Computer science pedagogy has overwhelmingly favored problem-solving practice over methods of engagement like worked-out example study especially in advanced classes. This is due to the belief that ...while these alternative methods may improve student conceptual learning, they may leave them less able to perform on authentic problem-solving tasks from a lack of hands-on practice. In this paper, we perform a direct comparison of this trade-off in a synchronous collaborative programming project by adjusting the boundary between problem-solving and collaborative reflection based on a worked-out example while keeping the total time on task constant. We find that the more time students spent on worked example study, the more was the observed improvement in the pre- to post-test scores with no significant difference in performance on a subsequent problem-solving task. These results, therefore, challenge the dominant place of problem-solving practice in the advanced curricular context and inform the design of collaborative programming projects at scale.
Contributing to the literature on aptitude-treatment interactions between worked examples and problem-solving, this paper addresses differential learning from the two approaches when students are ...positioned as domain experts learning new concepts. Our evaluation is situated in a team project that is part of an advanced software engineering course. In this course, students who possess foundational domain knowledge but are learning new concepts engage alternatively in programming followed by worked example-based reflection. They are either allowed to finish programming or are curtailed after a pre-specified time to participate in a longer worked example-based reflection. We find significant pre- to post-test learning gains in both conditions. Then, we not only find significantly more learning when students participated in longer worked example-based reflections but also a significant performance improvement on a problem-solving transfer task. These findings suggest that domain experts learning new concepts benefit more from worked example-based reflections than from problem-solving.
The electronic computer has brought about a mathematical revolution in the second half of the twentieth century. Once forbidding calculations are now within the reach of the average student and ...techniques which before had only theoretical interest have been seen to have practical value too. This book combines some of the familiar results and applications of calculus with the new language of the computer. The student using this book will need a solid background in high school algebra, an understanding of what a function is and how to draw its graph, and a beginning knowledge of computer programming. The book is designed to be used in several ways: as a supplement for students who have completed a course in elementary functions, as an introduction to a calculus course, or as outside reading in a liberal arts mathematics course. The four chapters use mathematics to describe and explain some observations about the growth of population. Each chapter is accompanied by a set of exercises which range from routine calculations to suggested projects. Exercises marked with an asterisk are more difficult. The computer programs included in the book are written in BASIC. (Author/TK)
DESC DC2 Data Release Note LSST Dark Energy Science Collaboration; Abolfathi, Bela; Armstrong, Robert ...
arXiv.org,
06/2022
Paper, Journal Article
Odprti dostop
In preparation for cosmological analyses of the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST), the LSST Dark Energy Science Collaboration (LSST DESC) has created a 300 deg\(^2\) ...simulated survey as part of an effort called Data Challenge 2 (DC2). The DC2 simulated sky survey, in six optical bands with observations following a reference LSST observing cadence, was processed with the LSST Science Pipelines (19.0.0). In this Note, we describe the public data release of the resulting object catalogs for the coadded images of five years of simulated observations along with associated truth catalogs. We include a brief description of the major features of the available data sets. To enable convenient access to the data products, we have developed a web portal connected to Globus data services. We describe how to access the data and provide example Jupyter Notebooks in Python to aid first interactions with the data. We welcome feedback and questions about the data release via a GitHub repository.
The LSST DESC DC2 Simulated Sky Survey LSST Dark Energy Science Collaboration; Abolfathi, Bela; Alonso, David ...
arXiv.org,
01/2021
Paper, Journal Article
Odprti dostop
We describe the simulated sky survey underlying the second data challenge (DC2) carried out in preparation for analysis of the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) by the ...LSST Dark Energy Science Collaboration (LSST DESC). Significant connections across multiple science domains will be a hallmark of LSST; the DC2 program represents a unique modeling effort that stresses this interconnectivity in a way that has not been attempted before. This effort encompasses a full end-to-end approach: starting from a large N-body simulation, through setting up LSST-like observations including realistic cadences, through image simulations, and finally processing with Rubin's LSST Science Pipelines. This last step ensures that we generate data products resembling those to be delivered by the Rubin Observatory as closely as is currently possible. The simulated DC2 sky survey covers six optical bands in a wide-fast-deep (WFD) area of approximately 300 deg^2 as well as a deep drilling field (DDF) of approximately 1 deg^2. We simulate 5 years of the planned 10-year survey. The DC2 sky survey has multiple purposes. First, the LSST DESC working groups can use the dataset to develop a range of DESC analysis pipelines to prepare for the advent of actual data. Second, it serves as a realistic testbed for the image processing software under development for LSST by the Rubin Observatory. In particular, simulated data provide a controlled way to investigate certain image-level systematic effects. Finally, the DC2 sky survey enables the exploration of new scientific ideas in both static and time-domain cosmology.
We construct all six-element orders which are not 50%-tolerance orders. We show that a width-two order is a 50% tolerance order if and only if no restriction of the order to a six-element set is ...isomorphic to one of these six-element orders. This yields a corresponding characterization of bipartite 50%-tolerance graphs. Since an order (graph) has a 50% tolerance representation if and only if it has a unit tolerance representation, our results apply to unit tolerance orders (graphs) as well.
We have successfully demonstrated a series of results that push the limits of optical sensing, acceleration sensing and lithography. We previously built some of the most sensitive displacement ...sensors with displacement sensitivities as low as 12 fm/√Hz at 1 kHz. Using reference detection circuitry in conjunction with correlated double sampling methods, we have lowered the 1/f noise floor to 10 milli-Hz, hence improving the detection limit at low frequencies (10 milli-Hz) from 37 pm/√Hz to 50 fm/√Hz i.e. by 57.3 dB. We have developed the capability to convert these highly sensitive displacement sensors to highly sensitive acceleration sensors through innovative low-stress mass addition and direct mass integration processes. We have built accelerometers with resonant frequencies as low as 43 Hz and thermal noise floors as low as 10 nG/√Hz. We have pushed the limits of shaker table experiments to verify direct acceleration measurements as low as 10 μG/radicHz.
We describe the results of two placebo-controlled trials (MIL-1077 and MIL-1078) designed to evaluate the clinical efficacy of oral milrinone administered together with converting enzyme inhibitors ...to patients with congestive heart failure. Although these trials were terminated prematurely, they provide the only controlled data regarding the effect of oral milrinone on exercise capacity in patients receiving converting enzyme inhibitors. Of the 254 patients randomized, 140 completed one of the trials or reached an end point and are the basis of this report. In both trials, there was a clear trend for an increase in exercise capacity in the milrinone-treated patients (+ 26 ± 8% vs. +5 ± 7% in MIL-1077 and + 11 ± 5% vs. + 2 ± 4% in MIL-1078). Symptoms of congestive heart failure were decreased in one trial but not the other. Quality of life, as assessed by a questionnaire, was not effected in either trial. There was an increased incidence of adverse events in milrinone-treated patients. Adverse events related primarily to hypotension and vasodilation led to discontinuation of drug in 18 milrinone-treated patients vs. 1 placebo-treated patient. Milrinone had little or no proarrhythmic effect and cardiovascular deaths were distributed equally between the milrinone and placebo groups. These data suggest that when used in combination with a converting enzyme inhibitor, oral milrinone improves exercise capacity but is associated with a high incidence of adverse events that appear to be related to excessive vasodilation.
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