1,042 research outputs found

    The use of ERTS-1 to more fully utilize and apply marine station data to the study and productivity along the eastern shelf waters of the United States

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    The author has identified the following significant results. Sea truth data were obtained during two ERTS overpasses in waters near the entrance of the Chesapeake Bay. Correlations were made between total phytoplankton and chlorophyll values in these waters to radiance detected by ERTS in an effort to map areas of similar productivity levels. Band 4 radiance had the highest correlation to all parameters with bands 5 and 6 showing decreasing correlations in each case. The radiance values were apparently influenced by one or more factors, most likely including the sediment content of the water. Data have shown that ERTS MSS is not suitable for monitoring chlorophyll in near-shore waters where sediment loads are high. It is suggested that in more seaward or pelagic locations, that ERTS MSS would be more efficient in monitoring surface chlorophyll values and establishing direct relationships to phytoplankton concentrations

    Preliminary data for the 20 May 1974, simultaneous evaluation of remote sensors experiment

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    Several remote sensors were simultaneously used to collect data over the tidal James River from Hopewell to Norfolk, Virginia. Sensors evaluated included the Multichannel-Ocean Color Sensor, multispectral scanners, and multispectral photography. Ground truth measurements and remotely sensed data are given. Preliminary analysis indicates that suspended sediment and concentrated industrial effluent are observable from all sensors

    Spectral reflectances of natural targets for use in remote sensing studies

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    A collection of spectral reflectances of 156 natural targets is presented in a uniform format. For each target both a graphical plot and a digital tabulation of reflectance is given. The data were taken from the literature and include laboratory, field, and aircraft measurements. A discussion of the different measurements of reflectance is given, along with the changes in apparent reflectance when targets are viewed through the atmosphere. The salient features of the reflectance curves of common target types are presented and discussed

    Correlation of ERTS multispectral imagery with suspended matter and chlorophyll in lower Chesapeake Bay

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    The feasibility of using multispectral satellite imagery to monitor the characteristics of estuarine waters is being investigated. Preliminary comparisons of MSS imagery with suspended matter concentrations, particle counts, chlorophyll, transmittance and bathymetry have been made. Some visual correlation of radiance with particulates and chlorophyll has been established. Effects of bathymetry are present, and their relation to transmittance and radiance is being investigated. Greatest detail in suspended matter is revealed by MSS band 5. Near-surface suspended sediment load and chlorophyll can be observed in bands 6 and 7. Images received to date have partially defined extent and location of high suspensate concentrations. Net quantity of suspended matter in the lower Bay has been decreasing since the inception of the study, and represents the diminution of turbid flood waters carried into the Bay in late September, 1972. The results so far point to the utility of MSS imagery in monitoring estuarine water character for the assessment of siltation, productivity, and water types

    Influence of Timber Harvesting Operations and Streamside Management Zone Effectiveness on Sediment Delivery to Headwater Streams in Appalachia

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    Disturbances created by timber harvesting equipment and associated haul roads and skid trails can create overland sediment flows (sediment paths), especially in steeply sloping terrain, leading to stream sedimentation. This study investigated the effect of variables associated with GPS tracked harvest equipment movement, skid trail development and retirement, topography, and streamside management zone (SMZ) width and tree retention on sediment delivery to streams. While the intensity of harvest equipment traffic was not correlated with sediment path development, the presence and location of skid trails were. All of the sediment paths were found to originate at water control structures, influenced by microtopographic features, on the skid trails directly adjacent to SMZs. Mesic slopes were associated with increased sediment path development across all SMZ configurations. Two factors, the accumulation of coarse logging debris in the SMZ and the increased distance of skid trails to streams, were both correlated with decreased sediment path development. The study provides insight into how these variables interact and can be used to develop site-specific guidelines for SMZs in steeply sloping terrain that could improve their efficiency and effectiveness

    Correlation of chlorophyll, suspended matter, and related parameters of waters in the lower Chesapeake Bay area to LANDSAT-1 imagery

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    The author has identified the following significant results. An effort to relate water parameters of the lower Chesapeake Bay area to multispectral scanner images of LANDSAT 1 has shown that some spectral bands can be correlated to water parameters, and has demonstrated the feasibility of synoptic mapping of estuaries by satellite. Bands 5 and 6 were shown to be useful for monitoring total particles. Band 5 showed high correlation with suspended sediment concentration. Attenuation coefficients monitored continuously by ship along three baselines were cross correlated with radiance values on three days. Improved correlations resulted when tidal conditions were taken into consideration. A contouring program was developed to display sediment variation in the lower Chesapeake Bay from the MSS bands

    PdZn catalysts for CO2 hydrogenation to methanol using chemical vapour impregnation (CVI)

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    The formation of PdZn bimetallic alloys on ZnO, TiO2 and Al2O3 supports was investigated, together with the effect of alloy formation on the CO2 hydrogenation reaction. The chemical vapour impregnation (CVI) method produced PdZn nanoparticles with diameters of 3–6 nm. X-ray photoelectron spectroscopy and X-ray diffraction revealed the changes in the structure of the PdZn alloy that help stabilise formate intermediates during methanol synthesis. PdZn supported on TiO2 exhibits high methanol productivity of 1730 mmol kgcat−1 h−1 that is associated with the high dispersion of the supported PdZn alloy

    Research Project as Boundary Object: negotiating the conceptual design of a tool for International Development

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    This paper reflects on the relationship between who one designs for and what one designs in the unstructured space of designing for political change; in particular, for supporting “International Development” with ICT. We look at an interdisciplinary research project with goals and funding, but no clearly defined beneficiary group at start, and how amorphousness contributed to impact. The reported project researched a bridging tool to connect producers with consumers across global contexts and show players in the supply chain and their circumstances. We explore how both the nature of the research and the tool’s function became contested as work progressed. To tell this tale, we invoke the idea of boundary objects and the value of tacking back and forth between elastic meanings of the project’s artefacts and processes. We examine the project’s role in India, Chile and other arenas to draw out ways that it functioned as a catalyst and how absence of committed design choices acted as an unexpected strength in reaching its goals

    Just how difficult can it be counting up R&D funding for emerging technologies (and is tech mining with proxy measures going to be any better?)

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    Decision makers considering policy or strategy related to the development of emerging technologies expect high quality data on the support for different technological options. A natural starting point would be R&D funding statistics. This paper explores the limitations of such aggregated data in relation to the substance and quantification of funding for emerging technologies. Using biotechnology as an illustrative case, we test the utility of a novel taxonomy to demonstrate the endemic weaknesses in the availability and quality of data from public and private sources. Using the same taxonomy, we consider the extent to which tech-mining presents an alternative, or potentially complementary, way to determine support for emerging technologies using proxy measures such as patents and scientific publications

    Challenging Social Cognition Models of Adherence:Cycles of Discourse, Historical Bodies, and Interactional Order

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    Attempts to model individual beliefs as a means of predicting how people follow clinical advice have dominated adherence research, but with limited success. In this article, we challenge assumptions underlying this individualistic philosophy and propose an alternative formulation of context and its relationship with individual actions related to illness. Borrowing from Scollon and Scollon’s three elements of social action – “historical body,” “interaction order,” and “discourses in place” – we construct an alternative set of research methods and demonstrate their application with an example of a person talking about asthma management. We argue that talk- or illness-related behavior, both viewed as forms of social action, manifest themselves as an intersection of cycles of discourse, shifting as individuals move through these cycles across time and space. We finish by discussing how these dynamics of social action can be studied and how clinicians might use this understanding when negotiating treatment with patients
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