We have developed a new technique based on the passive gamma method for measuring a quantity of uranium in a uranium waste container (1200 liter volume). The measurement system consists of three NaI (Tl)detectors, one High Purity Germanium (HPGe) detector and a handling system. The measuring method uses two discrete gamma-ray energies emitted from the daughter nuclide Pa-234m (1001 keV and 766 ...

In this report, ultraviolet (UV) detectors were fabricated based on zinc oxide thin films. The epitaxial growth of zinc oxide thin films was carried out on bare glass substrate with preferred orientation to (002) plane of wurtzite structure through radio frequency sputtering technique. The structural properties indicated a dominant peak at 2θ=34.28º which was matched with JCPDS reference card N...

Background: Estimating dosimetric parameters for small fields under non-reference conditions leads to significant errors if done based on conventional protocols used for large fields in reference conditions. Hence, further correction factors have been introduced to take into account the influence of spectral quality changes when various detectors are used in non-reference conditions at differen...

The Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) was installed in the Hubble Space Telescope in February 1997. After twenty-two months of operation the 110 kg supply of solid N2, which cooled the NICMOS-3 HgCdTe detectors, was exhausted. The cryostat warmed up leaving the instrument in an electromechanically functional, but scientifically non-viable, passive state. Following a th...

[1] To provide validation of the ICESat laser altimeter time of measurement and geolocation, a ground-based technique was implemented at White Sands Space Harbor (WSSH), during the Laser 2a and 3a operational periods. The activities used an electro-optical detection system and a passive array of corner cube retro reflectors (CCR). The detectors and the CCRs were designed to provide an independe...

Several authors have proposed that motion is analyzed by two separate processes: short-range and long-range. We claim that the differences between short-range and long-range motion phenomena are a direct consequence of the stimuli used in the two paradigms and are not evidence for the existence of two qualitatively different motion processes. We propose that a single style of motion analysis, s...

A reliable radiation risk assessment in space is a mandatory step for the development of countermeasures and long-duration mission planning in human spaceflight. Research in radiobiology provides information about possible risks linked to radiation. In addition, for a meaningful risk evaluation, the radiation exposure has to be assessed to a sufficient level of accuracy. Consequently, both the ...