What Hinders Accurate Depiction of Projective Shape?

Perception ◽  
1995 ◽  
Vol 24 (9) ◽  
pp. 995-1010 ◽  
Author(s):  
Emiel Reith ◽  
Chang Hong Liu
Keyword(s):  
Da Vinci ◽  
The Other ◽  
Frontoparallel Plane ◽  
Glass Pane ◽  
Drawing Task ◽  
Visual Projection ◽  
Vertical Glass ◽  
Perceptual Abilities ◽  
Improved Accuracy ◽  
Projective Shape

Adult subjects drew the visual projection of two models. One model was a trapezoid placed in the frontoparallel plane. The other was a tilted rectangle which displayed the same projective shape on a frontoparallel plane as the trapezoid. The drawing conditions were varied in two ways: the model remained available for inspection during the drawing task or it was masked after initial inspection; the subjects drew on paper placed flat on the table or on a vertical glass pane placed in front of the model (ie on a da Vinci window). The results were that (i) the projective shape of the frontoparallel trapezoid was reproduced accurately whereas that of the tilted rectangle was systematically distorted in the direction of its actual physical dimensions; (ii) when subjects drew on paper, the presence or absence of a view of the model made no difference to the amount of distortion; (iii) drawing on a da Vinci window improved accuracy even when the model was hidden. These findings provide information about the relative roles of object-centred knowledge, perceptual abilities, and depiction skills in drawing performance.

scholarly journals Deep spatio-temporal emotion analysis of geo-tagged tweets for predicting location based communal emotion during COVID-19 Lock-down

2021 ◽  
pp. 1-14
Author(s):  
M. Amsaprabhaa ◽  
Y. Nancy Jane ◽  
H. Khanna Nehemiah
Keyword(s):  
Latent Dirichlet Allocation ◽  
Temporal Analysis ◽  
The Other ◽  
Classification Model ◽  
Grid Search ◽  
Analysis Framework ◽  
Emotion Classification ◽  
Spatio Temporal ◽  
Improved Accuracy ◽  
State Of Art

Due to the COVID-19 pandemic, countries across the globe has enforced lockdown restrictions that influence the people’s socio-economic lifecycle. The objective of this paper is to predict the communal emotion of people from different locations during the COVID-19 lockdown. The proposed work aims in developing a deep spatio-temporal analysis framework of geo-tagged tweets to predict the emotions of different topics based on location. An optimized Latent Dirichlet Allocation (LDA) approach is presented for finding the optimal hyper-parameters using grid search. A multi-class emotion classification model is then built via a Recurrent Neural Network (RNN) to predict emotions for each topic based on locations. The proposed work is experimented with the twitter streaming API dataset. The experimental results prove that the presented LDA model-using grid search along with the RNN model for emotion classification outperforms the other state of art methods with an improved accuracy of 94.6%.

Specification of retinotectal connexions during development of the toad Xenopus laevis

Development ◽  
1980 ◽  
Vol 55 (1) ◽  
pp. 77-92
Author(s):  
S. C. Sharma ◽  
J. G. Hollyfield
Keyword(s):  
Xenopus Laevis ◽  
Ganglion Cell ◽  
Retinal Ganglion Cells ◽  
Optic Tectum ◽  
Ganglion Cells ◽  
The Other ◽  
Retinal Ganglion ◽  
Visual Projection ◽  
Series Of Experiments ◽  
The Right

The specification of central connexions of retinal ganglion cells was studied in Xenopus laevis. In one series of experiments, the right eye primordium was rotated 180° at embryonic stages 24–32. In the other series, the left eye was transplanted into the right orbit, and vice versa, with either 0° or 180° rotation. After metamorphosis the visual projections from the operated eye to the contralateral optic tectum were mapped electrophysiologically and compared with the normal retinotectal map. In all cases the visual projection map was rotated through the same angle as was indicated by the position of the choroidal fissure. The left eye exchanged into the right orbit retained its original axes and projected to the contralateral tectum. These results suggest that retinal ganglion cell connexions are specified before stage 24.

Mining Bug Report Repositories to Identify Significant Information for Software Bug Fixing

2021 ◽  
Author(s):  
Bancha Luaphol ◽  
Jantima Polpinij ◽  
Manasawee Kaenampornpan
Keyword(s):  
The Other ◽  
Problem Domain ◽  
Significant Information ◽  
Bug Reports ◽  
Bug Fixing ◽  
Classification Technique ◽  
Bug Report ◽  
Multiple Issues ◽  
Improved Accuracy ◽  
Software Bug

Most studies relating to bug reports aims to automatically identify necessary information from bug reports for software bug fixing. Unfortunately, the study of bug reports focuses only on one issue, but more complete and comprehensive software bug fixing would be facilitated by assessing multiple issues concurrently. This becomes a challenge in this study, where it aims to present a method of identifying bug reports at severe level from a bug report repository, together with assembling their related bug reports to visualize the overall picture of a software problem domain. The proposed method is called “mining bug report repositories”. Two techniques of text mining are applied as the main mechanisms in this method. First, classification is applied for identifying severe bug reports, called “bug severity classification”, while “threshold-based similarity analysis” is then applied to assemble bug reports that are related to a bug report at severe level. Our datasets are from three opensource namely SeaMonkey, Firefox, and Core:Layout downloaded from the Bugzilla. Finally, the best models from the proposed method are selected and compared with two baseline methods. For identifying severe bug reports using classification technique, the results show that our method improved accuracy, F1, and AUC scores over the baseline by 11.39, 11.63, and 19% respectively. Meanwhile, for assembling related bug reports using threshold-based similarity technique, the results show that our method improved precision, and likelihood scores over the other baseline by 15.76, and 9.14% respectively. This demonstrate that our proposed method may help increasing chance to fix bugs completely.

Differential Effects of D2- and D4-Blocking Neuroleptics on the Procedural Learning of Schizophrenic Patients

1996 ◽  
Vol 41 (7) ◽  
pp. S21-S24 ◽  
Author(s):  
Marc-André Bédard ◽  
Hélène Scherer ◽  
Julie Delorimier ◽  
Emmanuel Stip ◽  
Pierre Lalonde
Keyword(s):  
Procedural Learning ◽  
The Other ◽  
Differential Effects ◽  
Drawing Task ◽  
Schizophrenic Patients ◽  
Drug Naïve ◽  
Per Se ◽  
Learning Trials ◽  
Haloperidol Group ◽  
Better Than

Objective: To illustrate the differential effects of D2- and D4-blocking neuroleptics on the procedural learning of patients with schizophrenia. Method: Twenty-nine schizophrenic patients were divided into 3 groups according to their pharmacological treatment: 1) drug naive, 2) haloperidol, and 3) clozapine. They were all assessed on clinical and procedural measures, the latter being the mirror drawing task. Results: All groups showed progressive learning over the successive trials, and drug-naive patients performed better than the other groups. Patients in the haloperidol group showed many fluctuations over trials, suggesting difficulty in the progressive automation of the task. Such fluctuations did not occur in the clozapine group, but performances per se were worse than in the other groups during the learning trials. A utomation of the task occurred at the same point (second block of trials) for all groups. Conclusion: These results suggest that D2- and D4-blocking neuroleptics do not similarly affect striatal dependent procedural learning in schizophrenia.

scholarly journals Images and Theories

Nuncius ◽  
2018 ◽  
Vol 33 (3) ◽  
pp. 442-463
Author(s):  
Domenico Laurenza
Keyword(s):  
Early Modern ◽  
Microscopic Examination ◽  
Da Vinci ◽  
Leonardo Da Vinci ◽  
The Other ◽  
Analogical Model ◽  
Other Hand

Abstract The paper examines how images, technological-artistic knowledge and theories interacted with each other in early modern geology. Casting techniques provided Leonardo da Vinci (1452–1519) with an analogical model for the study of fossils, which he expounded using only texts and theories, not images. For painter Agostino Scilla, on the other hand, images of fossils and animals (La Vana speculazione disingannata dal senso, Napoli, 1670) were the key-feature of his approach, intentionally limited to the external aspects of the specimen, the very domain of the painter. Theories and microscopic examination of the internal aspects orientated Robert Hooke’s visual comparisons in Micrographia (London, 1665), aimed at demonstrating the organic origin of fossils, while, in the same period, visual comparisons were used to support opposite interpretations of fossils as well, like in the case of Francesco Stelluti.

scholarly journals A NanoSIMS 50 L Investigation into Improving the Precision and Accuracy of the 235U/238U Ratio Determination by Using the Molecular 235U16O and 238U16O Secondary Ions

Minerals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 307 ◽  
Author(s):  
N. Zirakparvar ◽  
Cole Hexel ◽  
Andrew Miskowiec ◽  
Julie Smith ◽  
Michael Ambrogio ◽  
...  
Keyword(s):  
Reference Materials ◽  
The Other ◽  
Primary Beam ◽  
Uranium Compounds ◽  
Accuracy And Precision ◽  
Secondary Ions ◽  
Precision And Accuracy ◽  
Improved Accuracy ◽  
Secondary Ion ◽  
238U Ratio

A NanoSIMS 50 L was used to study the relationship between the 235U/238U atomic and 235U16O/238U16O molecular uranium isotope ratios determined from a variety of uranium compounds (UO2, UO2F2, UO3, UO2(NO3)2·6(H2O), and UF4) and silicates (NIST-610 glass and the Plesovice zircon reference materials, both containing µg/g uranium). Because there is typically a greater abundance of 235U16O+ and 238U16O+ molecular secondary ions than 235U+ and 238U+ atomic ions when uranium-bearing materials are sputtered with an oxygen primary ion beam, the goal was to understand whether use of 235U16O/238U16O has the potential for improved accuracy and precision when compared to the 235U/238U ratio. The UO2 and silicate reference materials showed the greatest potential for improved accuracy and precision through use of the 235U16O/238U16O ratio as compared to the 235U/238U ratio. For the UO2, which was investigated at a variety of primary beam currents, and the silicate reference materials, which were only investigated using a single primary beam current, this improvement was especially pronounced at low 235U+ count rates. In contrast, comparison of the 235U16O/238U16O ratio versus the 235U/238U ratio from the other uranium compounds clearly indicates that the 235U16O/238U16O ratio results in worse precision and accuracy. This behavior is based on the observation that the atomic (235U+ and 238U+) to molecular (235U16O+ and 238U16O+) secondary ion production rates remain internally consistent within the UO2 and silicate reference materials, whereas it is highly variable in the other uranium compounds. Efforts to understand the origin of this behavior suggest that irregular sample surface topography, and/or molecular interferences arising from the manner in which the UO2F2, UO3, UO2(NO3)2·6(H2O), and UF4 were prepared, may be a major contributing factor to the inconsistent relationship between the observed atomic and molecular secondary ion yields. Overall, the results suggest that for certain bulk compositions, use of the 235U16O/238U16O may be a viable approach to improving the precision and accuracy in situations where a relatively low 235U+ count rate is expected.

Occlusion Constraints and Stereoscopic Slant

Perception ◽  
1997 ◽  
Vol 26 (1) ◽  
pp. 29-38 ◽  
Author(s):  
Jukka Häkkinen ◽  
Göte Nyman
Keyword(s):  
Binocular Vision ◽  
Retinal Image ◽  
Three Dimensional ◽  
Vertical Axis ◽  
The Other ◽  
Necessary Condition ◽  
Slant Perception ◽  
Frontoparallel Plane ◽  
Reduction Effect

In binocular vision horizontal magnification of one retinal image leads to a percept of three-dimensional slant around a vertical axis. It is demonstrated that the perception of slant is diminished when an occlusion interpretation is possible. A frontoparallel plane located in the immediate vicinity of a slanted surface in a location which allows a perception of occlusion reduces the magnitude of perceived slant significantly. When the same plane is placed on the other side, the slant perception is normal because there is no alternative occlusion interpretation. The results indicate that a common border between the occluder and a slanted surface is not a necessary condition for the reduction effect. If the edges are displaced and the edge of the slanted surface is placed in a location in which it could be occluded, the effect still appears.

Palaeoliths and Terraces near Bournemouth

1949 ◽  
Vol 15 ◽  
pp. 21-37 ◽  
Author(s):  
J. Bernard Calkin ◽  
J. F. N. Green
Keyword(s):  
The Other ◽  
Archaeological Evidence ◽  
Critical Areas ◽  
Other Hand ◽  
Exact Position ◽  
The Subject ◽  
Improved Accuracy

Upwards of three thousand palaeolithic implements are known to have been obtained from gravels within 8 miles of Bournemouth. The largest proportion, probably a majority, come from the gravels of the 130-ft. terrace which constitutes the greater part of the ‘Palaeolithic Terrace’ of Reid (1) and is correlated with the Boyn Hill terrace of the Thames. Most of the less rolled of these belong to Middle Acheulian types, especially Acheul III of Breuil, and, though their exact position is rarely known, the correspondence is so usual that the gravels of this terrace near Bournemouth have been dated by them with some confidence.On the other hand the palaeolithic dating of other terraces has been the subject of some doubt. Recently the terraces have been mapped on the six-inch scale and their morphology measured with improved accuracy (2). It is the object of this paper to record some further implements from the local gravels, and in the light of the latest geological and archaeological evidence, to date the gravels in two critical areas, as a step towards more complete chronology here and elsewhere.

Monocular Discs in the Occlusion Zones of Binocular Surfaces Do Not Have Quantitative Depth—A Comparison with Panum's Limiting Case

Perception ◽  
10.1068/p3456 ◽  
2003 ◽  
Vol 32 (8) ◽  
pp. 1009-1019 ◽  
Author(s):  
Barbara Gillam ◽  
Michael Cook ◽  
Shane Blackburn
Keyword(s):  
Da Vinci ◽  
Critical Factor ◽  
The Other ◽  
Apparent Depth ◽  
Supporting Evidence ◽  
Lateral Separation ◽  
Minimum Depth ◽  
New Form ◽  
Contralateral Eye ◽  
Limiting Case

Da Vinci stereopsis is defined as apparent depth seen in a monocular object laterally adjacent to a binocular surface in a position consistent with its occlusion by the other eye. It is widely regarded as a new form of quantitative stereopsis because the depth seen is quantitatively related to the lateral separation of the monocular element and the binocular surface (Nakayama and Shimojo 1990 Vision Research30 1811–1825). This can be predicted on the basis that the more separated the monocular element is from the surface the greater its minimum depth behind the surface would have to be to account for its monocular occlusion. Supporting evidence, however, has used narrow bars as the monocular elements, raising the possibility that quantitative depth as a function of separation could be attributable to Panum's limiting case (double fusion) rather than to a new form of stereopsis. We compared the depth performance of monocular objects fusible with the edge of the surface in the contralateral eye (lines) and non-fusible objects (disks) and found that, although the fusible objects showed highly quantitative depth, the disks did not, appearing behind the surface to the same degree at all separations from it. These findings indicate that, although there is a crude sense of depth for discrete monocular objects placed in a valid position for uniocular occlusion, depth is not quantitative. They also indicate that Panum's limiting case is not, as has sometimes been claimed, itself a case of da Vinci stereopsis since fusibility is a critical factor for seeing quantitative depth in discrete monocular objects relative to a binocular surface.

Highly similar and competing visual scenes lead to diminished object but not spatial detail in memory drawings

2021 ◽  
Author(s):  
Elizabeth Hall ◽  
Wilma A. Bainbridge ◽  
Chris Ian Baker
Keyword(s):  
Spatial Memory ◽  
Spatial Information ◽  
The Other ◽  
Movement Behavior ◽  
Prior Work ◽  
Original Image ◽  
Complex Scene ◽  
Specific Detail ◽  
Memory Accuracy ◽  
Drawing Task

Drawings of scenes made from memory can be highly detailed and spatially accurate, with little information not found in the observed stimuli. While prior work has focused on studying memory for distinct scenes, less is known about the specific detail recalled when episodes are highly similar and competing. Here, participants (N=30) were asked to study and recall eight complex scene images using a drawing task. Importantly, four of these images were exemplars of different scene categories, while the other four images were from the same scene category. The resulting 213 drawings were judged by 1,764 online scorers for a comprehensive set of measures, including scene and object diagnosticity, spatial information, and fixation and pen movement behavior. We observed that competition in memory resulted in diminished object detail, with drawings and objects that were less diagnostic of their original image. However, repeated exemplars of a category did not result in differences in spatial memory accuracy, and there were no differences in fixations during study or pen movements during recall. These results reveal that while drawings for distinct categories of scenes can be highly detailed and accurate, drawings for scenes from repeated categories, creating competition in memory, show reduced object detail.

Sign in / Sign up

Export Citation Format

Share Document