3,543 research outputs found

    Test and evaluation of the 2.4-micron photorefractor ocular screening system

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    An improved 2.4-m photorefractor ocular screening system was tested and evaluated. The photorefractor system works on the principal of obtaining a colored photograph of both human eyes; and, by analysis of the retinal reflex images, certain ocular defects can be detected such a refractive error, strabismus, and lens obstructions. The 2.4-m photorefractory system uses a 35-mm camera with a telephoto lens and an electronic flash attachment. Retinal reflex images obtained from the new 2.4-m system are significantly improved over earlier systems in image quality. Other features were also improved, notably portability and reduction in mass. A total of 706 school age children were photorefracted, 211 learning disabled and 495 middle school students. The total students having abnormal retinal reflexes were 156 or 22 percent, and 133 or 85 percent of the abnormal had refractive error indicated. Ophthalmological examination was performed on 60 of these students and refractive error was verified in 57 or 95 percent of those examined. The new 2.4-m system has a NASA patent pending and is authorized by the FDA. It provides a reliable means of rapidly screening the eyes of children and young adults for vision problems. It is especially useful for infants and other non-communicative children who cannot be screened by the more conventional methods such as the familiar E chart

    Outcome studies in group psychotherapy

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    The treatment manual is intended to serve more than one purpose. It is designed to be a research tool, making possible the standardization and validation of a treatment method. It is also a highly condensed primer and a practicum, offering a description of psychoanalytic group therapy which will act as a handbook for the beginner and as an aide-memoirefor the more experienced therapist. Many therapists will have had some experience with individual patients but wonder how they are to convert that knowledge into the practicalities of running a group, in which seven or eight patients are seen simultaneously. For young practitioners in a National Health Service setting, this can be a daunting prospect. It is difficult to do group therapy well, yet when it is done well it provides an invaluable therapeutic medium for a collection of patients it might be neither possible nor wise nor even necessary to see in individual treatment. In other words, there are many patients for whom a group is the treatment of choice

    Aerial photography and related products| Aids in expediting the construction and development of urban land-use maps

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    Evaluation and improvement of the workflow of digital imaging of fine art reproduction in museums

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    Fine arts refer to a broad spectrum of art formats, ie~painting, calligraphy, photography, architecture, and so forth. Fine art reproductions are to create surrogates of the original artwork that are able to faithfully deliver the aesthetics and feelings of the original. Traditionally, reproductions of fine art are made in the form of catalogs, postcards or books by museums, libraries, archives, and so on (hereafter called museums for simplicity). With the widespread adoption of digital archiving in museums, more and more artwork is reproduced to be viewed on a display. For example, artwork collections are made available through museum websites and Google Art Project for art lovers to view on their own displays. In the thesis, we study the fine art reproduction of paintings in the form of soft copy viewed on displays by answering four questions: (1) what is the impact of the viewing condition and original on image quality evaluation? (2) can image quality be improved by avoiding visual editing in current workflows of fine art reproduction? (3) can lightweight spectral imaging be used for fine art reproduction? and (4) what is the performance of spectral reproductions compared with reproductions by current workflows? We started with evaluating the perceived image quality of fine art reproduction created by representative museums in the United States under controlled and uncontrolled environments with and without the presence of the original artwork. The experimental results suggest that the image quality is highly correlated with the color accuracy of the reproduction only when the original is present and the reproduction is evaluated on a characterized display. We then examined the workflows to create these reproductions, and found that current workflows rely heavily on visual editing and retouching (global and local color adjustments on the digital reproduction) to improve the color accuracy of the reproduction. Visual editing and retouching can be both time-consuming and subjective in nature (depending on experts\u27 own experience and understanding of the artwork) lowering the efficiency of artwork digitization considerably. We therefore propose to improve the workflow of fine art reproduction by (1) automating the process of visual editing and retouching in current workflows based on RGB acquisition systems and by (2) recovering the spectral reflectance of the painting with off-the-shelf equipment under commonly available lighting conditions. Finally, we studied the perceived image quality of reproductions created by current three-channel (RGB) workflows with those by spectral imaging and those based on an exemplar-based method

    Potential role of remote sensing in disaster relief management

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    Baseline or predisaster data which would be useful to decision making in the immediate postdisaster period were suggested for the six areas of public health concern along with guidelines for organizing these data. Potential sources of these data are identified. In order to fully assess the impact of a disaster on an area, information about its predisaster status must be known. Aerial photography is one way of acquiring and recording such data

    Evaluating Appearance Differences of Color 3D Printed Objects

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    Color 3D printing is a relatively young technology with several exciting applications and challenges yet to be explored. One of those challenges is the effect that three dimensional surface geometries have on appearance. The appearance of 3D objects is complex and can be affected by the interaction between several visual appearance parameters such as color, gloss and surface texture. Since traditional printing is only 2D, several of these challenges have either been solved or never needed to be addressed. Complicating matters further, different color 3D printing technologies and materials come with their own inherent material appearance properties, necessitating the study of these appearance parameters on an individual case by case basis. Neural networks are powerful tools that are finding their way into just about every field imaginable, and the world of color science is no exception. A process described by previous researchers provides a method for picking out color sensitive neurons in a given layer of a convolutional neural network (CNN). Typically, CNNs are used for image classification but can also be used for image comparison. A siamese CNN was built and shown to be a good model for appearance differences using textured color patches designed to simulate the appearance of color 3D printed objects. A direct scaling psychophysical experiment was done to create an interval scale of perceptual appearance between color 3D printed objects printed at different angles. The objects used for this experiment were printed with an HP® Jet Fusion 580 color 3D printer. The objects exhibit print angle dependent surface textures inherent to the layered printing process itself. The preliminary siamese CNN showed that perceptual differences in the prints were likely to exist and could be modeled using a neural network. However, the results of the psychophysical experiment indicated that CIELAB color differences were extremely strong predictors of observer perceptions, even with variable surface texture in uncontrolled lighting conditions

    Assessment of ERTS-1 imagery as a tool for regional geological analysis in New York State

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    The author has identified the following significant results. Linear anomalies dominate the new geological information derived from ERTS-1 imagery, total lengths now exceeding 26,500 km. Maxima on rose diagrams for ERTS-1 anomalies correspond well with those for mapped faults and topographic lineaments. Multi-scale analysis of linears shows that single topographic linears at 1:2,500,000 may become dashed linears at 1:1,000,000 aligned zones of shorter parallel, en echelon, or conjugate linears at 1:5000,000, and shorter linears lacking any conspicuous zonal alignment at 1:250,000. Field work in the Catskills suggests that the prominent new NNE lineaments may be surface manifestations of dip slip faulting in the basement, and that it may become possible to map major joint sets over extensive plateau regions directly on the imagery. Most circular features found were explained away by U-2 airfoto analysis but several remain as anomalies. Visible glacial features include individual drumlins, drumlinoids, eskers, ice-marginal drainage channels, glacial lake shorelines, sand plains, and end moraines
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