Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “User Facility”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 217 records · Page 12

Power management for multi-100 KWe space systems

This paper examines mid to late 1980s power management technology needs to support development of a general-purpose space platform, capable of supplying 100 to 250 KWe to a variety of users in LEO. To that end, a typical Shuttle-assembled and supplied space platform is described, along with a group of payloads which might reasonably be expected to use such a facility. Examination of platform and user power needs yields a set of power system requirements used to evaluate power management options for life cycle cost effectiveness. The most cost-effective AC/DC and DC systems are evaluated, specifically to develop system details which lead to technology goals including array and transmission voltage, best frequency for AC power transmission, and advantages and disadvantages of AC and DC systems for this application. Finally, system and component requirements are compared with the state of the art to identify areas where technology development is required.

Mildice, J. W.↗

Differential collision cross-sections for atomic oxygen: Analysis of space flight instruments for solar terrestrial physics

A summary of the status of the Cross-section Facility at MSFC is presented. A facility was designed, fabricated, assembled, tested, and operated for measurement of differential scattering cross sections important to understand the induced environment for a vehicle (e.g., Space Station) in low earth orbit. A user's manual for the facility is also presented. The performance of the facility was evaluated and found to be satisfactory in all the essential areas. Differential scattering cross sections were measured and results for the scattering measurements are included. Input to the development of the Ultraviolet Imager Optical System is also discussed. Design, fabrication, and evaluation of UV filters using a four-layer aluminum base are reported.

Torr, Douglas G.↗

Vienna FORTRAN: A FORTRAN language extension for distributed memory multiprocessors

Exploiting the performance potential of distributed memory machines requires a careful distribution of data across the processors. Vienna FORTRAN is a language extension of FORTRAN which provides the user with a wide range of facilities for such mapping of data structures. However, programs in Vienna FORTRAN are written using global data references. Thus, the user has the advantage of a shared memory programming paradigm while explicitly controlling the placement of data. The basic features of Vienna FORTRAN are presented along with a set of examples illustrating the use of these features.

Chapman, Barbara↗

Lunar Development and Test Facility Virtual Walkthrough

This is a 3D virtual tour (VR) of the Lunar Development and Test Facility at Johnson Space Center. This tour will allow users to see the different aspects and projects throughout this facility. With clickable walk through circles that allow you to travel through the building along with interactive posters and monitors that give additional information on projects for the specific areas being viewed. The bottom left of the screen contains viewing options for changing positions as desired and bottom right offers a View in VR and a full screen option.

Kristopher Lee↗

Integrated scheduling and resource management

This paper examines the problem of integrated scheduling during the Space Station era. Scheduling for Space Station entails coordinating the support of many distributed users who are sharing common resources and pursuing individual and sometimes conflicting objectives. This paper compares the scheduling integration problems of current missions with those anticipated for the Space Station era. It examines the facilities and the proposed operations environment for Space Station. It concludes that the pattern of interdependecies among the users and facilities, which are the source of the integration problem is well structured, allowing a dividing of the larger problem into smaller problems. It proposes an architecture to support integrated scheduling by scheduling efficiently at local facilities as a function of dependencies with other facilities of the program. A prototype is described that is being developed to demonstrate this integration concept.

Ward, M. T.↗

Liquid helium servicing from the Space Station

The current concept of liquid helium resupply from the Space Station is discussed with regard to user and Space Station requirements, as well as requirements of the liquid helium servicing facility itself. A number of trade-offs which will affect both the hardware and the operation of the facility are presented. A total of 12 potential users have been identified. The users are divided into two groups: large volume users which are serviced every one to two years and small volume users which are serviced every few months. Both groups have a very strong impact on the definition of the liquid helium servicing facility. The facility components will be based on results of the Superfluid Helium On Orbit Transfer flight demonstration being conducted by NASA. Currently, the Space Station design includes a customer servicing bay which provides electrical power, thermal and contamination control, and connections for control and data handling systems. Restrictions on venting and vibrational disturbances on the Space Station may preclude servicing during quiescent periods when accelerations are minimal.

Breon, S. R.↗

Programming in Vienna Fortran

Exploiting the full performance potential of distributed memory machines requires a careful distribution of data across the processors. Vienna Fortran is a language extension of Fortran which provides the user with a wide range of facilities for such mapping of data structures. In contrast to current programming practice, programs in Vienna Fortran are written using global data references. Thus, the user has the advantages of a shared memory programming paradigm while explicitly controlling the data distribution. In this paper, we present the language features of Vienna Fortran for FORTRAN 77, together with examples illustrating the use of these features.

Chapman, Barbara↗

The design of models for cryogenic wind tunnels

Factors to be considered in the design and fabrication of models for cryogenic wind tunnels include high model loads imposed by the high operating pressures, the mechanical and thermodynamic properties of materials in low temperature environments, and the combination of aerodynamic loads with the thermal environment. Candidate materials are being investigated to establish criteria for cryogenic wind tunnel models and their installation. Data acquired from these tests will be provided to users of the National Transonic Facility.

Gillespie, V. P.↗

Space station needs, attributes and architectural options study. Volume 3: Mission requirements

User missions that are enabled or enhanced by a manned space station are identified. The mission capability requirements imposed on the space station by these users are delineated. The accommodation facilities, equipment, and functional requirements necessary to achieve these capabilities are identified, and the economic, performance, and social benefits which accrue from the space station are defined.

Source record↗

A shared-world conceptual model for integrating space station life sciences telescience operations

Mental models of the Space Station and its ancillary facilities will be employed by users of the Space Station as they draw upon past experiences, perform tasks, and collectively plan for future activities. The operational environment of the Space Station will incorporate telescience, a new set of operational modes. To investigate properties of the operational environment, distributed users, and the mental models they employ to manipulate resources while conducting telescience, an integrating shared-world conceptual model of Space Station telescience is proposed. The model comprises distributed users and resources (active elements); agents who mediate interactions among these elements on the basis of intelligent processing of shared information; and telescience protocols which structure the interactions of agents as they engage in cooperative, responsive interactions on behalf of users and resources distributed in space and time. Examples from the life sciences are used to instantiate and refine the model's principles. Implications for transaction management and autonomy are discussed. Experiments employing the model are described which the authors intend to conduct using the Space Station Life Sciences Telescience Testbed currently under development at Ames Research Center.

Johnson, Vicki↗

The GONG Data Reduction and Analysis System

Each of the six GONG observing stations will produce three, 16-bit, 256X256 images of the Sun every 60 sec of sunlight. These data will be transferred from the observing sites to the GONG Data Management and Analysis Center (DMAC), in Tucson, on high-density tapes at a combined rate of over 1 gibabyte per day. The contemporaneous processing of these data will produce several standard data products and will require a sustained throughput in excess of 7 megaflops. Peak rates may exceed 50 megaflops. Archives will accumulate at the rate of approximately 1 terabyte per year, reaching nearly 3 terabytes in 3 yr of observing. Researchers will access the data products with a machine-independent GONG Reduction and Analysis Software Package (GRASP). Based on the Image Reduction and Analysis Facility, this package will include database facilities and helioseismic analysis tools. Users may access the data as visitors in Tucson, or may access DMAC remotely through networks, or may process subsets of the data at their local institutions using GRASP or other systems of their choice. Elements of the system will reach the prototype stage by the end of 1988. Full operation is expected in 1992 when data acquisition begins.

Pintar, James A.↗

Space Station utilization

This paper focuses on the emphasis NASA has placed on Space Station utilization and the approach used to develop informed user communities in science, technology, and space commercialization. A major program objective continues to be the identification of potential Space Station users, assimilation of user requirements, and the use of those requirements both to drive the Station's design and to guide the Station's evolution. NASA's goal is the creation of a user friendly, multipurpose, multidiscipline research facility that will evolve on-orbit and maintain the position of a premiere space laboratory during its projected 30-year useful life.

Beck, Sherwim↗

Space station dynamics, attitude control and momentum management

The Space Station Attitude Control System software test-bed provides a rigorous environment for the design, development and functional verification of GN and C algorithms and software. The approach taken for the simulation of the vehicle dynamics and environmental models using a computationally efficient algorithm is discussed. The simulation includes capabilities for docking/berthing dynamics, prescribed motion dynamics associated with the Mobile Remote Manipulator System (MRMS) and microgravity disturbances. The vehicle dynamics module interfaces with the test-bed through the central Communicator facility which is in turn driven by the Station Control Simulator (SCS) Executive. The Communicator addresses issues such as the interface between the discrete flight software and the continuous vehicle dynamics, and multi-programming aspects such as the complex flow of control in real-time programs. Combined with the flight software and redundancy management modules, the facility provides a flexible, user-oriented simulation platform.

Sunkel, John W.↗

Acquisition plan for Digital Document Storage (DDS) prototype system

NASA Headquarters maintains a continuing interest in and commitment to exploring the use of new technology to support productivity improvements in meeting service requirements tasked to the NASA Scientific and Technical Information (STI) Facility, and to support cost effective approaches to the development and delivery of enhanced levels of service provided by the STI Facility. The DDS project has been pursued with this interest and commitment in mind. It is believed that DDS will provide improved archival blowback quality and service for ad hoc requests for paper copies of documents archived and serviced centrally at the STI Facility. It will also develop an operating capability to scan, digitize, store, and reproduce paper copies of 5000 NASA technical reports archived annually at the STI Facility and serviced to the user community. Additionally, it will provide NASA Headquarters and field installations with on-demand, remote, electronic retrieval of digitized, bilevel, bit mapped report images along with branched, nonsequential retrieval of report subparts.

Source record↗

Remote Operations and Ground Control Centers

The Payload Operations Integration Center at the Marshall Space Flight Center supports the International Space Station (ISS) through remote interfaces around the world. The POI$ was originally designed as a gateway to space for remote facilities; ranging from an individual user to a fullscale multi-user environment. This achievement was accomplished while meeting program requirements and accommodating the injection of modem technology on an ongoing basis to ensure cost operations. This paper will discuss the open POIC architecture developed to support similar and dissimilar remote operations centers. It will include technologies, protocols, and compromises which on a day to day basis support ongoing operations. Additional areas covered include centralized management of shared resources and methods utilized to provide highly available and restricted resources to remote users. Finally, the effort of coordinating the actions of participants will be discussed.

Bryant, Barry S.↗

Remote Operations and Ground Control Centers

The Payload Operations Integration Center (POIC) at the Marshall Space Flight Center supports the International Space Station (ISS) through remote interfaces around the world. The POIC was originally designed as a gateway to space for remote facilities; ranging from an individual user to a full-scale multiuser environment. This achievement was accomplished while meeting program requirements and accommodating the injection of modern technology on an ongoing basis to ensure cost effective operations. This paper will discuss the open POIC architecture developed to support similar and dissimilar remote operations centers. It will include technologies, protocols, and compromises which on a day to day basis support ongoing operations. Additional areas covered include centralized management of shared resources and methods utilized to provide highly available and restricted resources to remote users. Finally, the effort of coordinating the actions of participants will be discussed.

Bryant, Barry S.↗