418 research outputs found

    Department of Geology/NASA-GSFC geobotanical investigation

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    Geobotanical mapping in the southern Appalachians and soil metal associated changes in vegatation spectral responses in the reflective and emissive portions of the electromagnetic spectrum (EMS) is studied. It is determined whether deciduous forest vegetation reflection and emission characteristics show detectable changes that can be related to residual soil characteristics. Analyses of such related characteristics enhances the ability to discriminate underlying lithologies as well as variances within lithologies associated with natural heavy metal occurences. An understanding is developed of the factors which contribute to the differing spectral signatures of various lithology/soil types. A combination of field data and remote spectral analysis is studied

    Evaluation of Raytek infrared pyrometer for continuous propellant temperature measurement

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    The primary purpose of this evaluation was to determine if the Raytek IR pyrometer that was installed in the 600 gallon propellant mixers could be used to provide a continuous, accurate, reliable measurement of the propellant temperature during mixing. The Raytek infrared sensor is not recommended to be used for controlling propellant temperature nor for inspection buy-off. The first part of the evaluation was to determine the accuracy of the sensor in measuring the propellant temperature. The second part was to determine the reliability of the air purge design in preventing contamination of the IR window

    Analyzing interference between RGB-D cameras for human motion tracking

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    Multi-camera RGB-D systems are becoming popular as sensor setups in Computer Vision applications but they are prone to cause interference between them, compromising their accuracy. This paper extends previous works on the analysis of the noise introduced by interference with new and more realistic camera configurations and different brands of devices. As expected, the detected noise increases as distance and angle grows, becoming worse when interference is present. Finally, we evaluate the effectiveness of the proposed solutions of using DC vibration motors to mitigate them. The results of this study are being used to assess the effect of interference when applying these setups to human motion tracking.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Plan Propio de Investigación de la UMA. Junta de Andalucía, proyecto TEP2012-53

    Radiative Heat Transfer Analysis of Railroad Bearings for Wayside Thermal Detector Optimization

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    Wayside hot-box detectors (HBDs) are devices that are currently used to evaluate the health of railcar components including bearings, axles, and brakes by monitoring their temperatures. While HBDs have been instrumental in reducing some train derailments in the past few decades, the number of non-verified bearing removals has increased significantly. In general, HBDs tend to underestimate bearing temperatures in both field service and in laboratory testing, which is not surprising considering the simple two-point calibration method that is used to calibrate these devices. Because of this, different calibrations were compared and analyzed including two-point, three-point, and multi-point calibrations. Analysis of the results also suggests that the scanning location significantly affects the temperature measurement. The work in this thesis summarizes how an optimized calibration technique along with proper IR sensor alignment can markedly improve the accuracy and precision of HBD temperature measurements

    High temperature superconducting infrared imaging satellite

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    A low earth orbiting platform for an infrared (IR) sensor payload is examined based on the requirements of a Naval Research Laboratory statement of work. The experiment payload is a 1.5-meter square by 0.5-meter high cubic structure equipped with the imaging system, radiators, and spacecraft mounting interface. The orbit is circular at 509 km (275 nmi) altitude and 70 deg. inclination. The spacecraft is three-axis stabilized with pointing accuracy of plus or minus 0.5 deg. in each axis. The experiment payload requires two 15-minute sensing periods over two contiguous orbit periods for 30 minutes of sensing time per day. The spacecraft design is presented for launch via a Delta 2 rocket. Subsystem designs include attitude control, propulsion, electric power, telemetry, tracking and command, thermal design, structure, and cost analysis

    Pigeonhole notification system by utilizing telegram messenger

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    Pigeonhole Notification System by Utilizing Telegram Messenger is one system was built using simple embedded system and Telegram Messenger one type of mobile messaging client. Pigeonhole Notification System by Utilizing Telegram Messenger is aim to help Faculty of Computer Systems & Software Engineering (FSKKP) lecturers to get notification about the present of mails into their pigeonholes. In addition, this system also will give warning notification if the volumes of their pigeonhole already reach certain level of fullness. Every notification will directly sent to user Telegram Messenger account and user will access in multiple platform depends on user devices such as Android base device, Windows base device, OS X base device, or Linux base device

    Polarization-Tunable Antenna-Coupled Infrared Detector

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    An antenna-coupled infrared detector with polarization tuning over approximately 90 degrees by application of a bias voltage in the range of a few hundred millivolts. This mechanism of polarization tuning eliminates the need for bulk-optical polarization filters. When integrated into focal plane arrays, these detectors can be used in remote-sensing systems to facilitate enhanced image recognition, feature extraction and image-clutter removal. A preferred version of the antenna has longitudinal metal antenna arms extending outward from an infrared(IR) sensor in a spiral pattern, polarization tuning devices connected between the antenna arms, and a voltage for controlling the polarization tuning devices, wherein the polarization tuning devices enable real-time control of current distribution in the arms. The infrared(IR) sensors can be tunnel diodes, schottky diodes, photovoltaics, photoconductors, and pyroelectrics. Application areas can include earth-resource mapping, pollution monito

    Wavelength Tunable Antenna Coupled Infrared Detectors

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    A tuned antenna-coupled infrared detector is made possible by application of a bias voltage in the range of a few hundred millivolts. The use of first and second antenna arms connected to the detector makes possible polarization tuning which eliminates the need for bulk-optical polarization filters. An alternative tuned detector is one in which the antenna is frequency tuned by a capacitative device to make the detector particularly responsive to 8 um to 12 um infrared radiation. When integrated into focal plane arrays, these detectors can be used in remote-sensing systems to facilitate enhanced image recognition, feature extraction and image-clutter removal. One preferred version of the polarization tuned antenna has longitudinal metal antenna arms extending outward from an infrared(IR) sensor in a spiral pattern, with polarization tuning devices connected between the antenna arms, and a voltage for controlling the polarization tuning devices, wherein the polarization tuning devices
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