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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Calibration of the Advanced Very High Resolution Radiometer

Grant, Barbara Geri, 1957- January 1989 (has links)
This thesis describes the first calibration of the Advanced Very High Resolution Radiometer (AVHRR) on the NOAA-11 satellite. Two methods were used to perform the calibration. Both methods relied on calibrated data from a high resolution sensor that passed over the target site at the White Sands Missile Range, New Mexico, on November 21, 1988. The first approach required ground reflectance and atmospheric optical depth data taken during overpass time. The second method relied on historical ground reflectance data and utilized standard atmospheric models. The calibration gains varied widely depending on which set of calibration offsets were used, but the agreement between the gains computed by the two methods was very close: approximately 1% in channel 1 and 2% in channel 2. This close agreement indicates that Method 2, which does not require the complexity and expense of field work, could be a viable option for future calibration efforts.
242

Development of an adiabatic demagnetisation refrigerator for use in space

Bromiley, Paul Ann January 2000 (has links)
No description available.
243

The development of a 10 mK refrigeration system for space

Emes, Michael Robert January 2000 (has links)
No description available.
244

Correcting middle infrared cloud reflectances for atmospheric effects

Duane, William John January 1999 (has links)
No description available.
245

Investigation of the radiometric performance of the improved stratospheric and mesospheric sounder

Nightingale, Timothy John January 1992 (has links)
No description available.
246

Assembling the IGS polyhedron : a densified weekly GPS terrestrial reference frame

Davies, P. B. H. January 1997 (has links)
No description available.
247

Particulate fluxes on the Long Duration Exposure Facility

Neish, Michael Joseph January 1995 (has links)
No description available.
248

EVIDENCE FOR THE DIRECT DETECTION OF THE THERMAL SPECTRUM OF THE NON-TRANSITING HOT GAS GIANT HD 88133 b

Piskorz, Danielle, Benneke, Björn, Crockett, Nathan R., Lockwood, Alexandra C., Blake, Geoffrey A., Barman, Travis S., Bender, Chad F., Bryan, Marta L., Carr, John S., Fischer, Debra A., Howard, Andrew W., Isaacson, Howard, Johnson, John A. 23 November 2016 (has links)
We target the thermal emission spectrum of the non-transiting gas giant HD 88133 b with high-resolution near-infrared spectroscopy, by treating the planet and its host star as a spectroscopic binary. For sufficiently deep summed flux observations of the star and planet across multiple epochs, it is possible to resolve the signal of the hot gas giant's atmosphere compared to the brighter stellar spectrum, at a level consistent with the aggregate shot noise of the full data set. To do this, we first perform a principal component analysis to remove the contribution of the Earth's atmosphere to the observed spectra. Then, we use a cross-correlation analysis to tease out the spectra of the host star and HD 88133 b to determine its orbit and identify key sources of atmospheric opacity. In total, six epochs of Keck NIRSPEC L-band observations and three epochs of Keck NIRSPEC K-band observations of the HD 88133 system were obtained. Based on an analysis of the maximum likelihood curves calculated from the multi-epoch cross-correlation of the full data set with two atmospheric models, we report the direct detection of the emission spectrum of the non-transiting exoplanet HD 88133 b and measure a radial projection of the Keplerian orbital velocity of 40 +/- 15 km s(-1), a true mass of 1.02(-0.28)(+0.61) M-J, a nearly face-on orbital inclination of 15(-5)(+60), and an atmosphere opacity structure at high dispersion dominated by water vapor. This, combined with 11 years of radial velocity measurements of the system, provides the most up-to-date ephemeris for HD 88133.
249

Evaluation and testing of the Naval Postgraduate School Satellite (NPSAT1) Solar Cell Measurement System

Lo, Benson W. 09 1900 (has links)
Approved for public release; distribution is unlimited. / The Naval Postgraduate School Spacecraft Architecture and Technology Demonstration Satellite, NPSAT1, launching in the fall of 2006, will include a system to measure the performance of new experimental triplejunction solar cells. The measuring circuit in the Solar Cell Measurement System (SMS) is based on a circuit developed at the Naval Postgraduate School many years ago. It will trace the cells' current-voltage (I-V) curves while in orbit. The SMS consists of a radiation-hardened microcontroller that uses a radiation-hardened FPGA to monitor a collection of sensors. A current-sink circuit is used to measure the current and voltage on the test cells. Prior to launch, extensive testing is being performed on the system to ensure proper operation. The tests consist of subjecting solar cells and the measuring circuit electronics under conditions modeling the space environment while taking cell measurements. This thesis presents the mission information, system design, test setup, and test results of the SMS measuring circuit. / Ensign, United States Naval Reserve
250

Microwave estimates of the extratropical transitions process

Stubblefield, Cedrick L. 03 1900 (has links)
Microwave satellite imagery is a valuable tool for the observation of mature tropical cyclones. This study examined the application of microwave data to the extratropical transition (ET) process. During ET a tropical cyclone (TC) moves into an area of large gradients in many atmospheric parameters. The data sparse regions in which these gradients exist make the examination of key physical mechanisms responsible for the ET process difficult. The Advanced Microwave Sounding Unit (AMSU) was used to investigate temperature and water vapor gradients. Advanced Microwave Scanning Radiometer was used to examine WV gradients and precipitation intensities. These observations were combined with diagnostic analysis of frontogenesis during the ET process of a TC that re-intensified as an extratropical cyclone and a TC that dissipated. Although the different outcomes of ET were related to differences in coupling between the decaying TC and the midlatitude environment, microwave data were useful for defining specific characteristics that either inhibited or enhanced the coupling of the decaying TC with the midlatitude environment.

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