Azimuthal Equidistant Research Articles

EEG emotion recognition using EEG-SWTNS neural network through EEG spectral image

The rapid development in deep learning models provide considerable advancements in emotion recognition by electroencephalogram (EEG). However, existing approaches primarily focus on temporal and frequency domain features of EEG signals, neglecting spatial domain features in model information integration. Therefore, this study proposed a novel EEG input format, called EEG spectral image (ESI), which integrates spatial domain features using Azimuthal Equidistant Projection (AEP) and frequency domain features through differential entropy (DE). To better utilize this fine-grained data format, we propose the EEG Swin Transformer (EEG-SWTNS), which combines the window attention mechanism with shifted window partitioning. Window attention mechanism can concentrate on affective information within various regions and use shifted window partitioning to disrupt aggregated emotional representations for more granular features. Different from traditional graph neural networks, this method leverages the spatial locality of region information, leading to enhanced performance in EEG-based emotion recognition. Experiments conducted on SEED and SEED IV datasets demonstrate superior performance compared to baseline methods and the state-of-the-art models. Relative improvements of 0.6% and 0.08% are observed in subject-dependent experiments, while accuracies of 80.07% and 66.72% are achieved in subject-independent experiments without utilizing transfer learning techniques.

Desiderata for a Performative Hybrid Immersive Drawing Platform

Abstract We discuss the design requirements of a software platform for constructing immersive environments through handmade spherical perspective drawings in a performative setting, with concurrent interactive live feed of the spherical drawing’s VR visualization. We investigate current best practices and available software in order to extract functionalities, requirements, improvements, possible integrations and future developments. We map the base requirements of the software from three sources: the state of the art of drawing techniques for spherical perspectives (equirectangular, azimuthal equidistant and cubical), the available software for their practice and the experimentation with novel hybrid artefacts. For the latter, we use a node-based program that allows us to prototype the workflow before entering a pure coding stage. The desired software platform should integrate well within digital art practices, stimulate and facilitate the practice of anamorphic handmade spherical drawings, and expand spherical perspectives’ applications through the emerging media of Hybrid Immersive Models (HIMs).

Supervised domain generalization for integration of disparate scalp EEG datasets for automatic epileptic seizure detection

Numerous automatic epileptic seizure detectors (ESDs) with excellent performances have been reported, but they generally experience performance degradation when tested with real-life clinical data. This has been blamed on the scarcity of high-quality training data, which leads to models that generalize poorly. There is consequently interest in methods to improve the quality and quantity of training data for ESDs. This study used a domain generalization approach to combine data from two different datasets for training an ESD, which was thereafter tested on a third dataset. A subspace of the CHB-MIT and TUSZ scalp EEG seizure datasets was extracted using transfer component analysis, based on a reproducing kernel Hilbert space approach. We then used the Azimuthal Equidistant Projection to transform 3D electrode coordinates into 2D space, followed by interpolation using the Clough–Tocher technique to generate 16x16 rasters. We thereafter generated feature vectors, each of which was a sequence of 17 ten-layer 16x16 raster arrays. The vectors were used to train a recurrent-convolutional neural network. The network had a 128-unit long short-term memory layer with inputs from 17 parallel networks each with three stacks of convolutional layers. Testing was based on a private 26-subject dataset, combined with randomly selected subsets of the CHB-MIT and TUSZ datasets. A combined sensitivity of 74.5% was achieved, along with a false positive per hour rate of 0.84, and a latency of 2.32 s. Detection sensitivity on the private dataset was 72.5%. These results compare favorably with results of large-scale validation studies in literature and confirm the viability of this approach to increasing the size of training datasets for ESDs.

Reflections on the Projection of Ions in Atom Probe Tomography

There are two main projections used to transform, and reconstruct, field ion micrographs or atom probe tomography data into atomic coordinates at the specimen surface and, subsequently, in three dimensions. In this article, we present a perspective on the strength of the azimuthal equidistant projection in comparison with the more widely used and well-established point projection (or pseudo-stereographic projection), which underpins data reconstruction in most software packages currently in use across the community. After an overview of the reconstruction methodology, we demonstrate that the azimuthal equidistant is more robust with regards to errors on the parameters used to perform the reconstruction and is therefore more likely to yield more accurate tomographic reconstructions.

Representation of the World Ocean Floor by Azimuthal Equidistant Projection centred in Tokyo

Representation of the World Ocean Floor by Azimuthal Equidistant Projection centred in Tokyo

Tug of War at the Border

Rugby, North Dakota claims the distinction of being the geographic centre of North America. The author examines this claim and attempts to compute the true location of the geographic centre of North America. The author concludes that an iterative method based on the Lambert Azimuthal Equal Area (LAEA) projection, which slightly understates distance, and the Azimuthal Equidistant projection, which slightly overstates area, is the best method for computing the geographic centre of a given area. Six different definitions of North America are considered, and a proposed centre is offered for each definition.

“Magnifying-Glass” Azimuthal Map Projections

For maps focusing on a region of interest, but including surrounding areas to provide a setting, new azimuthal projections have been developed with a “magnifying-glass” effect. On two such projections, inside a circle bounding the region of interest is a standard Azimuthal Equidistant or Lambert Azimuthal Equal-Area projection. Between this circle and an outer bounding circle, azimuths remain true and the radial or area scale, respectively, remains constant, but at a reduced value. On four other projections, the inner portion is a standard azimuthal projection, which may be Stereographic, Gnomonic, or the above, but beyond this portion, the radial scale is gradually reduced to zero. Equivalents with rectangular boundaries are also available.

Notes on Two Projections

The development of projections with loxodromic properties is considered with regard to the azimuthal equidistant, and an example is given centred at 45°N, 0°E. The nature and value of the two-point equidistant projection is discussed and an example given centred on London and Wellington.

Notes on Two Projections

Abstract The development of projections with loxodromic properties is considered with regard to the azimuthal equidistant, and an example is given centred at 45°N, 0°E. The nature and value of the two-point equidistant projection is discussed and an example given centred on London and Wellington.

The Azimuthal Equidistant Projection

Pacific ViewpointVolume 6, Issue 2 p. 240-240 ArticleFree Access The Azimuthal Equidistant Projection D. R. Winchester, D. R. Winchester Victoria University of Wellington.Search for more papers by this author D. R. Winchester, D. R. Winchester Victoria University of Wellington.Search for more papers by this author First published: 01 May 1965 https://doi.org/10.1111/apv.62013AboutPDF ToolsExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume6, Issue2September 1965Pages 240-240 RelatedInformation

A CLASSIFICATION OF MAP PROJECTIONS1

THE desire for a classification of map projections stems from the fact that an infinite number of distinct projections are possible. Hence, the fundamental problem in classifying map projections is the partitioning of this infinite set into a comprehensible and useful finite number of all-inclusive and preferably non-overlapping classes. Several classifications of map projections are to be found in the cartographic literature. The advantages and disadvantages of each, of course, depend on the purpose, just as the properties by which classes are to be distinguished depend on the purpose. The classification based on geometric models (perspectivities) separating projections into conic, cylindric, planar, polyconic, polycylindric, etc., is convenient and is often used. The major shortcoming of this system is that it is not allinclusive. Another most important method of classification, based on the preservation of certain geometric properties of the surface of the referent object, separates the conformal projections from the equal-area projections, leaving a third class which is neither. Preservation of additional properties yields further classes; e.g., geodesic maps (for the sphere there is the gnomonic projection and all linear transforms thereof), azimuthal projections, equidistant projections (including polar isometries such as the azimuthal equidistant), and many more. In fact, Felix Klein, the German mathematician, defined a geometry as the study of properties preserved by a particular group of transformations. From this point of view, a classification according to properties preserved is the very essence of geometry. Thus one has projective transformations and projective geometry, affine transformations and affine geometry, Euclidean

A New Use for the Plate Carree Projection

D w URING and since World War II there has been an increasing use of the azimuthal equidistant projection for world maps, particularly maps of air routes. The azimuthal equidistant projection is by no means an innovation, however; since its invention by Guillaume Postel in I58i it has been used frequently. The usual forms of the projection are the North Polar and an oblique centered on a national capital London, Washington, Berlin, Moscow, and so on. Examples are noted in the Appendix. A great deal has been written on the subject of Air Age cartography, but the one thing that apparently has not been said of the azimuthal equidistant projection is that its properties are not unique, and that there is in fact another projection which is essentially both azimuthal and equidistant about a given point.' This is theplate carree, or simple cylindrical, the simplest of all projections, the graticule of which can be constructed merely by numbering the lines on a sheet of graph paper to represent meridians and parallels. Both the azimuthal equidistant and the plate carree are extreme cases of the simple conic projection, representing, respectively, the cone flattened out to a plane tangent to the sphere at latitude goo and the cone steepened into a cylinder tangent to the sphere along the equator. It is found that these related projections, like similar groups such as the stereographic, the Lambert conical orthomorphic, and the Mercator, have some common properties.2 On a polar azimuthal equidistant map the meridians are equispaced great circles radiating outward from one of the poles and the parallels are concentric distance circles that can be numbered from o? to i80?. On the plate carree or any other cylindrical projection these equispaced great-circle azimuths from the pole appear as equispaced parallel lines. The scale of longitude along the top and bottom edges of the normal case of a cylindrical projection indicates the azimuth from the projection pole of all places along each meridian. Similarly, the latitude scale along the left and right edges, if

Equal-Area Projections and the Azimuthal Equidistant Projection in Maps of Disease

Equal-Area Projections and the Azimuthal Equidistant Projection in Maps of Disease Affiliation Saul Jarcho CopyRight https://doi.org/10.2105/AJPH.35.10.1005 Published Online: August 29, 2011

Azimuthal Equidistant Projection of the Sphere

Azimuthal Equidistant Projection of the Sphere