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Marsh, R.

Publications and source records attributed to Marsh, R..

14 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2018

Beam Imaging Diagnostic (BID) chamber blackening status March 2018

The Neutron Imaging project is using a high average power accelerator to produce a unique high flux source of neutrons. The neutron beam quality requires a small spot of deuterons on a target, which makes beam quality measurements critical to overall machine performance. Beam measurements are challenging with high average power particle beams, because the most common techniques are intercepting and the diagnostic will not survive the interaction.

43 PARTICLE ACCELERATORS↗
NASA NTRS2001

Performance and Safety of Lithium Ion Cells

This report evaluates the performance and safety of Lithium Ion (Li-Ion) cells when used in batteries. Issues discussed include the cycle life, energy efficiency, tolerance to higher charge voltage, tolerance to extended tapered charge voltage, charge on cycling, specific energy, low temperature discharge, low temperature charge, various charge characteristics, storage characteristics, and more of Li-Ion cells.

Ratnakumar, B. V.↗
NASA NTRS1999

Performance Characteristics of Lithium-Ion Cells for Mars Sample Return Athena Rover

In contrast to the primary batteries (lithium thionyl chloride) on the Sojourner Mars Rover and the upcoming 2001 Mars Rover, the Mars Sample Return (MSR) Athena Rover will utilize rechargeable lithium ion batteries, following the footsteps of MSP 2001 Lander. The MSR Athena Rover will contain a rechargeable lithium ion battery of 16 V and a total energy of 150 Wh. The mass and volume of the projected power system will be a maximum of 3 kg and 2 liters, respectively. Each battery consists of twelve cells (6-7 Ah), combined in three parallel strings of four cells (16 V) each, such that the capability of the Rover shall be maintained even in the event of one string failure. In addition to the usual requirements of high specific energy and energy density and long cycle life (100 cycles), the battery is required to operate at wide range of temperatures, especially at sub-zero temperatures down to -20 C. In this paper, we report various performance characterization tests carried out on lithium ion cells, fabricated by different manufacturers under a NASA/DoD lithium ion battery consortium.

Ratnakumar, B. V.↗
NASA NTRS1992

Results of the psychiatric, select-out evaluation of US astronaut applications

The psychiatric exclusion criteria for astronauts are based on NASA Medical Psychiatric Standards for space flight. Until recently, there were no standardized methods to evaluate disqualifying psychopathology in astronaut applicants. Method: One hundred and six astronaut applicants who had passed the intitial screening were evaluated for Axis 1 and Axis 2 DSM-3-R diagnoses using the NASA structured psychiatric interview. The interview consisted of three parts: (1) an unstructured portion for obtaining biographical and historical information, (2) the schedule for effective disorders-lifetime version (SASDL), specially modified to include all disqualifying Axis 1 mental disorders; and, (3) the personality assessment schedule (PAS) also modified to evaluate for Axis 2 disorders. Results: Nine of 106 candidates (8.5 percent) met diagnostic criteria for six Axis 1 disorders (including V code) or Axis 2 disorders. Two of these disorders were disqualifying for the applicants. 'Near' diagnoses (where applicants met at least 50 percent of the listed criteria) were assessed to demonstrate that clinicians using the interview were able to overcome applicants' reluctance to report symptomatomatology. Conclusion: The use of the NASA structured interview was effective in identifying past and present psychopathology in a group of highly motivated astronaut applicants. This was the first time a structured psychiatric interview had been used in such a setting for this purpose.

Faulk, D. M.↗
NASA NTRS1981

High energy density batteries for satellite applications

The performance requirements of high-energy batteries for terrestrial applications were examined to establish whether or not these systems showed any promise in aerospace applications. The technology assessment is reported and consists of a battery technology evaluation, preliminary engineering studies, and system selection. Major candidate systems are compared and a program schedule is provided.

Marcoux, L.↗