44,863 research outputs found

    Public or private economies of knowledge: The economics of diffusion and appropriation of bioinformatics tools

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    The past three decades have witnessed a period of great turbulence in the economies of biological knowledge, during which there has been great uncertainty as to how and where boundaries could be drawn between public or private knowledge especially with regard to the explosive growth in biological databases and their related bioinformatic tools. This paper will focus on some of the key software tools developed in relation to bio-databases. It will argue that bioinformatic tools are particularly economically unstable, and that there is a continuing tension and competition between their public and private modes of production, appropriation, distribution, and use. The paper adopts an ?instituted economic process? approach, and in this paper will elaborate on processes of making knowledge public in the creation of ?public goods?. The question is one of continuously creating and sustaining new institutions of the commons. We believe this critical to an understanding of the division and interdependency between public and private economies of knowledge

    Halogen Occultation Experiment (HALOE) optical filter characterization

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    The Halogen Occultation Experiment (HALOE) is a solar occultation experiment that will fly on the Upper Atmosphere Research Satellite to measure mixing ratio profiles of O3, H2O, NO2, NO, CH4, HCl, and HF. The inversion of the HALOE data will be critically dependent on a detailed knowledge of eight optical filters. A filter characterization program was undertaken to measure in-band transmissions, out-of-band transmissions, in-band transmission shifts with temperature, reflectivities, and age stability. Fourier Transform Infrared Spectrometers were used to perform measurements over the spectral interval 400/cm to 6300/cm (25 micrometers to 1.6 micrometers). Very high precision (0.1 percent T) in-band measurements and very high resolution (0.0001 percent T) out-of-band measurements have been made. The measurements revealed several conventional leaks at 0.01 percent transmission and greatly enhanced (1,000) leaks to the 2-element filters when placed in a Fabry-Perot cavity. Filter throughput changes by 5 percent for a 25 C change in filter temperature

    NASA-LRC faint meteor spectra

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    A brief description is given of the instrumentation, the facilities, and the patrol technique used by the NASA faint meteor spectra patrol. A classification of 500 meteor spectra obtained in the first 2-1/2 years of the patrol is reported. The general characteristics of typical spectra are discussed and preliminary conclusions drawn. Examples of unusual spectra are briefly described
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