1,016 research outputs found

    Spaceborne sensors (1983-2000 AD): A forecast of technology

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    A technical review and forecast of space technology as it applies to spaceborne sensors for future NASA missions is presented. A format for categorization of sensor systems covering the entire electromagnetic spectrum, including particles and fields is developed. Major generic sensor systems are related to their subsystems, components, and to basic research and development. General supporting technologies such as cryogenics, optical design, and data processing electronics are addressed where appropriate. The dependence of many classes of instruments on common components, basic R&D and support technologies is also illustrated. A forecast of important system designs and instrument and component performance parameters is provided for the 1983-2000 AD time frame. Some insight into the scientific and applications capabilities and goals of the sensor systems is also given

    Remote sensing by infrared heterodyne spectroscopy

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    The use of infrared heterodyne spectrocopy for the study of planetary atmospheres is discussed. Infrared heterodyne spectroscopy provides a convenient and sensitive method for measuring the true intensity profiles of atmospheric spectral lines. Application of radiative transfer theory to measured lineshapes can then permit the study of molecular abundances, temperatures, total pressures, excitation conditions, and dynamics of the regions of line formation. The theory of formation of atmospheric spectral lines and the retrieval of the information contained in these molecular lines is illustrated. Notable successes of such retrievals from infrared heterodyne measurements on Venus, Mars, Jupiter and the Earth are given. A discussion of developments in infrared heterodyne technology is also presented

    Advanced infrared astronomy

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    This task supports the application of infrared heterodyne and Fourier transform spectroscopy to ultra-high resolution studies of molecular constituents of planetary astomspheres and cometary comae. High spectral and spatial resolutions are especially useful for detection and study of localized, non-thermal phenomena in low temperature and low density regions, for detection of trace constituents and for measurement of winds and dynamical phenomena such as thermal tides. Measurement and analysis of individual spectial lines permits retrieval of atmospheric molecular abundances and temperatures and thus, information on local photochemical processes. Determination of absolute line positions to better than 10 to the minus eighth power permits direct measurements of gas velocity to a few meters/sec. Observations are made from ground based heterodyne spectrometers at the Kitt Peak McMath solar telescope and from the NASA infrared Telescope Facility on Mauna Kea, Hawaii. Wind velocities at 110km altitude on Venus were extracted approximately 1 m/sec from measurements of non-thermal emission cores of 10.3 micron CO2 lines. Results indicate a subsolar to antisolar circulationwith a small zonal retrograde component

    Optical considerations in infrared heterodyne spectrometer design

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    The optical design considerations for optimization of sensitivity, tunability, and versatility of an infrared heterodyne spectrometer are discussed using the GSFC CO2 laser heterodyne spectrometer optical front end as an example. Problems related to the coherent nature of the laser local oscillator beam (e.g., interference effects at edges of optical elements and at the beam combining beamsplitter) are described and proper beamsplitter design discussed. Optimum matching to the telescope is discussed. The severe effects of large central obscuration on the coherent telescope efficiency are described and steps to partially recover the lost system sensitivity are proposed. Measurements made with the GSFC 48 inch telescope (linear obscuration rate = 0.5) and the KPNO McMathe telescope (no obscuration) are given as examples

    Infrared upconversion for astronomical applications

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    The performance of an upconversion system is examined for observation of astronomical sources in the low to middle infrared spectral range. Theoretical values for the performance parameters of an upconversion system for astronomical observations are evaluated in view of the conversion efficiencies, spectral resolution, field of view, minimum detectable source brightness and source flux. Experimental results of blackbody measurements and molecular absorption spectrum measurements using a lithium niobate upconverter with an argon-ion laser as the pump are presented. Estimates of the expected optimum sensitivity of an upconversion device which may be built with the presently available components are given

    АКСІОСФЕРА ДУХОВНОЇ ІДЕНТИФІКАЦІЇ ОСОБИСТОСТІ (Axiosphere of Spiritual Identification of Personality)

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    Стаття присвячується осмисленню аксіосфери духовної ідентифікації особистості, особливостей функціонування та ролі цінностей та ціннісних орієнтацій людини у творенні її духовного простору. У ній фокусується увага на сутності духовної сфери, її рівнів та проявів у житті особистості, розкриваються її характерні риси функціонування через спектр аксіологічної проблематики. Розглядається питання осягнення духовного початку в історії філософської думки (The article is devoted to understanding the axiosphere of spiritual identification of personality, the functioning and role of values and value orientations in the creation of human spiritual space. It focuses attention on the nature of the spiritual area, its levels and manifestations in the life of the individual, reveals its characteristics of functioning across the spectrum axiological problems. Analyze the question of understanding the spiritual principle in the history of philosophical thought

    Sensitivity limits of an infrared heterodyne spectrometer for astrophysical applications

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    A discussion and an evaluation of the degradation in sensitivity is given for a heterodyne spectrometer employing a HgCdTe photodiode mixer and tunable diode lasers. The minimum detectable source brightness is considered as a function of the mixer parameters, transmission coefficient of the beam splitter, and local oscillator emission powers. The degradation in the minimum detectable line source brightness which results from the bandwidth being a function of the line width is evaluated and plotted as a function of the wavelength and bandwidth for various temperature to mass ratios. It is shown that the minimum achievable degradation in the sensitivity of a practical astronomical heterodyne spectrometer is approximately 30. Estimates of signal-to-noise ratios with which infrared line emission from astronomical sources of interest may be detected are given

    Understanding of Emotions and Emotion Regulation in Adolescent Females with Conduct Problems: A Qualitative Analysis

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    Adolescent girls with conduct problems were interviewed regarding their (a) understanding of positive and negative emotions, (b) parental context of experiencing emotions, (c) ways of regulating emotions, (d) success in emotion regulation, and (e) use of alternative strategies in dealing with emotions. It was found that the girls have relatively little understanding of their negative internal states and/or are unable to express them to others, especially to fathers. They have few successful strategies for regulating negative emotions in themselves and others and are unaware of alternative strategies. This dysregulatory pattern likely prevents them from learning more appropriate ways of expressing and constructively handling their negative emotions that are necessary for healthy adjustment

    Observations of the 10 micrometer natural laser emission from the mesospheres of Mars and Venus

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    Observations of the total flux and center to limb dependence of the nonthermal emission occurring in the cores of the 9.4 and 10.4 micrometers CO2 bands on Mars are compared to a theoretical model based on this mechanism. The model successfully reproduces the observed center to limb dependence of this emission, to within the limits imposed by the spatial resolution of the observations of Mars and Venus. The observed flux from Mars agrees closely with the prediction of the model; the flux observed from Venus is 74% of the flux predicted by the model. This emission is used to obtain the kinetic temperatures of the Martian and Venusian mesospheres. For Mars near 70 km altitude, a rotational temperature analysis using five lines gives T = 135 + or - 20 K. The frequency width of the emission is also analyzed to derive a temperature of 126 + or - 6 K. In the case of the Venusian mesosphere near 109 km, the frequency width of the emission gives T = 204 + or - 10 K
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