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All sourcesNASA NTRSDOE OSTI
NASA NTRS2004

Collaborative Engineering for Research and Development

Research and development (R&D) organizations are being required to be relevant, to be more application-oriented, and to be partners in the strategic management of the business while meeting the same challenges as the rest of the organization, namely: (1) reduced time to market; (2) reduced cost; (3) improved quality; (4) increased reliability; and (5) increased focus on customer needs. Recent advances in computer technology and the Internet have created a new paradigm of collaborative engineering or collaborative product development (CPD), from which new types of relationships among researchers and their partners have emerged. Research into the applicability and benefits of CPD in a low/no production, R&D, and/or government environment is limited. In addition, the supply chain management (SCM) aspects of these relationships have not been studied. This paper presents research conducted at the NASA Glenn Research Center (GRC) investigating the applicability of CPD and SCM in an R&D organization. The study concentrates on the management and implementation of space research activities at GRC. Results indicate that although the organization is engaged in collaborative relationships that incorporate aspects of SCM, a number of areas, such as development of trust and information sharing merit special attention.

Davis, Jose M.↗
NASA NTRS2004

Collaborative Product Development in an R&D Environment

Research and development (R&D) organizations are being required to be relevant, to be more application-oriented, and to be partners in the strategic management of the business while meeting the same challenges as the rest of the organization, namely: (1) reduced time to market; (2) reduced cost; (3) improved quality; (4) increased reliability; and (5) increased focus on customer needs. Recent advances in computer technology and the Internet have created a new paradigm of collaborative engineering or collaborative product development (CPD), from which new types of relationships among researchers and their partners have emerged. Research into the applicability and benefits of CPD in a low/no production, R&D, and/or government environment is limited. In addition, the supply chain management (SCM) aspects of these relationships have not been studied. This paper presents research conducted at the NASA Glenn Research Center (GRC) investigating the applicability of CPD and SCM in an R&D organization. The study concentrates on the management and implementation of space research activities at GRC. Results indicate that although the organization is engaged in collaborative relationships that incorporate aspects of SCM, a number of areas, such as development of trust and information sharing merit special attention.

Davis, Jose M.↗
NASA NTRS1982

Relationships between the Birkeland currents, ionospheric currents, and electric fields

Currents and electric fields in the ionosphere are calculated using a global model of the electron density including conjugate coupling along field lines. Incoherent scatter and rocket measurements of high-latitude electron densities are used to derive realistic variations of the polar conductivities as a function of magnetic activity. The Birkeland currents are specified in terms of three indices, and the relationship between these parameters and the auroral electrojets indices is examined along with the polar cap potential and the electric field at lower latitudes. A mathematical model of the currents, electric fields, and energy inputs produced by field aligned currents is developed, which is consistent with and specifiable in terms of measured geophysical indices.

Bleuler, E.↗
NASA NTRS2002

Food-anticipatory activity and liver per1-luc activity in diabetic transgenic rats

The mammalian Per1 gene is an important component of the core cellular clock mechanism responsible for circadian rhythms. The rodent liver and other tissues rhythmically express Per1 in vitro but typically damp out within a few cycles. In the liver, the peak of this rhythm occurs in the late subjective night in an ad lib-fed rat, but will show a large phase advance in response to restricted availability of food during the day. The relationship between this shift in the liver clock and food-anticipatory activity (FAA), the circadian behavior entrained by daily feeding, is currently unknown. Insulin is released during feeding in mammals and could serve as an entraining signal to the liver. To test the role of insulin in the shift in liver Per1 expression and the generation of FAA, per-luciferase transgenic rats were made diabetic with a single injection of streptozotocine. Following 1 week of restricted feeding and locomotor activity monitoring, liver was collected for per-luc recording. In two separate experiments, FAA emerged and liver Per1 phase-shifted in response to daytime 8-h food restriction. The results rule out insulin as a necessary component of this system.

NASA Discipline Space Human Factors↗
NASA NTRS1974

Crew/computer communications study. Volume 2: Appendixes

The software routines developed during the crew/computer communications study are described to provide the user with an understanding of each routine, any restrictions in use, the required input data, and expected results after executing the routines. The combination of routines to generate a crew/computer communications application is also explained. The programmable keyboard and display used by the program is described, and an experiment scenario is provided to illustrate the relationship between the program frames when they are grouped into activity phases. Program descriptions and a user's guide are also presented. For Vol. 1, see N74-18843.

Johannes, J. D.↗
NASA NTRS1974

Ar-40/Ar-39 chronology and cosmic ray exposure ages of the Apollo 15 samples

The Ar-40*/Ar-39* thermal release patterns of igneous soil fragments, rake basalts, and large crystalline rocks are by and large well defined. Shock deformations of up to moderate intensities have no observable effects on the Ar-40*/Ar-39* release patterns. Neither do the Ar-40* diffusion losses have any relationship with the shock intensities. The peak of the magnetic activity in Palus Putredinis occurred at 3.33 plus or minus 0.02 Gy, lava flows continuing up to 3.13 Gy but at much reduced intensity. No correlation between the crystallization ages and the petrographic rock types was observed. The cosmic ray exposure gas indicate a mature regolith around the Hadley Rille-Apennine Front region. The exposure ages of the Apollo 15 samples cannot reliably be used to obtain the time of prominent cratering events at this site.

Husain, L.↗
NASA NTRS1979

General properties of HII regions in galaxies

The structure, electron density, and dimensions of HII regions in galaxies are discussed. These parameters are correlated to the chemical composition gradient along the galactic radius, the dimensions of the three largest HII regions in the galaxy, and the amount of hydrogen in the galaxy, as well as the mass, dimensions, and total optical luminosity of the galaxy. The relationships of HII regions to star formation and galactic nucleus activity are discussed and the kinematic properties of the SB and Sab galaxies are related to the size of HII regions.

Smirnov, M. A.↗
NASA NTRS1979

Satellite measurements of earth radiation budget for climate applications

Understanding the global balance between the absorption of solar radiation and the emission of longwave radiation is considered pivotal to understanding the processes which govern the earth's climate. In concert with a large scientific community interested in the earth's radiation budget, NASA has initiated a program to accurately determine the spatial and temporal characteristics of the earth's radiation budget. This program will utilize instrumentation placed on three satellites including the Space Shuttle-launched free flying Earth Radiation Budget Satellite. The program is discussed relative to its scientific background, plans for the Earth Radiation Budget Experiment, and the relationship of this effort to present and future climate research activities.

Curran, R. J.↗
NASA NTRS1981

Solar observations

High energy processes that take place in the Sun's atmosphere and the relationship of these phenomena to the basic problems of solar activity are discussed. Gamma ray emission exhibits characteristics of the conditions in regions where accelerated high energy particles interact. A number of gamma ray production mechanisms are considered. These include: the Compton effect, magnetobremsstrahlung, pi meson production by proton-proton interaction or by proton-antiproton annihilation, fission and neutral of charged particle radiative capture on inelastic scatter.

Source record↗
NASA NTRS1985

Interannual variability of middle atmosphere during northern winter

An investigation was undertaken to examine the characteristics of the interannual variability of the zonal wind and the temperature of the middle atmosphere of the Northern Hemisphere during winter and to search for a relationship of the variability of the middle atmosphere with the activity of the following Indian summer monsoon. For this purpose, the rocketsonde temperature and wind data for 8 stations for a 6-year period for the month of January were collected. It is clear from the results that the interannual variability noticed in the zonal wind of the high latitude middle atmosphere was caused by the differential activity of the long-period planetary waves. In order to examine whether the stability of the polar night jet in the high latitude middle atmosphere has any influence on the spectacular tropospheric weather phenomenon such as the Indian summer monsoon, the rainfall activity for India has been studied. The study revealed that: (1) the strong and stable polar night jet with weak equator to pole temperature gradient at the stratopause in January was linked with the forthcoming weak monsoon activity; and (2) the weak and distorted polar night jet with strong equator-to-pole temperature gradient at the stratopause in January was linked with the forthcoming strong monsoon activity.

Mukherjee, B. K.↗
NASA NTRS1988

The far-ultraviolet spectra of early-type galaxies

New and revised ultraviolet energy distributions ar presented based on 97 IUE spectra of 31 early-type galaxies and the bulge of M31. Based on optical spectra and morphology, the sample galaxies are divided into star-forming galaxies, active galaxies, and quiescent galaxies. A well-defined nonlinear relationship between (1550-V) color and Mg2 for the 24 quiescent galaxies is obtained. The ultraviolet spectra of these galaxies can be modeled as a sum of two components: a normal, cool stellar population of main-sequence and giant branch stars that is redder at high Mg2, plus a very blue population having a steeply rising UV flux below 2000 A that increases in strength with metallicity. The UV spectra of star-forming galaxies are significantly flatter than the very blue component of quiescent galxies and are consistent with aging bursts of star formation. Two sample population models are explored for the blue stellar component of quiescent galaxies: postasymptotic giant branch stars and young stars from continuing star formation.

Burstein, David↗
NASA NTRS1989

Controlled Ecological Life Support System Breadboard Project - 1988

The Controlled Ecological Life Support System (CELSS) Breadboard Project, NASA's effort to develop the technology required to produce a functioning bioregenerative system, is discussed. The different phases of the project and its current status are described. The relationship between the project components are shown, and major project activities for fiscal years 1989-1993 are listed. The biomass production chamber to be used by the project is described.

Knott, W. M.↗
NASA NTRS1991

Closed-form solutions for linear regulator design of mechanical systems including optimal weighting matrix selection

Vibration in modern structural and mechanical systems can be reduced in amplitude by increasing stiffness, redistributing stiffness and mass, and/or adding damping if design techniques are available to do so. Linear Quadratic Regulator (LQR) theory in modern multivariable control design, attacks the general dissipative elastic system design problem in a global formulation. The optimal design, however, allows electronic connections and phase relations which are not physically practical or possible in passive structural-mechanical devices. The restriction of LQR solutions (to the Algebraic Riccati Equation) to design spaces which can be implemented as passive structural members and/or dampers is addressed. A general closed-form solution to the optimal free-decay control problem is presented which is tailored for structural-mechanical system. The solution includes, as subsets, special cases such as the Rayleigh Dissipation Function and total energy. Weighting matrix selection is a constrained choice among several parameters to obtain desired physical relationships. The closed-form solution is also applicable to active control design for systems where perfect, collocated actuator-sensor pairs exist.

Hanks, Brantley R.↗
NASA NTRS1990

Controlled ecological life support system breadboard project, 1988

The Closed Ecological Life Support System (CELSS) Breadboard Project, NASA's effort to develop the technology required to produce a functioning bioregenerative system, is discussed. The different phases of the project and its current status are described. The relationship between the project components are shown, and major project activities for fiscal years 1989 to 1993 are listed. The Biomass Production Chamber (BPC) became operational and tests of wheat as a single crop are nearing completion.

Knott, W. M.↗
NASA NTRS1991

Closed-form solutions for linear regulator-design of mechanical systems including optimal weighting matrix selection

This paper addresses the restriction of Linear Quadratic Regulator (LQR) solutions to the algebraic Riccati Equation to design spaces which can be implemented as passive structural members and/or dampers. A general closed-form solution to the optimal free-decay control problem is presented which is tailored for structural-mechanical systems. The solution includes, as subsets, special cases such as the Rayleigh Dissipation Function and total energy. Weighting matrix selection is a constrained choice among several parameters to obtain desired physical relationships. The closed-form solution is also applicable to active control design for systems where perfect, collocated actuator-sensor pairs exist. Some examples of simple spring mass systems are shown to illustrate key points.

Hanks, Brantley R.↗
NASA NTRS1991

A three dimensional radiative transfer method for optical remote sensing of vegetated land surfaces

In the application of remote sensing at optical wavelengths to vegetated surfaces from satellite borne high resolution instruments, an understanding of the various physical mechanisms that contribute to the measured signal is important. A numerical method of solving the radiative transfer equation in three dimensions is reported. The reliability of coding and accuracy of the algorithm are evaluated by benchmarching. Parametrization of the methods and results of a simulation are presented. The method is tested with experimental data of canopy bidirectional reflectance factors. The effect of spatial heterogeneity on the relationship between the simple ratio and normalized vrs absorbed Photosynthetically Active Radiation (PAR) is discussed.

Asrar, Ghassem↗
NASA NTRS1992

Workshop on Solar Activity, Solar Wind, Terrestrial Effects, and Solar Acceleration

A summary of the proceedings from the workshop are presented. The areas covered were solar activity, solar wind, terrestrial effects, and solar acceleration. Specific topics addressed include: (1) solar cycle manifestations, both large and small scale, as well as long-term and short-term changes, including transients such as flares; (2) sources of solar wind, as identified by interplanetary observations including coronal mass ejections (CME's) or x-ray bright points, and the theory for and evolution of large-scale and small-scale structures; (3) magnetosphere responses, as observed by spacecraft, to variable solar wind and transient energetic particle emissions; and (4) origin and propagation of solar cosmic rays as related to solar activity and terrestrial effects, and solar wind coronal-hole relationships and dynamics.

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NASA NTRS1997

Education and Training Report. Performance Report, FY 1997

During FY 97, 152 MUREP education and training projects were conducted at OMU institutions. The institutions conducted precollege and bridge programs, education partnerships with other universities and industry, NRTS, teacher training, and graduate and/or PI undergraduate programs. These programs reached a total of 23,748 participants, with the predominant number at the precollege level and achieved major goals of heightening students' interest and awareness of career opportunities in MSET fields, and exposing students to the NASA mission, research and advanced technology through role models, mentors, and participation in research and other educational activities. Also in FY 1997, NASA continued a very meaningful relationship with the Hispanic Association of Colleges students and Universities (HACU) through Proyecto Access, a consortium through which HACU links seven HSI's together to conduct 8-week summer programs. OMU Institutions reported 4,334 high school student in NASA programs and 3,404 of those students selected college preparatory MSET courses. Three hundred and forty-nine (349) graduated from high school, 343 enrolled in college, and 199 selected MSET majors. There were 130 high school graduates (bridge students) in NASA programs, 57 of whom successfully completed their freshman year. There were 307 teachers in teacher programs and 48 teachers received certificates. Of the 389 undergraduate students, 75 received under graduate degrees, and eight students are employed in a NASA-related field.

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