Evaluation of the permissible doses for exposure to ionizing radiation according to the criterion of tolerance to extreme accelerations
Permissible radiation dosage and tolerance criteria of mice to accelerations
Davydov, B. I.↗
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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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The problem of determining the permissible dose of ionizing radiation for the crew members of spacecraft
Permissible ionizing radiation dosage for spacecrews
Grigoryev, Yu. G.↗
Study of early nausea and vomiting response of swine to ionizing radiation Final technical progress report, 15 Sep. - 12 Dec. 1969
Early nausea and vomiting response of swine to ionizing radiation related to radiation dosage and effect on humans in space missions
Sullivan, M. F.↗
Crew radiation dose from a gas-core nuclear rocket plume
Crew radiation dosage from fission fragments in plume from gas core nuclear rocket
Masser, C. C.↗
A preliminary analysis of the radiation burden of a typical Mars lander mission
Predicted radiation dosage for Mars lander mission
Dugan, V. L.↗
The effects of charged particle and UV radiation on the stability of silvered and aluminized FEP Teflon second surface mirrors
Determining solar absorptance stability of metallized Teflon second surface mirror thermal control coatings as function of electron, proton, and UV radiation dosage
Wappaus, W. A.↗
Radiation hazard from backflow of fission fragments from the plume of a gas core nuclear rocket
Calculation of crew radiation dosage from uranium gas nuclear rocket engine exhaust backflow of fission products
Masser, C. E.↗
Computerized anatomical model man for analyses of radiation doses
Computerized human body anatomical geometrical model with life size skeleton and organs scaling for radiation dosage analyses in space missions
Kase, P. G.↗
Modular space station phase B extension preliminary system design. Volume 5: configuration analyses
The initial and growth modular space station configurations are described, and the evolutionary steps arriving at the final configuration are outlined. Supporting tradeoff studies and analyses such as stress, radiation dosage, and micrometeoroid and thermal protection are included.
Stefan, A. J.↗
Advanced research to qualify man for long term weightlessness.
NASA is in the process of conducting a broad program of research and development of technology to qualify, support, and permit the successful use of man in long-term space flight. The technological tasks include human engineering, extravehicular engineering, life support, and human research to assess the effect of space stresses on human physiology and psychology. Various testing techniques that are being used may have future relevance to world health. These include a biocybernetic approach to the study of cardiovascular stresses, measurement of blood flow by means of the Doppler effect, and a device for simulating radiation dosages similar to those produced in solar flares. The planned program includes a study of both humans and animals.
Jones, W. L.↗
Magnetospheric modulation effects on solar cosmic rays from simultaneous OGO 1 and 3 ion chamber data in 1968 and 1969
Simultaneous observations by identical ionization chambers aboard the satellites OGO-1 and OGO-3 are utilized to investigate spatial variations in particle intensity near and inside the magnetosphere during the solar cosmic ray events of September 1966. Cross-correlation of the absolute proton flux computed from the chamber rate during three solar particle events shows good agreement with the measurements by the IMP-F Solar Proton Monitor during the same events. The chamber has a dynamic range of over six orders of magnitude. Before launch it was calibrated in the laboratory with radiation dosages in the range 1 R/hr-6000 R/hr. The OGO-1 and OGO-3 chambers, which were normalized in the laboratory prior to the launch, are found to maintain their normalization within approximately equal to 1 per cent during their flight. The high sensitivity and absolute inter-comparability of the instruments allow small intensity differences to be detected and it is established that the observed differences can be explained by a magnetospheric screening effect when an anisotropic beam of particles is present in space. Evidence is presented to show that the screening is at times complete for a duration of as much as 110 min in the tail of the magnetosphere so that during this period the solar cosmic rays (E approximately equal to 15 MeV) have virtually no access to that region of the magnetosphere. Small intensity fluctuations of a temporal nature observed and found to be subjected to a damping effect inside the magnetosphere.
Hofmann, D. J.↗
Implementation of a stereofluoroscopic system
Clinical applications of a 3-D video imaging technique developed by NASA for observation and control of remote manipulators are discussed. Incorporation of this technique in a stereo fluoroscopic system provides reduced radiation dosage and greater vision and mobility of the user.
Rivers, D. B.↗
Summary of problems of greatest urgency
A description is presented of the activities which would be important in connection with the objective to find a course of action to achieve permanent occupancy of space. One of the technical problems to be solved is related to the development of a closed ecological system in space. Lunar material transportation and collection is a second major problem. The development of either automated, manned, or mixed construction technologies for the assembly of large structures in space is also important. Attention is also given to the design of the habitat, the need for a better understanding of the genetic effects of an increased radiation dosage over long periods of time, and the current status of space activities.
Freitag, R. F.↗
Dosimetric considerations in dental applications
The integration of the Lixiscope into dental procedures was studied and compared with conventional dental radiographic techniques. It was found that through the use of intraoral sealed sources in conjunction with microchannel plate technology, the Lixiscope gives increased diagnostic information with decreased radiation dosage.
Goble, J. C.↗
Solar-Terrestrial Predictions Proceedings. Volume 2: Working Group Reports and Reviews
Accurate models are needed to support research in the following areas: spacecraft charging, radiation dosage, transionospheric radio propagation, long and short term solar activity, magnetospheric disturbances, ionospheric interactions, solar weather/climate effects, and geomagnetic applications such as electric power transmission and oil and gas pipeline problems.
Richard F Donnelly↗
A very high speed lossless compression/decompression chip set
A chip is described that will perform lossless compression and decompression using the Rice Algorithm. The chip set is designed to compress and decompress source data in real time for many applications. The encoder is designed to code at 20 M samples/second at MIL specifications. That corresponds to 280 Mbits/second at maximum quantization or approximately 500 Mbits/second under nominal conditions. The decoder is designed to decode at 10 M samples/second at industrial specifications. A wide range of quantization levels is allowed (4...14 bits) and both nearest neighbor prediction and external prediction are supported. When the pre and post processors are bypassed, the chip set performs high speed entropy coding and decoding. This frees the chip set from being tied to one modeling technique or specific application. Both the encoder and decoder are being fabricated in a 1.0 micron CMOS process that has been tested to survive 1 megarad of total radiation dosage. The CMOS chips are small, only 5 mm on a side, and both are estimated to consume less than 1/4 of a Watt of power while operating at maximum frequency.
Venbrux, Jack↗
Martian regolith as space radiation shielding
Mars exploration crews will be exposed to such high radiation dosages in route from earth that as to sharply reduce the allowable dose they should receive while on the Martian surface. An account is presently given of the possibility of using Martian regolith as crew shielding to maintain very low short-term dose limits. NASA-Langley's nucleon and heavy-ion transport computer codes are used to predict the propagation and interaction of the free-space nucleons and heavy ions through the Martian atmosphere and then through various thicknesses of regolith. The largest reduction in dose occurs in the first 15-20 cm of regolith material.
Simonsen, L. C.↗
PASP Plus: An experiment to measure space-environment effects on photovoltaic power subsystems
The Photovoltaic Array Space Power Plus Diagnostic experiment (PASP Plus) was accepted as part of the APEX Mission payload aboard a Pegastar satellite to be orbited by a Pegasus launch vehicle in late 1992. The mission's elliptical orbit will allow us to investigate both space plasma and space radiation effects. PASP Plus will have eleven types of solar arrays and a full complement of environmental and interactions diagnostic sensors. Measurements of space-plasma interactions on the various solar arrays will be made at large negative voltages (to investigate arcing parameters) and at large positive voltages (to investigate leakage currents) by biasing the arrays to various levels up to -500 and +500 volts. The long-term deterioration in solar array performance caused by exposure to space radiation will also be investigated; radiation dosage will be measured by an electron/proton dosimeter included in the environmental sensor complement. Experimental results from PASP Plus will help establish cause-and-effect relationships and lead to improved design guidelines and test standards for new-technology solar arrays.
Guidice, Donald A.↗