• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 2
  • 2
  • Tagged with
  • 5
  • 5
  • 5
  • 3
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • 2
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Surveying, modelling and visualisation of geological structures in the Tunbergettunnel

Surur, Anwar January 2008 (has links)
<p>The 3-d visualisation of a section of the Tunberget tunnel and important fracture zones was accomplished by combination of the topographic surface, measurements at the surface of fracture planes together with surfaces of dolerite dykes, results from magnetic modeling of dolerite dykes and tunnel mapping data.</p><p>The topographic surface was represented as elevation contours with 1 m equidistance. The fracture and dolerite surfaces were measured geodetically in the field from a net of 20 total station locations. Each surface was measured at 3 points to determine its strike and dip. Totally 44 strike and dip estimates were obtained. The extent at depth of the dolerite dykes was also estimated based on magnetic measurements along 3 profiles. The location of the dykes was also known from geological tunnel mapping.</p><p>ArcGIS and RockWorks have been used to process the data and to generate a 3-d visualization of the geometrical relation between targeted geological structures, the dolerite dykes and the tunnel. The area is of interest to be studied in more detail as the fracture zones and the parallel dolerite dykes connect the tunnel with a large wetland complex.</p> / QC 20100707
2

Challenges in medical visualization : an interactive approach to explore the effect of 3-D technology on the visualization of pain

Spyridonis, Fotios January 2011 (has links)
Pain experienced as a result of a disabling medical condition is a frequent problem in the clinical community and can often be present in any individual with this kind of health concern. Such pain is typically characterized by severe implications reflected on both a person‘s personal life, as well as on a country‘s health and economic systems. Research on pain has revealed that patients not only experience several types of pain that could prove to be challenging to address, but also that each individual can interpret the same type, location and severity of this pain in different subjective ways, making the need for more effective pain measurement methods an imperative and troublesome effort. In retrospect, the healthcare field is currently trying to enhance the available medical methods with alternatives that would be more efficient in providing accurate pain assessment. Most efforts revolve around traditional methods of measuring pain characteristics, which typically involve the 2-Dimensional (2-D) representation of the human body, often used to collect information regarding the type and location of pain. However, these 2-D pain drawings can be limited in their ability to efficiently visualize pain characteristics for diagnosis purposes. Nonetheless, patients have been shown to prefer such drawings. This research develops an alternative interactive software solution to help in addressing the aforementioned situation, by employing the capabilities that advancements in 3-Dimension (3-D) technology offer. Subsequently, in the anticipation that limitations of current 2-D pain visualization will be solved, the developed approach facilitates the measurement of pain experiences via a 3-D visualization model of the patient. To ensure that it can effectively perform in real-world medical practice, the 3-D pain drawing is evaluated in this research through real-life case studies that are carried out in designated settings. The research findings have shown that the developed approach can potentially make significant contributions to society, science/technology and healthcare provision, with patients and clinicians suggesting that 3-D technology can be a promising means in the pursuit for more effective pain measurement solutions.
3

A GIS-based Bayesian approach for analyzing spatial-temporal patterns of traffic crashes

Li, Linhua 02 June 2009 (has links)
This thesis develops a GIS-based Bayesian approach for area-wide traffic crash analysis. Five years of crash data from Houston, Texas, are analyzed using a geographic information system (GIS), and spatial-temporal patterns of relative crash risk are identified based on a hierarchical Bayesian approach. This Bayesian approach is used to filter the uncertainty in the data and identify and rank roadway segments with potentially high relative risks for crashes. The results provide a sound basis to take preventive actions to reduce the risks in these segments. To capture the real safety indications better, this thesis differentiates the risks in different directions of the roadways, disaggregates different road types, and utilizes GIS to analyze and visualize the spatial relative crash risks in 3-D views according to different temporal scales. Results demonstrate that the approach is effective in spatially smoothing the relative crash risks, eliminating the instability of estimates while maintaining real safety trends. The posterior risk maps show high-risk roadway segments in 3-D views, which is more reader friendly than the conventional 2-D views. The results are also useful for travelers to choose relatively safer routes.
4

A GIS-based Bayesian approach for analyzing spatial-temporal patterns of traffic crashes

Li, Linhua 02 June 2009 (has links)
This thesis develops a GIS-based Bayesian approach for area-wide traffic crash analysis. Five years of crash data from Houston, Texas, are analyzed using a geographic information system (GIS), and spatial-temporal patterns of relative crash risk are identified based on a hierarchical Bayesian approach. This Bayesian approach is used to filter the uncertainty in the data and identify and rank roadway segments with potentially high relative risks for crashes. The results provide a sound basis to take preventive actions to reduce the risks in these segments. To capture the real safety indications better, this thesis differentiates the risks in different directions of the roadways, disaggregates different road types, and utilizes GIS to analyze and visualize the spatial relative crash risks in 3-D views according to different temporal scales. Results demonstrate that the approach is effective in spatially smoothing the relative crash risks, eliminating the instability of estimates while maintaining real safety trends. The posterior risk maps show high-risk roadway segments in 3-D views, which is more reader friendly than the conventional 2-D views. The results are also useful for travelers to choose relatively safer routes.
5

Surveying, modelling and visualisation of geological structures in the Tunbergettunnel

Surur, Anwar January 2008 (has links)
The 3-d visualisation of a section of the Tunberget tunnel and important fracture zones was accomplished by combination of the topographic surface, measurements at the surface of fracture planes together with surfaces of dolerite dykes, results from magnetic modeling of dolerite dykes and tunnel mapping data. The topographic surface was represented as elevation contours with 1 m equidistance. The fracture and dolerite surfaces were measured geodetically in the field from a net of 20 total station locations. Each surface was measured at 3 points to determine its strike and dip. Totally 44 strike and dip estimates were obtained. The extent at depth of the dolerite dykes was also estimated based on magnetic measurements along 3 profiles. The location of the dykes was also known from geological tunnel mapping. ArcGIS and RockWorks have been used to process the data and to generate a 3-d visualization of the geometrical relation between targeted geological structures, the dolerite dykes and the tunnel. The area is of interest to be studied in more detail as the fracture zones and the parallel dolerite dykes connect the tunnel with a large wetland complex. / QC 20100707

Page generated in 0.1007 seconds