3,012 results on '"MAP projection"'
Search Results
2. Harmonized Landsat and Sentinel-2 Data with Google Earth Engine.
- Author
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Berra, Elias Fernando, Fontana, Denise Cybis, Yin, Feng, and Breunig, Fabio Marcelo
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NORMALIZED difference vegetation index , *ZONING , *TIME series analysis , *MAP projection , *LANDSAT satellites - Abstract
Continuous and dense time series of satellite remote sensing data are needed for several land monitoring applications, including vegetation phenology, in-season crop assessments, and improving land use and land cover classification. Supporting such applications at medium to high spatial resolution may be challenging with a single optical satellite sensor, as the frequency of good-quality observations can be low. To optimize good-quality data availability, some studies propose harmonized databases. This work aims at developing an 'all-in-one' Google Earth Engine (GEE) web-based workflow to produce harmonized surface reflectance data from Landsat-7 (L7) ETM+, Landsat-8 (L8) OLI, and Sentinel-2 (S2) MSI top of atmosphere (TOA) reflectance data. Six major processing steps to generate a new source of near-daily Harmonized Landsat and Sentinel (HLS) reflectance observations at 30 m spatial resolution are proposed and described: band adjustment, atmospheric correction, cloud and cloud shadow masking, view and illumination angle adjustment, co-registration, and reprojection and resampling. The HLS is applied to six equivalent spectral bands, resulting in a surface nadir BRDF-adjusted reflectance (NBAR) time series gridded to a common pixel resolution, map projection, and spatial extent. The spectrally corresponding bands and derived Normalized Difference Vegetation Index (NDVI) were compared, and their sensor differences were quantified by regression analyses. Examples of HLS time series are presented for two potential applications: agricultural and forest phenology. The HLS product is also validated against ground measurements of NDVI, achieving very similar temporal trajectories and magnitude of values (R2 = 0.98). The workflow and script presented in this work may be useful for the scientific community aiming at taking advantage of multi-sensor harmonized time series of optical data. [ABSTRACT FROM AUTHOR]
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- 2024
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3. Digital twins and deep maps.
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Kitchin, Rob and Dawkins, Oliver
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DIGITAL twins , *DIGITAL maps , *DIGITAL mapping , *URBAN renewal , *MAP projection - Abstract
Mapping is now thoroughly digital at all stages of production and maps are widely used in digital form. This digital turn has transformed the nature of mapping and maps. Maps need no longer be static representations, but rather constitute spatial media, providing an interactive, dynamic means for creating, discussing, and sharing spatial information and mediating spatial practices. This has included the development of 3D mapping, including nascent digital twins and digital deep maps. In this short paper, we reflect on our attempts to produce a 3D city information model for Dublin that acts as a basic digital twin, which we have also used to explore deep mapping, as well as map projecting data onto a printed 3D map model of the city. We consider what digital twins and deep maps mean for how we understand the nature of mapping, arguing that they produce a dyadic intertwining of map and territory; a literal, material expression of post‐representational, ontogenetic conceptions of mapping. [ABSTRACT FROM AUTHOR]
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- 2024
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4. A Low-Distortion Oblique Map Projection of the World's Landmasses.
- Author
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Kerkovits, Krisztián
- Subjects
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MAP projection , *POLYNOMIAL approximation , *HORSE paces, gaits, etc. , *MAPS , *SET-valued maps - Abstract
This study presents the development of a world map projection intended to minimize distortion of all continents. I begin by reviewing a very similar map projection developed by Canters (2002), and address its shortcomings by carefully fine-tuning the initial constraints and the method of optimization, while retaining the most useful ideas of this earlier map. Most notably, the method described in this paper puts a great emphasis on the outline of the map, so that its aesthetics make it more suitable for atlases; the method also exclusively uses reproducible, deterministic methods. Finally, I compare the resulting world map to the original one of Canters in terms of map distortions and practical usefulness. The method presented here should work without changes if a low-distortion map of any other global-scale area is needed. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Bringing ethics to cartography and geographic information science: AutoCarto 2022.
- Author
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Yao, Angela, Madden, Marguerite, Buckley, Aileen, Delmelle, Eric, and Sinha, Gaurav
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DIGITAL mapping , *GRAPH neural networks , *GEOGRAPHIC information systems , *MAP projection , *MAP design , *DEEP learning , *SOCIAL media - Abstract
The AutoCarto 2022 symposium centered around the theme of "Ethics in Mapping: Integrity, Inclusion, and Empathy." The conference brought together experts in cartography and geographic information science (GIScience) to explore the ethical responsibilities in these fields. The conference featured sessions on topics such as the power of maps for equity and social justice, uncertainty in geospatial data, and diversity, ethics, and equality. A special issue of the conference included papers on societal impacts and ethical issues, cartographic design and map production, and technical advancements in cartography. The document also discusses the future of the conference series and potential research directions in the field. [Extracted from the article]
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- 2024
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6. Cognition and perception of map projections: a literature review.
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Kessler, Fritz C. and Battersby, Sarah E.
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MAP projection , *LITERATURE reviews , *GEOGRAPHICAL perception , *ALTERNATIVE education , *SCHOLARLY publishing - Abstract
This paper explores scholarly literature published since the 1960s that examines peoples' cognitive and perceptual understanding of map projections. Map projections present challenges to virtually everyone who uses them. Some of the challenges include selecting a projection, specifying projection parameters, and understanding distortion patterns. Broadly speaking, cartographic inquiry has addressed many topics in cognition and perception; yet, research focused on projections remains scarce. We surveyed the body of research studies incorporating projections or a projection-related topic (e.g. distortion) as a variable in the experimental design. Topics included asking participants to estimate areas, conceptualize travel paths, or identify preferred graticule aesthetics. Despite the conclusions reported by these studies, we noted three general concerns that may diminish the accuracy of results from research in this area. First, projection-specific terminology or properties critical to the studies and analysis that may be misunderstood by researchers and/or participants. Second, study participants were largely homogenous. Third, most of the studies were not designed for replication or reproducibility. Given our critique, we offer six suggestions for those who are interested in new cognitive and perceptual projection research. [ABSTRACT FROM AUTHOR]
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- 2024
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7. EL “ARTE” DEL MÁRMOL: UNA APROXIMACIÓN ARQUEOLÓGICA Y DIGITAL A LAS SERRERÍAS HIDRÁULICAS DEL SIGLO XIX EN EL VALLE DEL ALMANZORA (ALMERÍA, ESPAÑA).
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Carreño Soler, José Javier, Maldonado Ruiz, Alexis, and Rouco Collazo, Jorge
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EXPERIMENTAL archaeology ,DRONE aircraft ,TEST design ,VIRTUAL work ,DIGITAL technology ,ARCHAEOLOGY ,MAP projection ,MARBLE - Abstract
Copyright of Virtual Archaeology Review is the property of Virtual Archaeology Review and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2024
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8. ASK ASTRO.
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Bond, Howard E., Shubinski, Raymond, Scoles, Sarah, and Kunimoto, Michelle
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STARS , *TRAVEL time (Traffic engineering) , *STAR maps (Astronomy) , *INTERPLANETARY dust , *MAP projection , *CONSTELLATIONS - Abstract
This article from Astronomy magazine features a Q&A section where experts answer questions about various astronomical topics. The first question addresses the phenomenon of superluminal expansion, specifically in relation to a light echo observed around the star V838 Monocerotis. The experts explain that the apparent growth of the dust ring around the star is an illusion caused by the extra distance traveled by the reflected light. The second question discusses the different ways constellations are depicted in astronomy software and books. The experts explain that the depiction of constellations has evolved over time, with different mapmakers and atlases using their own artistic interpretations. The third question explores how scientists identify the spectral lines of different compounds. The experts explain that each element and compound emits unique sets of wavelengths of light, allowing astronomers to identify their presence. The fingerprints of these chemicals are obtained through laboratory experiments, where the atoms are subjected to various conditions and their resulting light is analyzed. The final question compares the capabilities of the Transiting Exoplanet Survey Satellite (TESS) and the Kepler mission in discovering planets. The experts explain that TESS has a larger survey area, covering almost the entire sky, which allows it to observe a significantly larger pool of stars. TESS also operates for a longer period of time compared to Kepler. Both missions have contributed to our understanding of exoplanetary systems in different ways. [Extracted from the article]
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- 2024
9. Errors in the Introduction of Isometric Coordinates and Violation of the Property of Conformality of the Triaxial Ellipsoid Projections.
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Fleis, Maria E., Nyrtsov, Maxim V., Sokolov, Anton I., and Stooke, Philip J.
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MAP projection , *GRIDS (Cartography) , *ELLIPSOIDS , *ISOMETRICS (Mathematics) , *COORDINATES - Abstract
The purpose of this study is to show that some coordinate systems previously described as isometric are in fact not isometric, and as a consequence, map projections derived from them do not show the expected characteristics, especially conformality. Definitions and methods of the mathematical theory of surfaces are used. The article discusses two methods of specifying coordinate systems on the surface of the triaxial ellipsoid, erroneously called isometric. A consistent mathematical study of each of them based on the initial definition of isometric coordinates showed that in the first method, the corresponding coordinate system is not orthogonal, much less isometric. In the second method, the coordinates are determined using integration, and the result of the integration depends on the path of this integration. This ambiguity shows that this method is also incorrect. The considered coordinate systems allow the creation of new projections, but these projections are not conformal. As a result of the study, errors in determining isometric coordinates were shown and proven, which in earlier studies led to a violation of the properties of projections. This analysis should lead to the development of truly conformal projections of triaxial ellipsoids. For clarity maps and cartographic grids are presented. [ABSTRACT FROM AUTHOR]
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- 2024
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10. Web Publication of Schmitt's Map of Southern Germany (1797)—The Projection of the Map Based on Archival Documents and Geospatial Analysis.
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Timár, Gábor and Kiss, Eszter
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MAP projection , *GRIDS (Cartography) , *MAPS , *EIGHTEENTH century , *TRIANGULATION , *GEOSPATIAL data - Abstract
This work shows the original projection of a 1:57,600 scale map of southern Germany at the end of the 18th century, produced under the direction of Karl-Heinrich von Schmitt (1743–1805). The sections of the map were scanned and georeferenced as part of the MAPIRE project, and the results are publicly available. In the present work, we use contemporary documents, in particular the books of César-Francois Cassini de Thury and manuscript sketches of the map found in the Military Archive of Vienna, to show that the overall projection of the map is identical to that used in Cassini's survey of France (first half of the 18th century). In the archive, we managed to find the overview sheet on which—in addition to the Paris Cassini coordinate system—the section grid of the Schmitt map was also constructed. This sketch served as the basis for the compilation and copying work, wherein the existing map works and survey sketches were inserted into 197 sections of the Schmitt map. Thus, the map coordinate system can be modeled in GIS systems using the Cassini (or Cassini-Soldner) projection, with the Paris Observatory as the projection origin. The georeferencing accuracy of using the pure Cassini projection is around 1–1.3 km (at the extremes, around 5 km), which is much more inaccurate than the one used in later topographic surveys. It is considered a combined result of the compilation of the different maps, presumably surveyed by graphic triangulation with measuring tables. [ABSTRACT FROM AUTHOR]
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- 2024
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11. Jupiter in 2022 & 2023: Part II: The Juno mission & the Galilean moons.
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Rogers, John
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JUPITER (Planet) , *NATURAL satellites , *VOLCANIC plumes , *CALDERAS , *MAP projection - Abstract
This article provides an overview of the Juno mission and its observations of Jupiter's Galilean moons. The Juno spacecraft continues to send high-quality images of Jupiter, with a focus on the South Temperate Belt (STB) and the evolution of cyclonic spots within it. The article discusses the valuable insights gained from the images captured by JunoCam, including the changing pattern of images as Juno's orbit evolves. The text also discusses the close flybys of Jupiter's moon, Io, and the high-resolution images of its surface, revealing volcanic calderas and mountains. The impact of Jupiter's radiation belts on the spacecraft's camera is mentioned, along with the successful resolution of image degradation issues. [Extracted from the article]
- Published
- 2024
12. α-Latrotoxin Tetramers Spontaneously Form Two-Dimensional Crystals in Solution and Coordinated Multi-Pore Assemblies in Biological Membranes.
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Rohou, Alexis, Morris, Edward P., Makarova, Julia, Tonevitsky, Alexander G., and Ushkaryov, Yuri A.
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BIOLOGICAL membranes , *CRYSTALS , *MONODISPERSE colloids , *MAP projection , *UNIT cell , *IMAGE analysis - Abstract
α-Latrotoxin (α-LTX) was found to form two-dimensional (2D) monolayer arrays in solution at relatively low concentrations (0.1 mg/mL), with the toxin tetramer constituting a unit cell. The crystals were imaged using cryogenic electron microscopy (cryoEM), and image analysis yielded a ~12 Å projection map. At this resolution, no major conformational changes between the crystalline and solution states of α-LTX tetramers were observed. Electrophysiological studies showed that, under the conditions of crystallization, α-LTX simultaneously formed multiple channels in biological membranes that displayed coordinated gating. Two types of channels with conductance levels of 120 and 208 pS were identified. Furthermore, we observed two distinct tetramer conformations of tetramers both when observed as monodisperse single particles and within the 2D crystals, with pore diameters of 11 and 13.5 Å, suggestive of a flickering pore in the middle of the tetramer, which may correspond to the two states of toxin channels with different conductance levels. We discuss the structural changes that occur in α-LTX tetramers in solution and propose a mechanism of α-LTX insertion into the membrane. The propensity of α-LTX tetramers to form 2D crystals may explain many features of α-LTX toxicology and suggest that other pore-forming toxins may also form arrays of channels to exert maximal toxic effect. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Nonabelianness of fundamental group of flat spacetime.
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Agrawal, Gunjan and Deepanshi
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MINKOWSKI space , *SPACETIME , *MAP projection - Abstract
In the present paper, it has been obtained that the fundamental group of n -dimensional Minkowski space with the time topology contains uncountably many copies of the additive group of integers and is not abelian. The result has been first proved for n = 2. Thereafter, it is extended to n > 2 by proving that loops nonhomotopic in M 2 continue to be nonhomotopic in Mn using embedding of M 2 in Mn as a retract through the projection map. [ABSTRACT FROM AUTHOR]
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- 2024
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14. Hoozue: Indigenous Japanese Technique for Preservation of the Legacy Katsura Tree at Dumbarton Oaks.
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HENDERSON, Ron and KAVALIER, Jonathan
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TRADITIONAL knowledge ,MASTER gardeners ,TREES ,INDIGENOUS peoples ,MAP projection ,GARDEN design - Abstract
The katsura tree at Dumbarton Oaks is among the oldest of the species in North America and pre-dates the design of the garden. Japanese master gardener Kurato Fujimoto was commissioned to inspect and lead the construction and installation of a series of branch supports, known as "hoozue" in Japan, to rejuvenate this venerable tree that was in decline. The assessment of the tree included the inspection of the branch structure with a projection toward post-installation growth over the next several decades. Materials such as rope, bark fabric, nails (kasugai), and the wooden hoozue themselves were fabricated and installed with indigenous knowledge and experience, which were described in the text and drawings and documented in a series of photographic sequences. This article narrates the process of this preservation work, demonstrating the significance of this indigenous Japanese technique. [ABSTRACT FROM AUTHOR]
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- 2024
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15. Detection and Tracking Method for Multiple Moving Objects in Panoramic Video.
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LIU Huitong, WANG Xi, LIU Wei, and YANG Peng
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SPHERICAL projection ,MAP projection ,VIDEOS ,ARTIFICIAL satellite tracking - Abstract
The general solution of detection and tracking technology in panoramic videos is to detect and track moving objects after converting 360° video into two-dimensional video by projection. However, the fixed spherical projection will lead to discontinuous projection boundaries in panoramic videos. When a moving object is at a projection boundary, conventional spherical projection methods may divide the object into multiple parts, resulting in the missed or false detection. A multi-motion object detection and tracking method in panoramic video combining equi-rectangular projection (ERP) and cube map projection (CMP) is proposed. It uses suitable CMP stitching frames to reduce the polar distortion and compensate for the discontinuity of projection boundaries of ERP frames, solving the detection of objects at projection boundaries or polar distortion. Then, multi-motion object tracking is solved by fusing multiple features of perceptual hashing, spherical centroid and motion direction. Experimental results show that the proposed scheme can effectively alleviate the false detection caused by discontinuous projection boundaries and correctly track moving objects with occlusion, frame boundary shuttle or polar distortion. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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16. Testing the Mercator Effect: Global Map Projections Persuade Differently According to the Emphasis Frames Used to Contextualize Them.
- Author
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Richards, Adam S., Cooley, Evan, Miller, Jalen, and Watterson, Ronald
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MAP projection , *NATIONAL security , *FRAMES (Social sciences) - Abstract
This study assessed how global map projections affect perceptions of the importance of world regions and beliefs about geopolitical events. We tested whether the Mercator projection, which represents polar regions as being larger than their actual landmass, compared to the Gall-Peters projection, an equal-area map that represents landmass proportionately, alters evaluations of the U.S.' proposal to purchase Greenland. In a 2 (map projection: Mercator vs. Gall-Peters) × 2 (emphasis frame: economic vs. national security) experiment, we found that people attributed greater importance to Russia after viewing the Mercator projection only when the arguments paired with the map adopted a national security frame. This perception mediated effects of the experimental interaction on attitude toward, support for, and perceived ethics of the purchase. [ABSTRACT FROM AUTHOR]
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- 2024
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17. Connection of Conic and Cylindrical Map Projections.
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Lapaine, Miljenko
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MAP projection , *LIMITS (Mathematics) - Abstract
In previous papers that have dealt with cylindrical map projections as limiting cases of conical projections, standard or equidistant parallels were used in the derivations. This paper shows that this is not necessary and that it is sufficient to use parallels that preserve length. In addition, unlike other approaches, in this article the limiting cases of conic projections are derived in the most natural way, by deriving the equations of cylindrical projections from the equations of conic projections in a rectangular system in the projection plane using a mathematical concept of limits. It is shown that such an approach is possible, but not always, so it should be used carefully, or even better, avoided in teaching and studying map projections. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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18. Combining error models to reduce the imprecision of geometric length measurement in vector databases.
- Author
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Girres, Jean‐François
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LENGTH measurement , *MEASUREMENT errors , *MAP projection , *MANUFACTURING processes , *DATABASES - Abstract
Length measurements calculated from the geometry of vector geographic objects, called geometric measurements, are inherently imprecise. The imprecision of the measurements is due to the accumulation of causes of various origins, related to the production processes, and the rules of data representation. In order to reduce the overall imprecision of geometric length measurements, this article proposes to identify the causes of measurement error in the data, to model their respective impact, and finally to combine these different impacts. To do so, five causes of geometric measurement error have been modeled: map projection, terrain disregard, polygonal approximation of curves, digitizing error, and cartographic generalization. To estimate the overall measurement imprecision, three combination methods are proposed: selection of the maximum error, sum of the errors, and quadratic aggregation of the errors. An experiment conducted on a sample of roads represented at a medium scale demonstrates that quadratic error aggregation is the most effective combination method for reducing the imprecision of geometric length measurements. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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19. Study and application of deeply optimized neural network in roof stability evaluation.
- Author
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Yin, Huiyong, Li, Shuo, Xu, Guoliang, Xie, Daolei, Jiang, Cheng, Dong, Fangying, Wang, Houchen, and Wu, Bin
- Subjects
- *
COAL mining , *GRAPHICAL projection , *SEARCH algorithms , *SCIENTIFIC method , *MAP projection , *GEOLOGICAL research , *HYDROGEOLOGY - Abstract
Deep coal seam mining causes instability and collapse of coal seam roof frequently, which seriously affects the safety production and threatens the personal safety of underground personnel. In order to evaluate the stability of coal roof accurately, this paper select 6th coal seam in Kongduigou Coalfield of Jungar Coalfieldas research object, analyzes the geological and hydrogeological data, and study the lithology, rock combination, sandstone thickness, fault, fold, seam inclination, rock quality index, and rock compressive strength on the influence of the roof stability, drawing the main control factor 3D mapping projection surface maps. Select 58 borehole data points as the input samples (50 training sets and 8 test sets), use genetic algorithm (GA) to optimize the network random initial weights and threshold initial and sparrow search algorithm (SSA) for secondary optimization for the BP neural network training and learning, establishing GA-BP neural network based on SSA optimization (SSA-GA-BP neural network) coal roof stability evaluation model, which is used to predict and evaluate the 6th coal roof stability of the research area after the training error accuracy reached the requirements. The fuzzy comprehensive evaluation method, BP neural network, GA-BP neural network and SSA-GA-BP neural network are also used to predict and evaluate the 6th coal roof stability. Compare the evaluation results of each model with the actual value. The results show that the error of coal seam roof stability evaluation of SSA-GA-BP neural network is smallest, with the accuracy 88%, and the model is successfully applied to predict the roof stability of the 6th coal seam in Kongduigou Coalfield, which provides a scientific evaluation method and theoretical basis for the evaluation of coal seam roof stability. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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20. Rekonstruktion einer Vortragssituation Eduard Liesegangs Lichtbildserie „Unsere Kolonien".
- Author
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Mihr, Maximilian August am
- Subjects
MERGERS & acquisitions ,COLONIAL administration ,GERMAN colonies ,POSTCOLONIALISM ,MANUFACTURING industries ,MAP projection ,LIBRARY associations - Abstract
Copyright of Rundbrief Fotografie is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2024
- Full Text
- View/download PDF
21. Vision-based driver ear recognition and spatial reconstruction.
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Peng, Cheng, Liu, Jiang, Jiang, Tao, and Zhang, Xilong
- Subjects
SPATIAL orientation ,NOISE control ,EAR ,MAP projection ,TRAFFIC noise ,QUALITY control - Abstract
How to identify the ear hole more accurately and more quickly are critical for the active noise reduction in the road vehicle. Obscurations, causing by the long hair, the earphone, and some kind of caps, make the spatial location and orientation of the driver's ears almost impossible. To solve these two problems, a new method was proposed to replace the original image scaling detection by combining the Haar-like algorithm with the scale size of the variable detection window in the recognition process. A depth positioning camera is added to the ear recognition, which may offer more accurate point vectors for the driver's two ear holes. A simplified spatial reconstruction model was developed to assist the search when the piercing was occluded. After calculating the image-camera-cab projection mapping relationship, only four feature points are enough for the model's data requirement. The test results show that the detection Frame Per Second (FPS) was improved to 8.8, and the ear hole's positioning error is less than 0.1 cm. The proposed system can locate ear holes even with 100% obscurations. The research may have potential application as a front-end subsystem for the active noise reduction and voice interaction systems, improving the quality of acoustic control in cars. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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22. Effective fusion module with dilation convolution for monocular panoramic depth estimate.
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Han, Cheng, Cai, Yongqing, Pan, Xinpeng, and Wang, Ziyun
- Subjects
- *
MONOCULARS , *STEREO image processing , *VIRTUAL reality , *MAP projection , *SHARED virtual environments , *CONVOLUTION codes - Abstract
Depth estimation from monocular panoramic image is a crucial step in 3D reconstruction, which is a close relationship with virtual reality and metaverse technologies. In recent years, some methods, such as HRDFuse, BiFuse++, and UniFuse, have employed a two‐branch neural network leveraging two common projections: equirectangular and cubemap projections (CMPs). The equirectangular projection (ERP) provides a complete field of view but introduces distortion, while the CMP avoids distortion but introduces discontinuity at the boundary of the cube. In order to address the issue of distortion and discontinuity, the authors propose an efficient depth estimation fusion module to balance the feature mapping of the two projections. Moreover, for the ERP, the authors propose a novel inflated network architecture to extend the receptive field and effectively harness visual information. Extensive experiments show that the authors' method predicts more clear boundaries and accurate depth results while outperforming mainstream panoramic depth estimation algorithms. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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23. Distortion Effect on the UHPC Box Girder with Vertical Webs: Theoretical Analysis and Case Study.
- Author
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Wang, Chenguang, Wu, Yaowen, Zhang, Yuanhai, Tang, Shiying, Li, Weiwen, Wang, Peng, and Mansour, Walid
- Subjects
- *
BOX beams , *CONCRETE beams , *FINITE element method , *BENDING moment , *MAP projection - Abstract
Distortion deformation usually imposes a potential threat to bridge safety. In order to comprehensively understand the distortion effect on thin-walled ultra-high performance concrete (UHPC) box girders, an innovative approach encompassing the governing distortion differential equation is introduced in this study based on the general definition of distortion angle within the cross-section plane. The analytical results obtained from the proposed method are in accordance with those obtained from the energy method, and exhibit favorable agreement with experimental findings documented in the existing literature. Furthermore, a finite element model is developed on the ANSYS 2021 R1 software platform with the employment of a Shell 63 element. Numerical outcomes are also in good agreement with the experimental data, affirming the validity and reliability of the findings. In addition, parameter analysis results indicate that the distortion angle remains approximately constant at a location approximately 1/10 of the span from the mid-span cross-section of the box girder, regardless of changes in the span-to-depth ratio. Increasing the web thickness yields a notable reduction in the distortion effects, and decreasing the wall thickness can effectively mitigate the distortion-induced transverse bending moment. Compared with normal-strength concrete box girders, UHPC box girders can reduce the distortion angle within the span range, which is beneficial for maintaining the overall stability of the box girders. The outcomes obtained from this study yield engineers an enhanced understanding of distortion effect on the UHPC girder performance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
24. High-throughput mapping of single-neuron projection and molecular features by retrograde barcoded labeling.
- Author
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Peibo Xu, Jian Peng, Tingli Yuan, Zhaoqin Chen, Hui He, Ziyan Wu, Ting Li, Xiaodong Li, Luyue Wang, Le Gao, Jun Yan, Wu Wei, Li, Chengyu T., Zhen-Ge Luo, and Yuejun Chen
- Subjects
- *
MAP projection , *NEURAL circuitry , *HYPOTHALAMUS , *PREFRONTAL cortex , *TRANSCRIPTOMES , *GENE expression - Abstract
Deciphering patterns of connectivity between neurons in the brain is a critical step toward understanding brain function. Imaging-based neuroanatomical tracing identifies area-to-area or sparse neuron-to-neuron connectivity patterns, but with limited throughput. Barcode-based connectomics maps large numbers of single-neuron projections, but remains a challenge for jointly analyzing single-cell transcriptomics. Here, we established a rAAV2-retro barcode-based multiplexed tracing method that simultaneously characterizes the projectome and transcriptome at the single neuron level. We uncovered dedicated and collateral projection patterns of ventromedial prefrontal cortex (vmPFC) neurons to five downstream targets and found that projection-defined vmPFC neurons are molecularly heterogeneous. We identified transcriptional signatures of projection-specific vmPFC neurons, and verified Pou3f1 as a marker gene enriched in neurons projecting to the lateral hypothalamus, denoting a distinct subset with collateral projections to both dorsomedial striatum and lateral hypothalamus. In summary, we have developed a new multiplexed technique whose paired connectome and gene expression data can help reveal organizational principles that form neural circuits and process information. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
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25. K-theory of multiparameter persistence modules: Additivity.
- Author
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Grady, Ryan and Schenfisch, Anna
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- *
MAP projection , *K-theory - Abstract
Persistence modules stratify their underlying parameter space, a quality that makes persistence modules amenable to study via invariants of stratified spaces. In this article, we extend a result previously known only for one-parameter persistence modules to grid multiparameter persistence modules. Namely, we show the K-theory of grid multiparameter persistence modules is additive over strata. This is true for both standard monotone multi-parameter persistence as well as multiparameter notions of zig-zag persistence. We compare our calculations for the specific group K_0 with the recent work of Botnan, Oppermann, and Oudot, highlighting and explaining the differences between our results through an explicit projection map between computed groups. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
26. A problem in 'Basic Cartography'.
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Lapaine, Miljenko
- Abstract
In cartographic literature, map projections are usually interpreted as mapping to auxiliary development surfaces, and then these surfaces are developed into a plane. The so-called secant projections, i.e. projections in which the auxiliary surface intersects the Earth's sphere or ellipsoid are especially emphasized. It is stated and taken as a fact without proof that the parallels in which the auxiliary surface intersects the sphere are mapped without distortions. An example of such an approach is the publication Basic Cartography, published several years ago by the International Cartographic Association. This paper proves that standard parallels and secant parallels generally do not match. It turns out that the widely accepted facts about secant and standard parallels, which can also be found even in the most recent literature, are wrong and need to be revised. The paper concludes that explaining cylindrical projections as mapping on a cylindrical surface is not a good approach, because it leads to misunderstanding important properties of projection. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
27. Determining the scale and map projection of Stjepan Glavač's map from 1673.
- Author
-
Viličić, Marina and Lapaine, Miljenko
- Abstract
The uniqueness and detail in the depiction of Croatian regions gives Glavač's map exceptional importance as part of the Croatian cultural heritage. Since Glavač left behind as written evidence of map creation only its title and an exhaustive dedication, other information about the map remains unknown. The appearance of the cartographic network indicates that it is a normal aspect of cylindrical projection. From the relationship between the coordinates from the map, we concluded that Glavač used the equidistant cylindrical projection with the equator as a standard parallel. After that we have calculated that the ratio of the radius of the Earth's sphere to the scale of the map is 2292.7. The numerical scale of the map can be determined from a graphical scale and from the calculated ratio of the radius to the map scale. Since there were several attempts to determine the Earth's dimensions at the time of Glavač's map, there are several possible radii of the Earth's sphere. At the end of the paper, calculating the interval of the numerical scale of the map enabled us to refute and/or accept the theses of other authors who cited different scales of Glavač's map in their works. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
28. On auxiliary latitudes.
- Author
-
Karney, Charles F. F.
- Subjects
- *
MAP projection , *CARTOGRAPHY - Abstract
The auxiliary latitudes are essential tools in cartography. This paper summarizes methods for converting between them with an emphasis on providing full double-precision accuracy. This includes series expansions in the third flattening, where the truncation error is precisely measured and where estimates of the radii of convergence are given. Also new formulas are given for computing the rectifying and authalic latitudes with minimal roundoff error. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
29. Triangulation of the Earth's surface and its application to the geodetic velocity field modelling.
- Author
-
Berk, Sandi
- Subjects
- *
SURFACE of the earth , *TRIANGULATION , *SIMPLEX algorithm , *VELOCITY , *STRUCTURAL geology , *GEODETIC techniques , *MAP projection - Abstract
The Earth's crust is exposed by tectonic processes and is not static over time. Modelling of the Earth's surface velocities is of utmost importance for research in geodesy, geophysics, structural geology, and other geosciences. It may support positioning, navigation, seismic risk, and volcano notification services, for example. Space geodetic techniques can be used to provide high-quality velocities in a network of geodetic sites. Velocity field modelling should, however, expand the velocities from a discrete set of points to any location in-between. This paper presents four new methods for the Earth's surface velocity interpolation. Contrary to the widely used approach dividing the velocity field to the horizontal and vertical components, a full 3D interpolation approach is proposed based on the Delaunay triangulation and the n-simplex interpolation. The use of a combination of all three components is advantageous for geophysical interpretation. The proposed interpolation approach is entirely local but enables global modelling, which does not suffer from map projection distortions and singularities at the poles. Various global and regional position/velocity datasets are used to evaluate the performance of the proposed velocity interpolation methods. The latter provide practically the same results when applied to regional velocity field modelling. However, the so-called continuous piecewise quasi-radial 3D velocity field interpolation method is recommended for its favourable properties. It introduces an ellipsoidal Earth model, appropriately considers vertical/up and horizontal velocity components, tends to radial symmetry, and provides continuity for the interpolated velocity components as well as for the estimated uncertainties. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
30. Parallels in Cartography: Standard, Equidistantly Mapped and True Length Parallels.
- Author
-
Lapaine, Miljenko
- Subjects
- *
CARTOGRAPHY , *MAP projection , *LATITUDE , *MAPS - Abstract
In the literature on map projections, we regularly encounter the name standard parallel or standard parallels. However, it is obvious that a unique definition of a standard parallel is not universally accepted. To fully clarify the meaning of standard parallels, the author proposes the notion of equidistantly mapped parallels, which has not been common in the literature so far. Equidistantly mapped parallels can be in the direction of the parallel or in the direction of the meridian. Here, it is shown that every standard parallel is also an equidistantly mapped parallel, but that the reverse need not be true. If the parallel is mapped equidistantly in the direction of the parallel, then its length in the projection plane is equal to the length of that parallel on the sphere. The opposite does not have to be true, i.e., if the length of the image of the parallel in the projection plane is equal to the length of the parallel on the sphere, this does not mean that the parallel was mapped equidistantly. In addition to standard and equidistant parallels, the concept of parallels of true length also appears in the theory of map projections. They should also be distinguished from standard and equidistant parallels. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
31. Effectual topological complexity.
- Author
-
Cadavid-Aguilar, Natalia, González, Jesús, Gutiérrez, Bárbara, and Ipanaque-Zapata, Cesar A.
- Subjects
MAP projection ,TORUS ,ORBITS (Astronomy) ,SPHERES - Abstract
We introduce the effectual topological complexity (ETC) of a G -space X. This is a G -equivariant homotopy invariant sitting in between the effective topological complexity of the pair (X , G) and the (regular) topological complexity of the orbit space X / G. We study ETC for spheres and surfaces with antipodal involution, obtaining a full computation in the case of the torus. This allows us to prove the vanishing of twice the nontrivial obstruction responsible for the fact that the topological complexity of the Klein bottle is 4. In addition, this gives a counterexample to the possibility — suggested in Pavešić's work on the topological complexity of a map — that ETC of (X , G) would agree with Farber's TC (X) whenever the projection map X → X / G is finitely sheeted. We conjecture that ETC of spheres with antipodal action recasts the Hopf invariant one problem, and describe (conjecturally optimal) effectual motion planners. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
32. Development of a Monitoring and Visualization Tool for Acts of terrorism in Mindanao, Philippines.
- Author
-
Yungco, Nicky C. and Polestico, Daisy Lou L.
- Subjects
TERRORISM ,DATA visualization ,MAP projection ,PYTHON programming language ,FEATURE selection ,AUTOMOBILE dashboards ,DATABASES - Abstract
Terrorism poses a significant threat to security, and the need for an accurate monitoring visualization tool is essential for effective counterterrorism. However, the unavailability of such a customized tool is still a challenge in Mindanao, Philippines. Therefore, a terrorism visualization tool was developed in this study, covering the years 1975 to 2017. The methodology involved intensive data collection from the Global Terrorism Database and other reliable sources and featured the design development of a visualization tool in the form of a dashboard using Python. Also, regions with high terrorism activities along with major perpetrators have been presented. Findings indicate that Maguindanao yields the highest death frequency, with New People's Army (NPA) as the leading perpetrator as verified by the spatial map projection and overall preliminary prediction. In conclusion, with proper data management and feature selection, the developed tool is found to be highly viable and sufficient for decision-making. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
33. Rabies virus-based barcoded neuroanatomy resolved by single-cell RNA and in situ sequencing.
- Author
-
Aixin Zhang, Lei Jin, Shenqin Yao, Makoto Matsuyama, van Velthoven, Cindy T. J., Sullivan, Heather Anne, Na Sun, Kellis, Manolis, Tasic, Bosiljka, Wickersham, Ian, and Xiaoyin Chen
- Subjects
- *
RNA sequencing , *NEUROANATOMY , *RABIES , *RABIES virus , *MAP projection , *GENE expression - Abstract
Mapping the connectivity of diverse neuronal types provides the foundation for understanding the structure and function of neural circuits. High-throughput and low-cost neuroanatomical techniques based on RNA barcode sequencing have the potential to map circuits at cellular resolution and a brain-wide scale, but existing Sindbis virus-based techniques can only map long-range projections using anterograde tracing approaches. Rabies virus can complement anterograde tracing approaches by enabling either retrograde labeling of projection neurons or monosynaptic tracing of direct inputs to genetically targeted postsynaptic neurons. However, barcoded rabies virus has so far been only used to map non-neuronal cellular interactions in vivo and synaptic connectivity of cultured neurons. Here we combine barcoded rabies virus with single-cell and in situ sequencing to perform retrograde labeling and transsynaptic labeling in the mouse brain. We sequenced 96 retrogradely labeled cells and 295 transsynaptically labeled cells using single-cell RNA-seq, and 4130 retrogradely labeled cells and 2914 transsynaptically labeled cells in situ. We found that the transcriptomic identities of rabies virus-infected cells can be robustly identified using both single-cell RNA-seq and in situ sequencing. By associating gene expression with connectivity inferred from barcode sequencing, we distinguished long-range projecting cortical cell types from multiple cortical areas and identified cell types with converging or diverging synaptic connectivity. Combining in situ sequencing with barcoded rabies virus complements existing sequencing-based neuroanatomical techniques and provides a potential path for mapping synaptic connectivity of neuronal types at scale. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
34. Secant Cylinders Are Evil—A Case Study on the Standard Lines of the Universal Transverse Mercator and Universal Polar Stereographic Projections.
- Author
-
Kerkovits, Krisztián
- Subjects
- *
SPHERICAL projection , *MAP projection , *CONCEPT mapping , *CONFORMAL mapping , *GOOD & evil - Abstract
The literature usually calls downscaled versions of basic conformal map projections "secant", referring to conceptual developable map surfaces that intersect the reference frame. However, recent studies pointed out on the examples of various mappings of the sphere that this model may lead to incorrect conclusions. In this study, we examine the paradigm of secant surfaces for two popular map projections of the ellipsoid, the UTM (Universal Transverse Mercator) and the UPS (Universal Polar Stereographic) projections. Results will show that ellipsoidal map projections can exhibit further anomalies. To support the shift to a paradigm avoiding developable map surfaces, this study recommends the new term reduced map projection with a proper and simple definition to be used instead of secant map projections. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
35. Mapping Hyperion in Projections of the Triaxial Ellipsoid Based on a New Reference Network and a Digital Terrain Model.
- Author
-
Sokolov, A. I., Nadezhdina, I. E., Nyrtsov, M. V., Zubarev, A.E., Fleis, M. E., and Kozlova, N. A.
- Subjects
- *
DIGITAL elevation models , *MAP projection , *ELLIPSOIDS - Abstract
The work used data on Saturn's satellite Hyperion obtained from the flight results of the Cassini spacecraft due to their completeness, resolution, and image quality. They pointed out the chaotic nature of Hyperion's rotation, as a result of which there was an ambiguity in determining its coordinate system associated with the body. The dimensions of the approximating ellipsoid and the parameters of the transition from the coordinate system, initially adopted under the assumption of uniform rotation of Hyperion around Saturn, to a coordinate system whose axes coincide with the axes of the found ellipsoid were obtained. A digital model of the Hyperion surface was also created, on the basis of which geodetic heights were calculated relative to a triaxial ellipsoid with certain parameters. The method for calculating heights is based on the combined use of the equation of the normal to the surface passing through a given point and the equation of the surface itself. As a result of the research, a map of Hyperion was compiled in the projection of the triaxial ellipsoid with horizontal lines constructed on the basis of calculated geodetic heights. An original method for studying the nature of Hyperion's rotation is presented using the projection of Saturn's position onto the surface of Hyperion for all known moments in time in an object-centric coordinate system. The implementation of this technique allowed us to assume that Hyperion's own rotation axis precesses relative to the largest axis of the body in a counterclockwise direction. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
36. Sobolev Mapping of the Bergman Projections on Generalized Hartogs Triangles.
- Author
-
Liu, Hong Yan and Tu, Zhen Han
- Subjects
- *
MAP projection , *SOBOLEV spaces , *TRIANGLES - Abstract
In this paper, we investigate Sobolev mapping properties of the Bergman projection. The domain we focus on is defined by where m = (m1, ..., mN) ∈ (ℤ+)N, n = (n1, ..., nN) ∈ (ℤ+)N, N ∈ ℤ+. Sobolev irregularity of the Bergman projections on for m = (1, ..., 1). [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
37. Point Projection Mapping System for Tracking, Registering, Labeling, and Validating Optical Tissue Measurements.
- Author
-
Feenstra, Lianne, van der Stel, Stefan D., Da Silva Guimaraes, Marcos, Dashtbozorg, Behdad, and Ruers, Theo J. M.
- Subjects
MAP projection ,MACHINE learning ,OPTICAL measurements ,ONCOLOGIC surgery ,TISSUES - Abstract
The validation of newly developed optical tissue-sensing techniques for tumor detection during cancer surgery requires an accurate correlation with the histological results. Additionally, such an accurate correlation facilitates precise data labeling for developing high-performance machine learning tissue-classification models. In this paper, a newly developed Point Projection Mapping system will be introduced, which allows non-destructive tracking of the measurement locations on tissue specimens. Additionally, a framework for accurate registration, validation, and labeling with the histopathology results is proposed and validated on a case study. The proposed framework provides a more-robust and accurate method for the tracking and validation of optical tissue-sensing techniques, which saves time and resources compared to the available conventional techniques. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
38. X-ray scatter in projection radiography.
- Author
-
Ylimaula, Satu, Räsänen, Lasse, Hurskainen, Miia, Peuna, Arttu, Julkunen, Petro, Nieminen, Miika Tapio, and Hanni, Matti
- Subjects
RADIOGRAPHY ,MAP projection ,CHEST examination ,RADIATION doses ,X-rays ,ABDOMEN ,RADIOACTIVITY ,X-ray scattering - Abstract
Projection radiography is the most common radiological modality, and radiation safety of it concerns both radiation workers and the public. We measured and generated a series of scattered radiation maps for projection radiography and estimated effective doses of the supporting person during exposure. Measured adult patient protocols included chest posterior–anterior, chest lateral, pelvis anterior–posterior (AP), abdomen AP and bedside chest AP. Maps concretise spatial distribution and the scattered radiation dose rates in different imaging protocols. Highest and lowest rates were measured in abdomen AP and bedside chest AP protocols, respectively. The effective dose of supporting person in abdomen AP examination at distance of 0.5 m was 300 nSv and in bedside supine chest AP examination at distance of 0.7 m was 0.5 nSv. The estimated annual effective dose of emergency unit radiographer was 0.11 mSv. The obtained effective dose values are small compared to annual dose limits of radiation workers and the public. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
39. TRAM: A new non‐hydrostatic fully compressible numerical model suited for all kinds of regional atmospheric predictions.
- Author
-
Romero, R.
- Subjects
- *
ATMOSPHERIC boundary layer , *ATMOSPHERIC models , *NAVIER-Stokes equations , *MAP projection , *MICROPHYSICS - Abstract
A new limited‐area numerical model (TRAM, for Triangle‐based Regional Atmospheric Model) has been built using a non‐hydrostatic and fully compressible version of the Navier–Stokes equations. Advection terms are solved using a Reconstruct–Evolve–Average (REA) strategy over the computational cells. These cells consist of equilateral triangles in the horizontal. The classical z‐coordinate is used in the vertical, allowing arbitrary stretching (e.g., higher resolution in the Planetary Boundary Layer, PBL). Proper treatment of terrain slopes in the bottom boundary conditions allows for accurately representing the orographic forcing. To gain computational efficiency, time splitting is used to integrate fast and slow terms separately and acoustic modes in the vertical are solved implicitly. For real cases on the globe, the Lambert map projection is applied, and all Coriolis and curvature terms are retained. No explicit filters are needed. The first part of the manuscript describes the dynamical core of the model and provides its thorough validation using a variety of benchmark tests (mostly in two dimensions) in the context of a dry‐adiabatic atmosphere. In the second part, TRAM is reformulated for a moist atmosphere and is completed with a proper set of physical parametrizations of cloud microphysics, cumulus convection, short and long‐wave radiation, PBL processes and surface fluxes. Various examples of the great versatility offered by this full version will be presented, with special emphasis on Mediterranean case studies. In summary, TRAM performs as well as state‐of‐the‐art numerical models and is suitable for simulating circulations ranging from small‐scale thermal bubbles (≈100 m scale) to synoptic‐scale baroclinic cyclones (>1000 km size), including orographic circulations, thermally driven flows, squall lines, supercells, all kinds of precipitation systems and medicanes. Besides opening a myriad of academic and research applications, TRAM regional forecasts at different resolutions are being disseminated in the web (see https://meteo.uib.es/tram). [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
40. Projection subspace based low-rank representation for sparse hyperspectral unmixing.
- Author
-
Zhu, Zi-Yue, Huang, Ting-Zhu, and Huang, Jie
- Subjects
- *
MAP projection , *CUBES - Abstract
With a known large spectral library, sparse hyperspectral unmixing has been taken as a hotspot in academia all these years. Its fundamental task is to estimate the abundance fractions of the spectral signatures in mixed pixels. Typically, the sparse and low-rank properties of the abundance matrix have been exploited simultaneously in the literature. Many studies only consider the low-rank property of the entire abundance matrix, however, pay less attention to the property of each abundance map. In this paper, we propose a new way to describe the low-rank prior. Firstly, an abundance cube is obtained by concatenating the abundance maps along the third dimension. We construct a lower-dimensional projection subspace of the abundance cube using a projection matrix, and the low-rankness of the abundance matrix is preserved during the projection process. Secondly, we consider the low-rank property by directly analyzing the abundance maps in the projection subspace. Finally, two algorithms, namely: projection subspace low-rank structure for sparse unmixing and projection subspace low-rank structure for bilateral sparse unmixing , are proposed based on different sparse structures of the abundance matrix. Both simulated and real-data experiments demonstrate that compared with classical sparse unmixing algorithms, the proposed ones obtain better unmixing results as well as cut down on calculation time. • We propose a projection subspace low-rank structure (PSLR) based on the characteristics of hyperspectral images. • We incorporate the low-rankness of both the abundance matrix and the projected abundance maps into the PSLR structure. • We present two novel algorithms named PSLR-SpU and PSLR-BSU for different sparse structures. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
41. New Definitions of the Isometric Latitude and the Mercator Projection.
- Author
-
Lapaine, Miljenko
- Subjects
- *
MAP projection , *NAUTICAL charts , *REAL numbers , *LONGITUDE , *APPLIED mathematics - Abstract
The short communication discusses the interrelationships of loxodromes, isometric latitudes and the normal aspect of Mercator projection. It is shown that by applying the isometric latitude, a very simple equation of the loxodrome on the sphere is reached. The consequence of this is that the isometric latitude can be defined using the generalized longitude, and not only using the latitude, as was common until now. Generalized longitude is the longitude defined for every real number; modulo 2π of generalized and usual longitude are congruent. Since the image of the loxodrome in the plane of the Mercator projection is a straight line, the isometric latitude can also be defined using this projection. Finally, a new definition of the Mercator projection is given, according to which it is a normal aspect cylindrical projection in which the images of the loxodromes on the sphere are straight lines in the plane of the projection that, together with the images of the meridians in the projection, form equal angles, as do the loxodromes with the meridians on the sphere. The short communication provides additional knowledge to all those who are interested in the theory of maps in navigation and have a piece of requisite mathematical knowledge, as well as an interest in map projections. It will be useful for teachers and students studying cartography and GIS, navigation or applied mathematics. Graphic Abstract [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
42. Enhancing urban and regional development for border security in Iran: A futures study of West Azerbaijan province.
- Author
-
Hoseinpour, Mahdi, Mousavi, Mirnajaf, and Ghalehteimouri, Kamran Jafarpour
- Subjects
- *
REGIONAL development , *BORDER security , *BORDERLANDS , *HUMAN security , *SUSTAINABLE development , *REGIONAL planning , *MAP projection - Abstract
In the border regions of Iran, which include West Azerbaijan province, the interwoven dynamics between development and security present a multifaceted set of challenges. This comprehensive study delves into the intricate relationship between these two critical elements, with a focus on elucidating potential scenarios that impact on development and security alike. Employing a rigorous methodological approach, using advanced data analysis tools and incorporating insights from experts, this research identifies seven pivotal factors that play a crucial role in shaping the sustainable development and security landscape of these border regions. By using the Method for Inserting Knowledge into Decision Support Models (Méthode d'Insertion de Connaissances dans les Modèles d'Aide à la Décision) MicMac software, an in-depth analysis of both direct and indirect variables was conducted to precisely gauge their influence in border security. The outcomes of this extensive analysis provide a solid foundation for the construction of diverse scenarios, thus offering a wide spectrum of potential future trajectories for the region. The examination of these scenarios grants invaluable insights into the intricate nexus between development and security, reinforcing the essential need for a holistic and integrated approach to regional planning. This research effectively underscores the vital imperative of nurturing synergies between security and development for the sustained progress of Iran's border areas. With a focus on empirical data and informed projections, this study sheds light on the intricate dynamics at play, emphasising the pivotal role of an integrated approach to regional advancement. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
43. Bibliography.
- Author
-
Cardona, Mylynka Kilgore and Dupont, Colin
- Subjects
- *
BIBLIOGRAPHY , *HISTORY of cartography , *ETHNOLOGY , *ANTHOLOGIES , *DIGITAL mapping , *MAP projection , *HISTORY of science , *NAUTICAL charts - Abstract
This document is a bibliography that includes items published from 2019 to 2023. It covers a wide range of topics related to cartography and maps, including the visualization of urban maps, the history of cartography, the analysis of historical maps, and the exploration of different regions and cultures. The entries follow the International Standard Bibliographic Description for Monographic Publications and provide unique reference numbers for indexing purposes. Researchers interested in cartography and its applications will find valuable information in these sources. [Extracted from the article]
- Published
- 2024
- Full Text
- View/download PDF
44. Feature-exponence mapping in language contact.
- Author
-
Alexiadou, Artemis
- Subjects
LANGUAGE contact ,GRAMMATICAL gender ,MAP projection ,WORD order (Grammar) ,PHILOSOPHY of language - Abstract
This article, titled "Feature-exponence mapping in language contact," discusses the relevance of models of grammar that distinguish between underlying syntactic features and their morpho-phonological representation in analyzing bilingual and multilingual data. The paper argues that feature reassembly, a framework developed in the 90s for studying second language acquisition, is unnecessary when using these models. The article also explores the relationship between complexity and embeddedness in feature bundles and the importance of scrutinizing the feature-exponence mapping using multilingual data. It concludes by discussing the implications of different morphological theories on the relationship between exponents and features. The article provides valuable insights into the study of language contact and its effects on grammar. [Extracted from the article]
- Published
- 2024
- Full Text
- View/download PDF
45. Emily Dickinson's GPS.
- Author
-
Crowley, John W.
- Subjects
MAP projection ,DEPTH sounding ,AMERICAN English language ,WATER depth ,LONGITUDE - Abstract
This article discusses the interpretation of Emily Dickinson's poem that includes the word "Checks" in the last line. The word was later changed to "chart" in subsequent publications, but the meaning of "Checks" has remained unclear. The author suggests that the definition of "check" as "checkered cloth" or "to variegate with cross lines" may provide insight into the meaning of the word in the poem. The author also explores Dickinson's reliance on Noah Webster's dictionary and the connection between language, nature, and spirit in her work. The article concludes by discussing the concept of "belief" in Dickinson's poetry and its connection to creating fictive explanations of natural facts. [Extracted from the article]
- Published
- 2024
- Full Text
- View/download PDF
46. Standard Points and Lines in Map Projections
- Author
-
Lapaine, Miljenko
- Published
- 2024
- Full Text
- View/download PDF
47. Comment on: "A derivative-free iterative method for nonlinear monotone equations with convex constraints".
- Author
-
Abdullahi, Muhammad, Abubakar, Auwal Bala, Feng, Yuming, and Liu, Jinkui
- Subjects
- *
NONLINEAR equations , *MAP projection , *ITERATIVE methods (Mathematics) - Abstract
For solving nonlinear monotone equations with convex constraints, Liu and Feng (Numer. Algoritm. 82(1):245–262, 2019) suggested a derivative-free iterative technique. Although they assert that the direction d k satisfies inequality (2.1), however, this is not true, as the derivation of the parameter θ k given by equation (2.7) is not correct. This led to Lemma 2.2, Lemma 3.1 and Theorem 3.1 in Liu and Feng (Numer. Algoritm. 82(1):245–262, 2019) not holding. In addition, Theorem 3.1 is still invalid as the bound for ‖ F (x k + α k ′ d k) ‖ was not established by the authors, instead the authors used the bound for ‖ F (x k + α k d k) ‖ as the bound for ‖ F (x k + α k ′ d k) ‖ . In this paper, We first describe the necessary adjustments and establish the bound for ‖ F (x k + α k ′ d k) ‖ , after which the proposed approach by Liu and Feng continues to converge globally. In addition, we provide some numerical results to support the adjustments. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
48. Who is the author of the Apian map projections?
- Author
-
KERKOVITS, Krisztian
- Subjects
- *
MAP projection , *HISTORY of cartography - Abstract
This paper aims to investigate whether Apian could be the developer of his namesake map projections. Evidences suggest that these mappings should not have been named after Apian. The most likely inventor of the Apian I map projection is Amerigo Vespucci, and the Apian II projection was probably developed only 300 years later by Frangois Arago. Given that the case of Apian map projections is not a single example when the map projection is not named after its real inventor and the original authorship of more mappings might be questioned in the future, the cartographic community should revise, whether it is a good convention to name map projections after their supposed inventor. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
49. On the Definition of Standard Parallels in Map Projections.
- Author
-
Lapaine, Miljenko
- Subjects
- *
MAP projection , *MATHEMATICAL formulas , *DEFINITIONS , *PHYSICAL distribution of goods - Abstract
The article belongs to the field of theoretical research on map projections. It is observed that there is no unique and generally accepted definition of standard parallels in the cartographic literature. For some authors, a standard line is a line along which there is no distortion, and for others, it is a line along which there is no distortion of length. At the same time, it is forgotten that the length distortions at any point generally change and depend on the direction. The main goal of this article is very simple: the sentence "linear deformation is zero in all directions" is expressed using a mathematical formula. Besides that, the paper introduces equidistance in a broader sense. This is a novelty in the theory of map projections. Equidistance is defined at a point, along a line and in an area, especially in the direction of the parallels and especially in the direction of the meridian. This enables an unambiguous definition of standard parallels. Theoretical considerations are illustrated with examples of cylindrical projections. The practical value of the proposed approach is manifested in the possibility of a better understanding of the distribution of distortions in any map projection used. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
50. A semantic-based approach to digital content placement for immersive environments.
- Author
-
Liu, Jingyang, Li, Yunzhi, and Goel, Mayank
- Subjects
- *
SHARED virtual environments , *POINT cloud , *MAP projection , *NATURAL languages - Abstract
This paper presents a semantic-based interactive system that enables virtual content placement using natural language. We propose a novel computational framework composed of three components including 3D reconstruction, 3D segmentation, and 3D annotation. Based on the framework, the system can automatically construct a semantic representation of the environment from raw point cloud data. Users can then assign virtual content to a specific physical location by referring to its semantic label. Compared with traditional projection mapping which may involve tedious manual adjustments, the proposed system can facilitate intuitive and efficient manipulation of virtual content in immersive environments through speech inputs. The technical evaluation and user study results show that the system can provide users with accurate semantic information for effective virtual content placement at room scale. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
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