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  • 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.
161

Using Fringe Projection technique to form a high-resolution image from multiple low-resolution image

Yao, Yu-ting 31 July 2012 (has links)
This paper presents a set of Image Registration, Image Integration, interpolation and image restoration and other technology, the number of low-resolution images synthesized high-resolution image. Relative to the existing image fusion technology, the method provided in this paper has more advantages, such as: (1) high-precision value; (2)low computation cost; (3)a compact system; (4) applicable to noise images; (5) robotic and automatic performance.
162

Data fusion of 3D profiles measured by projected fringe profilometry

Hsu, Yi-Ling 08 July 2005 (has links)
This paper presents a novel integration technique for segmented 3D profiles measured by projected fringe profilometry. Fringe patterns are projected to the inspected surface. The projected patterns fix their positions relative to the tested object during two segmented measurements. Thus, finding two matched surface points becomes a problem of searching for two identical phases in the fused data sets. This novel integration technique can match images successfully and achieve pixel-to-pixel registration easily even in the presence of geometric deformation, illumination changes, and severe occlusions. It is superior to the other methods because of its: (1) High matching accuracy; (2) Improved robustness; (3) Reduced computational time; (4) Capability of compensating distortions of the optical system at every pixel location; (5) Suitable for images rotating or scaling; and (6) Suitable for any other projected fringe measurement method. We also propose a method to design and fabricate a 2-D fringe pattern which can be applied to the integration technique for segmented 3D profiles. Campered with using 1-D fringe patterns for image registration, using a 2-D fringe pattern saves the measurement time and further proveds more tolerence to hand the shadow and noise problems. Tests of the system performance have been carried out that the accuracy of the registration scheme is 5.96% of image pixel size. Therefore, this technique can be extensively used in modern high technology industry. Especially when it requires higher resolution close-up images or overcomes the issue of not every inspected object can be fully expressed just by a single full-field measurement, it is necessary to use this integration technique.
163

A System Thinking Approach to the Study of Organizational Starting Change : A Case Study of the Taipei-Kaohsiung Household Registration Office

Li, Shyh-Jane 18 July 2001 (has links)
It will be hard to do or be easy to do when an organization starts to change. It is so called that think globally and act locally. This research is a system thinking approach of study about how an organization starts to change. It is a case study of the household-registration offices in Taipei and Kaohsiung. This case is selected with its bureaucracy in the past, but now we can see their changes. It is worthy to study more deeply. This research begins with studying the development process of the household-registration offices in Taiwan and then inquires the backgrounds and results, which could help us to understand it. This point of view focuses on the changing processes in 1990¡¦s. Household-registration offices in Taipei and Kaohsiung began their reforms from 1990 early. It is the incentive that mayors in Taipei and Kaohsiung could be elected directly by the residents in the two cities. However, computerization was the main reason that satisfied people substantially. Computerization makes the waiting time shorten. Household-registration offices could focus on many conveniences to the people further. The reform of household-registration offices in Taipei and Kaohsiung began with the simple change and it could be seen the result immediately. The reform of household-registration offices in Taipei and Kaohsiung started with some slight matters. For instance, bureau chiefs build a promotion system and a merit system, and they earned staff¡¦s support to continue making change. Improving the environment of offices could make officers happy and then change their attitudes, so it is easy to earn citizens¡¦ commendations. Merit system could promote competition among offices and make officers endeavor further. Moreover, we can say that morale, merit, and competition can make the actions of reform produce reinforce feedback loops. It should be noticed that bureau chiefs¡¦ requests and participations in reform are the key factors to start changing, and then changing will become everyone¡¦s job. The result is to earn citizens¡¦ satisfaction.
164

none

Liu, Dreaming 10 September 2001 (has links)
none
165

By system thinking to study the influence of organizational culture to organizational initiative-The case study of Taipei and Kaohsiung household registration offices

Chen, Jia-Ni 21 January 2002 (has links)
In rapidly changing environment, organizations always think hard how to arrange changes, and it makes the ¡§organizational change¡¨ becomes a hot topic. But if the changing methods can¡¦t match with the original organizational culture, organizational members¡¦ resistance makes the change initiative fails. The household registration is the sections that gets widespread approval in governmental administration renovation, although it belongs to the governmental organization that be concerned the hardest organization to change, it still produced remarkable changing achievements. This research uses household registrations as studying case and tries to use the dynamics concept of system thinking to show the structure which hide in the back of phenomenon. It means to discover how the example to initiate change along with its original culture and take organizational culture as the main shaft to analyze and discuss the change continuity. And it is using interviewing and reference analysis to understand the content of culture and using ¡§The cultural dynamics model¡¨ to understand the transformation process of inter-level in order to make the context of research more accurate. There are some conclusions in this research: (1) the structure of household registrations results in the core culture of authority, and it can¡¦t avoid using superior-authority and supervision to drive the change. But thinking of the conflict between change things and organizational culture and the flexibility of organizational function to promote suitable change initiative. (2) Organizational members¡¦ sense of honor, confidence, and sense of responsibility because of positive feedback make them change the attitude. The members become to join change activities spontaneously. Then the loading of superior lightens. (3) Although behavior and attitude may influence the core of culture, but the process of culture change is slow and difficult. After changing, the domain culture of household registrations is still authority. If the concept of authority is opposite to the change or the positive feedback diminished the result of change will be influenced. As a whole, superficial change drives the change in household registrations. But it¡¦s better to initiate deep change, vision setting, after change initiative, and the change may last a long time.
166

A parallel geometric multigrid method for finite elements on octree meshes applied to elastic image registration

Sampath, Rahul Srinivasan. January 2009 (has links)
Thesis (Ph.D)--Computing, Georgia Institute of Technology, 2009. / Committee Chair: Vuduc, Richard; Committee Member: Biros, George; Committee Member: Davatzikos, Christos; Committee Member: Tannenbaum, Allen; Committee Member: Zhou, Hao Min. Part of the SMARTech Electronic Thesis and Dissertation Collection.
167

Σταθμισμένη αντιστοίχιση εικόνων

Λαμπρινού, Νεφέλη 15 June 2015 (has links)
Το πρόβλημα της αντιστοίχισης εικόνων είναι ένα από τα σημαντικότερα στο πεδίο της υπολογιστικής όρασης, αφού η ευθυγράμμιση δύο ή περισσότερων εικόνων χρησιμοποιείται τουλάχιστον σαν στάδιο προεπεξεργασίας σε ένα μεγάλο αριθμό εφαρμογών. Στην εργασία αυτή μας απασχόλησε το πρόβλημα της στοίχισης εικόνων στις οποίες οι φωτομετρικές παραμορφώσεις είναι τοπικές και δεν μπορούν να μοντελοποιηθούν με το γενικό σφαιρικό μοντέλο της αντίθεσης και της φωτεινότητας, ή/και τμήματα των προς στοίχιση εικόνων είναι αποκλεισμένα από τη μια από αυτές. Για την αντιμετώπιση των παραπάνω προβλημάτων, η αντιστοίχηση των εικόνων προσεγγίστηκε μέσω της σταθμισμένης ελαχιστοποίησης μετρικών σφάλματος που βασίζονται στο τετραγωνικό σφάλμα. Συγκεκριμένα, εκμεταλλευόμαστε την αμεταβλητότητα της κανονικοποιημένης κλίσης μιας εικόνας σε τοπικές φωτομετρικές παραμορφώσεις και τη δυνατότητα στοίχισης κάθε ζεύγους αντίστοιχων εικονοστοιχείων των υπό στοίχιση εικόνων με την μεγιστοποίηση της μεταξύ τους συσχέτισης. Έτσι πετυχαίνουμε την αποσύνδεση του αρχικού προβλήματος σε δύο υποπροβλήματα η λύση των οποίων καταλήγει σε δύο υπερκαθορισμένα συστήματα γραμμικών εξισώσεων, καθένα εκ των οποίων έχει ως αγνώστους τις ανά κατεύθυνση παράμετρες του μετασχηματισμού που αναζητούμε για την εξάλειψη της γεωμετρικής παραμόρφωσης και ως δεξιό μέλος τις τιμές των φωτομετρικών παραμορφώσεων. Τελικά, με την επιλογή δύο κατάλληλων υποσυνόλων των προαναφερθέντων γραμμικών εξισώσεων, που εξασφαλίζουν την εφικτότητα των επιμέρους λύσεων οδηγούμαστε στον προσδιορισμό των βέλτιστων παραμέτρων. Η προτεινόμενη τεχνική δοκιμάστηκε στη βάση προσώπων Yale Β που έχει χρησιμοποιηθεί από άλλες τεχνικές αντιστοίχισης που είναι ειδικά προσαρμοσμένες για την αντιστοίχιση προσώπων. Η απόδοση της προτεινόμενης τεχνικής είναι πολύ καλή και υπερτερεί και στα ποσοστά σύγκλισης αλλά και στην ακρίβεια των λύσεων από την απόδοση των άλλων τεχνικών τόσο στη στοίχιση εικόνων που έχουν υποστεί γεωμετρικές παραμορφώσεις (από πολύ μικρές μέχρι και πολύ έντονες) όσο και σε εικόνες με διαφορετικές έντονες φωτομετρικές παραμορφώσεις. Επίσης, η προτεινόμενη τεχνική δοκιμάστηκε στις βάσεις του Affine Covariance Regions του University of Oxford στις οποίες το περιεχόμενο των εικόνων είναι γενικό και οι ειδικού σκοπού τεχνικές αποτυγχάνουν, με εξίσου πολύ καλή απόδοση. / The image registration problem is one of the most important problems in the field of computer vision, since the process of aligning two or more images is used, at least as a preprocessing step, in many applications. In this work, we employed the problem of image alignment in which the photometric deformations are local and can not be modeled with the general spherical model of contrast and brightness, and / or portions of images to align are occluded. To address these problems, the image registration was approached by minimizing the weighted error metric based on squared error. In particular, we exploit the invariance of the normalized image gradient in local photometric deformations so we can align each pair of corresponding pixels in the images by maximizing the correlation between them. Thus, we achieve to dissolve the original problem into two subproblems the solution of which leads to two over-determined systems of linear equations, each of which has the direction parameters of the transformation we seek to estimate as unknowns and as right member the values of photometric deformations. Ultimately, the choice of two suitable subsets of the above linear equations, ensuring the feasibility of individual solutions we are lead to the identification of best parameters. The proposed technique was tested in Yale B face database which has been used by other mapping techniques adapted to matching persons. The performance of the proposed technique is very good and superior at the convergence rates and the accuracy of the solutions to the performance of other techniques concerning both images that have undergone geometrical deformation (from very small to very intense) and images in different intense photometric deformations. Also, the proposed technique was tested on database of Affine Covariance Regions of the University of Oxford in which the content of the images is general and special-purpose techniques fail, with equally good performance.
168

Towards Intelligent Tumor Tracking and Setup Verification in Radiation Therapy For Lung Cancer

Xu, Qianyi January 2007 (has links)
Lung cancer is the most deadly cancer in the United States. Radiation therapy uses ionizing radiation with high energy to destroy lung tumor cells by damaging their genetic material, preventing those cells from reproducing. The most challenging aspect of modern radiation therapy for lung cancer is the motion of lung tumors caused by patient breathing during treatment. Most gating based radiotherapy derives the tumor motion from external surrogates and generates a respiratory signal to trigger the beam. We propose a method that monitors internal diaphragm motion, which can provide a respiratory signal that is more highly correlated to lung tumor motion compared to the external surrogates. We also investigate direct tracking of the tumor in fluoroscopic video imagery. We tracked fixed tumor contours in fluoroscopic videos for 5 patients. The predominant tumor displacements are well tracked based on optical flow. Some tumors or nearby anatomy features exhibit severe nonrigid deformation, especially in the supradiaphragmatic region. By combining Active Shape Models and the respiratory signal, the deformed contours are tracked within a range defined in the training period. All the tracking results are validated by a human expert and the proposed methods are promising for applications in radiotherapy. Another important aspect of lung patient treatment is patient setup verification, which is needed to reduce inter- and intra-fractions geometry uncertainties and ensure precise dose delivery. Currently, there is no universally accepted method for lung patient verification. We propose to register 4DCT and 2D x-ray images taken before treatment to derive the couch shifts necessary for precise radiotherapy. The proposed technique leads to improved patient care.
169

Augalų registracijos žemėlapis projekto Green Environment svetainei / A Map for Registration of Plants for the Green Environment Project Website

Pachomova, Rūta 29 June 2012 (has links)
Šiame darbe analizuojama interaktyvumo sąvoka, jo vieta tinklalapiuose, išsiaiškinama interaktyvumo lygmens nustatymo svarba. Darbe aprašomas teorinių žinių pritaikymas praktikoje, remiantis realiu interaktyvaus žemėlapio kūrimu. Apžvelgiamos svarbiausios iškilusios problemos, ypatingas dėmesys skiriamas žemėlapio papildymo galimybės realizavimui, bei su šiuo funkcionalumu susijusiomis problemomis. / This work analyzes the concept of interactivity, its positioning and importance of interactivity levels. This work also applies the theoretical knowledge into practice, based on a real interactive map creation. During overview of the main encountered problems, special attention is paid to the interactive map expansion possibilities and functionality associated with this problem.
170

MRI-Guided Prostate Motion Tracking using Multislice-to-Volume Registration

TADAYYON, HADI 13 July 2010 (has links)
MRI-guided prostate needle biopsy requires compensation for organ motion between target planning and needle placement. Two questions are studied and answered in this work: is rigid registration sufficient in tracking the targets with a maximum error of 3 mm (smaller than average prostate tumor size) and how many intra-operative slices are required to obtain this accuracy? We developed rigid and deformable multislice- to-volume registration algorithms for tracking the biopsy targets within the prostate. Three orthogonal plus additional transverse intra-operative slices were acquired in the approximate center of the prostate and registered with a high-resolution target planning volume. Simulated intra-operative data, phantom data, and MRI-guided robotic prostate biopsy data were used to assess tracking accuracy. Registration tests on simulated intra-operative data with 3, 4, and 5 slices were performed to evaluate the effect on registration error and time. Results: Using three orthogonal slices pro- vides sufficient accuracy. Convergence test results on phantom images demonstrated 100% success rate for initial misalignment of 5mm. Average registration errors for the patient data were 2.55mm and 2.05mm for the rigid and deformable algorithms, respectively. The algorithm was able to capture rigid biopsy target displacements of maximum 8mm and non-rigid displacements of maximum 1.5mm. Rigid tracking appears to be promising. Deformable registration does not seem warranted. / Thesis (Master, Electrical & Computer Engineering) -- Queen's University, 2010-07-13 16:41:52.223

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