Visualization Of 3D Models Research Articles

Geophysical modeling in gold deposit through DC Resistivity and Induced Polarization methods

Ore mining fundamentally depends on the definition of its tenor and volume, something extremely complex in disseminated mineralization, as in the case of certain types of deposits of gold and sulfites. This article proposes the use of electrical tomography for definition of a geophysical signature in terms of electrical resistivity and chargeability, in an outcrop of mineralized quartz lode at the end of an inactive gold mine. One of the targets was to analyze the continuity of the mineralized body, the occurrence of new outcrops and the applicability of the method as an auxiliary tool in mineral extraction. Three parallel lines of electrical tomography in a dipole-dipole arrangement, being orthogonal to the orientation of the gold lode, were installed in an area outside the mine. The results allowed the geophysical characterization of the mineralized zone by high resistivity (above 1000Ω.m) and high chargeability (above 30mV/V). The results of the 2D inversion models were interpolated in 3D visualization models, which allowed definition of the contour surfaces for the physical parameters measured, and the morphological pattern modeling of the mineralization. The data reveal the existence of a new lode in subsurface, localized 30m to the south of the lode outcrop. The versatility of the acquisition and data processing indicate the application potential of electrical tomography as a criterion for sampling and tenor definition in ore extraction activities, since it is objective and low cost.

Web-based visualization for 3D data in archaeology: The ADS 3D viewer

The solid geometry of archaeological deposits is fundamental to the interpretation of their chronological sequence. However, such stratigraphic sequences are generally viewed as static two-dimensional diagrammatic representations which are difficult to manipulate or to relate to real layers. The ADS 3D Viewer is a web-based resource for the management and analysis of archaeological data. The viewer was developed to take advantage of recent developments in web technology, namely the adoption of WebGL (Web Graphics Library) by current web browsers. The ADS 3D Viewer combines the potential of the 3D Heritage Online Presenter (3DHOP), a software package for the web-based visualization of 3D geometries, with the infrastructure of the Archaeology Data Service (ADS) repository, in the attempt to create a platform for the visualization and analysis of 3D data archived by the ADS.Two versions of the viewer have been developed to answer the needs of different users. The first version, the Object Level 3D Viewer, was implemented to extend the browsing capability of ADS project archives by enabling the visualization of single 3D models. The second version, the Stratigraphy 3D Viewer, is an extension which allows the exploration of a specific kind of aggregated data: the multiple layers of an archaeological stratigraphic sequence. This allows those unable to participate directly in the fieldwork to access, analyse and re-interpret the archaeological context remotely. This has the potential to transform the discipline, allowing inter-disciplinary, cross-border and ‘at-distance’ collaborative workflows, and enabling easier access to and analysis of archaeological data.

Using Saliency-Weighted Disparity Statistics for Objective Visual Comfort Assessment of Stereoscopic Images

Visual comfort assessment (VCA) for stereoscopic images is a particularly significant yet challenging task in 3D quality of experience research field. Although the subjective assessment given by human observers is known as the most reliable way to evaluate the experienced visual discomfort, it is time-consuming and non-systematic. Therefore, it is of great importance to develop objective VCA approaches that can faithfully predict the degree of visual discomfort as human beings do. In this paper, a novel two-stage objective VCA framework is proposed. The main contribution of this study is that the important visual attention mechanism of human visual system is incorporated for visual comfort-aware feature extraction. Specifically, in the first stage, we first construct an adaptive 3D visual saliency detection model to derive saliency map of a stereoscopic image, and then a set of saliency-weighted disparity statistics are computed and combined to form a single feature vector to represent a stereoscopic image in terms of visual comfort. In the second stage, a high dimensional feature vector is fused into a single visual comfort score by performing random forest algorithm. Experimental results on two benchmark databases confirm the superior performance of the proposed approach.

Geophysical modeling of the manganese deposit for Induced Polarization method in Itapira (Brazil)

This paper presents the results of the investigation of a supergene manganese occurrence in the southeast of Brazil, using the Induced Polarization geophysical method. This study aims to characterize the surface and subsurface morphology of one of these occurrences, named São Roque, based on the contrast of the electrical properties of the ore and the host rocks. The ore, which is composed mainly of manganese oxides and hydroxides and subordinated graphite, occurs in the form of small discontinuous lenses hosted by quartzites and schists of the Itapira Group. The geophysical survey consisted on 10 lines of Induced Polarization Tomography using a Wenner-Schlumberger array, with an along-line electrode separation of 10 m for all lines. The IP data were modeled through commercial inversion software to generate 2D section models of chargeability. In order to create a 3D visualization model of chargeability, the 2D inversion models were then combined and interpolated in order to create a 3D visualization model. The 3D model revealed two independent ore bodies in both surface and subsurface, characterized for high chargeability (up to 20mV/V), instead of a single elongated orebody as suggested by the lateritic surface in the field. In addition, the model showed that the orebodies are elongated perpendicular to the area main structural trend and the regional alignment of the lateritic occurrences, which can bring new ideas in terms of local exploration strategies for manganese in this context.

3D visual saliency detection model with generated disparity map

Due to the remarkable distinction between human monocular vision and binocular vision, stereoscopic visual attention becomes an emerging question in the study of 3D applications. Some of existing 3D visual saliency detection models take advantage of ground-truth disparity map to compute center-surround differences of the depth features with high computational cost. In some 3D applications, the ground-truth disparity map may not be always available. In this paper, an efficient and simple 3D visual saliency detection model is proposed without using ground-truth disparity map. The proposed model is based on a band-pass filtering method which coincides with the visual perceptual process in human visual system. Firstly, the monocular luminance, color and texture features are extracted from the left view's image; the binocular depth feature is extracted from the two views' disparity map. Then, all the feature maps are filtered to generate three types of saliency maps, i.e., 2D saliency map, texture saliency map and depth saliency map. Subsequently, the three saliency maps are fused to one 3D saliency map by a linear pooling strategy. Finally, the final 3D visual saliency map is enhanced by the center-bias factor. Experimental results on a public eye tracking database show that the proposed model achieves better detection performance with low computational cost among the existing 3D visual saliency detection models.

Development of ‘3D City Models’ using IRS Satellite Data

Urban models are computer-based solutions used for testing theories about spatial location and interaction between land uses and related activities. They also provide digital environments for testing the consequences of physical planning policies on the future form of cities. Earlier, 3D city models were prepared using stereo aerial photography, topographic data and conventional surveying. The geospatial information was extracted using either visual or digital classification techniques. Presently the 3D city models is prepared with the help of ALTM data along with very high resolution imagery, which is costly and time consuming. As alternatives, Cartosat-1 stereo data of the order of 2.5 m resolution, it becomes more practical and economical to generate digital surface model (DSM) with an accuracy of 4 m. Cartosat-II data with 1 m resolution fused with LISS-IV data give high resolution images for building footprint extraction. The availability of high resolution Cartosat-I stereo satellite data assists urban planners and municipal authorities to create a model and visualize the urban space in three dimensions. 3D visualization models have a variety of applications in urban studies. The studies includes urban morphological mapping, disaster management, updation, virtual reality and generation of fly through etc. The primary interest of the planners is not limited towards the extraction of urban features from satellite data. Planners also have interest in creation of 3D models of buildings and terrain surface for detailed urban planning. Therefore, to develop 3D city models 2.5 m Cartosat-1 stereo data fused with 1 m merged product of Cartosat-II and LISS-IV to create DSM and building footprints respectively. Keeping the significance of use of stereo satellite data, an attempt has been made to generate a 3D building model for Ahmedabad and Hyderabad cities. The 3D building model generated by employing geoinformatics techniques with Level of Details (LOD-1). The primary aim of this study was to develop geoinformatics techniques for the extraction of urban features based on object oriented classification techniques with level of details 1 (LOD-1) using photogrammetric DEM. This paper discusses all these techniques and their usefulness in 3D city modeling exercises.

AN INTERACTIVE 3D ACUPRESSURE MODEL FOR SELF TREATMENT IN REDUCING PAIN

There are many pressure points on a human body. The pressure points are specific sensitive areas on the surface of the human body going into deep tissue where the pain concentrate and accumulate on. Acupressure is an alternative way to relieve pain. This method is applied by using fingers. On medication, an effort to relieve pain by taking painkillers will cause many side effects to a human body. The objectives of this paper is to show acupressure points and its set of interconnection point in an interactive 3D visual model. This model will recommend a set of self-acupressure points for a natural self-curative therapy to relieve pain. The self-acupressure visual model has been embedded in a mobile application. This interactive 3D visual model provides an alternative way to relieve pain. It is an effective aid to help a user learn and apply self-acupressure treatment.

3D WEB VISUALIZATION OF ENVIRONMENTAL INFORMATION – INTEGRATION OF HETEROGENEOUS DATA SOURCES WHEN PROVIDING NAVIGATION AND INTERACTION

Abstract. 3D information is essential for a number of applications used daily in various domains such as crisis management, energy management, urban planning, and cultural heritage, as well as pollution and noise mapping, etc. This paper is devoted to the issue of 3D modelling from the levels of buildings to cities. The theoretical sections comprise an analysis of cartographic principles for the 3D visualization of spatial data as well as a review of technologies and data formats used in the visualization of 3D models. Emphasis was placed on the verification of available web technologies; for example, X3DOM library was chosen for the implementation of a proof-of-concept web application. The created web application displays a 3D model of the city district of Nový Lískovec in Brno, the Czech Republic. The developed 3D visualization shows a terrain model, 3D buildings, noise pollution, and other related information. Attention was paid to the areas important for handling heterogeneous input data, the design of interactive functionality, and navigation assistants. The advantages, limitations, and future development of the proposed concept are discussed in the conclusions.

Visualization of surfactant solution transport in saturated soil: an experimental study to represent wastewater loss from sewers

Surfactants are the main active agents in detergents products. Our investigation dealt with the effects of surfactants as a wastewater constituent on the infiltration process of wastewater through saturated soil. In order to more closely observe the flow’s interaction, in a laboratory experiment, a 2D Plexiglas model was filled with fine-grained soil and saturated with degassed water. The particle-free artificial laboratory wastewater was created by adding a commercially available detergent to degassed tap water producing a surfactant concentration with the strength equivalent of up to about 15 times of its critical micelle concentration. The visualization of flow was improved by adding a brilliant blue dye tracer enhancing the color contrast. Photographs were taken from the 2D model using conventional imaging equipment and were processed by image analysis to distinguish the dynamic flow interface between dyed and non-dyed areas. Primarily, the images of vertical flows were analyzed after reducing the contrast range. Next, utilizing an image analysis method, 2D images were reconstructed into 3D visualization models. Three-dimensional and cross-sectional images of the fluid–fluid–soil boundary layer revealed a rapid solute transport prevailing at the dynamic interfaces. This was confirmed with image analysis showing geometric irregularities on the soil surface.

Application of 3D WebGIS and real-time technique in earthquake information publishing and visualization

In hazard management, earthquake researchers have utilized GIS to ease the process of managing disasters. Researchers use WebGIS to assess hazards and seismic risk. Although they can provide a visual analysis platform based on GIS technology, they lack a general description in the extensibility of WebGIS for processing dynamic data, especially real-time data. In this paper, we propose a novel approach for real-time 3D visual earthquake information publishing model based on WebGIS and digital globe to improve the ability of processing real-time data in systems based on WebGIS. On the basis of the model, we implement a real-time 3D earthquake information publishing system—EqMap3D. The system can not only publish real-time earthquake information but also display these data and their background geoscience information in a 3D scene. It provides a powerful tool for display, analysis, and decision-making for researchers and administrators. It also facilitates better communication between researchers engaged in geosciences and the interested public.

A depth perception and visual comfort guided computational model for stereoscopic 3D visual saliency

With the emerging development of three-dimensional (3D) related technologies, 3D visual saliency modeling is becoming particularly important and challenging. This paper presents a new depth perception and visual comfort guided saliency computational model for stereoscopic 3D images. The prominent advantage of the proposed model is that we incorporate the influence of depth perception and visual comfort on 3D visual saliency computation. The proposed saliency model is composed of three components: 2D image saliency, depth saliency and visual comfort based saliency. In the model, color saliency, texture saliency and spatial compactness are computed respectively and fused to derive 2D image saliency. Global disparity contrast is considered to compute depth saliency. Particularly, we train a visual comfort prediction function to distinguish stereoscopic image pair as high comfortable stereo viewing (HCSV) or low comfortable stereo viewing (LCSV), and devise different computational rules to generate a visual comfort based saliency map. The final 3D saliency map is obtained by using a linear combination and enhanced by a “saliency-center bias” model. Experimental results show that the proposed 3D saliency model outperforms the state-of-the-art models on predicting human eye fixations and visual comfort assessment.

3D Visualization of the Biological Structures

In this paper we aim to present a visualization of 3D model of a protein using data stored in a molecular structure file. All our examples will be realized with geometry and texturing in Maya. It will also be used a very practical application of MEL scripting to automate a modeling. It will be presented a simulations of DNA permeation through nanopores using NAMD, VMD and Maya. In this work we will briefly describe this technique and the possibilities for its use.

Segmentation-based semi-regular remeshing of 3D models using curvature-adapted subdivision surface fitting

This paper proposes a novel method of semi-regular remeshing for triangulated surfaces to achieve superior triangles lead to advanced visualization of 3D model. It is based on mesh segmentation and subdivision surface fitting which uses curvature-adapted polygon patches. Our contribution lies in building a sophisticated system with three stages, i.e., curvature-aware mesh segmentation, submesh surface fitting to generate a high-quality semi-regular mesh and finally, stitching the segments using an efficient algorithm. Our method uses centroidal Voronoi tessellation and Lloyd’s relaxation to generate curvature-adapted site centers. Geodesic distances from site centers are used for labeling segments and indexing corner vertices for each segment boundary. Using information of site centers and corner vertices, feature-adapted polygonal patches are generated for each segment. These patches are then subdivided and optimized using squared distance metric to adjust position of the subdivision sampling with segment details and prevent oversampling. At last, an efficient stitching algorithm is introduced to connect regular submeshes together and build the final semi-regular mesh. We have demonstrated the results of our semi-regular remeshing algorithm on meshes with different topology and complexity and compared them with known methods. Superior triangle quality with higher aspect ratio together with acceptable distortion error is achieved according to the experimental results.

Identification of four Aconitum species used as "Caowu" in herbal markets by 3D reconstruction and microstructural comparison.

Authentication is the first priority when evaluating the quality of Chinese herbal medicines, particularly highly toxic medicines. The most commonly used authentication methods are morphological identification and microscopic identification. Unfortunately, these methods could not effectively evaluate some herbs with complex interior structures, such as root of Aconitum species with a circular conical shape and an interior structure with successive changes. Defining the part that should be selected as the standard plays an essential role in accurate microscopic identification. In this study, we first present a visual 3D model of Aconitum carmichaeli Debx. constructed obtained from microscopic analysis of serial sections. Based on this model, we concluded that the point of largest root diameter should be used as the standard for comparison and identification. The interior structure at this point is reproducible and its shape and appearance can easily be used to distinguish among species. We also report details of the interior structures of parts not shown in the 3D model, such as stone cells and cortical thickness. To demonstrate the usefulness of the results from the 3D model, we have distinguished the microscopic structures, at their largest segments, of the other three Aconitum species used for local habitat species of Caowu. This work provides the basis for resolution of some debate regarding the microstructural differences among these species. Thus, we conclude that the 3D model composed of serial sections has enabled the selection of a standard cross-section that will enable the accurate identification of Aconitum species in Chinese medicine.

Restoring Fort Frontenac in 3D: Effective Usage of 3D Technology for Heritage Visualization

Abstract. This paper is composed of three elements: 3D modeling, web design, and heritage visualization. The aim is to use computer graphics design to inform and create an interest in historical visualization by rebuilding Fort Frontenac using 3D modeling and interactive design. The final model will be integr ated into an interactive website to learn more about the fort’s historic imp ortance. It is apparent that using computer graphics can save time and money when it comes to historical visualization. Visitors do not have to travel to the actual archaeological buildings. They can simply use the Web in their own home to learn about this information virtually. Meticulously following historical records to create a sophisticated restoration of archaeological buildings will draw viewers into visualizations, such as the historical world of Fort Frontenac. As a result, it allows the viewers to effectively understand the fort’s social sy stem, habits, and historical events.

3D Model Based on Terrestrial Laser Scanning (TLS) Case study: The Cangkuang Temple, Garut District, West Java, Indonesia

The subject of the investigation reported in this paper is the visualization of three-dimensional (3D) surface models in a 3D mapping survey using terrestrial laser scanning (TLS). The Cangkuang Temple nearby Garut City was chosen as the object. The laser technology instruments used were a Topcon GLS-1000 (Geodetic Laser Scanner) and a Topcon IS (Image Station). Twelve points at the same position in each 3D surface model were selected. The coordinate system of the IS was then transformed into the coordinate system of the GLS-1000 using a 3D similarity transformation model. The 3D distances were calculated for each model. Differences in distance were considered as errors in the x, y, and z direction. The standard deviation of the distance differences was ±0.301 m. Some of the distance differences did not fall within the range of tolerances (about 15%). The 3D surface model visualization of the Cangkuang Temple that was created from the GLS-1000 data was more precise than the one created from the IS data. In the future, such 3D surface model visualizations could be used for documentation, preservation and reconstruction of heritage buildings.

Bio mechanics of Desending and Ascending Walk

The purpose of this study is to investigate the kinetic and kinematic data while walking upstairs then compare the results with stair descent of the same step height and stair ascent of different step inclination from the published journals and analyze the influence of subject height in young individuals. The experiment is to use Qualysis Tracking Motion to capture the motion changes of lower limb joints while stair climbing which can be analyzed to develop visual 3D model. The visual 3D model can be used to analyze the gait simulation to produce data of joint angles, velocity, and moment of hip, knee, and ankle. The ground reaction forces and joint reaction force can be obtained using force plate and inverse kinematics respectively. As a result, it is found that greater hip and knee angles, hip and knee moments are found in stair ascent compared to stair descent. Greater dorsi and plantar flexion are observed in stair descent than stair ascent. The maximum value of hip, knee, and ankle joints are rising in accordance with the increases of subject heights and different inclination. The data obtained can be used for further research to develop assistive techniques for the rehabilitation of the human lower extremity.

Introduction of a standardized multimodality image protocol for navigation-guided surgery of suspected low-grade gliomas.

OBJECT Surgery of suspected low-grade gliomas (LGGs) poses a special challenge for neurosurgeons due to their diffusely infiltrative growth and histopathological heterogeneity. Consequently, neuronavigation with multimodality imaging data, such as structural and metabolic data, fiber tracking, and 3D brain visualization, has been proposed to optimize surgery. However, currently no standardized protocol has been established for multimodality imaging data in modern glioma surgery. The aim of this study was therefore to define a specific protocol for multimodality imaging and navigation for suspected LGG. METHODS Fifty-one patients who underwent surgery for a diffusely infiltrating glioma with nonsignificant contrast enhancement on MRI and available multimodality imaging data were included. In the first 40 patients with glioma, the authors retrospectively reviewed the imaging data, including structural MRI (contrast-enhanced T1-weighted, T2-weighted, and FLAIR sequences), metabolic images derived from PET, or MR spectroscopy chemical shift imaging, fiber tracking, and 3D brain surface/vessel visualization, to define standardized image settings and specific indications for each imaging modality. The feasibility and surgical relevance of this new protocol was subsequently prospectively investigated during surgery with the assistance of an advanced electromagnetic navigation system in the remaining 11 patients. Furthermore, specific surgical outcome parameters, including the extent of resection, histological analysis of the metabolic hotspot, presence of a new postoperative neurological deficit, and intraoperative accuracy of 3D brain visualization models, were assessed in each of these patients. RESULTS After reviewing these first 40 cases of glioma, the authors defined a specific protocol with standardized image settings and specific indications that allows for optimal and simultaneous visualization of structural and metabolic data, fiber tracking, and 3D brain visualization. This new protocol was feasible and was estimated to be surgically relevant during navigation-guided surgery in all 11 patients. According to the authors' predefined surgical outcome parameters, they observed a complete resection in all resectable gliomas (n = 5) by using contour visualization with T2-weighted or FLAIR images. Additionally, tumor tissue derived from the metabolic hotspot showed the presence of malignant tissue in all WHO Grade III or IV gliomas (n = 5). Moreover, no permanent postoperative neurological deficits occurred in any of these patients, and fiber tracking and/or intraoperative monitoring were applied during surgery in the vast majority of cases (n = 10). Furthermore, the authors found a significant intraoperative topographical correlation of 3D brain surface and vessel models with gyral anatomy and superficial vessels. Finally, real-time navigation with multimodality imaging data using the advanced electromagnetic navigation system was found to be useful for precise guidance to surgical targets, such as the tumor margin or the metabolic hotspot. CONCLUSIONS In this study, the authors defined a specific protocol for multimodality imaging data in suspected LGGs, and they propose the application of this new protocol for advanced navigation-guided procedures optimally in conjunction with continuous electromagnetic instrument tracking to optimize glioma surgery.

Spatial-temporal three-dimensional GIS modeling

In this paper, we present the summarized results of investigations that concern the construction of geographic information systems (GISs) for modeling purposes to enable the spatial-temporal analysis and qualitative assessment of situations. Due to the strengthening of requirements for the control of geodynamic characteristics, which is due to a marked decline in the environment and industrial safety (first and foremost, for objects of especial importance), modeling information systems are created that allow one not only to trace but also to predict the development of a situation using visual models. Global trends in the development of three-dimensional (3D) modeling of the geoinformation systems used in Earth sciences are considered. As basic technologies, we selected information technologies of network-based analytical GISs, the distributed computing technology, the technology for visual 3D modeling, and Internet technology. As an example of using the proposed modeling method, we cite the results of investigating objects of increased technogenic and ecological hazards in the Transbaikal sector of the Mongol-Okhotsk mobile belt.

Study of Virtual Scene Interaction Based on VRML and 3DS Max

3DS MAX has a capacity of producing visual 3D model, VRML is a kind of Virtual Reality Language. The combination of the two can construct virtual scene and realize interaction between user and virtual scene. This paper introduces the method of using VRML combined with 3DS MAX to achieve dynamic interactive virtual scene, Study on several interactive modes in VRML.