In this paper, a system for rendering voxel (3D pixel)-based worlds is presented. The system enables the generation of such worlds from LiDAR and orthophoto data by discretizing LiDAR data with a ...resolution of 1 m. In world generation, the embedded basic semantic descriptors of LiDAR data are used, enhanced with additional classes acquired from colour information in geospatially aligned orthophoto images. The system allows local use as well as web-based use and supports multi-core and multi-processor hardware, as well as the clustering of multiple instances for faster rendering. We also present the results (renderings of selected areas) and describe other possible uses of the presented system.
Self-regulated learning (SRL) plays an important role in successful learning with hypertexts. The use of appropriate SRL strategies helps students acquire new knowledge more efficiently. We ...investigated the use of SRL strategies in individual learning from expository science hypertext, the correlations between different measures of self-regulation, and the differences in SRL between more and less successful students. A sample of 443 ninth graders from 15 different schools participated in the study. A variety of off- and online measures were used to measure SRL. Data were collected from student traces, questionnaires, tests scores, and notes. Low correlations between the off- and online measures of SRL suggest that they measure different aspects of SRL use in learning digital science texts. Student achievement in science positively correlated with their use of SRL strategies. Students with higher knowledge gains reported the higher use of deep cognitive strategies, higher motivation for learning, and used a higher number of strategies in note-taking while learning. The results of this study may have practical implications for teachers to support student SRL and for developers of digital learning materials to incorporate SRL scaffolding into learning topics.
Several studies dealing with music recommendation and visualization base their approaches on datasets gathered with user surveys. However, the gathering procedure is seldom the focus of music ...research, even though the user interfaces and methodology are an important part of gathering the music data and evaluation of the music information retrieval algorithms. The paper presents the main elements of gathering the Moodo dataset that combines the demographic data, the users' mood and perception of emotions with the users' emotional and color responses to music. For this purpose, two novel user interfaces were developed, i.e. the MoodStripe and MoodGraph, which have several advantages over the existing classical models, both in terms of intuitiveness and functionality. The proposed interfaces are also applicable to other domains dealing with the user data.
Several studies dealing with music recommendation and visualization base their approaches on datasets gathered with user surveys. However, the gathering procedure is seldom the focus of music ...research, even though the user interfaces and methodology are an important part of gathering the music data and evaluation of the music information retrieval algorithms. The paper presents the main elements of gathering the Moodo dataset that combines the demographic data, the users' mood and perception of emotions with the users' emotional and color responses to music. For this purpose, two novel user interfaces were developed, i.e. the MoodStripe and MoodGraph, which have several advantages over the existing classical models, both in terms of intuitiveness and functionality. The proposed interfaces are also applicable to other domains dealing with the user data.
The Golgi apparatus (GA) is a cellular organelle involved in the processing and sorting of proteins in eukaryotic cells. Due to its numerous functions, structural complexity, and organizational ...dynamics, the role of the GA in normal and pathological processes is still under intensive research. In this work, we present an approach to automatic segmentation of the GA in electron microscopy volumetric data, consisting of i) a neural network trained on approximately labelled data, ii) active contours for refining the segmentation, and iii) filtering of the segmented regions. Evaluation on 3D volumes of a urinary bladder epithelial cell shows that the proposed algorithm is able to segment the GA with 89% sensitivity and 99% specificity. Using approximate labels reduced the time needed for manual annotation of the ground truth by a factor of five.
Depth perception in volumetric visualization plays a crucial role in the understanding and interpretation of volumetric data. Numerous visualization techniques, many of which rely on physically based ...optical effects, promise to improve depth perception but often do so without considering camera movement or the content of the volume. As a result, the findings from previous studies may not be directly applicable to crowded volumes, where a large number of contained structures disrupts spatial perception. Crowded volumes therefore require special analysis and visualization tools with sparsification capabilities. Interactivity is an integral part of visualizing and exploring crowded spaces, but has received little attention in previous studies. To address this gap, we conducted a study to assess the impact of different rendering techniques on depth perception in crowded volumes, with a particular focus on the effects of camera movement. The results show that depth perception considering camera motion depends much more on the content of the volume than on the chosen visualization technique. Furthermore, we found that traditional rendering techniques, which have often performed poorly in previous studies, showed comparable performance to physically based methods in our study.
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