Cartographic Design and the Space–Time Cube     

Irma Kveladze  Menno-Jan Kraak  Corné P.J.M. van Elzakker 《The Cartographic journal》2019,56(1):73-90

This paper reports on the results of an empirical evaluation that aimed to define the effectiveness and efficiency of different visual variables in depicting the Space–Time Cube’s (STC) content. Existing STC applications demonstrate that the most used visual variables are size and colour hue. Less is known, however, about their usability metrics. The research sets design criteria for STC contents, such as space–time paths, based on the cartographic design theory. The visual variables colour hue, colour value, colour saturation, size and orientation have been applied in two different use case studies. Besides, to support the three-dimensional visual environment, depth cues such as shading and transparency were considered too. User tests have been executed based on real-world problems with particular attention for the visualization strategy and data complexity. The outcomes revealed the most efficient and effective visual variables to represent data of various complexities in the STC.  相似文献   

Biocrust landscape-scale spatial distribution is strongly controlled by terrain attributes: Topographic thresholds for colonization in a semiarid badland system     

Emilio Rodríguez-Caballero  José Raúl Román  Sonia Chamizo  Beatriz Roncero Ramos  Yolanda Cantón 《地球表面变化过程与地形》2019,44(14):2771-2779

Biological soil crust, or biocrust communities, are the dominating life form in many extreme habitats, such as arid and semiarid badlands, where water scarcity and highly erodible substrates limit vegetation cover. While climate, soil and biotic factors have been described as environmental filters influencing biocrust distribution in such biomes, little is known about the effect of terrain attributes on creating specific microhabitats that promote or restrict biocrust colonization. This study aimed to identify the main terrain attributes controlling biocrust distribution in the driest badland system in Europe, the Tabernas Badlands (SE Spain). To do this, we analysed the influence of different terrain attributes related to landscape stability and microclimate formation on the spatial distribution of lichen and cyanobacteria, using field measurements and topographical information from a LiDAR survey. Our results showed that the spatial distribution of cyanobacteria-dominated biocrusts, which are physiologically and morphologically adapted to extreme drought and high UVA radiation, was mostly associated with areas of high potential incoming solar radiation. The exception was bare south-aspect hillslopes with very high sediment transport potential, where bare physically crusted soils were the dominant ground cover. Lichen-dominated biocrusts, in contrast, colonized near the top of north-aspect hillslopes, characterized by low potential incoming solar radiation and potential evapotranspiration, and their cover decreased downstream, as conditions became good enough for vascular plants. © 2019 John Wiley & Sons, Ltd. © 2019 John Wiley & Sons, Ltd.  相似文献   

Granular element method for three‐dimensional discrete element calculations     

Keng‐Wit Lim  José E. Andrade 《国际地质力学数值与分析法杂志》2014,38(2):167-188

This paper endows the recently‐proposed granular element method (GEM) with the ability to perform 3D discrete element calculations. By using non‐uniform rational B‐Splines to accurately represent complex grain geometries, we proposed an alternative approach to clustering‐based and polyhedra‐based discrete element methods whereby the need for complicated and ad hoc approaches to construct 3D grain geometries is entirely bypassed. We demonstrate the ability of GEM in capturing arbitrary‐shaped 3D grains with great ease, flexibility, and without excessive geometric information. Furthermore, the applicability of GEM is enhanced by its tight integration with existing non‐uniform rational B‐Splines modeling tools and ability to provide a seamless transition from binary images of real grain shapes (e.g., from 3D X‐ray CT) to modeling and discrete mechanics computations.Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

Erratum to: Fracture-Induced Anisotropic Attenuation     

José M. Carcione  Juan E. Santos  Stefano Picotti 《Rock Mechanics and Rock Engineering》2014,47(2):835-835

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Optical archival spectra of blazar candidates of uncertain type in the 3rd Fermi Large Area Telescope Catalog     

N. Álvarez Crespo  F. Massaro  R. D’Abrusco  M. Landoni  N. Masetti  V. Chavushyan  E. Jiménez-Bailón  F. La Franca  D. Milisavljevic  A. Paggi  V. Patiño-Álvarez  F. Ricci  Howard A. Smith 《Astrophysics and Space Science》2016,361(9):316

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Isotropic and anisotropic pointing models     

András Pál  Krisztián Vida  László Mészáros  György Mező 《Experimental Astronomy》2016,41(1-2):1-15

This paper describes an alternative approach for generating pointing models for telescopes equipped with serial kinematics, esp. equatorial or alt-az mounts. Our model construction does not exploit any assumption for the underlying physical constraints of the mount, however, one can assign various effects to the respective components of the equations. In order to recover the pointing model parameters, classical linear least squares fitting procedures can be applied. This parameterization also lacks any kind of parametric singularity. We demonstrate the efficiency of this type of model on real measurements with meter-class telescopes where the results provide a root mean square accuracy of 1.5?2 arcseconds.  相似文献   

Hydrologic models coupled with 2D hydrodynamic model for high-resolution urban flood simulation     

de Arruda Gomes  Mayara Maria  de Melo Verçosa  Lívia Fragoso  Cirilo  José Almir 《Natural Hazards》2021,108(3):3121-3157

Natural Hazards - Floods are the most frequent natural disaster and pose a very challenging threat to many cities worldwide. Understanding the flood dynamic is essential for developing strategies...  相似文献   

Relationships Between Petrophysical and Mechanical Properties of Certain Calcarenites Used in Building     

Forestieri  Giulia  de Buergo  Mónica Álvarez 《Geotechnical and Geological Engineering》2021,39(7):5021-5040

Mendicino calcarenite was once widely used in traditional constructions by Italy’s foremost stonemasons’ schools. This paper provides a complete physico-mechanical characterization in order to improve understanding of strength and durability properties and so apply that knowledge to conservation and new construction. Stone samples from three lithofacies are taken from the following quarries of Cosenza province: Scannelle in Malito; Cannataro in Carolei; Albanese in San Lucido. Samples are subjected to: X-ray diffraction, mercury intrusion porosimetry, ultrasonic pulse velocity, capillary water absorption, uniaxial compressive, flexural, point load tests with respect to the X, Y, Z axes. Malito samples exhibit creamy colour, better hydric behaviour, low open porosity, reduced water absorption capability, isotropic hydric behaviour, higher fossil abundance (both in number and size) than the lithofacies taken from Carolei and San Lucido, which exhibit whitish colour, greater strength and more homogeneous texture. The greater compactness of Carolei and San Lucido samples can be ascribed to homogeneity and low porosity and their better mechanical properties to textural features. Anisotropy plays an important role. Placing stone samples along the Z axis prevents water intrusion, and improves mechanical strength. Isotropy and compact and heterogeneous fabric in stones result in higher strength and lower water absorption.

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The Effect of Key Parameters on the Strength of a Dispersive Soil Stabilized with Sustainable Binders     

Filho  Hugo Carlos Scheuermann  Martins  Carlos Guilherme  Menezes  Ricardo José Wink  Dornelles  Lucas Eduardo  Consoli  Nilo Cesar 《Geotechnical and Geological Engineering》2021,39(7):5395-5404

Geotechnical and Geological Engineering - Dispersive soils are susceptible to phenomena of internal and external erosion when in contact with relatively pure water due to its particle’s...  相似文献   

9000 years of changes in peat organic matter composition in Store Mosse (Sweden) traced using FTIR-ATR     

Antonio Martínez Cortizas  Jenny K. Sjöström  Eleonor E. Ryberg  Malin E. Kylander  Joeri Kaal  Olalla López-Costas  Noemi Álvarez Fernández  Richard Bindler 《Boreas: An International Journal of Quaternary Research》2021,50(4):1161-1178

Store Mosse (the ‘Great Bog’ in Swedish) is one of the most extensive bog complexes in southern Sweden (~77 km²), where pioneering palaeoenvironmental research has been carried out since the early 20th century. This includes, for example, vegetation changes, carbon and nitrogen dynamics, peat decomposition, atmospheric metal pollution, mineral dust deposition, dendrochronology, and tephrochronology. Even though organic matter (OM) represents the bulk of the peat mass and its compositional change has the potential to provide crucial ecological information on bog responses to environmental factors, peat OM molecular composition has not been addressed in detail. Here, a 568-cm-deep peat sequence was studied at high resolution, by attenuated reflectance Fourier-transform infrared spectroscopy (FTIR-ATR) in the mid-infrared region (4000–400 cm^–1). Principal components analysis was performed on selected absorbances and change-point modelling was applied to the records to determine the timing of changes. Four components accounted for peat composition: (i) depletion/accumulation of labile (i.e. carbohydrates) and recalcitrant (i.e. lignin and other aromatics, aliphatics, organic acids and some N compounds) compounds, due to peat decomposition; (ii) variations in N compounds and carbohydrates; (iii) residual variation of lignin and organic acids; and (iv) residual variation of aliphatic structures. Peat decomposition showed two main patterns: a long-term trend highly correlated to peat age (r = 0.87), and a short-term trend, which showed five main phases of increased decomposition (at ~8.4–8.1, ~7.0–5.6, ~3.5–3.1, ~2.7–2.1 and ~1.6–1.3 ka) – mostly corresponding to drier climate and its effect on bog hydrology. The high peat accumulation event (~5.6–3.9 ka), described in earlier studies, is characterized by the lowest degree of peat decomposition of the whole record. Given that FTIR-ATR is a quick, non-destructive, cost-effective technique, our results indicate that it can be applied in a systematic way (including multicore studies) to peat research and provide relevant information on the evolution of peatlands.  相似文献