Relief Images Research Articles

What Geoscience Experts And Novices Look At, And What They See, When Viewing Data Visualizations

This study examines how geoscience experts and novices make meaning from an iconic type of data visualization: shaded relief images of bathymetry and topography. Participants examined, described, and interpreted a global image, two high-resolution seafloor images, and 2 high-resolution continental images, while having their gaze direction eye-tracked and their utterances and gestures videoed. In addition, experts were asked about how they would coach an undergraduate intern on how to interpret this data. Not unexpectedly, all experts were more skillful than any of the novices at describing and explaining what they were seeing. However, the novices showed a wide range of performance. Along the continuum from weakest novice to strongest expert, proficiency developed in the following order: making qualitative observations of salient features, making simple interpretations, making quantitative observations. The eye-tracking analysis examined how the experts and novices invested 20 seconds of unguided exploration, after the image came into view but before the researcher began to ask questions. On the cartographic elements of the images, experts and novices allocated their exploration time differently: experts invested proportionately more fixations on the latitude and longitude axes, while students paid more attention to the color bar. In contrast, within the parts of the image showing the actual geomorphological data, experts and novices on average allocated their attention similarly, attending preferentially to the geologically significant landforms. Combining their spoken responses with their eye-tracking behavior, we conclude that the experts and novices are looking in the same places but “seeing” different things.

A Review of Recent Results on 3D Effects

Three dimensions or three-dimensional or are expressions that characterize the space around us, as perceived by our vision, in terms of width, height and depth. The term 3D is also (and improperly) used to refer to the representation in synthetic (digital) images, the relief of stereoscopic images or other images in relief and sometimes even the simple stereophonic effect, which Can only render 2D (it is therefore only the calculation of the projected projections, the shadows, the renderings of materials). In mathematics, this notion corresponds to Euclidean geometry in space. The space is marked by three orthogonal axes, contrary to the plane composed of two dimensions. Since its origins and long before the appearance of colour, cinema has exploited stereoscopy, mainly through the processes of anaglyphs. During the 1950 s, the Hollywood studios exploited the polarized filter system and then, from the 2000 s onwards, with the adoption of digital formats, the rooms also equipped the electronic principle with alternating shutter (active glasses). Despite some anaglyphic experiments since the 1930 and 1950 s, the commercial success of television became a reality from the end of the 1990 s to a real industrial development from the year 2000. Two principles and devices for Stereoscopic effects are commercialized: Of the active type with electronic bezels or of the passive type with polarized filter goggles. More complex and costly to industrialize in particular with regard to large screens, auto stereoscopy (relief effect without bezel) was introduced with Alioscopy since the late 1990 s, on the lenticular principle. Stereoscopic videoprojection intended for the general public requires electronic active glasses or a special screen (metallised or offering some refraction of light) associated with passive glasses with polarized filters. Three-Dimensional (3D) effects close to sharp corners of a hole in a plate with finite thickness are investigated in the present contribution. The results from detailed finite element model are analyzed to investigate the stress intensity of various fracture modes caused by the presence of a finite thickness. The results expressed in terms of stressed are compared with some recent equations. The comparison between numerical and theoretical results shows a sound agreement.

The animation of the photographic: stereoscopy and cinema. The experiments of Aurélio da Paz dos Reis

Cinema was born in a visual culture where stereoscopy played a crucial role. In this paper, I will discuss how stereoscopy and cinema derived from a common programme caused by photography that brought images and life closer, boosting an unseen period of mergers and experiments in the history of the image. The project of moving images was also a stereoscopic project. To animate the images in relief was one of the main challenges of the realism desired by nineteenth-century visual culture. In particular, I will reflect on the stereoscopic photography of Aurélio da Paz dos Reis, his cinematic experiments, the major discourses that followed and the ‘archive fever’ that hit it. Furthermore, I will consider the specificities of stereoscopy as a personal, as opposed to communal, medium and technique. I also argue that if the nineteenth-century stereo visual culture has anticipated our current personal media age, the unstable presence of stereoscopy in the twentieth-century mass media culture becomes an understandable and inevitable phenomenon.

Cloud-based Lineament Extraction of Topographic Lineaments from NASA Shuttle Radar Topography Mission Data

This paper presents initial results of a JavaTM based, feature extraction tool, which represents a standard implementation of a hill-shading algorithm that transforms a 2D image to pseudo 3D image to enhance edge contrast in combination with an edge detection Canny algorithm that performs segmentation to produce multidirectional sun-shaded images and their edges. Our goal is to firstly automate this processes in JavaTM to obtain multidirectional optimization of edge discovery and secondly scale this algorithm to the complete SRTM raster collection at multiple pixel resolutions to document the distribution of Earth topographic discontinuities from continental to regional and local scales, respectively on the order of 1000s, 100s and 10s of kilometers. This tool will support the automatic extraction of lineaments of the transformed images to predict the existence of linear features that can be often found in association with ore deposits and landslides, if they represent tectonic lineaments. The collection of processed big data, represents a multi-scale data repository that may find use for these and other geological and environmental applications. We present preliminary outputs from a case study conducted in the Flin-Flon greenstone belt in Canada, which is well known for its base-metal endowment. In this study, two main shaded relief images with multidirectional illumination were created in Java each with four azimuth angles of the light sources and from which our developed tool extracts automatically multiple lineaments. The extracted lineaments represent both positive and negative elevation breaks, due to sudden slope inversions identifying dominantly crest lines and valleys. Preliminary results show good agreement with drainage networks, mapped fault lines and orientations of structures measured in the field. The main trends of the extracted lineaments of both images are NW-SE, N-S, E-W and NE-SW.

日本海及びその周辺の地形データの統合と赤色立体地図

日本海及びその周辺の地形データの統合と赤色立体地図

Evaluation of Shallow Landslides in the Northern Walgau (Austria) Using Morphometric Analysis Techniques

Landslides play a key role in landscape evolution in the Eastern Alps. These geomorphic phenomena are influenced by multiple interdependent and interacting natural and anthropogenic factors. An in-depth evaluation of the spatial distribution of existing landslides enables to gain first insights into potentially hazardous areas. Morphometric analysis techniques of mapped landslides as well as their date of occurrence allow to infer their activity and also potential impacts on affected areas. The prevalent slow moving landslides and inactive slipping areas were mapped and analysed via digital terrain models (DTM), shaded relief images of highly resolved airborne laserscanning (ALS) data and in-field observations. Orthophotos from aerial surveys and ALS data allowed a deferred-time analyses of past landslide occurrences including a record of recent slope movements. All mapped landslides were classified and analysed with geomorphometric indices. Pedological processes, the lithological setting and anthropogenic landscape transformationwere taken into account when interpreting the results. The geomorphometrical evaluation of the sliding areas determine the creation of a multitemporal landslide inventory in the Northern Walgau.

Podoba in vloga Matere Zahodnega kraljestva v grobni umetnosti dinastije Han

Pričujoči prispevek podrobneje obravnava podobo kitajske starodavne boginje Matere Zahodnega kraljestva, v kitajščini imenovane Xiwangmu 西王母. Xiwangmu je v mitološki tradiciji prikazana kot boginja, ki poseduje eliksir nesmrtnosti in prebiva v Zahodnem raju na magični gori Kunlun 崑崙. Njeno podobo je mogoče opazovati v stenskem slikarstvu, na lakiranih izdelkih, bronastih ogledalih, največkrat pa se pojavi kot reliefna podoba na kamnih ali opekah, ki so sestavljale grobne komore ali posamezne templje na površju grobne zasnove dinastije Han (206 pr. n. št.–220 n. št.). Literarna tradicija razkriva večfunkcionalno vlogo matere s številnim atributi, ki se razvija skladno s spreminjajočimi se vrednotami družbenih mitoloških konceptov. Kakšna je njena podoba in kakšno vlogo prevzema v širšem kozmološkem konceptu v grobni umetnosti dinastije Han, je osrednja problematika pričujočega prispevka.

The Advanced Hydraulic City Structure of the Royal City of Angkor Thom and Vicinity Revealed through a High-Resolution Red Relief Image Map

Numerical topographic data acquired through airborne laser scanning (LiDAR) performed at the Angkor Archaeological Park in Cambodia in April 2012 has revealed a large number of heretofore obscured water channels and ponds (Evans et al., 2013). Using this data, a high-resolution red relief image map (RRIM) was created of areas inside and outside the moated royal capital of Angkor Thom built during the latter half of the 12th century. The land around Angkor Thom is extensively covered by tropical jungle which has relatively well preserved the original urban structures and middle/post-Angkorian period modifications and renovations by escaping human-induced surface alteration except for the tourism-related infrastructure and renovations from the 20th century onward. The RRIM provided a new visualization method of localizing, minute topographical changes in regions with large undulations over a wide area. It has proved to be effective in mapping, on a single wide-area map, the numerous buried remains that exist as comparable height differences or minute undulations measuring less than 1 meter in height, and provides a unique aerial view of their widespread distribution. Based on the RRIM map, past archaeological studies were referenced to reconstruct the layout of the water channel network system. Past studies revealed that a large number of ponds had been dug inside Angkor Thom. The RRIM expanded the investigation and revealed the existence of many ponds outside the royal capital indicating that a residential community had flourished outside the moat-surrounded capital city. This paper was discussed the functional aspects of the water channel network and ponds that utilized the gentle gradient of the natural land to overcome the climatic induced environmental changes that were characterized by an extreme divide between the rainy and dry seasons.

Detecting and Characterizing Active Thrust Fault and Deep-Seated Landslides in Dense Forest Areas of Southern Taiwan Using Airborne LiDAR DEM

Steep topographic reliefs and heavy vegetation severely limit visibility when examining geological structures and surface deformations in the field or when detecting these features with traditional approaches, such as aerial photography and satellite imagery. However, a light detection and ranging (LiDAR)-derived digital elevation model (DEM), which is directly related to the bare ground surface, is successfully employed to map topographic signatures with an appropriate scale and accuracy and facilitates measurements of fine topographic features. This study demonstrates the efficient use of 1-m-resolution LiDAR for tectonic geomorphology in forested areas and to identify a fault, a deep-seated landslide, and the regional cleavage attitude in southern Taiwan. Integrated approaches that use grayscale slope images, openness with a tint color slope visualization, the three-dimensional (3D) perspective of a red relief image map, and a field investigation are employed to identify the aforementioned features. In this study, the previously inferred Meilongshan Fault is confirmed as a NE–SW-trending, eastern dipping thrust with at least a 750 m-wide deformation zone. The site where future paleoseismological studies should be performed has been identified, and someone needs to work further on this site. Signatures of deep-seated landslides, such as double ridges, trenches, main escarpments, and extension cracks, are successfully differentiated in LiDAR DEM images through the use of different visualization techniques. Systematic parallel and continuous lineaments in the images are interpreted as the regional cleavage attitude of cleavage, and a field investigation confirms this interpretation.

Reconstructing eroded paleovolcanoes on Gran Canaria, Canary Islands, using advanced geomorphometry

Original volcanic edifices of two successive stages of Gran Canaria are reconstructed using a geomorphometric analysis of existent or restored paleosurfaces. In the reconstruction, surface fitting was applied preferably to planèzes (i.e. triangular facets of original volcano flanks) and quasi-planar surfaces, QPS (those occurring on planèzes, or scattered, slightly eroded portions derived from original cone surfaces) with the help of red relief image map (RRIM) analysis. Out of the long-lasting, Mid-Miocene to Holocene subaerial evolution of the island, the Late Miocene Fataga volcano and the subsequent, Pliocene Roque Nublo volcanoes were the largest and highest. The eruptive center of Fataga, a composite edifice (12.2–8.8Ma) that may have grown up excentrically with respect to the previous Tejeda caldera, is well-defined by both two planèzes (named Veneguera–Mogán and Fataga–Tirajana) and QPS remnants. Its calculated original volume, ≤1000km3, is close to the largest stratovolcanoes on Earth. However, its ≥3300m elevation, obtained by exponential fit, may have been significantly lower due to the complex architecture of the summit region, e.g. a caldera responsible for ignimbrite eruptions. Roque Nublo, a 3.7–2.9Ma stratovolcanic cone, which was superimposed upon the Fataga rocks ≥3km west of the Fataga center, has left no considerable paleosurfaces behind due to heavy postvolcanic erosion. Yet, its remnant formations preserved in a radial pattern unambiguously define its center. Moreover, surface fitting of the outcropping rocks can be corrected taking the erosion rate for the past 3Ma into account. Such a corrected surface fit points to a regular-shaped, ≥3000m-high cone with a 25km radius and ca. 940km3 original volume, also comparable with the dimensions of the largest terrestrial stratovolcanoes.

Application of atomic force microscopy for studying intracellular signalization in neurons

The first attempt is made at applying the method of atomic force microscopy (AFM) for determining the molecular mechanisms of intracellular signalization with the participation of Na+, K+-ATPhase playing an important role of a signal transductor (amplifier). The AFM method combined with the organotypic cultivation makes it possible to obtain quantitative information on the Young moduli of living neurons and cells subjected to the action of very low concentrations of ouabain. This substance is known to trigger in this case the intracellular signalization processes by transferring a molecular signal to the genome of a cell. The cell response is manifested in a sharp intensification of protein synthesis accompanied by a rearrangement of the cytoskeleton and activation of enzyme signal pathways in a cytosol. AFM measurements of the images of the cell surface relief are performed using the PeakForce quantitative nanomechanical properties mapping PeakForce QNM mode. The Young moduli of control neurons and of sensory neurons under the action of ouabain are measured simultaneously. It is found that the activation of the signal-transducing function of Na+, K+-ATPhase triggers intracellular signal cascades, which increase the cell stiffness. The application of the AFM method in further studies of the mechanisms of intracellular molecular processes appears as promising. Its combination with inhibitory analysis will clarify the role of individual molecules (e.g., a number of ferments) in regulation of growth and development of living organisms.

Research of the relief images forming process on the imprints by means of screen Uv-varnishes

This article describes the process of relief image forming by UV-varnishes on self-adhesive labels done by means of screen printing plates with different screen mesh - 36 and 90 lines per cm. The influence of substrates’ surface energy on the process of UV-varnish transfer has been investigated. It was defined a disproportional distribution of surface energy on nonprinted self-adhesive paper and it was determined the influence of screen ruling on the varnishing relief’s height as well as the value of substrate’s surface energy and viscosity of UV- varnish

Deriving 3D displacement vectors from multi-temporal airborne laser scanning data for landslide activity analyses

Information on geometries and kinematics of landslides are necessary to establish geological slope deformation models. We present two complementary geospatial methods to analyze landslide surface changes even in areas affected by strong surface pattern changes, making use of airborne laser scanning (ALS) data. An image correlation method based on shaded relief images with a uniformly diffuse lighting and a feature tracking based on terrain breaklines are applied on a data set of eight ALS flight campaigns analyzing an active deep-seated rockslide in the Eastern Alps (Austria). Both tracking methods are described in detail, including parameter assessment. Additionally, an accuracy assessment of the input data sets has been conducted. 3D vector displacement maps derived from image correlation are well suited for the study of landslides if only slight surface pattern changes occur. The smallest detectable displacements strongly depend on the accuracy of the ALS data and for image correlation results lie within the range of 0.24 and 0.75 m for this study. Displacement vectors derived by breakline tracking only allow to detect displacements greater than 2 m. However, in comparison to image correlation, breakline tracking is not limited to areas with slight surface pattern changes and allows us to detect displacements even in areas with strong surface pattern changes. For a comprehensive interpretation of landslide activity a combination of both methods, with consideration of additional supportive data such as elevation change images and orthoimages, is recommended.

The use of microtomography in structural geology: A new methodology to analyse fault faces

This paper describes a new methodology to kinematically analyze faults in microscale dimensions (voxel size = 40 μm), using images obtained by X-ray computed microtomography (μCT). The equipment used is a GE MS8x-130 scanner. It was developed using rocks samples from Santa Catarina State, Brazil, and constructing micro Digital Elevation Models (μDEMs) for the fault surface, for analysing microscale brittle structures including striations, roughness and steps. Shaded relief images were created for the μDEMs, which enabled the generation of profiles to classify the secondary structures associated with the main fault surface. In the case of a sample with mineral growth that covers the fault surface, it is possible to detect the kinematic geometry even with the mineral cover. This technique proved to be useful for determining the sense of movement of faults, especially when it is not possible to determine striations in macro or microscopic analysis. When the sample has mineral deposit on the surface (mineral cover) this technique allows a relative chronology and geometric characterization between the faults with and without covering.

MATLAB code to estimate landslide volume from single remote sensed image using genetic algorithm and imagery similarity measurement

Information regarding the scale of a hazard is crucial for the evaluation of its associated impact. Quantitative analysis of landslide volume immediately following the event can offer better understanding and control of contributory factors and their relative importance. Such information cannot be gathered for each landslide event, owing to limitations in obtaining useable raw data and the necessary procedures of each applied technology. Empirical rules are often used to predict volume change, but the resulting accuracy is very low. Traditional methods use photogrammetry or light detection and ranging (LiDAR) to produce a post-event digital terrain model (DTM). These methods are both costly and time-intensive. This study presents a technique to estimate terrain change volumes quickly and easily, not only reducing waiting time but also offering results with less than 25% error. A genetic algorithm (GA) programmed MATLAB is used to intelligently predict the elevation change for each pixel of an image. This deviation from the pre-event DTM becomes a candidate for the post-event DTM. Thus, each changed DTM is converted into a shadow relief image and compared with a single post-event remotely sensed image for similarity ranking. The candidates ranked in the top two thirds are retained as parent chromosomes to produce offspring in the next generation according to the rules of GAs. When the highest similarity index reaches 0.75, the DTM corresponding to that hillshade image is taken as the calculated post-event DTM. As an example, a pit with known volume is removed from a flat, inclined plane to demonstrate the theoretical capability of the code. The method is able to rapidly estimate the volume of terrain change within an error of 25%, without the delays involved in obtaining stereo image pairs, or the need for ground control points (GCPs) or professional photogrammetry software.

Airborne Laser Scanning and Image Processing Techniques for Archaeological Prospection

Abstract. Aerial photography was, for decades, an invaluable tool for archaeological prospection, in spite of the limitation of this method to deforested areas. The airborne laser scanning (ALS) method can be nowadays used to map complex areas and suitable complement earlier findings. This article describes visualization and image processing methods that can be applied on digital terrain models (DTMs) to highlight objects hidden in the landscape. Thanks to the analysis of visualized DTM it is possible to understand the landscape evolution including the differentiation between natural processes and human interventions. Different visualization methods were applied on a case study area. A system of parallel tracks hidden in a forest and its surroundings – part of old route called "Devil's Furrow" near the town of Sázava was chosen. The whole area around well known part of Devil's Furrow has not been prospected systematically yet. The data from the airborne laser scanning acquired by the Czech Office for Surveying, Mapping and Cadastre was used. The average density of the point cloud was approximately 1 point/m2 The goal of the project was to visualize the utmost smallest terrain discontinuities, e.g. tracks and erosion furrows, which some were not wholly preserved. Generally we were interested in objects that are clearly not visible in DTMs displayed in the form of shaded relief. Some of the typical visualization methods were tested (shaded relief, aspect and slope image). To get better results we applied image-processing methods that were successfully used on aerial photographs or hyperspectral images in the past. The usage of different visualization techniques on one site allowed us to verify the natural character of the southern part of Devil’s Furrow and find formations up to now hidden in the forests.

Application of Inverted Slope Images for Geological Mapping – Reduction of Artifacts in Digital Elevation Models by Filtering in the Frequency Domain

Inverted slope images created from digital elevation models (DEMs) can be used to visualize differences in lithological units and provide an indication of areas of geological outcropping. Such images are useful for geological mapping, but when created from DEMs generated from remote sensing images (“image-derived DEMs”), artifacts in the DEMs are exaggerated and give rise to unclear noisy final images. Such artifacts also affect the quality of normal slope images and shaded relief images. In contrast, DEMs created from elevation data in the form of contour maps (“contour-derived DEMs”) contain far fewer artifacts, but their availability is limited. Therefore, in order to obtain clear processed DEM images that can be used for global geological mapping, it is necessary to develop a method for reducing the number of artifacts in image-derived DEMs. In the present study, the effectiveness of a fast Fourier transform (FFT) for artifact reduction in image-derived DEMs was investigated. The FFT converts spatial data into the frequency domain, and artifacts with specific frequencies are removed by low-pass filtering. An inverse FFT is then used to return to the spatial domain, thus producing a filtered DEM with a reduced number of artifacts. The effect of the filter size on the final image quality was also investigated. The image-derived DEMs used in this study were the Shuttle Radar Topography Mission (SRTM) DEM and the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global DEM (GDEM) for Cuprite, Nevada. A comparison was made between shaded relief and inverted slope images created following artifact removal from these DEMs and equivalent images produced using the contour-derived National Elevation Dataset (NED) DEMs. It was clarified that for the image-derived DEMs, that a low-pass filter with a size of 20 to 40 % significantly reduced the number of artifacts without significant loss of terrain information. For the ASTER GDEM data, artifact reduction was found to be particularly important because the artifacts obscure the original topographic information in the inverted slope images.

Lineament Extraction from Southern Chitradurga Schist Belt using Landsat TM, ASTERGDEM and Geomatics Techniques

Lineament extraction from satellite data has been the most widely used applications in geology. Recent developments in digital image processing have made the extraction of lineament in semi-automatic to fully automatic approaches possible. In this study, a fully automatic approach, consisting of a combination of edge-line detection Canny algorithm was used, a grid operator designed for the analysis of potential field data was applied to a digital elevation model for the detection of lineaments using Landsat TM and ASTERGDEM images. At different orientations, by simulating topographic illumination under varied light directions, lineaments can be enhanced and mapped. The lineaments extracted show almost a similar orientation and differences in density. Combinations of four shaded relief images within the four sun azimuth directions of light sources at 0°, 45°, 90° and 135° give N-S, NE-SW, E-W and NW-SE directional trends. The results obtained have been evaluated using both an existing lineament map of the area and a field investigation. The high degree of consistency between the suggested method and the existing tectonic map indicates that lineaments in the study area are largely topographic. Field validation confirmed these findings except in a few well defined situations.

Incremental approach to determination of image fragment displacements during vector field construction

An algorithm of constructing displacement vector fields, based on the incremental approach to estimating displacements of image fragments, is proposed. Application of this algorithm for processing model and experimental optical images is analyzed. Noise immunity of the incremental algorithm for determining displacements is compared with that of the combined algorithm developed by the authors. It is shown that the proposed incremental algorithm ensures a more noise-immune estimate of displacements in processing images of a deformation relief essentially varying in time.

６. 斜め空中写真と赤色立体地図から読み取る災害状況

Asia Air Survey took oblique aerial photographs of Izu Oshima surface failure area on 16th October 2013. These photos and Red Relief Image Map (RRIM) based on pre-disaster 5m DEM, as well as field survey, are helpful for disaster mapping.