vertical velocity
Assessment of Developmental Dysgraphia Utilising a Display Tablet
Mekyska, Jiri, Galaz, Zoltan, Safarova, Katarina, Zvoncak, Vojtech, Cunek, Lukas, Urbanek, Tomas, Havigerova, Jana Marie, Bednarova, Jirina, Mucha, Jan, Gavenciak, Michal, Smekal, Zdenek, Faundez-Zanuy, Marcos
Even though the computerised assessment of developmental dysgraphia (DD) based on online handwriting processing has increasing popularity, most of the solutions are based on a setup, where a child writes on a paper fixed to a digitizing tablet that is connected to a computer. Although this approach enables the standard way of writing using an inking pen, it is difficult to be administered by children themselves. The main goal of this study is thus to explore, whether the quantitative analysis of online handwriting recorded via a display/screen tablet could sufficiently support the assessment of DD as well. For the purpose of this study, we enrolled 144 children (attending the 3rd and 4th class of a primary school), whose handwriting proficiency was assessed by a special education counsellor, and who assessed themselves by the Handwriting Proficiency Screening Questionnaires for Children (HPSQ-C). Using machine learning models based on a gradient-boosting algorithm, we were able to support the DD diagnosis with up to 83.6 % accuracy. The HPSQ-C total score was estimated with a minimum error equal to 10.34 %. Children with DD spent significantly higher time in-air, they had a higher number of pen elevations, a bigger height of on-surface strokes, a lower in-air tempo, and a higher variation in the angular velocity. Although this study shows a promising impact of DD assessment via display tablets, it also accents the fact that modelling of subjective scores is challenging and a complex and data-driven quantification of DD manifestations is needed. This study was supported by a project of the Technology Agency of the Czech Republic no.
- Europe > Czechia > South Moravian Region > Brno (0.04)
- North America > United States > Minnesota > Olmsted County > Rochester (0.04)
- Europe > Spain > Catalonia > Barcelona Province > Barcelona (0.04)
- Research Report > Experimental Study (1.00)
- Research Report > New Finding (0.93)
- Health & Medicine > Therapeutic Area > Neurology (0.46)
- Education > Focused Education > Special Education (0.35)
- Education > Educational Setting > K-12 Education > Primary School (0.34)
Machine Learning Estimation of Maximum Vertical Velocity from Radar
Chase, Randy J., McGovern, Amy, Homeyer, Cameron, Marinescu, Peter, Potvin, Corey
The quantification of storm updrafts remains unavailable for operational forecasting despite their inherent importance to convection and its associated severe weather hazards. Updraft proxies, like overshooting top area from satellite images, have been linked to severe weather hazards but only relate to a limited portion of the total storm updraft. This study investigates if a machine learning model, namely U-Nets, can skillfully retrieve maximum vertical velocity and its areal extent from 3-dimensional gridded radar reflectivity alone. The machine learning model is trained using simulated radar reflectivity and vertical velocity from the National Severe Storm Laboratory's convection permitting Warn on Forecast System (WoFS). A parametric regression technique using the sinh-arcsinh-normal distribution is adapted to run with U-Nets, allowing for both deterministic and probabilistic predictions of maximum vertical velocity. The best models after hyperparameter search provided less than 50% root mean squared error, a coefficient of determination greater than 0.65 and an intersection over union (IoU) of more than 0.45 on the independent test set composed of WoFS data. Beyond the WoFS analysis, a case study was conducted using real radar data and corresponding dual-Doppler analyses of vertical velocity within a supercell. The U-Net consistently underestimates the dual-Doppler updraft speed estimates by 50$\%$. Meanwhile, the area of the 5 and 10 m s^-1 updraft cores show an IoU of 0.25. While the above statistics are not exceptional, the machine learning model enables quick distillation of 3D radar data that is related to the maximum vertical velocity which could be useful in assessing a storm's severe potential.
- North America > United States > Oklahoma > Cleveland County > Norman (0.28)
- North America > Canada > Alberta (0.14)
- North America > United States > Texas > Carson County > Panhandle (0.04)
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On some limitations of data-driven weather forecasting models
As in many other areas of engineering and applied science, Machine Learning (ML) is having a profound impact in the domain of Weather and Climate Prediction. A very recent development in this area has been the emergence of fully data-driven ML prediction models which routinely claim superior performance to that of traditional physics-based models. In this work, we examine some aspects of the forecasts produced by an exemplar of the current generation of ML models, Pangu-Weather, with a focus on the fidelity and physical consistency of those forecasts and how these characteristics relate to perceived forecast performance. The main conclusion is that Pangu-Weather forecasts, and possibly those of similar ML models, do not have the fidelity and physical consistency of physics-based models and their advantage in accuracy on traditional deterministic metrics of forecast skill can be at least partly attributed to these peculiarities. Balancing forecast skill and physical consistency of ML-driven predictions will be an important consideration for future ML models. However, and similarly to other modern post-processing technologies, the current ML models appear to be already able to add value to standard NWP output for specific forecast applications and combined with their extremely low computational cost during deployment, are set to provide an additional, useful source of forecast information. .
- North America > United States > New York (0.04)
- Europe > United Kingdom > England > Cambridgeshire > Cambridge (0.04)
- Europe > United Kingdom > England > Berkshire > Reading (0.04)
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- Research Report (0.50)
- Instructional Material (0.46)
New AI Model Revealed Turbulence Hiding in The Sun's Atmosphere
Japan's AI research team developed a new AI model which can detect and predict the hidden turbulent motions taking place inside the sun's atmosphere. The data was collected from the surface of the solar photosphere. It is the surface of the sun and it's considered the lowest layer of the solar atmosphere and the region in which solar activity such as sunspots, solar flares, and coronal mass ejections originate. The new AI model could correctly identify turbulent horizontal motion below the surface. This could help us to better understand solar convection, and processes that generate explosions and jets erupting from the sun.
Let's-a-Go: The Physics of Jumping in Super Mario Run
Of course I'm not the first to look at the physics in Super Mario Bros--there was this interesting paper looking at the optimal jump to get to the highest point on the flag at the end of the level. There is also a nice page looking at the acceleration of jumping Mario in the different games. This is a great chance to take another look at the physics of Mario. The best way to get data from a video game is to first capture the action and then use video analysis. With video analysis, I can get position-time data by looking at the location of the object in each frame.