation resistance and directivity, in the THz frequency range.

关键词： Resistance Codes Dipole antennas Surface waves Numerical analysis Graphene Resonant frequency

Ubiquitous Flat Bands in a Cr-based Kagome Superconductor

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arXiv 2024年

作者： Guo, Yucheng Wang, Zehao Xie, Fang Huang, Yuefei Gao, Bin Oh, Ji Seop Wu, Han Liu, Zhaoyu Ren, Zheng Fang, Yuan Biswas, Ananya Zhang, Yichen Yue, Ziqin Hu, Cheng Jozwiak, Chris Bostwick, Aaron Rotenberg, Eli Hashimoto, Makoto Lu, Donghui Kono, Junichiro Chu, Jiun-Haw Yakobson, Boris I. Birgeneau, Robert J. Si, Qimiao Dai, Pengcheng Yi, Ming Department of Physics and Astronomy Rice University HoustonTX77005 United States Advanced Light Source Lawrence Berkeley National Laboratory BerkeleyCA94720 United States Department of Materials Science and NanoEngineering Rice University HoustonTX77005 United States Department of Physics University of California BerkeleyCA94720 United States Department of Physics University of Washington Washington98105 United States Applied Physics Graduate Program Smalley-Curl Institute Rice University HoustonTX77005 United States Stanford Synchrotron Radiation Lightsource SLAC National Accelerator Laboratory Menlo ParkCA94025 United States Department of Electrical and Computer Engineering Rice University HoustonTX77005 United States Smalley-Curl Institute Rice University HoustonTX77005 United States Department of Materials Science and NanoEngineering Rice University HoustonTX77005 United States

In the quest for novel quantum states driven by topology and correlation, kagome lattice materials have garnered significant interest due to their distinctive electronic band structures, featuring flat bands (FBs) arising from the quantum destructive interference of the electronic wave function. The tuning of the FBs to the chemical potential would lead to the possibility of liberating electronic instabilities that lead to emergent electronic orders. Despite extensive studies, direct evidence of FBs tuned to the chemical potential and their participation in emergent electronic orders have been lacking in bulk quantum materials. Here using a combination of Angle-Resolved Photoemission Spectroscopy (ARPES) and Density Functional Theory (DFT), we reveal that the low-energy electronic structure of the recently discovered Cr-based kagome metal superconductor CsCr3Sb5 is dominated by a pervasive FB in close proximity to, and below the Fermi level. A comparative analysis with orbital-projected DFT and polarization dependence measurement uncovers that an orbital-selective renormalization mechanism is needed to reconcile the discrepancy with the DFT calculations, which predict the FB to appear 200 meV above the Fermi level. Furthermore, we observe the FB to shift away from the Fermi level by 20 meV in the low-temperature density wave-ordered phase, highlighting the role of the FB in the emergent electronic order. Our results reveal CsCr3Sb5 to stand out as a promising platform for further exploration into the effects of FBs near the Fermi level on kagome lattices, and their role in emergent orders in bulk quantum materials. © 2024, CC BY.

关键词： Density functional theory

Scientific Machine Learning Framework to Understand Flash Graphene Synthesis

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arXiv 2023年

作者： Sattari, Kianoosh Eddy, Lucas Beckham, Jacob L. Wyss, Kevin M. Byfield, Richard Qian, Long Tour, James M. Lin, Jian Department of Mechanical and Aerospace Engineering University of Missouri ColumbiaMO65211 United States Department of Chemistry 6100 Main Street HoustonTX77005 United States Applied Physics Program Smalley-Curl Institute 6100 Main Street HoustonTX77005 United States Department of Materials Science and NanoEngineering 6100 Main Street HoustonTX77005 United States Department of Computer Science and Engineering NanoCarbon Center The Welch Institute for Advanced Materials Rice University 6100 Main Street HoustonTX77005 United States

Flash Joule heating (FJH) is a far-from-equilibrium (FFE) processing method for converting low-value carbon-based materials to flash graphene (FG). Despite its promise in scalability and performance, attempts to explore the reaction mechanism have been limited due to complexity involved in the FFE process. Data-driven machine learning (ML) models effectively account for this complexity, but the model training requires considerable amount of experimental data. To tackle this challenge, we constructed a scientific ML (SML) framework trained by using both direct processing variables and indirect, physics-informed variables to predict the FG yield. The indirect variables include current-derived features (final current, maximum current, and charge density) predicted from the proxy ML models and reaction temperatures simulated from multi-physics modeling. With the combined indirect features, the final ML model achieves an average R2 score of 0.81 ± 0.05 and an average RMSE of 12.1% ± 2.0% in predicting the FG yield, which is significantly higher than the model trained without them (R2 of 0.73 ± 0.05 and an RMSE of 14.3% ± 2.0%). Feature importance analysis validates the key roles of these indirect features in determining the reaction outcome. These results illustrate the promise of this SML to elucidate FFE material synthesis outcomes, thus paving a new avenue to processing other datasets from the materials systems involving the same or different FFE processes. Copyright © 2023, The Authors. All rights reserved.

关键词： Graphene

Quantum communication through devices with indefinite input-output direction

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arXiv 2022年

作者： Liu, Zixuan Yang, Ming Chiribella, Giulio QICI Quantum Information and Computation Initiative Department of Computer Science The University of Hong Kong Pokfulam Road Hong Kong HKU-Oxford Joint Laboratory for Quantum Information and Computation Department of Applied Mathematics and Theoretical Physics Centre for Mathematical Sciences University of Cambridge Wilberforce Road CambridgeCB3 0WA United Kingdom Department of Computer Science University of Oxford Wolfson Building Parks Road Oxford United Kingdom HKU-Oxford Joint Laboratory for Quantum Information and Computation Perimeter Institute for Theoretical Physics 31 Caroline Street North WaterlooON Canada

Certain quantum devices, such as half-wave plates and quarter-wave plates in quantum optics, are bidirectional, meaning that the roles of their input and output ports can be exchanged. Bidirectional devices can be used in a forward mode and a backward mode, corresponding to two opposite choices of the input-output direction. They can also be used in a coherent superposition of the forward and backward modes, giving rise to new operations with indefinite input-output direction. In this work we explore the potential of input-output indefiniteness for the transfer of classical and quantum information through noisy channels. We first formulate a model of communication from a sender to a receiver via a noisy channel used in indefinite input-output direction. Then, we show that indefiniteness of the input-output direction yields advantages over standard communication protocols in which the given noisy channel is used in a fixed input-output direction. These advantages range from a general reduction of noise in bidirectional processes, to heralded noiseless transmission of quantum states, and, in some special cases, to a complete noise removal. The noise reduction due to input-output indefiniteness can be experimentally demonstrated with current photonic technologies, providing a way to investigate the operational consequences of exotic scenarios characterised by coherent quantum superpositions of forward-time and backward-time processes. Copyright © 2022, The Authors. All rights reserved.

关键词： Quantum optics

Hybrid Oscillator-Qubit Quantum Processors: Simulating Fermions, Bosons, and Gauge Fields

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arXiv 2024年

作者： Crane, Eleanor Smith, Kevin C. Tomesh, Teague Eickbusch, Alec Martyn, John M. Kühn, Stefan Funcke, Lena DeMarco, Michael Austin Chuang, Isaac L. Wiebe, Nathan Schuckert, Alexander Girvin, Steven M. Department of Physics Co-Design Center for Quantum Advantage Massachusetts Institute of Technology CambridgeMA02139 United States Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology CambridgeMA02139 United States Joint Quantum Institute Joint Center for Quantum Information and Computer Science University of Maryland NIST College ParkMD20742 United States Brookhaven National Laboratory UptonNY11973 United States Yale Quantum Institute PO Box 208 334 17 Hillhouse Ave New HavenCT06520-8263 United States Departments of Applied Physics and Physics Yale University New HavenCT06511 United States Department of Computer Science Princeton University PrincetonNJ08544 United States Infleqtion ChicagoIL60604 United States Center for Theoretical Physics Massachusetts Institute of Technology CambridgeMA02139 United States The NSF AI Institute for Artificial Intelligence and Fundamental Interactions CQTA Deutsches Elektronen-Synchrotron DESY Platanenallee 6 Zeuthen15738 Germany University of Bonn Nussallee 14-16 Bonn53115 Germany Department of Computer Science University of Toronto Canada Pacific Northwest National Laboratory RichlandWA United States Canadian Institute for Advanced Studies Toronto Canada

We develop a hybrid oscillator-qubit processor framework for quantum simulation of strongly correlated fermions and bosons that avoids the boson-to-qubit mapping overhead encountered in qubit hardware. This framework gives exact decompositions of particle interactions such as density-density terms and gauge-invariant hopping, as well as approximate methods based on the Baker-Campbell Hausdorff formulas including the magnetic field term for the U(1) quantum link model in (2 + 1)D. We use this framework to show how to simulate dynamics using Trotterisation, perform ancilla-free partial error detection using Gauss's law, measure non-local observables, estimate ground state energies using a oscillator-qubit variational quantum eigensolver as well as quantum signal processing, and we numerically study the influence of hardware errors in circuit QED experiments. To show the advantages over all-qubit hardware, we perform an end-to-end comparison of the gate complexity for the gauge-invariant hopping term and find an improvement of the asymptotic scaling with the boson number cutoff S from O(log(S)2) to O(1) in our framework as well as, for bosonic matter, a constant factor improvement of better than 104. We also find an improvement from O(log(S)) to O(1) for the U(1) magnetic field term. While our work focusses on an implementation in superconducting hardware, our framework can also be used in trapped ion, and neutral atom hardware. This work establishes digital quantum simulation with hybrid oscillator-qubit hardware as a viable and advantageous method for the study of qubit-boson models in materials science, chemistry, and high-energy physics. Copyright © 2024, The Authors. All rights reserved.

关键词： Ground state

Approximation algorithms for steiner tree based on star contractions: A unified view 15

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Approximation algorithms for steiner tree based on star cont...

15th International Symposium on Parameterized and Exact Computation, IPEC 2020

作者： Hušek, Radek Knop, Dušan Masařík, Tomáš Computer Science Institute of Charles University Faculty of Mathematics and Physics Charles University Prague Czech Republic Department of Theoretical Computer Science Faculty of Information Technology Czech Technical University in Prague Czech Republic Faculty of Mathematics Informatics and Mechanics University of Warsaw Poland Department of Applied Mathematics Faculty of Mathematics and Physics Charles University Czech Republic

ISBN: (纸本)9783959771726

In the Steiner Tree problem, we are given an edge-weighted undirected graph G = (V, E) and a set of terminals R ⊆ V . The task is to find a connected subgraph of G containing R and minimizing the sum of weights of its edges. Steiner Tree is well known to be NP-complete and is undoubtedly one of the most studied problems in (applied) computer science. We observe that many approximation algorithms for Steiner Tree follow a similar scheme (meta-algorithm) and perform (exhaustively) a similar routine which we call star contraction. Here, by a star contraction, we mean finding a star-like subgraph in (the metric closure of) the input graph minimizing the ratio of its weight to the number of contained terminals minus one;and contract. It is not hard to see that the well-known MST-approximation seeks the best star to contract among those containing two terminals only. Zelikovsky’s approximation algorithm follows a similar workflow, finding the best star among those containing three terminals. We perform an empirical study of star contractions with the relaxed condition on the number of terminals in each star contraction motivated by a recent result of Dvořák et al. [Parameterized Approximation Schemes for Steiner Trees with Small Number of Steiner Vertices, STACS 2018]. Furthermore, we propose two improvements of Zelikovsky’s 11/6-approximation algorithm and we empirically confirm that the quality of the solution returned by any of these is better than the one returned by the former algorithm. However, such an improvement is exchanged for a slower running time (up to a multiplicative factor of the number of terminals). © Radek Hušek, Dušan Knop, and Tomáš Masařík;licensed under Creative Commons License CC-BY

关键词： Stars