Airborne lidar experiments at the Savannah River Plant

The results of remote sensing experiments at the Department of Energy (DOE) Savannah River Nuclear Facility utilizing the NASA Airborne Oceanographic Lidar (AOL) are presented. The flights were conducted in support of the numerous environmental monitoring requirements associated with the operation of the facility and for the purpose of furthering research and development of airborne lidar technology. Areas of application include airborne laser topographic mapping, hydrologic studies using fluorescent tracer dye, timber volume estimation, baseline characterization of wetlands, and aquatic chlorophyll and photopigment measurements. Conclusions relative to the usability of airborne lidar technology for the DOE for each of these remote sensing applications are discussed

Computer processing of peach tree decline data

There are no author-identified significant results in this report

Ângelo de Sousa’s photographic and film collection: strategies for the preservation of colour slide-based artworks

The Portuguese artist Ângelo de Sousa (1938-2011) produced noteworthy work in photography and experimental film. However, a lack of in-depth studies focusing on the use of these media by the artist is acknowledged. Thus, his work has been studied, particularly through unpublished documentation found in the artist’s house and in public archives, bringing new insights into his production. Despite the delay in the artistic context felt in Portugal in the post-modern period, Ângelo de Sousa produce photographic and film work perfectly in line with that of other international artists. The slide-based artwork Slides de Cavalete (1978-1979), constructed with the additive synthesis of colours, stands out as an example of the inventiveness achieved by the artist with these media. The production process behind Slides de Cavalete has been studied and reproduced, allowing for a thorough understanding of the work and contributing to the definition of its significance. The photographs and films have been gathered together in his house. Since typologies, quantities and condition of the materials were unknown, a survey was carried out to enhance knowledge of the collection and to define preservation priorities. Accordingly, 35 mm chromogenic reversal films (slides), used to produce almost all his photographic colour work, was highlighted as the set in highest risk due to colour change detected in one third of these materials. Thereby, slide-based artworks by Ângelo de Sousa were studied in further detail. The display options undertaken by the artist during his lifetime have been investigated, in order to guide the decision-making process regarding the exhibition and preservation of his slide-based artworks. Slides de Cavalete was selected as a case study, and the history of its exhibition was assessed by searching for documentation and interviewing people. Thus, it is understood that the work was first presented projected on a canvas over an easel, in 1979. Since the artist’s death, the work has been presented without this setup, and recently, as a digital projection. An exhibition was conducted at FCT NOVA, to test the variability of the work displayed with a digital and a slide projector. Based on a questionnaire, a clear preference for the slide projection was acknowledged. Thus, guidelines for the exhibition of Slides de Cavalete are defined, following its first presentation. Considering that chromogenic reversal films are highly susceptible to colour change and that there is still much to know about these materials, their molecular characterization and degradation has been studied. Different pathways to characterize chromogenic dyes are suggested based on chromatographic and spectroscopic techniques. Additionally, a methodology to accurately monitor colour change in these materials has been defined, based on samples artificially aged at different temperatures (50, 60, 70 and 80˚C) and relative humidity (40% and 60%). The samples were assessed using spectrophotometry with optical fibre probes in the ultraviolet-visible range. From the spectral data, intensity maximums, CIE L*a*b* coordinates and the total colour variation (ΔE*) have been determined. Optical microscopy and digitization have also proven useful for degradation assessment on these materials

A comparative study of methods for surface area and three-dimensional shape measurement of coral skeletons

The three-dimensional morphology and surface area of organisms such as reef-building corals is central to their biology. Consequently, being able to detect and measure this aspect of corals is critical to understanding their interactions with the surrounding environment. This study explores six different methods of three-dimensional shape and surface area measurements using the range of morphology associated with the Scleractinian corals: Goniopora tenuidens, Acropora intermedia, and Porites cylindrica. Wax dipping; foil wrapping; multi-station convergent photogrammetry that used the naturally occurring optical texture for conjugate point matching; stereo photogrammetry that used projected light to provide optical texture; a handheld laser scanner that employed two cameras and a structured light source; and X-ray computer tomography (CT) scanning were applied to each coral skeleton to determine the spatial resolution of surface detection as well as the accuracy of surface area estimate of each method. Compared with X-ray CT wax dipping provided the best estimate of the surface area of coral skeletons that had external corallites, regardless of morphological complexity. Foil wrapping consistently showed a large degree of error on all coral morphologies. The photogrammetry and laser-scanning solutions were effective only on corals with simple morphologies. The two techniques that used projected lighting were both subject to skeletal light scattering, caused by both gross morphology and meso-coral architecture and which degraded signal triangulation, but otherwise provided solutions with good spatial resolution. X-ray CT scanning provided the highest resolution surface area estimates, detecting surface features smaller than 1000 mu m(2)

A computer implementation of an orthonormal expansion method for digital image noise suppression

Images are usually corrupted by noise which comes from various sources: noise in the recording media (e.g. film grain noise), and noise introduced in the transmission channel. Noise degrades the visual quality of images and obscures the detail information in the images. One of the major sources of noise for images recorded on films is film grain noise. An orthonormal expansion algorithm for digital image noise suppression is implemented. The objective is to preserve as much sharpness and produce as few artifacts in the processed image as possible. The method sections an image into non-overlapping blocks. Each block is treated as a matrix which is decomposed as a sum of outer products of its singular vectors. The coefficient of each outer product is modified by a scaling function and the matrix is reconstructed. The resulting image shows a reduction of noise. The two major problems in the method are: 1. the blocking artifacts due to the sectioned processing, and, 2. the trade-off between the suppression of noise and the loss of sharpness. By separating the image into the low frequency and the high frequency components and processing only the latter component, the method is able to reduce the blocking artifacts to an invisible level. To obtain the optimal trade-off between the suppression of noise and the loss of sharpness, systematic variations of the coefficient scaling function were used to process the image. The best choice of the scaling function is found to be [ 1 - (σi / ai ) 3 ] which is a little different from the least-square-error estimate, [ 1 - (σi / ai ) 2 ]

An integrated study of earth resources in the state of California using remote sensing techniques

There are no author-identified significant results in this report

Literature review of the remote sensing of natural resources

Abstracts of 596 documents related to remote sensors or the remote sensing of natural resources by satellite, aircraft, or ground-based stations are presented. Topics covered include general theory, geology and hydrology, agriculture and forestry, marine sciences, urban land use, and instrumentation. Recent documents not yet cited in any of the seven information sources used for the compilation are summarized. An author/key word index is provided

An integrated study of earth resources in the state of California using remote sensing techniques

The author has identified the following significant results. The effects on estimates of monthly volume runoff were determined separately for each of the following parameters: precipitation, evapotranspiration, lower zone and upper zone tension water capacity, imperviousness of the watershed, and percent of the watershed occupied by riparian vegetation, streams, and lakes. The most sensitive and critical parameters were found to be precipitation during the entire year and springtime evapotranspiration

A contribution for the preservation of cellulose esters black and white negatives

Cellulose esters film-based negatives are known for their autocatalytic and irreversible decay. Over time, the ephemeral nature of these negatives became one of the most challenging issues for manufacturers, photographers, scientists, conservators, and overall caretakers that strive to foresee the decay of those composite materials and to develop preservation solutions. The aim of this study is to introduce an analytical methodology that can inform the conservator not only about the nature of the film base but also about its condition in a non-invasive way. For this purpose, three hundred and sixty-one cellulose nitrate and cellulose acetate film-based negatives (1930s-1950s) from Portuguese institutions were selected. The selection of the cases studies relied on three main criteria: historical framework of the collection, film characteristics (type of support, format, producers/brands) and preservation condition. The selected negatives are representative of European and North American producers. The objects were studied using infrared and Raman microspectroscopies (μ-FTIR and μ-Raman), pH and hardness measurements, and Near infrared spectroscopy. μ-FTIR analysis allowed to identify three types of film supports: cellulose nitrate, cellulose acetate and cellulose acetate butyrate. Based on the μ-FTIR analysis a correlation between molecular identification of the film base and notch codes was accomplished. For the set of negatives with cellulose acetate butyrate support no significant molecular changes were obtained, indicating that this type of negatives is considerably stable. Concerning cellulose nitrate and acetate-based negatives, μ-FTIR allowed to assess very different preservation conditions, ranging from Very Good to Severely degraded. A careful observation of the results obtained for cellulose nitrate-based negatives allowed concluding that negatives with spectral changes associated with severe degradation may have different degradation pathways according to thickness. Concerning cellulose acetate-based negatives, similar results were obtained. Moreover, the FTIR results enabled to identify a degradation trend associated with a film typology characterized by ‘U’ notch code and blue and brown anti-halation dyes. Different plasticizers, namely camphor, phosphates and phthalates, were also identified by μ-FTIR and μ-Raman analysis. pH and hardness measurements supported the spectral results obtained. It was confirmed that the de-esterification and chain-scission may be detected by their decrease. To confirm the chemical behaviour of cellulose nitrate-based negatives, an artificial ageing experiment (80⁰C, 90% RH) was carried out, followed by the same analytical methodology. The results obtained for samples artificially aged support the findings obtained from the study of historical films. These findings contribute for a review of the preservation strategies currently used, establishing a novel and non-invasive methodology which could provide accurate tools for the identification of early degradation stages of negatives with cellulose nitrate and cellulose acetate supports. By examining by μ-EDXRF and SEM-EDS the image layer of a set of cellulose nitrate negatives presenting colours, it was possible to identify the chemical elements present and correlate them with possible intensification and reduction treatments used to improve image density and contribute for the knowledge of Portuguese photographers working methods

Skylab program earth resources experiment package sensor performance evaluation, volume 1, (S190A)

The results of S190A sensor performance evaluation are summarized based on data presented by all contributors to the sensor performance evaluation interim reports. Techniques used in sensor performance evaluation are discussed. Topics discussed include: performance degradation identified during the Skylab missions, S190A and EREP system anomalies that affected S190A performance, and the performance achieved, in terms of pertinent S190A parameters. Additional analyses include final performance analyses completed after submittal of the SL4 interim sensor performance evaluation reports, including completion of detailed analyses of basic performance parameters initiated during the interim report periods and consolidation analyses to reduce independent mission data (SL2, SL3, and SL4) to determine overall performance realized during all three Skylab missions