The purpose of this project was to develop a document imaging application. By scanning the documents into an electronic repository, medical staff will be able to more easily store and locate these records. To make the application user friendly and facilitate staff access to patient medical records, the application is wed-based and uses the Oracle Application Server to implement a multitiered model.

Dissertation (PhD)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: The purpose of this investigation was to explore the multiple variables involved in TACT® image generation in an attempt to optimize this imaging modality for the diagnostic task of primary dental caries detection. The work is divided in seven phases in which the variables are evaluated individually. Teeth from the study samples were mounted in dental stone and imaged with a solid state digital radiography sensor. As a requisite of TACT® imaging, multiple images of the teeth were acquired from different projection angles. These resulting basis images were then used to generate TACT® slices. Variables tested in the investigation included the number of iterative restorations to which the slices were submitted, the number of basis images, the angle formed between the basis images, the two- and three-dimensional distribution of the basis projections in space, and the method through which the slices were reconstructed. For all phases, observers were asked to assess the presence or absence of primary caries in the teeth imaged using the TACT® slices treated with the different variables. Finally, to determine whether the best combination of variables produced a significant improvement in diagnostic performance, a comparison with conventional digital radiography images was carried out. No statistically significant differences were found in caries detection between TACT® slices submitted to different numbers of iterative restorations, reconstructed from basis images bearing different angular disparities, spatial distributions (in both two and three dimensions), or through different reconstruction methods. A statistically significant difference was detected between TACT® slices reconstructed from different numbers of basis projections. The final comparison showed that TACT® was not statistically superior to conventional digital radiography for the task of caries detection. The results of this investigation suggest that, although TACT® has been shown to be useful in many tasks performed in dentistry, its application in caries detection is not essential inasmuch as there are modalities that are simpler, more practical, less expensive, and that submit the patient to smaller radiation doses. Keywords: TACT, tomosynthesis, image reconstruction, digital radiography, caries detection, ROC analysis, analysis of variance / AFRIKAANSE OPSOMMING: Die doel van hierdie proefskrif was om die veelvuldige veranderlikes wat betrokke is by gewysigde spleet rekenaartomografie (Tuned Aperture Computed Tomography (TACT)) te ondersoek in 'n poging om die beeldingsmodaliteit te optimaliseer in die diagnostiese opsporing van primere karies. Die proefskrif bestaan uit 'n ekstensiewe literatuur oorsig en word in 7 fases aangebied waarin die veranderlikes individueel geevalueer word. Tande is in gips ingebed en radiografiese opnames is gemaak met behulp van 'n digitale radiografiese sensor. As 'n voorvereiste vir TACT beelding is veelvuldige beelde uit verskillende projeksiehoeke van die tande gemaak. Die resulterende basisbeelde is dan gebruik om TACT snitte te produseer. Veranderlikes wat in die proefskrif getoets is, sluit die volgende in: 'n aantal herhalende herstellings waaraan die snitte blootgestel is, die aantal basisbeelde, die hoek gevorm tussen die basisbeelde, die 2 en 3 dimensionele verspeiding van die basis projeksies in die ruimte en die metodes waardeur die snitte gerekonstrueer is. In aIle fases is waarnemers gevra om die teenwoordigheid of afwesigheid van primere karies te evalueer wat met TACT afgeneem is met in ag neming van die verskillende veranderlikes. Ten slotte, om te bepaal of die beste kombinasie van veranderlikes 'n aansienlike verbetering in diagnostiese prestasies sou meebring, is 'n vergelyking met konvensionele digitale radiografiese beelding uitgevoer. Geen statistiese beduidende verskille is waargeneem in die opsporing van karies tussen TACT snitte wat blootgestel is aan verskillende aantal herhalende herstellings, rekonstruksie van basis beelding met verskillende hoek veranderinge, ruimtelike verspreiding (beide 2 en 3 dimensioneel) of deur verskillende rekonstruksie metodes nie. 'n Statistiese beduidende verskil is waargeneem tussen TACT snitte wat van 'n verskeidenheid basis projeksies gerekonstrueer is. Die finale vergelyking het aangetoon dat TACT nie statisties beter is as konvensionele radiografie in die opsporing van karies nie. Die resultate van hierdie proefskrif het getoon dat alhoewel TACT bruikbaar is in vele prosedures wat in die tandheelkunde uitgevoer word, is die toepassing daarvan in die diagnose van karies nie noodsaaklik nie, omdat daar in die tandheelkunde modaliteite beskikbaar is, wat meer eenvoudig, meer prakties en goedkoper is, met 'n laer stralingsdosis vir die pasient.

Thesis (MPhil (Afrikaans and Dutch))--University of Stellenbosch, 2009. / This study investigates the role of that which the style concept people‐orientation plays with regard to image formation and image projection in documentation, with specific reference to the Stellenbosch University’s registration forms. The goal of this study was firstly to determine how the concept people‐orientation could be operationalized within this specific case study. Regarding image formation and image projection, the researcher aimed to determine (a) what students’ current image of the University Stellenbosch is, (b) if students regard peopleorientation as an important style aspect within communication and (c) if the presence or absence of people‐orientation has an effect on the image of an institution. The Integrated Model for Image Formation and Projection (IFP‐model), whereupon this study is based, suggests that different messages in a document can have an effect on the image of an institution. These messages can however be manipulated in order to determine or adjust the image of an institution. In reference to this, this study investigated the effects of a presence or lack of people‐orientation as an aspect of style in communication. The researcher defines people‐orientation as a concept that bears reference to those aspects which directly or indirectly writes the human role player (including the writer and the reader) into the text. In other words, it refers to communication that puts the role of the person in the foreground of the communication situation. The concept of people‐orientation is however very complex in the sense that it can be created by a number of document design aspects. Thus the best way to test people‐orientation was to identify a number of operationalizeable design aspects. The researcher selected five style aspects which at core has relevance to people‐orientation. These five aspects were forms of address, reference to self, the use of passive or active voice, the use of politeness and empathy markers and the use of graphical illustration, which for the purpose of this study also classifies as a stylistic signal. Thirty‐two respondents from the Humaniora faculties were selected to participate in this study. Although the faculty of Economical and Management Sciences and the Faculty of Law traditionally fall under this division, only the Faculty of Theology, the Faculty of Arts and the Faculty of Education were used. Gender and race were incorporated as independent variables of this study. Respondents’ attitudes were tested using interviews as the primary methodology, aided by informal questionnaires as secondary methodology. Questionnaire results were however not processed by use of the traditional statistical methods, mainly because the sample of the study was too small. These results were only functional as a basis from which tendencies could be identified. Interview results had a very multi‐dimensional quality and the researcher therefore decided that it would be best to discuss these results in a thematic order rather than listing responses in tables. The results clearly demonstrate that students have a preference for forms which contain people‐orientation and that they dislike forms which lack people‐orientation. Their responses indicate that style aspects which promote people‐orientation have a relative to high probability to positively effect an institution’s image . Thus, Afrikaans‐speaking students from the Humanioria‐faculties regard people‐orientation as an important component in the management of effective communication, especially that of a positive image.

Multimedia documents are composed of multiple file format combinations, such as image and text, image and sound, or image, text and sound. The type of multimedia document determines the form of analysis for knowledge architecture design and retrieval methods. Over the last few decades, theories of text analysis have been proposed and applied effectively. In recent years, theories of image and sound analysis have been proposed to work with text retrieval systems and progressed quickly due in part to rapid progress in computer processing speed. Retrieval of multimedia documents formerly was divided into the categories of image and text, and image and sound. While standard retrieval process begins from text only, methods are developing that allow the retrieval process to be accomplished simultaneously using text and image. Although image processing for feature extraction and text processing for term extractions are well understood, there are no prior methods that can combine these two features into a single data structure. This dissertation will introduce a common representation format for multimedia documents (CRFMD) composed of both images and text. For image and text analysis, two techniques are used: the Lorenz Information Measurement and the Word Code. A new process named Jeong's Transform is demonstrated for extraction of text and image features, combining the two previous measurements to form a single data structure. Finally, this single data measurements to form a single data structure. Finally, this single data structure is analyzed by using multi-dimensional scaling. This allows multimedia objects to be represented on a two-dimensional graph as vectors. The distance between vectors represents the magnitude of the difference between multimedia documents. This study shows that image classification on a given test set is dramatically improved when text features are encoded together with image features. This effect appears to hold true even when the available text is diffused and is not uniform with the image features. This retrieval system works by representing a multimedia document as a single data structure. CRFMD is applicable to other areas of multimedia document retrieval and processing, such as medical image retrieval, World Wide Web searching, and museum collection retrieval.

Approved for public release, distribution is unlimited / The Lineate Image Near Ultraviolet Spectrometer (LINUS) is a spectral imager developed to operate in the 0.3-0.4 micron spectral region. The 2-D imager operates with a scan mirror, forming image scenes over time intervals of 10-20 minutes. Sensor calibration was conducted in the laboratory, and the system response to Sulfur Dioxide (SO2) gas was determined. The absorption profile for SO2 was measured, and curves of growth were constructed as a function of gas concentration. Test measurements were performed at the Naval Postgraduate School (NPS), from the roof of Spanagel Hall. Field observations were conducted at a coal-burning factory site at Concord, CA with the purpose of quantifying the presence of SO2. The Concord field measurement showed traces of SO2, with further analysis still required. / Civilian, DSO National Laboratories, Singapore

Digital video is being used widely in a variety of applications such as entertainment, surveillance and security. Large amount of video in surveillance and security requires systems capable to processing video to automatically detect and recognize events to alleviate the load on humans and enable preventive actions when events are detected. The main objective of this work is the analysis of computer vision techniques and algorithms used to perform automatic detection of events in video sequences. This thesis presents a surveillance system based on optical flow and background subtraction concepts to detect events based on a motion analysis, using an event probability zone definition. Advantages, limitations, capabilities and possible solution alternatives are also discussed. The result is a system capable of detecting events of objects moving in opposing direction to a predefined condition or running in the scene, with precision greater than 50% and recall greater than 80%. / by Ricardo Augusto Castellanos Jimenez. / Thesis (M.S.C.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.

Intracavitary high dose rate (HDR) brachytherapy is a form of radiation therapy generally in which a post-surgical tissue margin is treated. The dose gradient of HDR brachytherapy is very steep, and thus small displacements of the applicator, even as small as 1 mm, could potentially cause significant variations of dose which could result in undesired side effects such as overdose of a critical organ. In this retrospective dosimetric study, the variation of dose due to various small range motions of gynecological applicators is investigated. The results show that the implementation of additional immobilization and localization devices along with other safety measures needs to be further investigated. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2015 / FAU Electronic Theses and Dissertations Collection

"Patient motion, which causes artifacts in reconstructed images, can be a serious problem in Single Photon Emission Computed Tomography (SPECT) imaging. If patient motion can be detected and quantified, the reconstruction algorithm can compensate for the motion. A real-time multi-threaded Visual Tracking System (VTS) using optical cameras, which will be suitable for deployment in clinical trials, is under development. The VTS tracks patients using multiple video images and image processing techniques, calculating patient motion in three-dimensional space. This research aimed to develop and implement an algorithm for feature matching and stereo location computation using multiple cameras. Feature matching is done based on the epipolar geometry constraints for a pair of images and extended to the multiple view case with an iterative algorithm. Stereo locations of the matches are then computed using sum of squared distances from the projected 3D lines in SPECT coordinates as the error metric. This information from the VTS, when coupled with motion assessment from the emission data itself, can provide a robust compensation for patient motion as part of reconstruction."

The term“Digital X-ray Imaging" refers to a variety of technologies that electronically capture x-ray images. Once captured the images may be electronically processed, stored, displayed and communicated. Digital imaging has the potential to overcome weaknesses inherent in traditional screen-film imaging, with high detection efficiency, high dynamic range and the capability for contrast enhancement. Image processing also makes possible innovative techniques such as computer-aided diagnosis, tomosynthesis, dual-energy imaging, and digital subtraction imaging. Several different approaches to digital imaging are being studied, and in some cases, have been developed and are being marketed. Common to all these approaches are a number of technological and medical issues to be resolved. One of the technological issues is the optimal pixel size for any particular image sensor technology. In general, the spatial resolution of the digital image is limited by the pixel size. Unfortunately while reducing pixel size improves spatial resolution this comes at the expense of signal to noise ratio (SNR). In a scintillator-charge-coupled device (CCD) system, the signal can be increased by improving the efficiency of the scintillator or by reducing noise. This study used a very low noise CCD to determine if image quality, as indicated by the modulation transfer function (MTF), the noise power spectrum (NPS) and the detective quantum efficiency (DQE), could be maintained while reducing pixel size. Two scintillators, one a commonly used radiographic screen the other a thallium doped cesium iodide scintillator, were used and the results compared. The results of this study show that image quality can be maintained as pixel size is reduced and that high DQE can be attained and maintained over a wide range of spatial frequencies with a well designed scintillator.

Magnetic Resonance Imaging (MRI) is a widely used soft tissue imaging technique that has gained considerable success because of its sensitivity to several tissue parameters. However, commercially available whole-body imaging systems with large encircling radio frequency (RF) and gradient coils are less efficient when the goal is to obtain detailed, high-resolution images with high specificity and sensitivity from localized regions of the body such as the female breast. This research addresses these problems by proposing a new design in RF coil development for breast cancer screening in a conventional 1.5T MRI system. The new design provides two resonant receiving modes that operate in a quadrature configuration, and a region of interest (ROI) that closely conforms to the shape of the female breast. We adopted an optimum design strategy that combined the analytic Biot-Savart intergral equation with the Method of Moment formulation in the development of electromagnetic models and simulation tools. These models were used to analyze the magnetic field distribution and the spatial field coverage, as well as the magnetic field uniformity in the ROI. Results from our analysis were employed in the construction of a highly scalable prototype. The validation of our design strategy is confirmed by comparisons with the commercial Ansoft HFSS v8.5 finite element package.