3,111 research outputs found
HIGH SCHOOL MATHEMATICS TEACHERS’ VIEWS ON COMPUTER-ASSISTED MATHEMATICS INSTRUCTION THROUGH COMPUTER ALGEBRA SYSTEMS IN TURKEY
In this paper, high school mathematics teachers’ views on computer-assisted mathematics instruction and on computer algebra systems (CAS) were explored in two stages, before and after they were trained on it. This study is based on the case study model of the qualitative research method. Semi-structured interview forms constitute the data of the study. Some codes and themes were established with the descriptive and content analyses of the data. The results show that teachers had positive opinions about computer-assisted mathematics instruction before they were trained, yet a majority of them was not able to use it in their classes for several reasons. However, it is seen that none of the teachers except for one knew about computer algebra systems (CAS). It is understood after the training that all the teachers wanted to use computer-assisted mathematics instruction in their classes, and thus they needed to use Mathematica, which is a computer algebra system, during the process. Likewise, while most of the teachers did not want their students to interact with computers or tablets in their classes before the computer-assisted mathematics instruction training, almost all of them had a favorable opinion of it after the training.  Article visualizations
Modellus: Learning Physics with Mathematical Modelling
Tese de doutoramento em Ciências da Educação, área de Teoria Curricular e Ensino das CiênciasComputers are now a major tool in research and development in almost all scientific
and technological fields. Despite recent developments, this is far from true for learning
environments in schools and most undergraduate studies.
This thesis proposes a framework for designing curricula where computers, and
computer modelling in particular, are a major tool for learning. The framework, based on
research on learning science and mathematics and on computer user interface, assumes
that: 1) learning is an active process of creating meaning from representations; 2)
learning takes place in a community of practice where students learn both from their own
effort and from external guidance; 3) learning is a process of becoming familiar with
concepts, with links between concepts, and with representations; 4) direct manipulation
user interfaces allow students to explore concrete-abstract objects such as those of
physics and can be used by students with minimal computer knowledge
Toward a Systematic Evidence-Base for Science in Out-of-School Time: The Role of Assessment
Analyzes the tools used in assessments of afterschool and summer science programs, explores the need for comprehensive tools for comparisons across programs, and discusses the most effective structure and format for such a tool. Includes recommendations
A Systematic Literature Review on Advances in Computer Assisted Instruction
The use of multimedia as a tool for delivering learning content instead of the traditional classroom learning practice is gaining popularity nowadays. CAI is the use of computer programs that are available both online and offline for instruction. The objective of this paper is to conduct a systematic literature review (SLR) on computer assisted (or aided) instruction (CAI) for five years period from 2018 to 2022. This SLR uses review protocol for the selection of primary studies for inclusion in the study from the pool of literature available in the research community. The results of the review shows that the highest publication on CAI in the review period was in 2020 and most researchers used achievement test for collection of data on CAI in the reviewed period. The study also found out that ‘Computer-Based Simulation’ is the popular type of CAI used in experiments by researchers in the period of review. The use of CAI for teaching and learning activities enables flexible and efficient interaction among students and educators. This is a critical factor for enhancing learners’ academic achievement. In conclusion, it is recommended that further research be conducted on CAI to promote its adoption in education systems
Energy and Charge Transfer in Organic Materials and Its Spectroscopic Signature: An Ab Initio Approach
Energy and charge transfer processes in organic materials have received a tremendous amount of attention in recent years, due to their impact on functionality within a wide range of applications. One prominent example is the field of organic photovoltaics (OPVs), where significant improvements in power conversion efficiency and durability have been achieved over the last decade. Another example is organic scintillators, which have seen a renewed interest due to the constrained supply of helium–3 gas, as well as their ability to discriminate between types of ionizing radiation. Advancement in the design of organic photovoltaic and luminescent materials can be facilitated by molecular level insights into the processes of energy transfer, gained through both experimental observations and theoretical and computational modeling. Thus, this thesis utilizes computational techniques to investigate excited states, and their spectroscopic signatures, in molecular systems that are experimentally relevant for OPVs and organic scintillators.
In Chapter II of this thesis, a computational protocol based on density functional theory (DFT) is presented for calculating the dependence of the vibrational frequency of a carbonyl reporter mode on the electronic state of the molecular system, in the context of charge transfer (CT) in organic molecules. This protocol was utilized to study a system consisting of a phenyl–C61–butyric acid methyl ester electron acceptor with a N,N–dimethylaniline donor, in which small frequency shifts of less than 4 cm−1 were observed between the ground state and the CT excited state. A Stark tuning rate of 0.768 cm−1/(MV/cm) was calculated between the vibrational frequency and the electric field.
In Chapter III of this thesis, the CT process in a carotenoid–porphyrin–C60 molecular triad was investigated in its two primary conformations (bent/linear) with an explicit tetrahydrofuran solvent via molecular dynamics. Vibrational frequency distributions were calculated for the amide I mode and found to be sensitive to the three electronic states relevant to CT: the Pi–Pi* excited state, the porphyrin-to-C60 CT state, and the carotenoid-to-C60 charge-separated state, with shifts as large as 40–60 cm−1 observed between the CT1 and CT2 states. Rate constants between these states were calculated with a hierarchy of approximations based on the linearized semiclassical method. The CT process was determined to occur via a two-step mechanism, Pi–Pi* -> CT1 -> CT2, where the second step is mediated by the bent-to-linear conformation change.
In Chapter IV of this thesis, the role of intersystem crossing (ISC) from S1 to Tn in the pulse-shape discrimination (PSD) ability of single-crystal trans–stilbene was investigated. Time-dependent DFT was used with the newly developed OT– SRSH–PCM method to calculate the excited states, and an equilibrium Fermi’s golden rule approach was employed to calculate transition rate constants. The ISC rates were found to be too slow to compete with prompt fluorescence, and thus do not significantly impact the PSD ability. Deuteration of trans–stilbene was found to have a retarding effect on the ISC rates, with rate constants reduced by as much as 30%.
Finally, in Chapter V of this thesis, a novel compute-to-learn pedagogy is presented, in which students design and develop interactive demonstrations of physical chemistry concepts in a peer-led studio environment. The rationale behind the pedagogy and improvements made over the course of three iterations are discussed, as well as an initial assessment of the pedagogy conducted via end-of-semester interviews.PHDChemistryUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/147569/1/klwill_1.pd
Viewpoints: A high-performance high-dimensional exploratory data analysis tool
Scientific data sets continue to increase in both size and complexity. In the
past, dedicated graphics systems at supercomputing centers were required to
visualize large data sets, but as the price of commodity graphics hardware has
dropped and its capability has increased, it is now possible, in principle, to
view large complex data sets on a single workstation. To do this in practice,
an investigator will need software that is written to take advantage of the
relevant graphics hardware. The Viewpoints visualization package described
herein is an example of such software. Viewpoints is an interactive tool for
exploratory visual analysis of large, high-dimensional (multivariate) data. It
leverages the capabilities of modern graphics boards (GPUs) to run on a single
workstation or laptop. Viewpoints is minimalist: it attempts to do a small set
of useful things very well (or at least very quickly) in comparison with
similar packages today. Its basic feature set includes linked scatter plots
with brushing, dynamic histograms, normalization and outlier detection/removal.
Viewpoints was originally designed for astrophysicists, but it has since been
used in a variety of fields that range from astronomy, quantum chemistry, fluid
dynamics, machine learning, bioinformatics, and finance to information
technology server log mining. In this article, we describe the Viewpoints
package and show examples of its usage.Comment: 18 pages, 3 figures, PASP in press, this version corresponds more
closely to that to be publishe
Simulation modelling and visualisation: toolkits for building artificial worlds
Simulations users at all levels make heavy use of compute resources to drive computational
simulations for greatly varying applications areas of research using different simulation
paradigms. Simulations are implemented in many software forms, ranging from highly standardised
and general models that run in proprietary software packages to ad hoc hand-crafted
simulations codes for very specific applications. Visualisation of the workings or results of a
simulation is another highly valuable capability for simulation developers and practitioners.
There are many different software libraries and methods available for creating a visualisation
layer for simulations, and it is often a difficult and time-consuming process to assemble a
toolkit of these libraries and other resources that best suits a particular simulation model. We
present here a break-down of the main simulation paradigms, and discuss differing toolkits and
approaches that different researchers have taken to tackle coupled simulation and visualisation
in each paradigm
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