NASA/American Society for Engineering Education (ASEE) Summer Faculty Fellowship Program 1989

Since 1964, NASA has supported a program of summer faculty fellowships for engineering and science educators. The objectives are: to further the professional knowledge of qualified engineering and science faculty; to stimulate and exchange ideas between participants and NASA; to enrich and refresh the research and teachning activities of participants' institutions; and to contribute to the research objectives of the NASA center. College or university faculty members will be appointed as Research Fellows to spend 10 weeks in cooperative research and study at the NASA Langley Research Center. The Fellow will devote approximately 90 percent of the time to a research problem and the remaining time to a study program. The study program will consist of lecture and seminars on topics of interest or that are directly relevant to the Fellows' research topic

Orbital transfer vehicle launch operations study: Automated technology knowledge base, volume 4

A simplified retrieval strategy for compiling automation-related bibliographies from NASA/RECON is presented. Two subsets of NASA Thesaurus subject terms were extracted: a primary list, which is used to obtain an initial set of citations; and a secondary list, which is used to limit or further specify a large initial set of citations. These subject term lists are presented in Appendix A as the Automated Technology Knowledge Base (ATKB) Thesaurus

Engineering handbook

1996 handbook for the faculty of Engineerin

Towards optimal control of fuel cell hybrid electric vehicles

Global warming, the decline of natural resources as well as the strengthening of emission regulations have led to a research focus in new drive technologies. Within the group of alternative propulsion systems, fuel cell hybrid electric vehicle (FHEV) are considered especially promising. Since system efficiency as well as the operation characteristics are determined by the chosen energy management system (EMS) scheme, an optimal approach is a key aspect to guarantee optimal system operation in terms of power and energy efficiency, as well as component lifetime and costs. Existing research efforts mostly focus on the optimisation of the hydrogen consumption, while neglecting component degradation as additional important part of total system and operation cost. Furthermore, almost no published work considers the thermal management of a FHEV. Therefore, the presented work propose a novel model predictive control based energy management approach with a special focus on preventing fuel cell (FC) and battery (BAT) degradation and the vehicle’s thermal management. In order to minimise component ageing and degradation, the objective function which is used in the developed method, includes cost which account for both decreasing BAT state of health as well as FC operation conditions which accelerate the degradation of the FC. To be able to test the developed EMS, a model and a hardware based test environment were developed. Since there are no thermal management systems for FHEV presented in literature, a new concept with a hierarchical control scheme was designed. Because the newly developed energy management shall be tested based on real world data, a method to generate test cases representing typical driving scenarios based on real world driving data was developed and implemented. Finally, the hardware system was used to validate the simulation model and vice versa, the model based approach was validated on real hardware

REAL-TIME SIGNAL PROCESSING FOR FLYING HEIGHT MEASUREMENT AND CONTROL IN HARD DRIVES SUBJECT TO SHOCK AND VIBRATION

Merged with duplicate record 10026.1/829 on 10.04.2017 by CS (TIS)Three readback signal detection methods are investigated for real-time flying height or head disk spacing variation measurement under vibration conditions. This is carried out by theoretical analysis, numerical simulation, and experimental study. The first method (amplitude detection) provides a simple way to study the head disk spacing change. The second method ( PW50 parameter estimation) can be used effectively for real-time spacing variation measurement in normally operated hard disk drives, primarily in low frequency spacing variation conditions. The third method (thermal signal detection), on the other hand, is more effective and suitable for high frequency spacing variation measurement. By combining the PW50 estimation and thermal signal detection methods, a noval spacing variation detection method for the whole frequency range is constructed. This combined signal detection method not only has been used to study the head disk spacing variation itself, but also has the potential of being used for real time flying height control. Analytical models are developed for head disk assembly and head position servo control mechanisms to analyse the operation failure of hard disk drives under vibration conditions. Theoretical analysis and numerical simulation show their good agreement with experimental results. A novel active flying height control method is proposed to suppress the flying height or head-disk spacing variation in hard disk drives under vibration conditions. Simulation results show that this active flying height control can effectively suppress the head-disk spacing variation, therefore the performance and reliability of HDDs can be well improved when working in vibration conditions: The method has a good potential to be applied to future ruggedized hard disk drives

The 2004 NASA Faculty Fellowship Program Research Reports

This is the administrative report for the 2004 NASA Faculty Fellowship Program (NFFP) held at the George C. Marshall Space Flight Center (MSFC) for the 40th consecutive year. The NFFP offers science and engineering faculty at U.S. colleges and universities hands-on exposure to NASA s research challenges through summer research residencies and extended research opportunities at participating NASA research Centers. During this program, fellows work closely with NASA colleagues on research challenges important to NASA's strategic enterprises that are of mutual interest to the fellow and the Center. The nominal starting and .nishing dates for the 10-week program were June 1 through August 6, 2004. The program was sponsored by NASA Headquarters, Washington, DC, and operated under contract by The University of Alabama, The University of Alabama in Huntsville, and Alabama A&M University. In addition, promotion and applications are managed by the American Society for Engineering Education (ASEE) and assessment is completed by Universities Space Research Association (USRA). The primary objectives of the NFFP are to: Increase the quality and quantity of research collaborations between NASA and the academic community that contribute to the Agency s space aeronautics and space science mission. Engage faculty from colleges, universities, and community colleges in current NASA research and development. Foster a greater public awareness of NASA science and technology, and therefore facilitate academic and workforce literacy in these areas. Strengthen faculty capabilities to enhance the STEM workforce, advance competition, and infuse mission-related research and technology content into classroom teaching. Increase participation of underrepresented and underserved faculty and institutions in NASA science and technology

Environmental Modeling Under Uncertainty: Monte Carlo Simulation

The study of environmental systems as ecological and physicochemical as well as socioeconomic entities requires a high degree of simplifying formalism. However, a detailed understanding of a systems function and response to various changes for the explicit purpose of systems management and planning still requires fairly complex hypotheses, or models. Such models can hardly be subjected to rigorous tests without the aid of computers. Systems simulation is a powerful tool when subjecting complex hypotheses to critical tests of their logical structure and their performance over the range of plausible input conditions . Based on a formalized trial-and-error approach using Monte Carlo methods, this report presents and discusses an approach to simulation modeling under uncertainty. An introduction to the causes and implications of the problem, namely uncertainty, and a short formal presentation of the methodology proposed are followed by some more technical remarks on Monte Carlo simulation. Using three different application examples, the author discusses the role of uncertainty in the formal testing of model structures, in parameter estimation, and in prediction. In the last example, the limits of estimation and, with it, prediction are demonstrated. In a comparison of Monte Carlo simulation and alternative approaches to including and evaluating uncertainty in simulation modeling, the discussion section examines the implications of uncertainty for model application in a broader framework