Engineering Papers⌕ Search

Engineering topics

Walker, J. D.

Publications and source records attributed to Walker, J. D..

5 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1980

NASA PERT time II

Program Evaulation and Review Technique (PERT) is disciplined management technique involving computer processing. NASA PERT Time 11 gives project manager insight into current and future project development and forewarns of potential problems. Program utilizes modular technique. Module is "fragnet"; once aspects of project are described in terms of fragnets, control network is automatically generated. Program is written in FORTRAN IV and OS Assembler for batch execution and has been implemented on IBM 370.

Bainbridge, R. C.↗
NASA NTRS1976

Behavior of the sodium and hydroxyl nighttime emissions during a stratospheric warming

The behavior of the sodium and hydroxyl nighttime emissions during a stratospheric warming has been studied principally by use of data from the airglow photometers on the OGO 4 satellite. During the late stages of a major warming, both emissions increased appreciably, with the sodium emission returning to normal values prior to the decrease in the hydroxyl emission. The emission behaviors are attributed to temperature and density variations from 70 to 94 km, and a one-dimensional hydrostatic model for that altitude range is used to calculate the effects on the emissions and on the mesospheric ozone densities. These results support the existence of a warming in the upper part of the mesosphere that is correlated with a major stratospheric warming.

Walker, J. D.↗
NASA NTRS1975

Behavior of the sodium and hydroxyl nighttime emissions during a stratospheric warming

The behavior of the sodium and hydroxyl nighttime emissions during a stratospheric warming has been studied principally by use of data from the airglow photometers on the OGO-4 satellite. It was found that during the late stages of a major warming, both emissions increase appreciably, with the sodium emission returning to normal levels prior to the decrease in hydroxyl emission. The emission behaviors are attributed to temperature and density variations from 70 to 94 km, and a one-dimensional hydrostatic model for that altitude range is used to calculate the effects on the emissions and on the mesospheric ozone densities.

Walker, J. D.↗
NASA NTRS1967

Computer/PERT technique monitors actual versus allocated costs

A computer method measures the users performance in cost-type contracts utilizing the existing nasa program evaluation review technique without imposing any additional reporting requirements. progress is measured by comparing actual costs with a value of work performed in a specific period.

Houry, E.↗