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Öğe Cetuximab plus radiotherapy for head and neck cancer [10](2006) Cengiz M.; Yildiz F.; Genc M.[Abstract not Available]Öğe Monitoring of corrosion in fairy chimney by close range photogrammetry(International Society for Photogrammetry and Remote Sensing, 2008) Yilmaz H.M.; Yakar M.; Yildiz F.A Fairy Chimney is a conical rock formation and typically found in the Cappadocia region of Turkey. It consists of a cap of hard rock resting on a cone-shaped pinnacle of softer rock. The geology of areas where Fairy Chimneys form typically comprises a thick layer of tuff (consolidated volcanic ash), covered by a thin layer of basalt or other volcanic rocks that are more resistant to erosion than the underlying tuff. Over time, cracks in the basalt allow the much softer tuff to be eroded and washed away. Fairy Chimneys are formed where a small cap or boulder of the original basalt remains, and protects a cone of tuff beneath it from erosion. Eventually, the tuff will be undercut to the extent that the cap falls off, and the remaining cone is then quickly eroded In this study, corrosion on the surface of fairy chimney, which is located in Selime district of Aksaray in Turkey, has been examined by digital close range photogrammetry. The fairy chimney has been evaluated by photogrammetric in two period. Its three dimensional (3D) model has been obtained. Its volume has been calculated from known heights. Corrosion in Fairy Chimney has been investigated.Öğe The registration of laser scanner three-dimensional point clouds using two-dimensional images recorded with a sensor combination camera(2012) Altuntas C.; Yildiz F.The laser scanning method has been used for three-dimensional (3-D) modelling in many applications for over two decades. Laser scanners collect spatial point data from the scan area in a short time, and laser scanning data have their own local co-ordinates in each station. The other hand, 3-D modelling applications require many scans from different stations to obtain occlusion free 3-D model. In such a case, all scans must be registered into a common reference co-ordinate system. Registration of point cloud into the reference co-ordinate system is still an important research topic in photogrammetry and computer sciences fields. Many methods have been developed for registration of point clouds. Nevertheless, if there is no implicit entity on the scan area, these methods are not practicable because corresponding points can not be selected from the point clouds. In this study point clouds were registered by the image recorded by the sensor combination camera. Although many laser scanners have integrated camera, a high resolution digital camera is usually mounted to the laser scanner for efficient 3-D modelling. The image based registrations with the sensor combination of laser scanner and camera were performed by making use of a single image, relative orientation and bundle adjustment triangulation methods. The results were compared with the iterative closest point (ICP) which is the most widely used method for registration of point clouds. © 2012 Old City Publishing, Inc.Öğe The registration of point cloud data from range imaging camera(2013) Altuntas C.; Yildiz F.The measurement and 3D modelling techniques have been evolved as parallel technological improvements. Every new technique provides an opportunity for low-cost and fast measurements. The latest method for 3D measurement is the range imaging (RIM) camera. The new period in photogrammetry and 3D modelling applications has begun with the RIM cameras, and it has brought new research areas for scientists. The measurement capabilities, accuracies and application areas of RIM cameras have been increased by the time. In this study, the registration of point cloud data of RIM camera was investigated to perform 3D modelling task. © 2013 Vilnius Gediminas Technical University (VGTU) Press Technika.Öğe Registration of terrestrial laser scanner point clouds by one image(International Society for Photogrammetry and Remote Sensing, 2008) Altuntas C.; Yildiz F.Registration of point clouds in the same coordinate system is the most important step in processing of terrestrial laser scanner measurements. Used methods for registration of point clouds have required scanned overlap area betweeen point clouds or adequate points for every scan in common coordinate system. These procedures are required time and labor more than necessary. In this study, a method has been explained for registration of point clouds in the same coordinate system by one image, which covers the scan area of each point clouds. Essentially, the method is performed in two steps. The first step for the process is calculated the exterior orientation (rotation angles and translation components) of each point clouds with respect to image coordinate system, and image and each scan axes is maked parallel for the other. Translation vector is determined by difference of projection center coordinates in each scan coordinate system. Evaluate of accuracy of the method used here is done by beforhand selected control points coordinates. Seen in the procedure, the method can be used for registration of laser scanner data but accuracy of registration of the method has yet sufficiently. The accuracies of the registration can be increased with removed distortion and other errors.Öğe Surveying and documentation of detailed historical heritage by laser scanning(International Society for Photogrammetry and Remote Sensing, 2007) Altuntas C.; Yildiz F.; Karabork H.; Yakar M.; Karasaka L.In this research, surveying and documentation of historical heritage has been aimed by using laser scanning. Developing technologies has brought out in surveying and documentation of historical heritage. Laser scanning which is the last technology in survey is proper in particularly detailed small objects. Traditional survey techniques have some limitation representation detailed object particularly elements characterized by plastic forms and complex geometrical forms. Laser scanner quickly measures with desired interval of concern object in form x,y,z coordinates. With obtaining point cloud, all decorative details of objects are visualization by enough accuracy and desired form with proper software. In this paper, Sidamara's grave in Archeological Museum of Konya, which have been detailed, has been measured and modeled. The surface models generated from point clouds have been visualization in color and gray scale mode. © 2007 International Society for Photogrammetry and Remote Sensing. All rights reserved.Öğe The use of stereophotogrammetry in oral surgery: Measurement of area changes after secondary epithelization and grafting vestibuloplasties(2012) Ozturk A.; Dolanmaz D.; Celik S.; Isik K.; Karabork H.; Yildiz F.; Yakar M.Objective: Stereophotogrammetry (SPT) is a method in which three-dimensional coordinates are calculated from multiple two-dimensional projections. The purpose of this study was to compare the surface area changes between the secondary healing and grafting vestibuloplasty techniques in the mandible by using a stereophotogrammetric technique (SPT). Patients and Methods: Thirteen patients were included in this study: six patients were managed by using full-thickness skin or palatal mucosa grafts (two full-thickness palatal mucosal grafts and four full-thickness skin grafts); the remaining seven patients, who did not accept a second surgery for graft harvesting, underwent secondary epithelization vestibuloplasties. Postoperative changes of surgical areas were measured by using SPT. Statistical Analyses: The Wilcoxon (intragroup comparisons) and Mann-Whitney U (intergroup comparisons) tests were used for analysis of data. Results: In the grafting vestibuloplasty group, the surface area gain was statistically significant (P < 0.05). In the secondary epithelization vestibuloplasty group, there was no significant difference (P > 0.05), with even decrease of surface area being noted in some cases. Conclusion: SPT is a valid method for measurement of intraoral soft tissue changes.
